CN101184462B - Controlling device of walking assisting device - Google Patents

Abstract

A walking assistance device (1), comprising a receiving part (2) supporting part of the weight of a user (A) from above, and a pair of left and right legs connected to the receiving part (2) via first joints (10R, 10L) The stand (3R, 3L), and the foot mounting part (15R, 15L) at the lower end of each leg stand (3R, 3L) is mounted on the foot of each leg of the user (A). Each leg support (3R, 3L) is connected to the receiving part (2) in the following manner, that is, in the support force acting on the leg support (3R, 3L) from the ground when each leg of the user (A) becomes a standing leg, From the third joint (14R, 14L) of the leg support (3R, 3L), the supporting force action line transmitted to the calf support (13R, 13L) is from the third joint (14R, 14L) when viewed from the sagittal plane. Through a predetermined point (P), wherein the predetermined point (P) is located above the receiving part (2) and within the width in the front-back direction of the contact surface between the receiving part (2) and the user (A). As a result, the user can be stably acted upon by the desired lifting force, which serves to relieve the user of the weight that would otherwise be borne by his legs.

Description

Controls for walking aids

technical field

The invention relates to a walking assisting device for assisting a user (person) to walk. the

Background technique

Conventionally, as such a walking assistance device, for example, a device shown in FIG. 4 of Japanese Patent Application Laid-Open No. 7-112035 (hereinafter referred to as Patent Document 1) is known. The device shown in Fig. 4 of this patent document 1 is: a pair of left and right leg supports are extended from the frame on the back of the user's body, and the foot members at the lower ends of each leg support are installed on the user's feet. Moreover, the saddle-shaped supporting part extending from the frame to the user's crotch can support part of the user's body weight. Each leg support has a first joint (equivalent to a hip joint) close to the frame, a second joint (equivalent to a knee joint) in the middle, and a third joint (equivalent to a foot joint) in the lower end. the

In the walking assistance device configured as shown in FIG. 4 of Patent Document 1, the first joint of each leg frame is provided on the back side of the user. Therefore, even if the driver only drives the second joint part of each leg frame to support part of the weight of the user, a force couple of the upward force acting on the back frame of the user and the downward force acting on the supporting part of the user will be generated. . And, due to this couple support part, it will be inclined forward and downward. Therefore, the position of the contact portion of the user with respect to the support part tends to be displaced, and it is considered that it is actually impossible to stably apply a desired lifting force to the user while supporting part of the user's body weight. Additionally, the described couple can be eliminated by driving the first joint. However, in this case, relatively complicated coordinated control of the first joint part and the second joint part of each leg frame is required. Meanwhile, in the above-mentioned patent document 1, when the lifting force is applied to the user by the support portion, the lifting force is shared by the left and right leg supports. However, the device in Patent Document 1 does not have a technique for appropriately distributing this lifting force to the left and right leg supports. Therefore, there is a possibility that a force inappropriate for the movement of the user's legs may be applied to the user's legs. the

Contents of the invention

The present invention has been accomplished with reference to the relevant background, and its purpose is to provide a walking assist device that can stably apply a desired lifting force to the user, and the lifting force is used to Reduce the weight that the user's legs should bear. Furthermore, it is another object of the present invention to provide a walking assistance device capable of appropriately sharing the lifting force with leg supports corresponding to the respective legs of the user. the

In order to achieve the above object, the first invention of the walking assisting device of the present invention is a walking assisting device comprising: a receiving part disposed between the bases of the user's legs to bear part of the user's weight from above A pair of left and right thigh frames, which are respectively connected to the receiving part through respective first joints arranged below the receiving part; a pair of left and right calf frames, which are respectively connected to each leg frame through their corresponding second joints Above: a pair of left and right foot mounting parts, which are respectively connected to each lower leg frame through their corresponding third joints, and are respectively installed on the feet of the left and right legs of the user, and on the user's Each leg of each leg is grounded when becoming a standing leg; the left side uses a driver, which drives the second joint of the left leg support, and the left leg support is composed of the first joint, thigh support, second joint, calf support on the left side , the third joint and the foot mounting part; the driver for the right side drives the second joint of the right leg support, and the right leg support is composed of the first joint, thigh support, second joint, The lower leg frame, the third joint, and the foot mounting part are composed, and the walking assistance device drives the second joint of each leg frame by the driver, so that the upward lifting force acts on the use from the receiving part. Or, it is characterized in that each leg support is connected to the said receiving part in the following manner, that is, when the user's sagittal plane is used to observe the leg support, when each leg of the user becomes a standing leg, Corresponding to the line of action of the supporting force of the third joint of the leg support of the leg acting on the calf support, from the third joint through the swing center point, the swing center point is located at the position above the receiving part and in the Within the width of the front-back direction of the contact surface between the receiving portion and the user, the walking assistance device further includes a mechanism that uses the support force as a control target force and uses the control target force as a predetermined target value for each leg frame. The drive is controlled in a manner such that the lifting force acts on the user. the

According to the first invention, the support force (vector) transmitted to the lower leg frame from the third joint of each leg frame is generated from the third joint toward a predetermined point located above the receiving portion and at the within the width in the front-rear direction of the contact portion between the receiving portion and the user. Therefore, the line of action (line passing through the center of gravity of the load distributed on the contact surface between the user and the receiving part) of the load (gravity equivalent to a part of the user's weight) applied to the receiving part by the user can be sufficiently reduced. The offset between the line of action of the supporting force acting on the calf frame from the third joint of each leg frame. That is, it is possible to sufficiently reduce the force couple on the receiving part generated by the load applied to the receiving part by the user and the supporting force acting on the lower leg frame from the third joint of each leg frame. As a result, the position and posture of the receiving portion can be kept stable with respect to the user. In addition, as described above, in the present invention, the support force toward the predetermined point from the third joint of each leg link is used as the control target force. Then, by driving the actuators so that the controlled force becomes a predetermined target value of each leg link, the lifting force is applied to the user. As a result, the required lifting force can be stably applied to the user. the

In addition, in the present invention, the supporting force (vector) acting on the calf frame from the third joint of each leg frame refers to the total supporting force for supporting the following weight sum on the ground, which is equivalent to the burden of each leg frame. Part of the force, the total weight includes part of the weight of the user (the weight supported by the lifting force applied to the user by the receiving part), and the part below the third joint of the left and right leg supports (foot part mounting part, etc.) (this weight is generally almost equal to the overall weight of the walking assist device). the

In the first invention, more specifically, the first joint of each of the leg supports is a joint that connects the thigh support of the leg support and the receiving part in such a manner that the leg support is connected by the specified The point is that the swing center point is free to swing at least in the front-back direction (second invention). the

Alternatively, the first joint of each leg support is a joint that connects the thigh support of the leg support and the receiving part in such a way that the leg support can swing freely in the front-rear direction and the left-right direction, and at least the front and rear of the leg support The swing center point in the direction is configured so that the predetermined point is located above the receiving portion. (the third invention). the

According to the second invention and the third invention, the supporting force acting on the calf frame from the third joint of each leg frame is the center point of swing from the third joint of the leg frame toward the front and back direction of the thigh frame of the leg frame (that is, the prescribed point) vector. Moreover, the swing center point of the leg brace in the front-back direction (hereinafter referred to as the front-back swing center point in this column) is located above the receiving part and in the front-rear direction of the contact surface between the receiving part and the user when viewed on the sagittal plane. within the width. Therefore, for example, when the load action line from the user to the receiving part is shifted to the front of the front and rear swing center point due to the user's upper body leaning forward, etc., and the receiving part becomes a forward-downward inclined posture, use The point of force acting on the receiving part is displaced rearwardly on the lower side of the center point of the forward and backward swing. Furthermore, the position and posture of the receiving part are automatically converged to a state where the load action line from the user on the receiving part passes through the center point of the back-and-forth swing. Moreover, when the line of action of the load applied by the user to the receiving part passes through the center point of the front and rear swing, the load and the force couple of the supporting force transmitted from the third joint of each leg support to the calf support will not be generated. The position of the head relative to the user is stabilized. In this manner, according to the second invention or the third invention, it is possible to prevent the positional displacement of the receiving portion with respect to the user. Furthermore, the lifting force of the receiving part to the user can be stabilized. In addition, in the third invention, the swing point in the left-right direction of the leg frame may be either above or below the receiving portion. the

The following is supplemented: In the second invention, the first joint part may be configured as follows, for example. That is, a pair of left and right arc-shaped or elliptical-arc-shaped (partial arc-shaped in the ellipse circumference) guide rails are connected to the receiving portion so that the arc center exists above the receiving portion. Furthermore, the first joint may be configured by supporting the guide rail so that the thigh frame of each leg frame can swing along the guide rail. In addition, in the third invention, for example, each of the guide rails is connected to the receiving portion via a pivot pin in the front-rear direction, and the guide rails are provided so as to be able to swing freely around the axis of the pivot pin. Thus, the first joint in the third invention is constituted. the

In addition, in the first to third inventions, preferably, the left side driver and the right side driver are connected to the thigh frame at positions closer to the receiving portion than the second joint. , and includes a pair of left and right power transmission mechanisms that transmit the driving force of each driver to the second joint. (the fourth invention). the

According to the fourth invention, since the heavy actuators are arranged near the receiving portion, the user equipped with the walking assist device can reduce the inertial force accompanying the movement of the free leg side actuators during walking motion. Therefore, the burden on the user can be reduced. In addition, the power transmission mechanism may, for example, be a pipe or a shaft through which a cable, a link, or a liquid passes. the

The control of the control object force in the first to fourth inventions will be described more specifically below. The walking assistance device preferably includes a pedaling force measurement mechanism, which is installed on each of the feet according to The first force sensor on the part outputs the displayed force detection value to measure the pedaling force of each leg of the user; the target lifting force setting mechanism sets the target lifting force, which is obtained from the bearing Part of the target value of the upward lifting force acting on the user; the second force sensor is installed between the lower end of the calf frame of each leg frame and the third joint, or the third joint of each leg frame Between the joint and the foot mounting part; the control object force measurement mechanism, which according to the force detection value output and displayed by the second force sensor, will actually act on the calf frame from the third joint of each leg frame. Measured as the control object force; the total target lifting force determination mechanism, which determines the sum of the target lifting force and the supporting force as the total target lifting force, and the supporting force is used to move from the walking assistance The difference weight obtained by subtracting the total weight of the lower parts of the second force sensors in the walking assisting device from the overall weight of the device is supported on the floor, or is used to support the entire weight of the walking assisting device on The supporting force of the floor; the distribution mechanism, which distributes the total target lifting force to each of the leg supports according to the ratio of the pedaling force of the user's left leg to the pedaling force of the right leg, thereby determining the total The target load as the target value of the load of the left leg support and the target load as the target value of the target load of the right leg support in the target lifting force; the driver control mechanism, which is based on the left leg support The control object force of the left leg frame and the target load of the left leg frame are controlled so that the difference between the control object force of the left leg frame and the target load is close to 0, and the actuator for the left side is controlled according to the The control object force of the right leg frame and the target load of the right leg frame are controlled so that the difference between the control object force of the right leg frame and the target load is close to 0. driver. (the fifth invention). the

According to the fifth invention, the total target lifting force is determined as the total target lifting force by the sum of the following forces: the target lifting force set by the target lifting force setting mechanism and the The total weight of the assisting device minus the weight of the total weight of the lower parts of the second force sensors in the walking assisting device (in this column, the weight is hereinafter referred to as weight X) is the sum of the supporting forces supported on the ground, Alternatively, it may be the sum of the target lifting force and a support force for supporting the entire weight of the walking assist device on the ground. The total target lifting force refers to the necessary supporting force that the following sum of gravity is supported on the ground by the two leg supports or the leg support on one side. The sum of the force to balance the force) and the weight X of the walking assist device or the gravity equivalent to its overall weight. In addition, the weight X of the walking assist device is generally almost equal to the overall weight. the

Furthermore, in the fifth invention, the total target lift-up force is distributed based on the ratio of the pedaling force of the user's right leg to the pedaling force of the left leg measured by the pedaling force measuring means. From this, the target load of the left leg frame and the target load of the right leg frame in the total lifting force are determined. In this case, the ratio of the pedaling force of the user's right leg to the pedaling force of the left leg measured by the pedaling force measuring means reflects how the user supports his or her weight on the ground with each leg. For example, when the pedaling force of the left leg is greater than that of the right leg, the user mainly uses the right leg to support his body weight. Therefore, by distributing the total target lifting force to each leg frame of the walking assist device according to the ratio of the pedaling force of the user's right leg to the pedaling force of the left leg to determine the target bearing amount of each leg frame, the target lifting force can be divided into The user's desired form is assigned to each leg support according to the motion state of each leg. That is, the ratio of the target load of the right leg link to the target load of the left leg link can be determined based on the ratio of the pedaling force of the right leg and the pedaling force of the left leg, which represent the movement of each leg desired by the user. At the same time, more specifically, for example, it is only necessary to make the ratio of the target lifting load of the right leg support relative to the target lifting force and the ratio of the right pedaling force relative to the sum of the user's right leg pedaling force and left leg pedaling force Scale the same way to determine the target lift load for the right leg brace. In addition, it is only necessary to determine the ratio of the target lifting load of the left leg support to the target lifting force and the ratio of the left pedaling force to the sum of the pedaling force of the user's right leg and the pedaling force of the left leg. Target lift commitment for the left leg brace. Supplementary description of the following content: the target load of the left leg frame has the meaning of the target value of the control object force of the left leg frame; the target load of the right leg frame has the meaning of the target force of the right leg frame Describe the meaning of the target value of the control object force. the

Furthermore, in the fifth invention, based on the left leg frame control target force measured by the control target force measuring means (the support force actually acting on the calf frame from the third joint of the left leg frame) and the The distribution means controls the left side actuator so that the difference between the left leg frame control target force and the target load is close to zero. Similarly, according to the control object force of the right leg support measured by the control object force measuring mechanism (the supporting force actually acting on the lower leg support from the third joint of the right leg support) and the right side force determined by the distribution mechanism The target load of the leg frame is controlled so that the difference between the right leg frame control target force and the target load is close to zero. the

By controlling each driver in this way, it is possible to reliably control the actual load of each leg frame so that it becomes the target load. In addition, at this time, the actual lifting force acting on the user from the receiving portion can be controlled so as to be the above-mentioned target lifting force. the

Thus, in the fifth invention, while considering the weight of the walking assist device, the total target lifting force can be shared by the left and right leg supports in accordance with the user's desired state of movement of each leg, and the set The set target lifting force properly acts on the user from the receiving portion. As a result, the burden on the user's legs is more effectively reduced. the

In addition, as another aspect different from the fifth invention, in the first to fourth inventions, the walking assistance device may further include: a pedaling force measuring mechanism, which is provided on each foot according to The first force sensor on the upper mounting part outputs the force detection value displayed to measure the pedaling force of each leg of the user; the second force sensor is installed between the lower end of the calf frame of each leg frame and the third joint Between, or between the third joint of each leg bracket and the foot mounting part; the control object force measuring mechanism, which will actually act from the third joint of each leg bracket according to the force detection value output and displayed by the second force sensor The support force on the calf frame is measured as a controlled object force; a target assist ratio setting mechanism that sets a target assist ratio that is the sum of the pedaling forces of each leg of the user The target value of the ratio of the force that should be assisted by the walking assist device to the total pedaling force in the total pedaling force; the target lifting load determination mechanism that multiplies the target assistance ratio by the pedaling of each leg of the user In the upward lifting force that should act on the user from the receiving part, the target lifting load as the target value of the load of the left leg frame and the target value of the load of the right leg frame are determined by using the force. The target lift commitment of the target value;

