JP6537855B2 - Articulation assistance device - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an articulatory movement assisting apparatus capable of supporting the user's muscular strength without excessively restraining the motion of a user who wears it, during periodic repetitive movements of joints such as the user's walking. .

  Conventionally, a wearable auxiliary device has been proposed to support movements such as walking of a physically disabled person who has lost muscle strength or an elderly person who has lost strength, and the present applicant is also a prior application. In the 2013-208397 gazette (patent documents 1) and Unexamined-Japanese-Patent No. 2014-18536 (patent documents 2), the auxiliary device of joint movement is proposed. In such a joint movement assisting device, a flexible assisting force transmitting portion is used, and both end portions thereof are attached to both sides of the user's joint at predetermined timing according to the joint angle of the user. It is possible to apply an assisting force in the tension direction to the assisting force transmitting portion. Therefore, by using such an articulation assist device, it is possible to perform muscle power assistance such as lifting the free leg during walking and swinging forward.

  By the way, in the joint movement assist device, generally, an approximately constant assist force is applied over a predetermined time at a predetermined timing during the movement of a joint, for example, as shown in FIG. It is done.

  However, since the speed and purpose of exercise for each user are variously different, in order to respond to such exercise for each user and the purpose thereof, conventional joint exercise that applies a certain assist force It was hard to say that the auxiliary equipment was sufficient. In order to cope with such motion speed and purpose for each user, it is also conceivable to improve the operation control accuracy by using a large number of sensors and calculation means for performing complicated calculations. However, if the structure and control of the auxiliary device are complicated by using a large number of sensors and advanced calculation means, the joint motion auxiliary device becomes larger and the weight increases and the control is delayed, resulting in a simple structure. It is desirable to apply an assist force suitable for the target joint movement by means of the control method and the auxiliary device of the control method.

JP, 2013-208397, A JP, 2014-18536, A

  The present invention has been made in the background of the above-mentioned circumstances, and the problem to be solved is an articulatory movement assisting device having a novel structure capable of giving an appropriate assisting force to a user by a simple structure and control. To provide.

  As a result of the inventors of the present invention carrying out further studies and experiments based on this subject, when the assist force is changed with the passage of time (progression of joint movement), the assist is performed according to the change of the assist force. We found that the effects of force on joint movement differed. Based on such findings, the present inventors have completed the joint motion assisting apparatus according to the present invention in which the assist force for joint motion can be appropriately set by a simple structure and control.

  The following describes aspects of the present invention made to solve such problems. In addition, the component employ | adopted in each aspect described below can be employ | adopted as much as possible in arbitrary combination.

That is, according to the first aspect of the present invention, there is provided an auxiliary power transmission unit having flexibility, and the first power transmission unit provided at one end of the auxiliary power transmission unit and mounted on one part sandwiching a user's joint. A second attachment portion provided at the other end of the auxiliary force transmission portion and attached to the other portion of the user sandwiching the joint, and the auxiliary force transmission portion Driving means for applying an assist force in the tension direction, a joint angle sensor for detecting the bending angle of the joint of the user, and assist timing for determining the operation timing of the driving means based on the detection value of the joint angle sensor In the joint movement assisting device having a control means, an output characteristic setting means for setting a target value of the assist force by the drive means is provided, and the target value of the assist force set by the output characteristic setting means is Within the period of periodic motion While being set with chevron profile that varies with the passage of the operating time of the drive means Te, the output characteristic setting means the peak position where the target value of the assisting force is maximized, and one step of a unit gait It is characterized in that it comprises peak position setting means which can be changed and set in the back and forth direction of the elapsed time within one cycle of the periodic motion in the cycle.

In the first aspect of the joint movement assisting apparatus constructed according to the present invention, the target value of the assist force of the drive means is set with a chevron profile by the output characteristic setting means, and the assist force of the drive means is set during operation. The size changes with time. Therefore, an appropriate assist force can be efficiently applied to the user in response to a change in the necessary assist force as the joint movement progresses.