A distributing mechanism for distributing the supporting force to each of the leg frames according to the ratio of the pedaling force of the user's left leg to the pedaling force of the right leg, whereby the bearing force of the left leg frame in the supporting force is and the bearing amount of the right leg frame are respectively determined as the target device supporting force bearing amount of each leg frame. The difference between the total weight of the lower portion of the second force sensor is a support force for supporting the floor, or a support force for supporting the entire weight of the walking assist device on the floor; the control target force target value determination mechanism sets The sum of the target lifting commitment of the left leg support and the target device supporting force is determined as the target value of the control object force of the left leg support, and the target lifting commitment of the right leg support The sum of the supporting force of the target device and the bearing capacity of the target device is determined as the target value of the control object force of the right leg support; the driver control mechanism, which is based on the control object force of the left leg support and the control of the left leg support The target value of the target force is such that the difference between the control target force of the left leg frame and the target value is close to 0 to control the left driver, and according to the control target force of the right leg frame and The target value of the control target force of the right leg link is controlled so that the difference between the control target force of the right leg link and the target value approaches zero (sixth invention). the

In the sixth invention, the self-supporting portion is determined by multiplying the target assist ratio set by the target assist ratio setting means by the pedaling force of each leg of the user measured by the pedaling force measuring means. The target lift load of the left leg support and the target lift load of the right leg support are to act on the upward lift force of the user. That is, by multiplying the target assist ratio by the measured pedaling force of the user's left leg to determine the target lifting load of the left leg frame, by multiplying the target assist ratio by the measured user's right leg pedaling force to determine Determines the target lift effort for the right leg brace. At the same time, the sum of the target lifting load of the left leg frame and the target lift load of the right leg frame is equivalent to the target value of the total lifting force acting on the user from the receiving portion. This sum nearly equals the user's full pedaling force multiplied by the target assist ratio. the

In this case, the pedaling force of the user's right leg and the pedaling force of the left leg measured by the pedaling force measuring mechanism reflect how the user puts his entire body weight through each leg, as explained in the fifth invention. means to rest on the ground. Therefore, as described above, by determining the target lifting load of each leg support, the target value ( The sum of the target lifting capacity of each leg frame) is allocated to each leg frame. the

And in the sixth invention, according to the ratio of the pedaling force of the user's left leg to the pedaling force of the right leg measured by the pedaling force measuring means, the following supporting force is distributed to each of the leg supports, the supporting force being Refers to the support force used to support the ground on the ground by subtracting the total weight of the walking aid device from the total weight of the parts below the second force sensors in the walking aid device (i.e. the weight X), or used to support the walking aid device The supporting force of the whole weight of the walking assist device on the ground. Accordingly, the bearing amount of the left leg link and the bearing amount of the right leg link among the target values of the supporting force are respectively determined as target device supporting force bearing amounts of the respective leg links. That is, the supporting force for supporting the weight X of the walking assistance device or the entire weight on the ground (the The support force refers to the force that balances the weight X of the walking assist device or the gravity of the whole weight. Hereinafter, it is referred to as the device support force in this column) to be distributed to each leg support to determine the target device of each leg support Amount of bearing capacity. In addition, more specifically, for example, it is only necessary to make the ratio of the target device supporting force bearing amount of the right leg support to the target value of the device supporting force and the right pedaling force relative to the user's right leg pedaling force and left leg In the same manner, the ratio of the sum of pedaling forces is used to determine the target device supporting force bearing amount of the right leg support. Similarly, it only needs to make the ratio of the target device supporting force bearing amount of the left leg support relative to the target value of the device supporting force and the ratio of the left pedaling force relative to the sum of the user's right leg pedaling force and left leg pedaling force be In the same way, determine the bearing capacity of the target device for the left leg support. the

Furthermore, in the sixth invention, the target lift commitment amount of the left leg frame determined by the target lift load determination means and the target device support force commitment of the left leg frame determined by the distribution means are combined. The sum of the quantities is determined as the target value of the control object force of the left leg support. Similarly, the sum of the target lifting commitment of the right leg frame determined by the target lifting load determination mechanism and the target device supporting force load of the right leg frame determined by the distribution mechanism is determined as the right The target value of the control object force of the side leg bracket. The following content is supplemented: the target value of the control object force of the left leg frame and the target value of the control object force of the right leg frame in the sixth invention are respectively equivalent to the target value of the left leg frame in the sixth invention. Capacity, target capacity for right leg support. the

Accordingly, the target value of the controlled force of each leg link is determined so as to correspond to the ratio of the pedaling force of the right leg and the pedaling force of the left side, which reflect the movement of each leg desired by the user. At this time, the target value of the controlled object force of each leg support is the sum of the target lift commitment of the leg support and the target device support force commitment. Therefore, the sum of the target value of the control object force on the leg supports corresponds to the lifting force that should act on the user from the supporting portion and the weight X for supporting the walking assist device or the entire weight on the ground. The sum of the supporting forces. the

Furthermore, in the sixth invention, the control target force of the left leg link measured by the control target force measuring means and the control target force of the left leg link determined by the control target force target value determination means The left side actuator is controlled so that the difference between the control object force of the left leg support and the target value is close to zero. Similarly, the control target force of the right leg frame measured by the control target force measuring means and the target value of the control target force of the right leg frame determined by the control target force target value determination means are set such that the right The right side actuator is controlled so that the difference between the controlled force of the side leg frame and the target value becomes close to zero. the

Thereby, the actual control target force of each leg support (the control target force is equivalent to the actual bearing amount of each leg support with respect to the following total support force, and the total support force is used to support the user's actual load) The load on the receiving portion (the force that balances the lifting force that actually acts on the user upward from the receiving portion) and the weight X of the walking assist device or the force of the entire weight) are reliably controlled to target values. At the same time, it is possible to control the actual lifting force acting on the user from the receiving portion to a lifting force corresponding to the full pedaling force of the user multiplied by the target assist ratio. the

Thus, in the sixth invention, while considering the weight of the walking assist device, the left and right leg supports can share and support the user's entire body weight multiplied by the target assist in a manner that conforms to the operating state of each leg desired by the user. At the same time, the lifting force is properly applied from the receiving portion to the user due to the lower weight. As a result, the burden on the user's legs can be more effectively reduced. the

Therefore, according to the sixth invention, while reducing the number of mounting members attached to the user's legs, the force of the user's legs supported on the ground is reduced, and at the same time, it is possible to use the leg supports corresponding to the user's legs. This assisting force (lifting force) for alleviating the aforementioned force is shared. the

Supplementary description of the following content: In the first to sixth inventions described above, the receiving portion can be, for example, a seat that the user can sit on (so that the seat portion is located between the user's two legs and the user sits on the seat) A member (for example, a saddle-shaped member) on the seat portion. In this case, the first joint of each leg frame is preferably provided below the receiving portion. In addition, the first joint of each leg frame is preferably, for example, a joint capable of not only swinging each leg frame in the front-back direction, but also having the freedom to rotate about two axes to allow each leg frame to swing in and out. Spend. Furthermore, the first joint may be a joint that can rotate each leg frame around an axis in the vertical direction (inward rotation and outward rotation of each leg frame), and has a degree of freedom of rotation around three axes. In addition, the second joint of each leg link may be, for example, a joint having a degree of freedom of rotation about one axis in the left-right direction, or may be a direct motion joint. In addition, although the third joint of each leg frame is preferably a joint having degrees of freedom of rotation around three axes, it may be a joint having degrees of freedom of rotation about two axes including the left and right directions. In addition, it is preferable that the foot mounting portion of each of the leg supports is configured, for example, in such a manner that it has a ring member through which the user’s foot can be inserted from the toe end, and passes through the ring member. The foot mounting part is connected to the third joint of the leg frame. the

In addition, the first force sensor of each foot mounting part may be mounted on the foot mounting part in such a manner that when each leg of the user is a standing leg, the first force sensor is interposed between the standing legs. Between the bottom of the foot and the ground. Or, for example, when the foot mounting portion of each leg frame has the ring-shaped member, the foot mounting portion of each leg frame is arranged inside the ring-shaped member in a state of non-contact with the ring-shaped member. A foot support member supports the user's foot. And, the foot support member is suspended from the ring member via the first force sensor. the

Description of drawings

Fig. 1 is a side view (view seen from a sagittal plane) showing a walking assistance device according to a first embodiment of the present invention. the

Fig. 2 is a front view taken along line II in Fig. 1 . the

Fig. 3 is a sectional view taken along line III-III in Fig. 1 . the

Fig. 4 schematically shows the configuration (hardware configuration) of the control device of the walking assistance device according to the first embodiment shown in Fig. 1 . the

5 is a block diagram showing a functional configuration of an arithmetic processing device provided in the control device in the first embodiment. the

FIG. 6 is a block diagram showing a processing flow of the pedaling force processing mechanism of FIG. 5 . the

FIG. 7 is a diagram showing a table used in the process of S104 in FIG. 6 . the

8 is a block diagram showing the processing flow of the knee angle measurement processing means and the supporting force measurement processing means of FIG. 5 . the

FIG. 9 is a diagram for explaining the processing of S201 and S203 in FIG. 8 . the

FIG. 10 is a block diagram showing the processing flow of the left and right target burden determination means in FIG. 5 . the

FIG. 11 is a block diagram showing the processing flow of the feedback operation amount determining means in FIG. 5 . the

FIG. 12 is a block diagram showing a processing flow of the feedforward operation amount determining means in FIG. 5 . the

FIG. 13 is a diagram for explaining the processing of S502 in FIG. 12 . the

14 is a block diagram showing a functional configuration of an arithmetic processing unit provided in a control device in a walking assistance device according to a second embodiment of the present invention. the

FIG. 15 is a block diagram showing the processing flow of the left and right target burden determination means in FIG. 14 . the

Fig. 16 is a diagram illustrating a configuration example of a receiving portion in a third embodiment of the present invention. the

FIG. 17 is a graph showing an example of a table used in the process of S104 in FIG. 6 in the fourth embodiment of the present invention. the

Fig. 18 is a diagram showing a configuration of a leg mounting portion in a fifth embodiment of the present invention. the

Detailed ways

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In addition, this first embodiment is the embodiment of the first to fifth inventions described in the present application. the

First, the configuration of the walking assistance device in this embodiment will be described with reference to FIGS. 1 to 3 . FIG. 1 is a side view of the walking assistance device 1 , FIG. 2 is a front view along line II in FIG. 1 , and FIG. 3 is a cross-sectional view along line III-III in FIG. 1 . In addition, the walking assistance device 1 in FIGS. 1 to 3 shows a state in which it is mounted on the user A (shown by phantom lines) and operated. In this case, the illustrated user A is in a standing state almost in an upright posture. However, in FIG. 2 , in order to facilitate the understanding of the structure of the walking assistance device 1 , the user A adopts a posture with his legs separated left and right. the

Referring to FIGS. 1 and 2 , the walking assistance device 1 is a weight reduction assisting device that supports part of the user's body weight (reduces the weight supported by the user's own legs (standing legs) so that it is lighter than the user's body weight). The walking assistance device 1 includes a seat portion 2 on which the user A sits, and a pair of left and right leg supports 3L, 3R connected to the seat portion 2 . The leg supports 3L and 3R have the same structure. In addition, in FIG. 1 , the leg rests 3L, 3R are arranged in the same posture in the left-right direction of the user A (direction perpendicular to the paper surface of FIG. 1 ). This state is superimposed on the figure (the left leg support 3L is at the front position in the figure). the

Here, in the description of the embodiment of this specification, the symbol "R" is used to indicate the meaning related to the right leg of the user A or the right leg support 3R of the walking assist device 1, and the symbol "L" is used to indicate the meaning related to the user A's right leg. The left leg or the left leg support 3L of the walking assistance device 1 is related. However, when there is no need to distinguish between left and right, symbols R and L are usually omitted. the

The seat part 2 is a saddle-shaped member, and the user A can straddle the seat part 2 (the seat part 2 is arranged so as to be located between the roots of the legs of the user A) and sit on the seat part 2 (the seat surface). When seated, part of the body weight of the user A is added to the seat portion 2 from above. In addition, the seating part 2 corresponds to a receiving part in this invention. the

In addition, as shown in FIG. 1 , the front end portion 2f and the rear end portion 2r of the seating portion 2 protrude upward, whereby the seating position (position in the front-rear direction) of the user A relative to the seating portion 2 can be limited to the Between the front end part 2f and the rear end part 2r of the part 2. At the same time, the front end portion 2f of the seating portion 2 is formed in a bifilar shape as shown in FIG. 2 . the

Each leg support 3 has a thigh frame 11, a calf frame 13 and a foot mounting part 15 respectively; wherein, the thigh frame 11 is connected to the lower part of the seating part 2 via the first joint 10, and the calf frame 13 is connected to the thigh via the second joint 12 Frame 11 , the foot mounting part 15 is connected to the calf frame 13 via the third joint 14 . the

The first joint 10 of each leg frame 3 corresponds to the hip joint of the user A, and the swing motion of the leg frame 3 around the left-right axis (the swing motion of the leg frame 3 in the front-back direction) and the swing motion around the front-back axis (Swing in, swing out) becomes possible. The first joint 10 is arranged on the lower side of the seating part 2, and includes a pair of pin shafts 20f, 20r, brackets 21f, 21r rotatably supported by the pin shafts 20f, 20r, and fixed to the brackets 21f, The arc-shaped guide rail 22 at the lower end of 21r and the plate 23 supported on the guide rail 22 to move freely along the guide rail 22, wherein: the pair of pin shafts 20f, 20r are arranged on the lower part of the seating part 2 near the at the front side and the rear end, and are disposed coaxially with the axis C in the front-rear direction shown by the dotted line in FIG. 1 . In addition, the thigh rest 11 extends obliquely forward and downward from the plate 23 . The thigh frame 11 is a substantially link-shaped member, and is integrally formed with the plate 23 . the

Each pin shaft 20f, 20r is fixed on the seating part 2 via a bearing, wherein the respective two ends (front and rear ends) of the bearings are fixed on the lower surface of the seating part 2 . In addition, the upper end portion of the bracket 21f is fitted to the outer periphery of the middle portion of the pin shaft 20f and is pivotally supported by the pin shaft 20f, and the bracket 21f is rotatable about the axis C of the pin shaft 20f. Similarly, the upper end of the bracket 21r is fitted into the outer periphery of the middle part of the pin shaft 20r and is pivotally supported by the pin shaft 20r, and the bracket 21r is free to rotate around the axis C of the pin shaft 20r. Therefore, the guide rail 22 of each first joint 10 can swing around the axis C of the pin shafts 20f, 20r together with the brackets 21f, 21r as the rotation axis. In addition, in this embodiment, the rotation axes of the first joints 10R and 10L of the leg supports 3R and 3L are the same as the rotation axis C, and the first joint 10R of the leg support 3R and the first joint 10L of the leg support 3L Place shared bearing pin 20f, 20r. That is, both the bracket 21fR of the first right joint 10R and the bracket 21fL of the first left joint 10L are pivotally supported on the same pin shaft 20f, and the bracket 21rR of the first right joint 10R and the left Any one of the brackets 21rL of the first side joint 10L is pivotally supported by the same pin shaft 20r. the

The plate 23 of the first joint 10 of each leg frame 3 is disposed close to the guide rail in a posture parallel to the surface including the arc of the guide rail 22 . As shown in FIG. 1 , a support 26 having a plurality of (for example, four) freely rotatable rollers is fixed on the plate 23 . And, the rollers 25 of the support 26 are rotatably engaged with the upper surface (inner peripheral surface) and the lower surface (outer peripheral surface) of the guide rail 22 in such a manner that the upper and lower surfaces are the same number. Thereby, the plate 23 can move freely along the guide rail 22 . In this case, the positional relationship between the guide rail 22 and the seating portion 2 and the arc radius of the guide rail 22 are set in such a manner that when the walking assistance device 1 is viewed on the sagittal plane as shown in FIG. The center point P of the arc of is present on the upper side of the seat part 2 within the width in the front-rear direction of the contact surface of the seat part 2 and the user A. This central point P corresponds to a predetermined point in the present invention. the

According to the configuration of the first joint 10 described above, the thigh frame 11 integrated with the plate 23 can swing freely around the rotation axis C of the user A in the front-back direction. Each leg frame 3 can perform an inward swing and an outward swing through this swinging motion. In addition, the thigh frame 11 integrated with the plate 23 revolves around the axis in the left-right direction passing through the center point (predetermined point) P (more precisely, around the plane perpendicular to the arc including the guide rail 22 and passing through the center point P). axis) swings freely. By this swinging action, the forward and backward swinging action of each leg support 3 becomes possible. In addition, in the present embodiment, the second joint 10 is a joint capable of rotating around two axes, the front-rear direction and the left-right direction. However, it is also possible to configure the first joint in such a manner that it can rotate about an axis in the vertical direction (inward swing and outward swing of each leg frame 3 ) (that is, it can rotate about three axes). Alternatively, the first joint may be a joint capable of turning only about one axis in the left-right direction (each leg frame 3 is a joint capable of only swinging forward and backward). the

Furthermore, when the walking assistance device 1 is viewed from the sagittal plane as shown in FIG. 1 , the plate 23 of the first joint 10 of each leg support 3 extends from the support 26 to the rear of the seat portion 2 . Further, a motor 27 and a rotary encoder 28 as a rotation angle measuring means for measuring a rotor rotation angle of the motor 27 (rotation angle from a predetermined standard position) are coaxially provided on the rear end portion of the plate 23 . In this embodiment, the second joint 12 among the first to third joints 10 , 12 , 14 of each leg support 3 can be driven, and the motor 27 is an actuator for driving the second joint 12 . At the same time, the rotary encoder 28 has a function as a displacement sensor for measuring the displacement amount (rotation angle) of the second joint 12 . The rotation angle measured by this rotary encoder is used to measure the rotation angle (bending angle) of the second joint 12 . In addition, the motor 27L of the left leg frame 3L and the motor 27R of the right leg frame 3R correspond to the operation mechanism for the left side and the operation mechanism for the right side, respectively, in the present invention. Each operating mechanism can also use oil pressure or air pressure operating mechanism. Moreover, each operating mechanism can also be fixed to the rear of the seating part 2 via a suitable bracket, for example. Alternatively, each operating frame can also be installed at the second joint 12 of each leg support 3 and directly drive the second joint 12 . Meanwhile, the displacement sensor for measuring the displacement of the second joint 12 can be directly installed at the second joint 12 of each leg support 3 . Furthermore, the displacement sensor may be constituted by a potentiometer or the like instead of the rotary encoder. the

The second joint 12 of each leg frame 3 corresponds to the knee joint of the user A, and is a joint capable of extending and bending the leg frame 3 . The second joint 12 connects the lower end of the thigh frame 11 and the upper end of the calf frame 13 via a pin shaft 29 having a left-right axis (more precisely, an axis perpendicular to the surface including the arc of the guide rail 22). , and make the lower leg frame 13 rotate freely relative to the thigh frame 11 around the axis of the pin shaft 29 . In addition, a stopper (not shown) is provided on the second joint 12 to limit the possible range of rotation of the calf frame 13 relative to the thigh frame 11 . the

The calf frame 13 of each leg frame 3 is a substantially link-shaped rod extending obliquely downward from the second joint 12 of the leg frame 3 . More specifically, the lower leg frame 13 is composed of a lower leg frame 13b, a rod-shaped upper leg frame 13a, and a force sensor 30 (which is equivalent to the second force sensor in the present invention) interposed between the two to form a connection. , wherein, the lower calf frame 13b constitutes the part close to the third joint 14; the rod-shaped upper calf frame 13a constitutes the part located on the upper side of the lower leg frame 13b. On the other hand, the lower leg frame 13b is set to be very short compared with the upper leg frame 13a. Accordingly, the force sensor 30 is arranged near the third joint 14 . The force sensor 30 is a force sensor called a Kistler sensor (registered trademark of Kistlersensor), and measures a three-axis translational force (the translational force in the direction of the axis perpendicular to the surface of the force sensor 30 and the direction parallel to the surface and perpendicular to each other). translational force in the 2-axis direction) of the 3-axis force sensor. However, in this embodiment, as described later, only the measured values of the biaxial force among the measured triaxial translational forces are used. Therefore, the force sensor 30 can also be constituted by a 2-axis force sensor for measuring 2-axis translation force. the

In addition, a pulley 31 is fixed on the upper end of the lower leg frame 13 a on the upper part of the lower leg frame 13 , and the pulley is integral with the lower leg frame 13 and can freely rotate around the pin shaft 29 of the second joint 12 . The ends of a pair of cables 32 a and 32 b are fixed to the outer peripheral portion of the pulley 31 , and the pair of cables serve as a drive transmission mechanism to transmit the rotational driving force of the motor 27 to the pulley 31 . The cables 32 a , 32 b are drawn out from two positions on the outer periphery of the pulley 31 diametrically opposed to each other along the tangential direction of the pulley 31 . The cables 32a and 32b are passed through unshown rubber tubes (cable protection tubes) arranged along the thigh frame 11, and are connected to a rotation drive shaft (not shown) of the motor 27. In this case, the pulling force from the motor 27 is applied to the cables 32a, 32b in such a manner that one of the cables 32a, 32b is caught by the pulley 31 due to the normal rotation of the drive shaft by the motor 27. At the same time, the other side of the cables 32a, 32b is drawn out while the other side of the cables 32a, 32b is drawn in by the pulley 31 due to the reversal of the rotation drive shaft of the motor 27. Thus, the rotational driving force of the motor 27 is transmitted to the pulley 31 through the cables 32a, 32b, and the pulley 31 can be driven to rotate (the calf frame 13 fixed with the pulley 31 rotates around the pin shaft 29 of the second joint 12). The axis rotates relative to the thigh frame 11). the

In addition, the lower end portion of the calf frame 13b at the lower portion of the calf frame 13 is constituted by a bifurcated portion 13bb formed in a bifilar shape as shown in FIG. 3 . the

The third joint 14 of each leg frame 3 corresponds to the ankle joint of the user A. As shown in FIG. In this embodiment, as shown in FIG. 3 , the third joint 14 is composed of a universal joint 33 (refer to FIG. 3 ) that can rotate around three axes. In the two-legged part 13bb of 13b, the lower end part (two-legged part 13bb) of the calf frame 13 and the connecting part 34 at the upper part of the foot mounting part 15 are connected. Accordingly, the foot mounting portion 15 can rotate with respect to the calf frame 13 in three degrees of freedom. In addition, regarding the rotation of the foot mounting part 15 around the axis in the front-rear direction, the possible range of rotation can be limited by the bifurcated part 13bb. the

The foot mounting part 15 of each leg frame 3 has a shoe body 35 worn by each foot of the user A, and a stirrup-shaped ring member 36 accommodated inside the shoe body 35 and whose upper end is fixed to the connecting part 34 . As shown in FIG. 3 , the annular member 36 is housed inside the shoe body 35 in such a manner that its flat bottom plate abuts on the inner bottom surface of the shoe body 35 and connects the curved edges at both ends of the bottom plate. The upper portion abuts against the side wall along the cross section of the shoe body 35 . In addition, a flexible inner pad member 37 (not shown in FIG. 1 ) is inserted into the shoe body 35 to cover the bottom surface inside the shoe body 35 and the bottom plate portion of the annular member 36 . In addition, the connecting portion 34 is inserted into the shoe body 35 through the opening of the shoe lacing portion of the shoe 35 . the

When installing the foot mounting part 15 of each leg support 3 on each foot of the user A, the tip of the toe of the foot is passed through the inside of the ring member 36, and the inner cushion member 37 is placed on the foot. The foot of the user A is inserted into the inside of the shoe body 35 from the insertion opening of the shoe body 35, and the foot mounting portion 15 is mounted on the foot by fastening the shoe body strap. the

And, under the inner pad member 37 of the foot mounting portion 15, at the front side position of the shoe body 35 (the position closer to the bottom plate portion of the ring member 36) and the rear side position (than the bottom plate portion of the ring member 36). The bottom plate will be positioned behind) force sensors 38,39 are arranged. The front side force sensor 38 is provided so as to be located approximately directly below the MP joint (middle phalanx joint) of the foot of the user A equipped with the foot mounting part 15 . At the same time, the rear side force sensor 39 is arranged so as to be located approximately directly below the heel of the foot. In this embodiment, these force sensors 38 and 39 are uniaxial force sensors, and measure the direction perpendicular to the bottom surface (contact surface) of the foot mounting part 15 (the leg of the user A is approximately perpendicular to the ground in an upright state). direction) translation force. Hereinafter, the force sensors 38 and 39 are referred to as the MP sensor 38 and the heel sensor 39, respectively. Meanwhile, the MP sensor 38 and the heel sensor 39 together form the first force sensor in the present invention. Here, the inner pad member 37 does not necessarily have to be a rigid plate, but may be made of a soft (flexible) material. When the inner pad member 37 is made of a soft material, by disposing a plurality of first force sensors under it, it is possible to accurately measure the force of each part of the bottom surface of the user A's foot. On the other hand, when the inner pad member 37 is formed of a rigid plate, the pedaling force of the entire foot of the user A can be easily measured. Therefore, the number of first force sensors provided under the inner pad member 37 can be reduced. the

The above is the configuration of the walking assistance device 1 of the present embodiment. Supplementary description of the following: User A installs each foot mounting part 15 on each foot of user A and operates the walking assistance device (driving the second joint 12 with the motor 27) as described later. When sitting on the seat part 2, when the user A and the walking assistance device 1 are viewed from the forehead (viewing the user A from the front), for example, the thigh support 11L of the left leg support 3L is along the left leg of the user A. The inner surface is extended (refer to FIG. 2 ), and the second joint 12L at the lower end of the second bracket 11L is also located on the inner side of the left leg. In addition, although illustration is omitted, the upper portion of the calf frame 13L connected to the second joint 12L (the upper portion of the upper calf frame 13L) extends from the second joint 12L along the inner surface of the user A's left leg when viewed from the forehead. , And, the lower side portion of the lower leg frame 13L is gradually bent, and is formed at the front side of the shin of the left leg to directly above the instep of the left leg. The same applies to the right leg support 3R. the

In addition, when a user A of average body size stands upright, the second joints 12 of each leg support 3 protrude forward than the legs of the user A as shown in FIG. 1 . That is, the length of the thigh frame 11 and the length of the calf frame 13 are set so that the sum of these two lengths is slightly longer than the crotch leg length of the user A of the general build. When the length of the thigh frame 11 and the calf frame 13 is set in this way, the singular point state in which the thigh frame 11 and the calf frame 13 become a straight line cannot be produced by means of the stopper arranged at the second joint 12 and is consistent with that shown in FIG. 1 The thigh frame 11 and the calf frame 13 are shown in a state of reverse bending. As a result, it is possible to prevent the walking assistance device 1 from being unable to be controlled due to the singularity state and reverse bending state of each leg frame 3 . the

In addition, the second joint of each leg frame 3 may be a linear joint. the

Using the walking assistance device 1 constituted as above, in the state where the foot mounting part 15 is mounted on the foot of each leg of the user A, each second joint 12 is generated by each motor 27 to generate torque, and the seat part 15 is connected to the seat part. 2. An upward lifting force acts on the user A, which will be described in detail later. At this time, for example, in a state where the legs of the user A are standing (legs supporting the body weight of the user A) (the state of the so-called two-leg support phase), the two foot mounting parts 15, 15 touch the ground, And there is ground reaction force acting on its contacting surface respectively. The resultant force of the ground reaction force acting on the contact surface of each foot mounting part 15 is the ground reaction force that is balanced with the sum of the gravity acting on the user A and the gravity acting on the walking assist device 1, that is, the resultant force of the ground reaction force acting on the user A. The force (translational force; hereinafter referred to as total support force) of the total weight of both of the walking assist device and the walking assist device 1 is supported on the ground. In addition, when the legs of the user A and the leg support 3 of the walking assistance device 1 are walking simultaneously, to be precise, the full supporting force should also be supported by the movement of the free leg of the user A and the walking assistance device 1. However, in the walking assistance device 1 of this embodiment, the heavy motor 27 (driver) and the encoder 28 are not near the knees but are installed near the waist. Moreover, since the part constrained (device) by the user A in each of the leg supports 3 is only the foot mounting part 15, the number of device components installed on the user A is small, and each leg support 3 is a lighter member. . Therefore, the inertial force accompanying the movement of the free leg of the walking assistance device 1 becomes sufficiently small. the

In this case, in the walking assistance device 1 of the present embodiment, only the two leg attachment parts 15 and 15 are mounted on the user A and restrained. At the same time, the ring-shaped member 36 is provided on each leg attachment portion 15 . Therefore, the gravity acting on the walking assisting device 1 and the load (downward translational force) of the user A that the walking assisting device 1 bears via the seat portion 2 hardly act on the user A, and the legs rest 3, 3 acts on the ground through the annular members 36, 36 of the mounting parts 15, 15 of both legs. the

Therefore, in the full supporting force, the supporting force for supporting the gravity acting on the walking assisting device 1 and the load of the user A received by the walking assisting device 1 via the seat part 2 acts on both sides of the walking assisting device 1 . On leg support 3,3. The walking assistance device 1 takes up this supporting force via the leg supports 3 , 3 . Hereinafter, the supporting force borne by the walking assist device 1 is referred to as the assisting device borne supporting force. In other words, the supporting force borne by the assisting device is a support for supporting the entire weight of the walking assisting device 1 and the weight corresponding to the load received by the user A from the seat part 2 (a part of the weight of the user A) on the ground. force. In addition, when the user A stands on both legs (when the two foot mounting parts 15 of the walking assisting device 1 touch the ground), the supporting force borne by the assisting device is shared by the two leg supports 3, 3 (the supporting force borne by the assisting device A part of the support force is borne by one leg support 3, and the remaining support force is borne by the other leg support 3). At the same time, when the user A is standing on only one leg (when the other leg is a free leg), the support force borne by the auxiliary device is all borne by the leg support 3 on the side of the standing leg. Hereinafter, among the support forces borne by the auxiliary device, the support force borne by each leg support 3 (the support force acting on each leg support 3 ) is referred to as the leg support force, and the support force borne by the right leg support 3 is referred to as the right side support force. The support force of the leg support, the support force borne by the left leg support 3 is called the support force of the left leg support. The sum of the support force of the left leg support and the support force of the right leg support is consistent with the support force borne by the auxiliary device. the

On the other hand, the support force obtained by subtracting the support force borne by the auxiliary device from the full support force acts on the legs of the user A from the ground, and the user A bears the support force by his legs. Hereinafter, the supporting force borne by the user A in this way is referred to as the supporting force borne by the user. In other words, the supporting force borne by the user is a supporting force for supporting a weight on the ground that is equal to the amount of weight that the user A acts on the walking assist device 1 from the body weight of the user A. The weight of the load on the seating part 2. In addition, when the user A stands on both legs, the two legs of the user A share the user's support force (a part of the support force in the user's support force is borne by one leg, and the other leg is borne). remaining support). Simultaneously, when the user A stands on only one leg, the user bears all the supporting force on the one leg. Hereinafter, in the supporting force borne by the user, the supporting force borne by each leg (the supporting force acting on each leg from the ground) is called the supporting force of the user's leg, and the supporting force borne by the right leg is called the supporting force of the user's right leg. , the supporting force borne by the left leg is called the supporting force of the user's left leg. The sum of the support force of the user's left leg and the support force of the user's right leg is consistent with the support force borne by the user. In addition, the force with which the user A props the feet of each leg on the ground to support himself is called the pedaling force of the leg. The pedaling force of each leg is a force balanced with the supporting force of the user's leg. the

Supplementary description of the following content: Since the force sensor 30 provided on each leg frame 3 is arranged on the upper side of the third joint 14, the force for supporting the leg frame 3 is subtracted from the leg frame supporting force of the leg frame 3. The supporting force of the weight of the lower part of the force sensor 30 (eg, the leg attachment portion 15 ) acts on the force sensor 30 . The force sensor 30 measures the component force in the triaxial direction (or the component force in the biaxial direction) of the support force acting on the sensor 30 . In other words, the force acting on each of the force sensors 30 (which corresponds to the controlled force in the present invention) corresponds to the part borne by the leg frame 3 including the force sensor 30 among all supporting forces described below. , the entire supporting force is used to support the weight obtained by subtracting the sum of the weights of the lower parts of the force sensors 30 from the overall weight of the walking assistance device 1 and the load corresponding to the load on the seat part 2 by the user A. the weight of. Simultaneously, the summation of the supporting force measured respectively by two force sensors 30,30 is consistent with following all supporting forces (hereinafter, claiming that force sensor 30 is supporting force sensor 30), and described whole supporting force is used for supporting walking The total weight of the auxiliary device 1 is the weight obtained by subtracting the sum of the weights of the lower parts of the force sensors 30 and the weight corresponding to the load applied by the user A to the seat part 2 . In addition, the sum of the weights of the lower parts of the support force sensors 30 of the walking assistance device 1 is very small compared to the weight of the entire walking assistance device 1 . Therefore, the support force acting on each support force sensor 30 is almost equal to the leg support support force. Furthermore, each supporting force sensor 30 is provided close to the third joint 14 of the leg frame 3 provided with the supporting force sensor 30 . Therefore, the supporting force acting on the supporting force sensor 30 and the translational force acting on the calf frame 13 from the third joint 14 of the leg frame 3 (in the leg frame supporting force, it is transmitted from the ground to the calf via the third joint 14). The supporting force of frame 13) is almost equal. Hereinafter, the sum of the support force acting on each support force sensor 30 or the translational force acting on the calf support 13 from the third joint 14 of each leg support 3, the sum of the two leg supports 3, 3 is called the total lifting force . At the same time, the bearing amount of each leg support 3 in the total lifting force is called the total lifting force bearing amount. the

In addition, the sum of the forces acting on the MP sensor 38L and the heel sensor 39L of the left foot mounting part 15L is equivalent to the user's left leg supporting force (or left leg pedaling force), and acts on the right foot mounting part 15L. The sum of the forces of the MP sensor 38L and the heel sensor 39R of the portion 15R corresponds to the support force of the user's right leg (or the stepping force of the right leg). Moreover, in this embodiment, although the MP sensor 38 and the heel sensor 39 are set as a 1-axis force sensor, for example, a 2-axis force sensor or a 2-axis force sensor that can measure a translational force in a direction parallel to the bottom surface of the shoe body 33 may be used. 3-axis force sensor. The MP sensor 38 and the heel sensor 39 are preferably sensors capable of measuring at least a translational force in a direction perpendicular to the bottom surface of the shoe body 33 or the ground. the

Next, the control device of the walking assistance device 1 configured as described above will be described. the

FIG. 4 is a block diagram schematically showing the configuration (hardware configuration) of the control device 50 . As shown in the figure, the control device 50 includes an arithmetic processing device 51, drive circuits 52R and 52L for the motors 27R and 27L, a key switch 53 for setting the lifting force, a lifting control ON/OFF switch 54, and a power supply battery 55. , power supply circuit 57, wherein, arithmetic processing device 51 is made of microcomputer (CPU, RAM, ROM) and input, output circuit (A/D converter etc.); The target value of the lifting force of the user of the device 1 (acting on the upward translation force of the user A from the seat portion 2); lifting control ON/OFF switch 54 selects whether to generate the lifting force of the user; the power supply circuit 57 passes through the power supply A switch 56 (ON/OFF switch) is connected to the power supply battery 55. When the power switch 56 is turned ON (closed), the power supply battery 55 supplies power to each circuit 9, 52R, 52L. In addition, the key switch 53 for lifting force setting corresponds to target lifting force setting means in this invention. the

The control device 50 is fixed to the rear end of the seating part 2 or the plates 23R, 23L, etc. via a bracket (not shown). At the same time, a key switch 53 for setting the lifting force, a lifting control ON/OFF switch 54 and a power switch 56 are installed outside the outer case (not shown) of the control device 50 in an operable manner. In addition, the lifting force setting key switch 53 can be directly set the desired lifting force target value, or can selectively set a variety of target values prepared in advance by digital switches or multiple constitutes a selector switch. the

The MP sensors 38R, 38L, the heel sensors 39R, 39L, the supporting force sensors 30R, 30L, and the rotary encoders 28R, 28L are connected to the control device 50 via unillustrated wiring. The output signals of these sensors are input to the arithmetic processing unit 51 . Furthermore, operation signals (signals indicating the operating states of these switches) of the key switch 53 for lifting force setting and the lifting control ON/OFF switch 54 are also input to the arithmetic processing device 51 . In addition, in the control device 50 , unillustrated wires for energizing the motors 27R and 27L are respectively connected from the drive circuits 52R and 52L to the motors 27R and 27L. Furthermore, the arithmetic processing device 51 determines command values (hereinafter referred to as command current values) of the energizing currents of the electric motors 27R and 27L based on arithmetic processing (control processing) described later. And, by controlling the drive circuits 52R, 52L using the indicated current value, the arithmetic processing device 51 can control the torque generated by the electric motors 27R, 27L. the

In addition, the output signals (voltage signals) of the MP sensors 38R, 38L, heel sensors 39R, 39L, and support force sensors 30R, 30L can also be input to the control device 50 after being increased in amplitude by preamplifiers near these sensors. . At the same time, after the output signals of the MP sensors 38R, 38L, heel sensors 39R, 39L, and support force sensors 30R, 30L are increased in amplitude, the voltage values are A/D converted and then processed by the arithmetic processing device. the

As its main functional mechanism, the arithmetic processing device 51 includes the functional mechanism shown in the block diagram of FIG. 5 . This functional mechanism is a function realized by a program stored in the ROM. the

Referring to FIG. 5 , the arithmetic processing device 51 includes a right pedaling force measuring mechanism 60R and a left pedaling force measuring mechanism 60L, wherein the output signals of the MP sensor 38L and the heel sensor 39L of the right leg support 3R are input to the right pedaling force measuring mechanism 60R and the left pedaling force measuring mechanism 60L. The force measurement processing mechanism 60R; output signals of the MP sensor 38R and the heel sensor 39R of the left leg frame 3L are input to the left pedaling force measurement processing mechanism 60L. The right pedaling force measurement processing mechanism 60R measures the pedaling force of the right leg of the user A (the supporting force of the user's right leg) through the voltage value of the output signal of the MP sensor 38R and the heel sensor 39R. processing agency. Similarly, the left side stepping force measurement processing mechanism 60L is based on the magnitude of the stepping force of the left leg of the user A (the magnitude of the supporting force of the user's left leg) by the voltage value of the output signal of the MP sensor 38L and the heel sensor 39L. The body that performs measurement processing. However, these pedaling force measurement processing mechanisms 60R and 60L are one mechanism corresponding to the pedaling force measurement mechanism in the present invention. the

Meanwhile, the arithmetic processing unit 51 includes a right knee angle measurement processing unit 61R and a left knee angle measurement processing unit 61L to which output signals (pulse signals) of the rotary encoders 28R and 28L are input. These knee angle measurement processing mechanisms 61R and 61L are mechanisms for measuring the bending angles (displacement amounts of the second joints 12 ) of the corresponding leg frames 3 at the second joints 12 from the input signals. In addition, since the second joint 12 of each leg support 3 is equivalent to the knee joint of the leg support 3, the bending angle at the second joint is referred to as the knee angle hereinafter. Meanwhile, these knee angle measurement processing mechanisms 61R, 61L correspond to the joint displacement amount measurement mechanism in the present invention. the

In addition, the arithmetic processing device 51 includes a right supporting force measurement processing mechanism 62R and a left supporting force measuring processing mechanism 62L, wherein the output signal of the supporting force sensor 30R of the right leg support 3R and the output signal obtained by the right knee angle measurement processing The knee angle of the right leg support 3R measured by the mechanism 61R is input to the right support force measurement processing unit 62R; the output signal (output voltage) of the support force sensor 30L of the left leg support 3L The knee angle of the left leg frame 3L measured by the measurement processing unit 61L is input to the left support force measurement processing unit 62L. The right support force measurement processing mechanism 62R is a support force sensor that acts on the support force of the right leg support based on the input output signal of the support force sensor 30R and the measured value of the knee angle of the right leg support 3R. The support force on 30R, that is, the mechanism for measuring the total lifting force bearing amount of the right leg support 3R. Similarly, the left support force measurement processing mechanism 62L is based on the input output signal of the support force sensor 30L and the measured value of the knee angle of the left leg support 3L to support the support force acting on the left leg support. The supporting force on the force sensor 30L, that is, the above-mentioned total lifting force borne amount of the left leg frame 3L is a mechanism that performs measurement processing. However, these support force measurement processing mechanisms 62L, 62L correspond to the control object force measurement mechanism in this invention. the

In addition, the arithmetic processing device 51 is provided with a left and right target load determining means 63, the measurement values of the respective measurement processing means 60R, 60L, 61R, 61L, 62R, and 62L, the key switch 53 for setting the lifting force, and the lifting force setting means. An operation signal for controlling the ON/OFF switch 54 is input to the left and right target commitment determination means 63 . The left and right target burden determining means 63 is a mechanism that determines the target total lifting force as the target value of the total lifting force based on the input value and at the same time determines the following target value. The target value of the bearing amount of each leg frame 3 in the target total lifting force, that is, the target value of the total lifting force bearing amount of each leg frame 3 (hereinafter simply referred to as the control target value). However, this control target value corresponds to the target commitment amount in this invention (4th invention). the

Furthermore, the arithmetic processing device 51 includes a right feedback operation amount determining mechanism 64R, a left feedback operation amount determining mechanism 64L, a right feedforward operation amount determining mechanism 65R, and a left feedforward operation amount determining mechanism 65L, wherein the The total lifting force bearing amount of the right leg frame 3R measured by the right supporting force measurement processing means 62R and the control target value of the right leg frame 3R determined by the left and right target load amount determining means 63 are input to the right side. Feedback operation amount determination mechanism 64R; the total lifting force commitment of the left leg frame 3L measured by the left support force measurement processing mechanism 62L and the left leg frame 3L determined by the left and right target load determination mechanism 63 The control target value of the left leg support 3R measured by the right side support force measurement processing mechanism 62R is input to the left feedback operation amount determination mechanism 64L; The control target value of the right leg frame 3R determined by the determining means 63 and the knee angle of the right leg frame 3R measured by the right knee angle measurement processing means 61R are input to the right feedforward operation amount determining means 65R; The total lifting force bearing amount of the left leg frame 3L measured by the left supporting force measurement processing mechanism 62L, the control target value of the left leg frame 3L determined by the left and right target load amount determining means 63, and The knee angle of the left leg frame 3L measured by the left knee angle measurement processing unit 61L is input to the left feedforward operation amount determination unit 65L. Each feedback operation amount determining means 64 calculates the feedback operation amount (the feedback component to the indicated current value of each motor 27) based on the input measured value of the total lifting force bearing amount and its deviation from the control target value. A mechanism that makes the deviation converge to 0 under the prescribed feedback control mode. Simultaneously, each feed-forward operation amount determination mechanism 65 calculates the feed-forward operation amount (relative to the indicated current value of each motor 27) based on the input measured value of the total lifting force bearing amount, the control target value and the knee angle measured value. Feedforward component) to make the measured value of the total lifting force commitment become the control target value under the specified feedforward control mode. the

In addition, the arithmetic processing device 51 includes an addition processing unit 66R and an addition processing unit 66L, wherein the addition processing unit 66R combines the feedback operation amount calculated by the right feedback operation amount determination unit 64R with the feedback operation amount calculated by the right feedforward operation amount determination unit 65R. The feedforward operation amount of the left leg support 3R is obtained by summing the indicated current value for the motor 27R of the right leg support 3R; The feed-forward operation amounts calculated by the determining means 65L are summed up to obtain an indicated current value for the motor 27L of the left leg link 3L. the

In addition, the said feedback operation amount determination means 64R, 64L, the feedforward operation amount determination means 65R, 65L, and addition processing means 66R, 66L correspond to the driver control means in this invention. the

The above is a rough calculation processing function of the calculation processing device 51 . the

Next, the detailed processing description including the arithmetic processing device 51 will describe the control processing of the control device 50 according to the present embodiment. When the walking assistance device 1 according to the present embodiment is used, the driving force is not applied to the second joint 12 of each leg link 3 when the power switch 56 is set to OFF. Therefore, each joint 10, 12, 14 is in a freely movable state. In this state, each leg frame 3 is folded by its own weight. In this state, after installing each foot mounting portion 15 on each foot of the user A, the user A or an accompanying assistant lifts the seat portion 2 and places it under the crotch of the user A. the

Next, when the power switch 56 is turned ON, power is supplied to each circuit of the control device 50 to activate the control device. Then, when the control device 50 is activated, the arithmetic processing device 51 executes the processing described below in a predetermined control processing cycle. the

In each control processing cycle, the arithmetic processing device 51 first executes the processing of the above-mentioned pedaling force measurement processing means 60R, 60L. This processing will be described with reference to FIG. 6 . FIG. 6 is a block diagram showing the processing flow of the pedaling force measurement processing means 60R, 60L. In addition, the processing methods of each of the pedaling force measurement processing mechanisms 60R and 60L are the same. Therefore, the left pedaling force measurement processing mechanism 60L is shown in parentheses in FIG. 6 . the

A representative description will be given of the right pedaling force measurement processing mechanism 60R. First, the measured value of the MP sensor 38R of the leg support 3R (the measured value of the force represented by the output voltage value of the MP sensor 38R) and the measured value of the heel sensor 39R (the measured value of the force represented by the output voltage value of the heel sensor 39R) value) are passed through the low-pass filter in S101 and S102 respectively. The low-pass filter can remove high-frequency components such as noise from the measured values of these sensors 38R and 39R, and the cutoff frequency is, for example, 100 Hz. the

Next, the output values of these low-pass filters are summed up in S103. Thus, the provisional measurement value FRF_p_R of the pedaling force of the user A's right leg can be obtained. The provisional measurement value FRF_p_R includes an error component of the shoe body strap tightness following the right foot mounting portion 15R. the

Therefore, in this embodiment, and in s104 , the measured value FRF_R of the stepping force of the user A's right leg is finally obtained by performing conversion processing on the provisional measured value FRF_p_R. The conversion processing in S104 is performed following the graph shown in FIG. 7 . That is, when FRF_R is below the predetermined first threshold FRF1, the measured value FRF_R takes a value of 0. Accordingly, it is possible to prevent a slight error portion accompanying the shoe body strap tightening degree of the foot mounting portion 15R from being calculated as the measured value FRF_R. Moreover, when the temporary measurement value FRF_p_R is larger than the first threshold FRF1 and smaller than the second threshold FRF2 (>FRF1), as FRF_p_R increases, the value of the measurement FRF_R increases linearly. Furthermore, when FRF_p_R exceeds the second threshold FRF2, the value of FRF_R is kept at a predetermined upper limit (the value of FRF_R when FRFF_p_R is the same as the second threshold FRF2). In addition, the reason for setting the upper limit value of FRF_R will be described later. the

The above is the description of the processing of the right pedaling force measurement processing means 60R. The processing of the left pedaling force measurement processing means 60L is also the same. the

Next, the arithmetic processing unit 51 performs the processing of the knee angle measurement processing means 61R, 61L and the processing of the supporting force measurement processing means 62R, 62L step by step. These processes will be described with reference to FIGS. 8 and 9 . FIG. 8 is a block diagram showing the processing flow of the knee angle measurement processing means 61R, 61L and the processing flow of the supporting force measurement processing means 62R, 62L. In addition, the processing methods of the knee angle measurement processing mechanisms 61R and 61L are the same. Meanwhile, the processing methods of the supporting force measurement processing mechanisms 62R and 62L are also the same. Therefore, the left knee angle measurement processing mechanism 61L and the left support force measurement processing mechanism 62L are shown in parentheses in FIG. 8 . the

The processing of the right knee angle measurement processing unit 61R and the right support force measurement processing unit 62R will be typically described below. First, the right knee angle measurement processing unit 61R performs S201 and S202 processes to obtain the measured value θ1_R of the knee angle of the right leg frame 3R (bending angle of the leg frame 3R at the second joint 12R). In S201 , the provisional measurement value θ1p_R of the knee angle of the leg frame 3R is calculated from the output of the rotary encoder 28R. the

Referring to FIG. 9 , in this embodiment, the angle θ1_R formed by the line segment S1 and the line segment S2 is measured and used as the knee angle of the right leg support 3R, wherein the line segment S1 is the first joint 10R connecting the leg support 3R. The center point P (the rotation center point P of the thigh frame 11R swinging back and forth. Hereinafter referred to as the front and rear swing center point P) and the line segment of the center point of the second joint 12R; the line segment S2 connects the center point of the second joint 12R and the third joint. Center point of joint 14R. The same applies to the knee angle of the left leg brace 3L. In addition, in FIG. 9, the structure of the main part of the leg support 3 is shown schematically. the

At this time, in the above-mentioned S201, the thigh frame 11R and the calf frame 13R of the leg frame 3R are in a state when they are in a predetermined posture (for example, the posture state in FIG. The rotational position of the second joint 12R is a standard, and the rotational amount relative to the standard rotational position is measured based on the output signal of the rotary encoder 28R (rotational angle variation. It is proportional to the rotational amount of the rotor of the motor 27R). Then, the measured rotation amount of the second joint 12R is added to the knee angle value of the leg frame 3R at the standard rotation position (which is pre-recorded and stored in a memory not shown), and the obtained The value of is taken as the temporary measured value θ1p_R. the

Since the provisional measurement value θ1p_R contains high-frequency noise components, the knee angle measurement value θ1p_R of the leg support 3R is finally obtained by passing the θ1p_R through a low-pass filter in S202. the

The above is the description of the processing of the right knee angle measurement processing unit 61R. The processing of the left knee angle measurement processing unit 61L is also the same. the

The following is supplemented: In this embodiment, the angle θ1 formed by the line segments S1 and S2 is measured and used as the knee angle of the leg frame 3 because it is used in the processing of the left and right target load determining means 63 described in detail later. to this angle θ1. At this time, in the walking assistance device 1 according to the present embodiment, the angle formed by the shaft center of the thigh frame 11 of each leg frame 3 and the line segment S1 is constant. Therefore, in each knee angle measurement processing mechanism 61, for example, the angle formed by the axis line of the thigh frame 11 of the leg frame 3 and the line segment S2 of the calf frame 13 may be obtained in advance and used as the angle of the leg frame 3. , and the angle θ1 is obtained from the knee angle in the processing of the left and right target commitment determining means 63 described later. the

After obtaining the knee angle measurement value θ1_R of the leg frame 3R as described above, the process of the right support force measuring mechanism 62R is executed in S203, and the knee angle measurement value θ1_R obtained in S202 and the measured value of the support force sensor 30R (support The 2-axis force measurement value represented by the voltage value of the output signal of the force sensor 30R) calculates the measured value Fankle_R of the support force acting on the support force sensor 30R (that is, the total lifting force borne by the leg support 3R ). The details of this processing will be described with reference to the aforementioned FIG. 9 . the

The support force (total lifting force bearing amount) Fankle_R acting on the support force sensor 30R of the leg support 3R is almost equal to the translational force acting from the third joint 14R of the leg support 3R to the lower leg support 13R as described above. And, this translational force is almost equal to the vector (the vector with the line segment S3 as the line of action) from the third joint 14R toward the center point P of the back-and-forth swing of the leg frame 3R. Therefore, in the walking assistance device 1 of the present embodiment, the orientation of Fankle_R is parallel to the line segment 3 connecting the center point of the third joint 14 of the leg frame 3R and the center point P of the forward and backward swing. the

Here, due to the influence of the frictional force at the first to third joints 10, 12, and 14, gravity, acceleration and deceleration during walking, and the total lifting force of the walking assistance device 1, strictly speaking, Fankle_R The orientation of may not be completely parallel to the line segment S3. However, since these effects are relatively small, they can be ignored in this embodiment. the

On the other hand, the support force sensor 30R measures the force Fz in the z-axis direction and the force Fx in the x-axis direction. As shown in the figure, the z-axis direction is perpendicular to the surface (upper surface or lower surface) of the support force sensor 30R. ; The x-axis is perpendicular to the z-axis and parallel to the surface supporting the force sensor 30R. The x-axis and the z-axis are coordinate axes fixed to the support force sensor 30R, and are axes parallel to the plane including the arc of the guide rail 22 . At this time, Fz and Fx measured are the z-axis direction component force and the x-axis direction component force of Fankle_R, respectively. Therefore, as shown in the figure, when the angle between Fankle_R and the z-axis is set as θk, Fankle_R can be calculated from the measured values of Fz and Fx and θk from the formula (1). the

Fankle_R＝Fx sinθk+Fz cosθk...(1)

Meanwhile, the angle θk is obtained by the following method. That is, when the angle formed by the line segment S2 and the line segment S3 (=the angle formed by the direction of Fankle_R and the line segment S2) is set to θ2, the line segments S1, S2 in a triangle with the line segments S1, S2, and S3 as three sides The respective lengths L1 and L2 are constant values (preset and known numerical values). Furthermore, the angle θ1 formed by the line segments S1 and S2 is the measured value θ1_R obtained by the right knee angle measurement processing mechanism 61R as described above. Therefore, the angle θ2 can be obtained through geometrical calculations according to the respective lengths L1, L2 of the line segments S1, S2 (these values are pre-recorded and stored in the memory) and the measured value θ1_R of the angle θ1. the

Specifically, in a triangle whose three sides are the line segments S1 , S2 , and S3 , relational expressions of the following expressions (2) and (3) hold. Among them, L3 is the length of line segment S3. the

L3 ² ＝L1 ² +L2 ² -2·L1·L2·cosθ1...(2)

L1 ² ＝L2 ² +L3 ² -2·L2·L3·cosθ2...(3)

Therefore, the value of L3 can be calculated according to the values of L1 and L2 and the measured value of angle θ1 through formula (2), and the angle θ2 can be calculated through formula (3) based on the calculated values L3, L1 and L2. the

Furthermore, when the angle formed by the z-axis and the line segment S2 is set to θ3, this angle θ3 is a predetermined constant value because it is an attachment angle of the bearing force sensor 30 to the calf support 13 . Then, the angle θk required for the calculation of the formula (1) can be obtained by subtracting the angle θ2 calculated as above from the constant value angle θ3 (this value is stored in a memory not shown in advance). the

Therefore, in the present embodiment, through the processing of S203 of the right supporting force measurement processing unit 62R, the formula (1 ) can obtain the measured value Fankle_R of the total lifting force borne by the right leg support 3R. the

The above is the description of the detailed processing in S203 of the right support force measurement processing means 62R. The processing of the left support force measurement processing mechanism 62L is also the same. the

In addition, in this embodiment, although the support force sensor 30 is set as a 3-axis force sensor or a 2-axis force sensor, the measurement of the total lifting force borne by each leg support can be obtained according to the above formula (1). value Fankle, but the measurement value Fankle can be obtained even if a single-axis force sensor is used as the support force sensor 30 . For example, when the supporting force sensor 30 is a sensor that measures only the force Fx in the x-axis direction in FIG. 9 , the measurement value Fankle can be obtained according to the following equation (4). In addition, when the support force sensor 30 is a sensor that measures only the force Fz in the z-axis direction in FIG. 9 , the measured value Fankle can be obtained from the following equation (5). the

Fankle＝Fx/sinθk...(4)

Fankle＝Fz/cosθk...(5)

However, when these formulas (4) or (5) are used, when the angle θk is close to 0 degrees or 90 degrees, the numerical accuracy of Fankle becomes poor. Therefore, it is most preferable to obtain the measured value of Fankle by the above formula (1). the

In addition, the measured value Fankle can also be obtained from the square root of the sum of the square of Fx and the square of Fz. In this case, the measured value θ1 of the knee angle is unnecessary. the

Supplementary explanation of the following: the processing of the measurement processing units 60 , 61 , and 62 described above is not necessarily performed sequentially, and may be performed in parallel by time division or the like. However, when θ1 is used in the processing of the supporting force measurement processing means 62R, 62L, the processing of the knee angle measurement processing means 61R, 61L must be performed before the processing of the supporting force measurement processing means 62R, 62L. the

In addition, in this embodiment, the support force sensor 30 (second force sensor) is interposed between the third joint 14 and the calf frame 13 (precisely, the upper leg frame 13a), wherein the support force sensor 30 is used to measure the total lifting force bearing capacity of each leg support 3 . However, the supporting force sensor may be interposed between the third joint 14 and the foot mounting part 15 (for example, between the third joint 14 and the connection part 34 of the foot mounting part 15). At this time, the rotation angle of the third joint 14 is measured, and by performing coordinate transformation on the supporting force measured by the supporting force sensor between the third joint 14 and the foot mounting part 15, the force acting on the calf frame 13 from the third joint 14 can be measured. supporting force. the

Subsequently, the arithmetic processing device 51 executes the processing of the left and right target commitment determining means 63 . This processing will be described in detail below with reference to FIG. 10 . FIG. 10 is a block diagram showing the processing flow of the left and right goal commitment determination means 63 . the

First, in S301, the measured value Fankle_R of the total lifting force bearing amount of the right leg frame 3R obtained by each supporting force measuring mechanism 62 as described above is added to the total lifting force of the left leg frame 3L. Take the measured value Fankle_L of the load to calculate the total lifting force Fankle_t. As mentioned above, this lifting force Fankle_t is equivalent to the support force acting on each support force sensor 30, or the translation force of the leg supports 3, 3 acting on the lower leg support 13 from the third joint 14 of each leg support 3. The sum of the measured values on . In addition, the total lifting force Fankle_t is almost equal to the bearing force assumed by the auxiliary device. the

Next, one of the value after subtracting the output value of S307 and the output value of S312 described later and the total lifting force setting value corresponding to the following lifting force (target lifting force) from the total lifting force Fankle_t At S302, it is selectively output according to the operation signal of the lifting control ON/OFF switch 54 (the switch 54 shows whether the signal is ON or OFF), and the lifting force (target lifting force) is determined by the The lifting force is set with the silver key switch 53, and the force acting on the user A from the seat part 2 is described. At this time, in this embodiment, when the user A wishes to receive the lifting force from the seat portion 2, the lifting control ON/OFF switch 54 is turned ON, and at other times the lifting control ON/OFF switch 54 is turned ON. is operated as OFF. And, when the lifting control ON/OFF switch 54 is OFF at S302, the total lifting force Fankle_t is selected for output. At the same time, when the lifting control ON/OFF switch 54 is ON, the total lifting force setting value is selected for output. the

Supplement the following content: that is, the total lifting force setting value is the force after adding the following supporting force to the lifting force setting value of the key switch 53, wherein the supporting force is used to support The total weight of the walking assist device 1 is the force of the weight obtained by subtracting the total weight of the lower parts of the supporting force sensors 30 (that is, the supporting force that is balanced with the gravitational force generated by the subtracted weight). The size of the supporting force is recorded and stored in a memory not shown in the figure. In addition, the total weight of the lower portion of the support force sensor 30 is considerably smaller than the overall weight of the walking assistance device 1 . Therefore, the total lifting force setting value can be defined as a force that is added to the lifting force setting value (target lifting force) to support the entire weight of the walking assistance device 1 (equilibrium with the gravitational force acting on the walking assist device 1 as a whole) the power of magnitude. Alternatively, it may also be set so that the total lifting force set value can be directly inputted through the operation of the key switch 53 . the

Next, the output of S302 is passed through a low-pass filter at S303, and the target total lifting force is determined accordingly. The low-pass filter of this S303 is when the output of S302 changes abruptly (when the total lifting force setting value is changed, or the output of S302 and the output value of S307 described later are subtracted from the total lifting force Fankle_t and the value after the output value of S312, the replacement between the total lifting force setting values, etc.) to prevent the target total lifting force from abruptly changing, and can even be used to avoid lifting from the seat part 2 acting on the user A The force produces a sudden change. The cutoff frequency of this low-pass filter is, for example, 0.5 Hz. In addition, the processing from S301 to S303 corresponds to the total target lifting force determination means in the present invention. the

Next, at S304, a step for raising the target is determined according to the magnitude of the right leg treading force measurement value FRF_R and the magnitude of the left leg treading force measurement value FRF_L obtained by each treading force measurement processing mechanism 60 as described above. Power is distributed to the proportioning of each leg support 3 on the left and right sides. The proportion is composed of the right proportion allocated to the right leg support 3R and the left proportion allocated to the left leg support 3L proportion, and the sum of the two proportions is 1. the

At this time, the ratio on the right is the ratio of the measured value FRF_R to the sum of the measured value FRF_R and the measured value FRFL, which is determined as FRF_R/(FRF_R+FRF_L). Similarly, the ratio on the left is the ratio of the measured value FRF_L to the sum of the measured value FRF_R and the measured value FRF_L, that is, it is determined as FRF_L/(FRF_R+FRF_L). In this case, when one of the legs of user A is a standing leg and the other leg is a free leg (that is, a state supported by one leg), the ratio corresponding to the free leg is 0, and the ratio corresponding to the standing leg is 0. The ratio of legs is 1. In addition, the processing of S304 may be set to be performed in parallel with the processing of S301 to S303 described above. the

Here, the reason why the upper limit value is set to the pedaling force measurement value FRF of each leg in the conversion process of S104 (see FIG. 6 ) of each pedaling force measurement processing means 60 will be described. When user A's legs are in a standing state (that is, in a state in which both legs are supported), the provisional measurement value FRF_p of the pedaling force of each leg generally does not change smoothly, but tends to fluctuate frequently. In this case, if the ratio of left and right is determined according to the provisional measurement value FRF_p, the ratio will change frequently, so that the contribution ratio of each leg frame 3 in the target total lifting force tends to change frequently. As a result, slight fluctuations in the lifting force acting on the user A from the seating portion 2 are likely to occur. Furthermore, there is a possibility that the user A may feel uncomfortable. Therefore, in this embodiment, the upper limit value of the pedaling force measurement value FRF of each leg is set, and the situation such as frequent changes in the ratio of left and right can be prevented under the state when the legs are supported. At this time, in the state when the two legs are supported, basically except for the beginning stage and the end stage, the left-right ratio is maintained at 1/2 so that the left-right ratio is stable. the

In addition, the measured value FRF_R(L) can also be obtained according to the graph in FIG. 7, wherein the graph only has a threshold value FRF1, and the temporary measured value of the pedaling force of each leg of user A is set. When FRF_p_R(L) is greater than the threshold value FRF1, the temporary measured value FRF_p_R(L) of the pedaling force increases linearly. Thresholds FRF1 and FRF2 used to obtain the graph of FRF_p_R(L) based on the provisional measurement value FRF_p can correspond to user A's preferred lifting force feeling, the weight of the walking assistance device 1 and the computing power of the control device 50, etc. to make an appropriate decision. the

Returning to the description of FIG. 10 , the processes of S305 and S310 are executed next. In addition, these processes of S305 and 310 may be performed in parallel with the processes of S301 to S303 or the process of S304. the

The process of S305 is a process of obtaining the operating force for generating the spring-like restoring force of the right leg link 3R, and the process of obtaining the operating force of generating the spring-like restoring force of the left leg link 3L. Hereinafter, these operating forces are referred to as spring restoring forces. the

Since the processing method of S305 is the same as that of S310, the processing of S305 of the right leg link 3R will be typically described below with reference to FIG. 9 . the

Through S305 processing, first use the knee angle measurement value θ1_R of the leg support 3R and calculate the length L3 of the line segment S3 in FIG. The length L3 of the line segment S3 of the front-back swing center point P, wherein the knee angle measurement value θ1_R of the leg frame 3R is obtained by processing the right knee angle measurement processing unit 61R as described above. And, the following value is obtained as the spring restoring force of the right leg support 3R, and the value is obtained by subtracting the preset standard value L3S from the calculated L3 (L3-L3S) and multiplied by the specified value. The value of the spring constant k. the

That is, the spring restoring force can be calculated by the following formula (6). the

Spring restoring force＝k·(L3-LS3)...(6) 

The same applies to the processing of S310 described above for the left leg link 3L. The spring restoring force of each leg frame 3 calculated by the method described above corresponds to the support force (required value of the support force) that should additionally act on the walking assist device 1 in order to achieve the following purpose: In order to return the posture of the leg frame 3 to a posture in which the length L3 of the line segment S3 in FIG. 9 matches the standard value L3S. the

In addition, in the present embodiment, although the spring restoring force is obtained by the proportional control method which is the feedback control method, it may be obtained by other methods such as the PD control method. Also, the length L3 of the line segment S3 is equal to the value obtained by adding a constant offset value to the distance between the third joint 14 of each leg frame 3 and the seat portion 2 . Therefore, calculating the spring restoring force so that the deviation (L3-L3S) is close to 0 is equivalent to calculating the spring restoring force so that the distance between the third joint 14 of each leg support 3 and the seat part 2 is equal to the predetermined standard value ( The value obtained by subtracting the offset value from L3S) is close to zero. the

Next, the processes of S306 to S309 of the right leg link 3R and the processes of S311 to S314 of the left leg link 3L are executed. In the process of S306 to S309 of the right leg support 3R, the target total lifting force obtained in S303 is multiplied by the right ratio. In this way, the basic target value of the total lifting force bearing amount is determined as the bearing amount of the right leg link 3R in the target total lifting force. The basic target value refers to the value of the sum of the bearing amount of the right leg frame 3R in the following target lifting force and the bearing amount of the right leg frame 3R in the supporting force for supporting the following weight, wherein The target lifting force is the target value of the lifting force acting on the user A from the seat portion 2; the weight refers to the total weight of the lower part of each supporting force sensor 30 subtracted from the overall weight of the walking assistance device 1 weight (or the overall weight of the walking assist device 1). the

And, at S307, the right-side ratio is multiplied by the spring restoring force obtained at S305. And, by adding the multiplied numerical value (which is equivalent to the correction amount of the target bearing amount in the present invention) to the basic target value of the total lifting force bearing amount of the right leg support 3R at S308, it can be obtained The temporary target value Tp_Fankle_R of the total lifting force bearing amount of the right leg frame 3R. Then, by passing this provisional target value Tp_Fankle_R through the low-pass filter in S309, the control target value T_Fankle_R, which is the target value of the total lifting force bearing amount of the right leg link 3R, can finally be obtained. The low-pass filter of S309 is a device for removing noise components accompanying the variation of the knee angle θ1. Its cut-off frequency is, for example, 15 Hz. the

Similarly, in the processing from S311 to S314 of the left leg support 3L, first at S311, the left ratio is multiplied by the target total lifting force obtained in S303. In this way, the basic target value of the total lifting force bearing amount is determined as the bearing amount of the left leg link 3L in the target total lifting force. The basic target value refers to the value of the sum of the bearing amount of the left leg frame 3L in the following target lifting force and the bearing amount of the left leg frame 3L in the supporting force for supporting the following weight, wherein The target lifting force is the target value of the lifting force acting on the user A from the seat portion 2; the weight refers to the total weight of the lower part of each supporting force sensor 30 subtracted from the overall weight of the walking assist device 1 weight (or the overall weight of the walking assist device 1). the

Furthermore, at S312, the left-side ratio is multiplied by the spring restoring force obtained at S310. And, by adding the multiplied numerical value (which is equivalent to the correction amount of the target bearing amount in the present invention) to the basic target value of the total lifting force bearing amount of the left leg support 3L at S313, it can be obtained The temporary target value Tp_Fankle_L of the total lifting force bearing amount of the left leg frame 3L. Then, by passing this provisional target value Tp_Fankle_L through the low-pass filter in S314, the control target value T_Fankle_L, which is the target value of the total lifting force bearing amount of the left leg link 3R, can finally be obtained. For example, the output target total lifting force of S303 is 200N (Newton), when the left and right ratio (S304) corresponding to user A's left and right pedaling force is 0.4:0.6, then the output of S306 is 120N, and the output of S311 is 80N. the

The above is the process of determining the target commitment amount. As described above, the respective ratios of the control target values T_Fankle_L, T_Fankle_R of the left and right leg mounts 3 are basically determined to be the same ratio as the ratio of the user A's left and right pedaling forces. Furthermore, the spring restoring forces of the left leg frame 3L and the right leg frame 3R are added to the control target values T_Fankle_L, T_Fankle_R, respectively. In addition, the sum of the spring return force added to the control target value T_Fankle_L and the spring return force added to the control target value T_Fankle_R is the weighted average of the spring return forces calculated by S305 and S310 respectively, wherein the ratio of left and right is used as a weighting coefficient . Therefore, the sum of the control target values T_Fankle_L and T_Fankle_R is the value obtained by adding the weighted average value of the spring restoring force to the target total lifting force determined in S303. the

In addition, the processes of S304, S306, and S311 correspond to the allocation means in the present invention. the

After executing the processing of the left and right target commitment determination means 63 according to the above method, the arithmetic processing device 51 executes the processing of the feedback operation amount determination means 64R, 64L and the feedforward operation amount determination means 65R, 65L sequentially or in parallel. the

The processing of the feedback operation amount determining means 64R, 64L will be described with reference to FIG. 11 . FIG. 11 is a block diagram showing the processing flow of the feedback operation amount determining means 64R, 64L. In addition, since the methods of the feedback operation amount determination means 64R and 64L are the same, the left feedback operation amount determination means 64L is shown in parentheses in FIG. 11 . the

The processing of the right feedback operation amount determining means 64R will be typically described below. Firstly, the measured value T_Fankle_R of the total lifting force bearing amount of the right leg support 3R determined by the left and right target bearing amount determination mechanism 63 and the measured value T_Fankle_R measured by the right side supporting force measurement processing mechanism 62 are calculated in S401. The deviation value (T_Fankle_R-Fankle_R) between the measurement value Fankle_R of the total lifting force borne amount of the right leg frame 3R. Then, at S402 and S403, the gain coefficients Kp and Kd are respectively multiplied by the deviation value. Moreover, the operation result of S403 is differentiated at S404 ("s" in the figure refers to a differentiation operator), and the differential value is added to the operation result of S402 at S405. Thus, the current manipulated variable Ifb_R of the right electric motor 27 is calculated so that the deviation value (T_Fankle_R−Fankle_R) converges to zero by the PD control method which is the feedback control method. The operation amount Ifb_R is a feedback component of the indicated current value of the right motor 27 . the

At this time, in the present embodiment, the values of the gain coefficients Kp, Kd are set at S406 to be variable corresponding to the measured value θ1_R of the knee angle of the leg frame 3R. This is because the sensitivity to the change in the lifting force of the seat part 2 with respect to the current change (torque change) of the motor 27R changes according to the knee angle of the leg frame 3R. At this time, the greater the knee angle θ1_R (the straighter the leg frame 3R is stretched), the higher the sensitivity to the change in the lifting force of the seat part 2 with respect to the current change (torque change) of the motor 27R. Therefore, at S406, based on the data table (not shown), basically, the values of the gain coefficients Kp and Kd are decreased to be smaller as the knee angle measurement value θ1_R of the leg frame 3R is larger. Gain coefficient Kp, Kd value. the

The above is the processing of the right feedback operation amount determining means 64R. The processing of the left feedback operation amount determining means 64L is also the same. In addition, in this embodiment, by using the PD control method which is a feedback control method, it becomes possible to control a lifting force stably at high speed. However, a feedback control method other than the PD control method may also be used. the

Next, the processing of the feedforward operation amount determination means 65R and 65L will be described with reference to FIG. 12 . FIG. 12 is a block diagram showing the processing flow of the feedforward operation amount determining means 65R, 65L. In addition, since the processing methods of the feedforward operation amount determining means 65R and 65L are the same, in FIG. 12 , the left feedforward operating amount determining means 65L is shown in parentheses. the

The processing of the right feedforward operation amount determining means 65R will be typically described below. At S501, the knee angle measurement value θ1_R of the leg frame 3R measured by the knee angle measurement processing mechanism 61R is differentiated to calculate the angular velocity ω1_R of the bending angle of the second joint 12 of the leg frame 3R. And, at S502, the cable angle of the leg support 3R is calculated using the knee angle measurement value θ1_R of the leg support 3R and the measurement value Fankle_R of the total lifting force bearing amount of the leg support 3R measured by the supporting force measurement processing device 62R. 32a, 32b Actual pulling force Actual pulling force T1. The calculation process of the actual tension T1 will be described with reference to FIG. 13 . In addition, in FIG. 13, the leg support 3 is described schematically. Meanwhile, in FIG. 13, the same elements as those in FIG. 9 are given the same reference numerals. the

First, the component Fankle_a perpendicular to the line segment S2 of the total lifting force bearing amount measurement value Fankle_R of the leg frame 3R is calculated from the following equation (7). the

Fankle_a＝Fankle_R sinθ2...(7)

In addition, the angle θ2 is the angle formed by Fankle_R and the line segment S2. As explained with reference to the above-mentioned FIG. , (3)). the

Then, as shown in the following equation (8), the moment M1 generated on the second joint 12 (knee joint) due to Fankle_R can be calculated by multiplying the length L2 of the line segment S2 by the Fankle_a obtained by the above method. the

M1＝Fankle_a L2...(8)

The moment generated on the pulley by the actual tension T1 of the cables 32a, 32b is balanced with said moment M1 in steady state. Therefore, the actual tensile force T1 is calculated by dividing M1 by the effective radius r of the pulley 31 as shown in the following formula (9). the

T1＝M1/r...(9)

The above is the detailed content of the processing in S502. the

Returning to the description of FIG. 12 , next, at S503 , the target tension T2 of the cables 32 a and 32 b of the leg support 3R is calculated. The target tension T2 is the tension to be generated on the cables 32a and 32b in accordance with the control target value of the leg frame 3R (the target value of the total lifting force commitment) determined by the processing of the left and right target commitment determining means 63 . The calculation of the target tension T2 is the same as the calculation process of S502. More specifically, by substituting the Fankle_R on the right side of the formula (7) with the control target value T_Fankle_R of the leg frame 3R determined by the processing of the left and right target load determining means 63, the resultant value of the control target value T_Fankle_R is calculated. The components perpendicular to the line segment S2 (refer to Figure 1_3). Then, the target moment of the second joint 12 of the leg link 3R is calculated by using this calculated component as a substitute for Fankle_a on the right side of the formula (8). Then, the target tension T2 of the cables 32a and 32b is calculated by using this target moment as a substitute for the right-hand side M1 of the formula (9). the

The above is the processing of S503. the

After the processing from S501 to S503 as described above is performed, at S504, the angular velocity ω1_R of the second joint 12, the actual tension T1 and the target tension T2 of the cables 32a and 32b calculated by the above method are used to pass the prescribed feedforward processing. To determine the current operation amount Iff_R of the motor 27R. The manipulated variable Iff_R is a feedforward component of the indicated current value of the motor 27R. the

In the process of S504, the operation amount Iff_R is calculated by the formula expressed by the following formula (10). the

If_R＝B1 T2+B2 ω1_R+B3 sgn(ω1_R)...(10)

The conditions are: B2＝b0+b1·T1; B3＝d0+d1·T1

Here, B1 in the formula (10) is a constant coefficient, and B2 and B3 are coefficients representing a linear function of the actual tension T1 as described in the conditions of the formula (10). In addition, b0, b1, d0, and d1 are constants. Meanwhile, sgn() represents a symbolic function. the

This equation (10) is an equation expressing the relationship between the current of the motor 27 , the tension of the cables 32 a and 32 b , and the angular velocity ω1 of the second joint 12 . The first term on the right side of formula (10) is the proportional term of the pulling force, and the second term is the term equivalent to the viscous friction force between the cables 32a, 32b and the pulley 31 or the rubber tube (the protective tube of the cables 32a, 32b). The three terms are terms corresponding to the kinetic friction force between the cables 32a, 32b and the pulley 31 or the rubber tube (protective tube for the cables 32a, 32b). In addition, a term corresponding to the angular velocity of the second joint 12 (that is, a term corresponding to the inertial force) may be added to the right side of the formula (10). the

Supplement the following content: the constants B1, b0, b1, d0, and d1 used in the operation of formula (10) are identified in advance by making the square value of the difference between the value on the left and the value on the right of formula (10) the smallest Algorithm for experimental identification. In addition, the recognized constants B1, b0, b1, d0, and d1 are recorded and stored in a memory not shown, and are used when the walking assistance device 1 operates. the

The above is the processing of the right feedforward operation amount determining means 65R. The processing of the left feedforward operation amount determining means 65L is also the same. the

Referring to FIG. 5 , as described above, after calculating the current manipulated quantities Ifb_R, Ifb_R of the motor 27R and the current manipulated quantities Ifb_L, Ifb_L of the motor 27L, the arithmetic processing device 51 adds the manipulated quantities Ifb_R and Ifb_R through the addition processing mechanism 66R. Thus, the instructed current value of the motor 27R is determined. At the same time, the arithmetic processing device 51 adds the operation amount Ifb_L and Iff_L through the addition processing unit 66L. Thus, the instructed current value of the motor 27L is determined. And the computing device 51 outputs these indicated current values to the drive circuit 52 of the motor 27 respectively. At this time, the drive circuit 52 energizes the motor 27 according to the given instruction current. the

The control processing of the arithmetic processing unit 51 described above is executed at a predetermined cycle. Accordingly, the measured value Fankle of the actual total lifting force bearing capacity of each leg support 3 will be consistent with the control target value T_Fankle corresponding to the leg support 3, and the torque generated by the motor 27, and even the leg support 3 The driving force of the second joint 12 (knee joint) is operated. the

In the first embodiment described above, the line of action of the supporting force (translational force) transmitted from the third joint 14 of each leg frame 3 to the calf frame 13 passes through the center point of the third joint 14 The straight lines of the front-back swing center point P are almost equal, wherein the front-back swing center point P is located above the seat part 2 within the width in the front-back direction of the contact surface between the seat part and the user A. In addition, each leg frame 3 can freely swing back and forth relative to the seat portion 2 with the front-back swing center point P as a fulcrum. Therefore, the position and posture of the seat part 2 are balanced in a state in which the load applied by the user A to the seat part 2 (translational force in balance with the lifting force acting on the user A from the seat part 2 ) (more specifically, the center of gravity of the load distributed on the contact surface between the user A and the seat part 2) is located directly below the center point P of the front and rear swing, that is, the line of action of the load passes through P , The state of the straight line in the up and down direction. And, when the point of action of the load acting on the seat part 2 from the user A is displaced due to the inclination of the upper body of the user A, the position and posture of the seat part 2 are automatically restored to the above-mentioned balanced state. Therefore, viewed from the sagittal plane, the line of action of the load that user A acts on the seat portion 2 and the line of action of the supporting force (translational force) transmitted from the third joint 14 of each leg support 3 to the calf support 13 generally pass through the common Point P. As a result, it is possible to prevent these lines of action from being separated in the front-rear direction and to cause the load and support force to act as a couple on the seating portion 2 . Therefore, the position of the seat part 2 can be prevented from shifting relative to the user, and the position and posture of the seat part 2 can be stabilized. Furthermore, a desired lifting force can be stably and appropriately acted on the user A from the seat part 2 . the

In addition, the total target lifting force is allocated to the left and right leg supports 3L, 3R corresponding to the ratio of the pedaling force of the user A's right leg to the pedaling force of the left leg, and the total lifting force borne by each leg support 3 is determined, and the total lifting force The amount of force bearing is generated at 3 places of each leg support. Therefore, especially in the state where the lift control ON·OFF switch 54 is operated to ON, the lift force (target lift force) set by the key switch 53 can be smoothly and stably moved from the seating portion 2 acts on user A, and effectively reduces the burden on each leg of user A. the

Supplementary description of the following content: as mentioned above, the total target lifting force is the lifting force setting value (target lifting force) of the key switch 53 plus the force of the size of the supporting force for supporting the following weight (more More precisely, it is the value obtained by passing the added value through a low-pass filter), wherein the weight is the weight obtained by subtracting the total weight of the lower part of each supporting force sensor 30 from the overall weight of the walking assist device 1 (or the overall weight of the walking assist device 1). Therefore, as described above, by determining the total amount of lifting force borne by each leg rest 3, as a result, the target value of the lifting force that should act on the user A from the seat portion 2 corresponds to the target lifting force of the user A. The ratio of the pedaling force of the right leg to the pedaling force of the left leg is distributed to the left and right leg mounts 3L, 3R. Then, the motors 27L and 27R of the respective leg rests 3L and 3R are controlled so that the borne amount of each leg rest 3L and 3R of the distributed target lifting force acts on the seating part 2 . the

And, since the spring restoring force is generated at each leg frame 3, the more the user A's knee is bent, the greater the lifting force obtained from the walking assisting device 1 is. This makes it easier for the user A to truly feel the assistance of the walking assistance device 1 . At the same time, by appropriately setting the value of the spring constant k of the spring restoring force (refer to the above formula (6)) in advance, it is possible to prevent the posture of each leg frame 3 from deviating from an inappropriate posture. the

At the same time, when the lifting control ON/OFF switch 54 is operated to the OFF state, a value corresponding to the weight of the part above the supporting force sensor 30 of the walking assisting device 1 is determined and used as the total target lifting force. In this state, as long as the user does not put his body weight on the seat part 2 intentionally, the seat part 2 will always be in contact with the user A, and the balance will be maintained in a state where no force is generated between the two. And in this state, when the lifting control ON/OFF switch is operated to ON, the lifting force that changes rapidly can be prevented from acting on the user from the seat portion 2 by the low-pass filter (refer to S303 in FIG. 10 ). In the phenomenon of A, the lifting force can be smoothly applied to the user A. the

In addition, since the PD control rule (feedback control rule) and the feedforward control rule are determined and used to determine the current instruction value of each motor 27, the lifting force can be controlled stably at high speed. the

In addition, although the spring return force is added to the target value (control target value) of the total lifting force bearing amount of each leg frame 3 in the above-described embodiment, it is also possible to omit adding the spring return force (specifically, omitting FIG. 10 ). S305, S307, S310, S312 processing in). At this time, it is only necessary to input the Fankle_t obtained in S301 in FIG. 10 into S302. the

In addition, the guide rail 22 shown in FIG. 1 is not necessarily an arc-shaped member, and may also be a part (elliptical arc) in an ellipse, as long as the thigh rest 11 can swing in the front-back direction, other shapes. When the guide rail 22 is not arc-shaped, the position of the center point P of the front-back swing varies within a predetermined range according to the movement of the walking assistance device 1 . At this time, when calculating the Fankle value, the rotation center of the thigh frame 11 at that moment is determined every predetermined calculation processing cycle, and this is taken as the swing center point P in the front-back direction. In addition, the straight line connecting the central point P and the third joint 14 is used as the line of action of Fankle, and the Fankle only needs to be calculated in the same way as in the above-mentioned embodiment. the

Furthermore, when a device member (belt, etc.) for preventing meaningless rotation of the seat part 2 is attached to the walking assisting device 1, the front-back swing center point P may be set at a position other than the width of the seat part 2 in the front-rear direction. the

Next, a second embodiment of the present invention will be described with reference to FIGS. 14 and 15 . In addition, the mechanical configuration of the walking assistance device in this embodiment is the same as that of the first embodiment, and only a part of the control processing is different from that of the first embodiment. Therefore, in the description of the present embodiment, the same reference numerals are used for the same components or the same functions as those of the first embodiment, and description thereof will be omitted. Meanwhile, this embodiment mode is an embodiment mode of the first invention to the fourth invention and the sixth invention among the first embodiment and the present invention. the

FIG. 14 is a block diagram showing a functional mechanism of the arithmetic processing unit 51 of the control unit 50 in this embodiment. As shown in the figure, in this embodiment, instead of the lifting force setting key switch 53, an assist ratio setting key switch 70 (which corresponds to the target assist ratio in the present invention) for setting the following target assist ratio is provided. assist ratio setting mechanism), the target assist ratio is the total pedaling force of the user A (the sum of the pedaling force of the left leg and the pedaling force of the right side), the force assisted by the walking assistance device 1 relative to the total pedaling force The target value of the proportion. In addition, the assist ratio setting key switch 70 is constituted by a digital switch or a plurality of selector switches so that it can directly set a desired assist ratio target value or select from a variety of target values prepared in advance. Set it up. the

Further, the operation signal of the assist ratio setting key switch 70 (the target assist ratio setting value indicated by the operation signal) can be input to the left and right target commitment determining means 71 of the arithmetic processing unit 51 . Here, among the functional mechanisms of the arithmetic processing unit 51 in this embodiment, only the left and right target commitment determination unit 71 is different from the first embodiment, and the arithmetic processing unit 51 other than the left and right target commitment determination unit 71 The processing of each functional mechanism is the same as that of the first embodiment. Therefore, the following description of this embodiment will focus on the processing of the left and right target commitment determination means 71 . the

In the present embodiment, the measurement values of the measurement processing mechanisms 60R, 60L, 61R, 61L, 62R, and 62L, the operation signals of the assist ratio setting key switch 70, and the lift control ON/OFF switch 54 are controlled. It is input in the left and right target burden determining mechanism 71, and the left and right target burden determining mechanism 71 determines the control target value of each leg frame 3 according to these input values (transmitted from the third joint 14 of each leg frame 3 to The supporting force target value of the calf frame 13, or the target value of the supporting force sensor 30 acting on the leg frame 3) is processed. the

As will be described below, the left and right target burden determination means 71 determines the control target value of each leg link 3 in each control processing cycle of the arithmetic processing device 51 . FIG. 15 is a block diagram showing the flow of this process. the

First, at S1301, the measured value Fankle_R of the total lifting force bearing amount of the right leg frame 3R and the measured value Fankle_L of the total lifting force bearing amount of the left leg frame 3L obtained by each supporting force measurement processing mechanism 62 are Add up. From this the total lifting force Fankle_t is calculated. the

Next, at S1302, the value obtained by subtracting the auxiliary weight supporting force described later from the total lifting force Fankle_t and the pedaling force measurement values FRF_R and FRF_L of each leg obtained by the pedaling force measurement processing mechanism 60 are calculated. The total, that is, the measured value (FRF_R+FRF_L) of the full pedaling force is used to calculate the actual assist ratio, which is the ratio of the force actually assisted by the walking assist device 1 to the full pedaling force in the full pedaling force. Specifically, the required support force for supporting the following weight (the support force balanced with the gravity corresponding to the weight), or the required support force for supporting the entire weight of the walking assistance device 1 (the support force equivalent to The supporting force balanced with the gravity of the overall weight) is used as the weight supporting force of the auxiliary device, and the size of the supporting force of the auxiliary device is recorded in advance and stored in a storage not shown in the figure, wherein the weight refers to from The overall weight of the walking assistance device 1 is the weight obtained by subtracting the sum of the weights of the supporting force sensors 30 and below. Then, the value obtained by subtracting the weight supporting force of the assisting device from the total lifting force Fankle_t (this refers to the upward lifting force acting on the user A from the seat part 2 at this time) is divided by the full pedaling force The measured value of (FRF_R+FRF_L). From this, the actual assist ratio is obtained. That is, the actual assist ratio is obtained by the formula of actual assist ratio=(Fankle_t−assist device weight supporting force)/(FRF_R+FRF_L). the

Then, at S1303, according to the operation signal of the lift control ON/OFF switch 54 (whether the switch 54 shows ON or OFF), the actual assist ratio and the assist ratio set by the assist ratio are selectively output. One of the set values of the target assist ratio set by the key switch 70 . Specifically, when the control ON/OFF switch 54 is lifted to indicate OFF, the actual assist ratio obtained in S1302 is selected and output. Simultaneously, when lifting control ON/OFF switch 54 and showing ON, then select the setting value of described target auxiliary ratio and output. the

Next, the output value of S1303 is passed through a low-pass filter in S1304, thereby determining an actually used target assist ratio which is an actually used target assist ratio. The low-pass filter in S1304 is used to prevent the output value of S1303 from drastically changing (when the set value of the target assist ratio is changed, or when the output of S1303 is changed from the actual assist ratio to the target assist ratio, etc.) In practice, a device that assists in making a drastic change in the goal and avoids a drastic change in the lifting force acting on the user A from the seating part 2 is used. The cutoff frequency of this low-pass filter is, for example, 0.5 Hz. the

Thereafter, at S1305, the actual use target assist ratio is multiplied by the measured value FRF_R of the pedaling force of the user A's right leg obtained by the right pedaling force measurement processing unit 60R. In this way, the right target lifting commitment amount of the lifting force acting on the user A from the seat part 2 is determined, wherein the right target lifting commitment amount is a target value of the bearing amount of the right leg support 3R. Similarly, at S1306 , the actual use target assist ratio is multiplied by the measured value FRF_L of the pedaling force of the user A's left leg obtained by the left pedaling force measurement processing unit 60R. In this way, the left target lifting commitment amount of the lifting force acting on the user A from the seat part 2 is determined, wherein the left target lifting commitment amount is a target value of the bearing amount of the left leg support 3L. the

In addition, the processing of S1301 to S1306 corresponds to the target lifting commitment amount determining means in the above-mentioned fifth and sixth inventions. the

Next, at S1307, the following ratio is determined according to the measured value FRF_R of the pedaling force of the right leg and the measured value FRF_L of the pedaling force of the left leg obtained by each of the pedaling force measurement processing units 60. The ratio refers to a ratio for distributing the weight supporting force of the auxiliary device to the left and right leg supports 3 . The processing of this S1307 is the same as the processing of S304 in FIG. 10 in the first embodiment. the

Then, at S1308, the right side ratio obtained at S1307 is multiplied by the auxiliary device weight supporting force. From this, the right target device supporting force bearing amount of the assisting device weight supporting force is obtained, wherein the right target device supporting force bearing amount is a target value of the bearing amount of the right leg link 3R. Likewise, at S1311, the left side ratio obtained at S1307 is multiplied by the auxiliary device weight supporting force. From this, the left target device supporting force bearing amount in the assisting device weight supporting force is obtained, wherein the left target device supporting force bearing amount is a target value of the bearing amount of the left leg link 3L. In addition, the processing of S1307, S1308, and S1311 may be set to be performed in parallel with the processing of S1301 to S1306. the

Subsequently, the processing of S1309, S1310 of the right leg frame 3R and the processing of S1312, S1313 of the left leg frame 3L are performed. In the processing of S1309 and S1310 of the right leg support 3R, first, in S1309, the right target lifting commitment amount obtained in the above S1305 and the right target device support force bearing amount obtained in the above S1308 are added. In this way, a provisional control target value Tp_Fankle_R, which is a provisional value of the control target value of the right leg link 3R, is determined. Then, by passing the provisional target value Tp_Fankle_R through the low-pass filter in S1310, the control target value T_Fankle_R of the right leg link 3R is finally obtained. The low-pass filter in S1309 is a means for removing noise components accompanying the variation of the knee angle θ1. The cutoff frequency is, for example, 15 Hz. the

Similarly, in the processing of S1312 and S1313 of the left leg support 3L, first, in S1312, the left target lifting commitment amount obtained in S1306 and the left target device supporting force commitment amount obtained in S1311 are added. Accordingly, a provisional control target value Tp_Fankle_L, which is a provisional value of the control target value of the left leg link 3L, is determined. Then, by passing the provisional target value Tp_Fankle_L through the low-pass filter in S1313, the control target value T_Fankle_L of the left leg link 3L is finally obtained. the

The control target value of each leg support 3 determined as described above refers to the sum of the weight supporting force of the auxiliary device and the entire lifting force acting on the user A from the seat part 2 (that is, the total lifting force), The target value of the supporting amount of each leg frame 3 . the

The above is the processing of the left and right target commitment determination means 71 in this embodiment. Supplement the following content: the processing of calculating the left and right target lifting loads in S1305 and S1306 is equivalent to the method of distributing the following values to the left and right leg supports 3 from the right side ratio and the left side ratio. The sum of the measured values FRF_R, FRF_L of the pedaling force of the left and right legs of the user A is multiplied by the value of the actual use target assist ratio (corresponding to the target value of the overall lifting force acting on the user A from the seat portion 2). the

In addition, the processes of S1307, S1308, and S1311 correspond to the allocation means in the fifth invention and the sixth invention. In addition, the processes of S1309, S1310, S1312, and S1313 correspond to the control target force target value determination means in the sixth invention. the

In the second embodiment described above, the line of action of the support force (translational force) transmitted from the third joint 14 of each leg support 3 to the calf support 13 is from the center point of the third joint 14 and passes through The straight line of the front-back swing center point P, wherein the front-back swing center point P exists above the seat part 2 within the front-back direction width of the contact surface between the seat part 2 and the user A. And, each leg support 13 can swing freely in the front-back direction with respect to the seat portion 2 with the front-back swing center point P as a fulcrum. Therefore, similar to the first embodiment, it is possible to prevent the seat part 2 from being displaced relative to the user A, and to stabilize the position and posture of the seat part 2 . Furthermore, a desired lifting force can be stably and appropriately acted on the user A from the seat portion 2 . the

In addition, while assigning the target value of the full lifting force that should act on the user A from the seat part 2 to the left and right leg supports 3L, 3R in accordance with the ratio of the pedaling force of the user A's right leg and the pedaling force of the left leg, corresponding The ratio of the pedaling force of the right leg of the user A to the pedaling force of the left leg distributes the assisting device weight supporting force for supporting the entire weight of the walking assisting device 1 to the left and right leg supports 3L, 3R. In this way, a control target value is determined as a target value of the total lifting force bearing amount of each leg frame 3 , and the supporting force of the control target value is generated in the leg frame 3 . Therefore, especially when the lift-up force control ON/OFF switch 54 is operated to be ON, the lift-up force corresponding to the assist ratio set by the key switch 70 can be smoothly and stably released from the seat portion 2 . It acts on user A and can effectively reduce the burden on user A's legs. the

In addition, when the lift control ON/OFF switch 54 is operated to the OFF state, the actual assist ratio is determined as the actual use target assist ratio. Therefore, in this state, as long as the user A does not intentionally put his body weight on the seat part 2, the seat part 2 can always contact the user A and maintain a balance in a state where no force is generated between the two. And, because of this state, when the lifting control ON/OFF switch 54 is operated to ON, it is possible to avoid the sudden change of the lifting force caused by the above-mentioned low-pass filter (refer to S1304 in FIG. 15 ) from the seat portion 2. The phenomenon acting on the user A enables the lifting force to act on the user A smoothly. the

In addition, since the current instruction value of each motor 27 is determined by using the PD control rule (feedback control rule) and the feedforward control rule together, the lifting force can be controlled stably at high speed as in the first embodiment. the

In addition, in the second embodiment, adding the spring restoring force described in the above-mentioned first embodiment to each control target value T_Fankle_L, T_Fankle_R is omitted. However, like the first embodiment, the spring restoring force of each leg link 3 may be determined and added to each control target value T_Fankle_L, T_Fankle_R. the

Furthermore, in the above-described first and second embodiments, even when the lift control ON/OFF switch 54 is in the OFF state, the operation control of the motors 27R and 27L can be performed. However, when the switch 54 is in the OFF state, for example, the output to the drive circuit may be stopped and the power supply to the motors 27 may be stopped while performing the calculation processing of the calculation processing device 51. In this manner, a lifting force corresponding to the slight force (or zero) exerted by the user A on the seating part 2 is generated at the moment when the lifting control ON/OFF switch 54 is turned ON. And thereafter, until the final total lifting force is brought into play, by means of the effect of the low-pass filter (refer to S303 in Fig. 1 ), while reducing the impact on the user A, the lifting from the lifting position can be realized very smoothly. The transition from force generation to a state of gradual increase. Furthermore, it is possible to reduce the power consumption of each motor 27 when the switch 54 is in the OFF state. the

In addition, in the above-described first and second embodiments, although the receiving portion is constituted by the saddle-shaped seating portion 2, the receiving portion may be constituted by, for example, a flexible member. An embodiment in this case will be described below, and it will be regarded as a third embodiment. In this third embodiment, for example, as shown in FIG. The two belt-shaped flexible members 101L and 101R of the receiving portion. One end of each flexible member 101R, 101L is fixed to the belt 100 on the front side of the user A, and the other end is fixed to the belt 100 on the back side of the user A. In addition, the flexible member 101R passes through the inside of the user A's right leg and contacts the crotch of the user A, and the flexible member 101L passes through the inside of the user A's left leg and contacts the user A's crotch. Thus, the crotch portions of the flexible members 101R and 101L function as receiving portions that receive part of the weight of the user A from above. At the same time, the thigh frame 11 of each leg frame 3 is extended through the first joint 102 provided on the left and right sides of the waist belt 100 to at least be able to swing in the front and rear direction (swing with the first joint 102 as a fulcrum). At this time, the swing center point (predetermined point in the present invention) is located above the receiving portions of the flexible members 101R, L when viewed from the sagittal plane. The configuration of the portion below the thigh frame 11 of each leg frame 3 may be the same as that in the first embodiment and the second embodiment. In addition, an actuator for driving the second joint can be mounted on this second joint, for example. the

Meanwhile, in the first embodiment and the second embodiment, although the graph of FIG. 7 is used at each pedaling force measurement processing mechanism 60, it is also possible to step on each leg using, for example, a graph as shown in FIG. 17 . The temporary measured value FRF_p of the force is converted into the measured value FRF. An embodiment in this case will be described below, and this will be referred to as a fourth embodiment. The graph of FIG. 17 in this fourth embodiment is set so that FRF becomes a negative value when the provisional measurement value FRF_p is smaller than the threshold value FRF1. In more detail, in the chart of Figure 17, when FRF_p is a value between the threshold FRF1 and the threshold FRF3 slightly smaller than the threshold (FRF3>0 in this example), FRF decreases with the decrease of FRF_p However, it decreases linearly, and when FRF_p is smaller than the threshold FRF3 (including the case of FRF_p<0), FRF maintains a negative constant (FRF value when FRF_p=FRF3). the

Here, when the user A walks, for example, when raising the right leg, the output values of the MP sensor 38R and the heel sensor 39R become very small values (values close to 0) or is a negative value, the temporary measured value FRF_p_R is smaller than the threshold FRF1. At this time, the measured value FRF_R of the pedaling force of the right leg obtained using the graph of FIG. 17 is a negative value. the

In addition, when the negative measured value FRF_R is obtained using the graph in FIG. 17 in this way, in the first embodiment, a part of the processing in FIG. Change. That is, at S304 in FIG. 10 , when a negative measurement value FRF_R is obtained, the ratio of the two ratios is set to a predetermined ratio determined in advance. For example, as described above, when FRF_R<0, the ratio of left side:right side=1.1:−0.1 is set. That is, corresponding to the FRF with a negative value among the left and right blending ratios, the blending ratio is set to a negative predetermined value (-0.1 in this embodiment), and the other blending ratio is set to A positive predetermined value (1.1 in this embodiment). In addition, it is most preferable to set the sum of the left side blending ratio and the right side blending ratio to 1 for these predetermined values. And the processing of S306 and S311 is performed using the matching ratio. At this time, for example, when the output target total lifting force of S303 in FIG. 10 is 200N, the outputs of S306 and S311 are respectively -20N and 220N. In addition, the leg whose temporary measured value FRF_p is smaller than the threshold value FRF1 (in the above example, the right leg) is judged as a free leg, and is set to not perform spring recovery force in S305 or S310 corresponding to the free leg. The calculation process of (set the spring return force corresponding to the free leg to 0). Thus, at the beginning of the single-leg support stage (the stage when only one leg is the standing leg), the second joint 12 of the leg support 3 on the free leg side is driven to the bending side, which can assist the user A's free movement. Leg lifts on the side of the leg. the

Also in the second embodiment, part of the processing in FIG. 15 (processing by the left and right target commitment amount determination means 71 ) is modified as follows, for example. That is, at S1307 in FIG. 15 , when a negative value measurement value FRF_R is obtained, as described in the first embodiment, corresponding to the FRF with a negative value in the left side ratio and the right side ratio, it is The ratio is set to a negative predetermined value (for example, -0.1), and the other ratio is set to a positive predetermined value (for example, 1.1) (most preferably left ratio+right ratio=1) . And the processing of S1308 and S1311 is carried out using the matching ratio. Thus, as in the case described in the first embodiment, at the beginning of the single-leg support phase (the phase when only one leg is the standing leg), the first position of the leg support 3 on the free leg side The two joints 12 are driven toward the bending side, and can assist the user A in raising the free leg side. the

In addition, in each of the above-mentioned embodiments, the first force sensor is constituted by the MP sensor 38 and the heel sensor 39, and these sensors 38, 39 are provided on the foot mounting part 15 as shown in FIG. A is between the underside of the foot of the standing leg and the ground. However, the installation position of the first force sensor is not limited to this. For example, as shown in FIG. 18 , the first force sensor may be provided on the foot attachment portion. An embodiment of this case will be described below, and this will be referred to as a fifth embodiment. the

As shown in FIG. 18 , in the fifth embodiment, a foot support member 100 is provided inside the ring member 36 of the foot attachment portion 15 . The foot supporting member 100 is in the shape of a slipper, and is composed of a plate-shaped sole member 101 (a cushion-shaped member in the shoe) that is in contact with the bottom surface of the user A's foot almost entirely, and is connected to the sole member 101. The arched member 102 (a member whose cross section is roughly semicircular) is formed. The lower ends of both ends of the arch member 102 are integrated with the two sides of the sole member 101 . The front end portion of the user A's foot can be inserted into the arch member 102 . And the foot is supported on the sole member 101 in the inserted state. The sole member 101 and the arch member 102 can be made of a material having predetermined rigidity, such as metal or resin, for example. the

In addition, a tension sensor 103 constituting a first force sensor is installed between the upper outer surface of the arch member 102 and the upper inner surface of the ring member 36 . The tension sensor 103 is engaged with the arched member 102 and the annular member 36 . The tension sensor 103 may be, for example, a tension type load cell. At this time, the foot support member 100 is provided inside the ring member 36 in a non-contact state with the ring member 36 and the shoe body 35 . Thus, the foot support member 100 is suspended from the ring member 36 via the tension sensor 103 so that the force supporting the foot support member 100 from below is not acted upon by the ring member 36 and the shoe body 35 . the

In addition, cushioning materials for protecting the feet of the user A may be provided on the upper surface of the sole member 101 and the inner surface of the arch member 102 . the

The above is the structure of the leg attachment part 15 in this embodiment. In addition, the MP sensor 38, the heel sensor 39, and the inner pad member 37 are not included in the foot mounting part 15 in this embodiment. And, when installing the foot mounting part 15 of this embodiment on each foot of the user A, it is only necessary to pass the toe front end of the foot through the arch member 102 of the foot support member 100, and the foot The part is carried on the sole member 101, and the foot is inserted into the inside of the shoe body 35 from the shoe body opening of the shoe body 35. the

When using the walking assistance device in this embodiment having the foot mounting portion 15 configured as described above, the tension sensor 103 is used to measure the pedaling force of the standing leg of the user A. During the measurement, the standing leg The pedaling force is measured as the tension acting on the tension sensor 103. the

In addition, in this embodiment, the output of the tension sensor 103 of each left and right foot mounting part 15 is input into each pedaling force measurement processing mechanism 60 of the arithmetic processing device 51 instead of the output of the MP sensor 38 and the heel sensor 39. . And, each stepping force measurement processing mechanism 60 obtains the following numerical value, and takes it as the temporary measurement value FRF_p of each leg of the user A, said numerical value refers to the force measurement value represented by the output of the tension sensor 103 (assuming that the tension force is positive value) after passing through the low-pass filter, wherein the tension sensor 103 corresponds to each pedaling force measurement and processing mechanism 60 . Then, each pedaling force measurement processing means 60 obtains the measured value FRF of the pedaling force according to the above-mentioned graph of FIG. 7 (or the graph of FIG. 17 ) based on the provisional measured value FRF_p. the

Other than the configuration and processing described above, it is the same as the above-mentioned first embodiment (or second embodiment). the

Industrial Usability

As noted above, the present invention finds utility as a device that properly assists a user in walking. the

Claims (6)

1. A walking assist device comprising: a receiving portion disposed between the bases of the user's legs to bear part of the user's weight from above; a pair of left and right thigh frames, which are respectively connected to the receiving part via respective first joints arranged below the receiving part; A pair of left and right calf frames are respectively connected to each leg frame via their corresponding second joints; A pair of left and right foot mounting parts, which are respectively connected to each lower leg frame through their corresponding third joints, and are respectively installed on the feet of the left and right legs of the user, and are mounted on each of the user's legs. The leg is grounded when it becomes the standing leg; The driver for the left side drives the second joint of the left leg support, which is composed of the first joint, the thigh support, the second joint, the lower leg support, the third joint and the foot mounting part on the left side. constitute; The right side uses the driver, which drives the second joint of the right leg support, and the right leg support is composed of the first joint, the thigh support, the second joint, the calf support, the third joint and the foot mounting part on the right side constitute, In addition, the walking assistance device drives the second joint of each leg frame by the driver, thereby causing an upward lifting force to act on the user from the receiving part, and is characterized in that: Each leg support is connected to the receiving part in such a manner that when the user's sagittal plane is used to observe the leg support, the leg corresponding to the leg when each leg of the user becomes a standing leg The line of action of the support force of the third joint of the bracket acting on the calf frame passes through the swing center point from the third joint, and the swing center point is located within the width of the front-back direction of the contact surface between the receiving part and the user. the position above the receiving portion, This walking assisting device further includes a mechanism that uses the supporting force as a control target force, and controls the actuators so that the control target force becomes a predetermined target value for each leg frame, thereby making the lifter exert force on the user. 2. The walking assistance device according to claim 1, wherein: The first joint of each leg frame connects the thigh frame of the leg frame and the receiving portion in such a manner that the leg frame can swing freely at least in the front-rear direction with the swing center point as the swing center. 3. The walking assistance device according to claim 1, wherein: The first joint of each leg frame is to connect the thigh frame of the leg frame and the receiving part so that the leg frame can swing freely in the front-rear direction and the left-right direction, and at least the front-to-back direction swing of the leg frame It is configured such that the center point is located above the receiving portion. 4. The walking assistance device according to claim 1, wherein: The driver for the left side and the driver for the right side are connected to the thigh frame at positions closer to the receiving portion than the second joint of the left leg frame and the second joint of the right leg frame, respectively. It is provided and equipped with a pair of left and right power transmission mechanisms that transmit the driving force of each driver to the second joint. 5. The walking assistance device according to claim 1, wherein: The walking assist device has: a pedaling force measuring mechanism for measuring the pedaling force of each leg of the user based on a force detection value displayed by an output of a first force sensor provided on each foot mounting portion; a target lifting force setting mechanism that sets a target lifting force that is a target value of an upward lifting force acting on the user from the receiving portion; The second force sensor is installed between the lower end of the calf frame of each leg frame and the third joint, or between the third joint of each leg frame and the foot mounting part; A control object force measurement mechanism, which measures the support force actually acting on the calf frame from the third joint of each leg support as the control object force according to the force detection value displayed by the output of the second force sensor; a total target lifting force determination mechanism that determines the total target lifting force as the sum of the target lifting force and the supporting force that is to be subtracted from the overall weight of the walking assistance device. The differential weight of the total weight of the lower part of each second force sensor in the walking assisting device is supported on the floor, or the supporting force for supporting the entire weight of the walking assisting device on the floor; distribution mechanism, which distributes the total target lifting force to each leg support according to the ratio of the pedaling force of the user's left leg to the pedaling force of the right leg, thereby determining the total target lifting force a target load as a target value of the load of the left leg brace and a target load as a target value of the target load of the right leg brace; A driver control mechanism that makes the difference between the controlled force of the left leg frame and the target load close to zero based on the control target force of the left leg frame and the target load of the left leg frame to control the driver for the left side, and according to the control object force of the right leg frame and the target load of the right leg frame, the difference between the control object force of the right leg frame and the target load close to 0 to control the right side with the driver. 6. The walking assistance device according to claim 1, wherein: The walking assist device has: a pedaling force measuring mechanism for measuring the pedaling force of each leg of the user based on a force detection value displayed by an output of a first force sensor provided on each foot mounting portion; The second force sensor is installed between the lower end of the calf frame of each leg frame and the third joint, or between the third joint of each leg frame and the foot mounting part; A control object force measurement mechanism, which measures the support force actually acting on the calf frame from the third joint of each leg support as the control object force according to the force detection value displayed by the output of the second force sensor; a target assist ratio setting mechanism that sets a target assist ratio that is a target value of a ratio of a total pedaling force assisted by the walking assist device to the total pedaling force, wherein the total pedaling force is means the sum of the pedaling force of each leg of the user in question; a target lifting load determining means for determining left and right of the upward lifting force to be applied to the user from the receiving part by multiplying the target assist ratio by the stepping force of each leg of the user; The target lifting capacity of the side leg support, wherein, the target lifting capacity of the left leg support is the target value of the left leg support, and the target lifting capacity of the right leg support is the right The target value of the bearing capacity of the side leg support; A distributing mechanism for distributing the supporting force to each of the leg frames according to the ratio of the pedaling force of the user's left leg to the pedaling force of the right leg, whereby the bearing force of the left leg frame in the supporting force is and the bearing amount of the right leg frame are respectively determined as the target device supporting force bearing amount of each leg frame. The difference weight of the total weight of the lower portion of the second force sensor is a support force for supporting the floor, or a support force for supporting the entire weight of the walking assist device on the floor; A control object force target value determining mechanism that determines the sum of the target lifting commitment amount of the left leg frame and the target device support force load amount as the target value of the control object force of the left leg frame, and The sum of the target lifting commitment of the right leg support and the target device support force commitment is determined as the target value of the control object force of the right leg support; A driver control mechanism, which makes the difference between the control object force of the left leg frame and the target value close to zero according to the control object force of the left leg frame and the target value of the control object force of the left leg frame The drive for the left side is controlled in a manner, and, according to the control object force of the right leg frame and the target value of the control object force of the right leg frame, the control object force of the right leg frame The driver for the right side is controlled so that the difference from the target value becomes close to 0.

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