  Furthermore, for example, when using the joint motion assist device for assisting in the walking motion, if the peak position of the assist force is set to the first half of the joint motion, the cycle (stepping pace) of the walking motion can be shortened by the action of the assist force. On the other hand, if the peak position of the assist force is set in the latter half of the joint movement, the stride can be increased by the action of the assist force. Thus, based on the new finding that the influence of the assist force on the cycle of the joint movement can be controlled to some extent by appropriately setting the peak position of the assist force, the peak position of the assist force is determined by the peak position setting means. Changeable setting possible. As a result, an assist force can be obtained according to the desired form of joint movement, and joint movement can be assisted more highly.

  A second aspect of the present invention is the articulatory assistance device according to the first aspect, wherein the assist timing control means determines a period of the joint motion of the user by the joint angle sensor. The assist timing control means sets the operation time of the drive means based on the cycle of the joint motion, while measuring based on the time interval when the detected value of the flexion angle of the joint becomes maximum.

  According to the second aspect, the assist timing control means determines the period of the joint movement based on the interval at which the detected value of the bending angle of the joint by the joint angle sensor is maximum, thereby achieving the periodicity of the joint movement. It is possible to accurately measure the period of joint movement with high accuracy. Furthermore, the period of action of the assist force by the operation of the drive means is set based on the cycle of the joint movement specified by the assist timing control means, whereby a specific one requiring an assist force during one cycle of joint movement is provided. The target assist force can be efficiently applied during the period.

A third aspect of the present invention is the articulatory assistance device according to the first or second aspect, wherein the output characteristic setting means sets a maximum value of the target value of the assist force at the peak position. An output setting means is provided.

  According to the third aspect, in addition to applying the assist force with the output characteristic according to the target joint movement mode, the level of the applied assist force is adjusted as needed by the maximum output setting means. Can. Therefore, the assist force can be appropriately adjusted and exerted according to the user's muscular strength and preference, the desired form of joint movement, and the like.

A fourth aspect of the present invention is the articulation assistance device according to any one of the first to third aspects, wherein the target value of the assist force is the operating time of the drive means by the output characteristic setting means. It is made to be changed gradually with progress.

According to the fourth aspect, by controlling the target value of the assist force to be gradually changed by the output characteristic setting means, the durability of the drive means and the transmission path of the assist force by rapidly changing the output can be increased. While a fall etc. are avoided, a user's load, sense of incongruence, etc. accompanying sudden change of assistant power may be canceled.

  According to a fifth aspect of the present invention, in the articulation assist apparatus described in any one of the first to fourth aspects, a target of the assist force F when time t has elapsed from the start of operation of the drive means. Function f (α of the set value A set by the maximum output setting means for setting the maximum value of the target value of the assist force and the setting value α set by the peak position setting means and the elapsed time t , T) satisfy F = A · f (α, t).

  According to the fifth aspect, while the maximum level of the assist force by the drive means is adjusted by the set value A set by the maximum output setting means, the peak timing at which the assist force becomes maximum is determined by the peak position setting means It is determined by the function f (α, t) of the set value α to be set and the elapsed time t. Therefore, by setting the setting values A and α separately, it is possible to set the magnitude of the assist force and the output characteristic (peak position) of the assist force.

  According to a sixth aspect of the present invention, in the articulatory assist device described in the fifth aspect, the function f (α, t) is a sine function.

  According to the sixth aspect, by setting the function f (α, t) as a sine function, the maximum level of the assist force can be easily set by the set value A, and the peak position of the assist force can be obtained. It can be easily set by the set value α, and the maximum levels and peak positions of the assist forces can be set easily and accurately.

  According to a seventh aspect of the present invention, in the articulation assistance device according to any one of the first to sixth aspects, a load sensor for detecting a load in a tensile direction acting on the assisting force transmitting portion is provided. The operation of the driving means is feedback-controlled based on the detected value of the load sensor such that the load acting on the auxiliary force transmitting portion becomes the target value of the assist force. is there.

  According to the seventh aspect, since the drive means is feedback-controlled using the detection value of the assist force directly detected by the load sensor, slack, bending, extension or the like in the flexible auxiliary force transmission portion It is possible to effectively avoid the control error of the assist force caused by the above, and to apply the target assist force to the joint part of the user with excellent accuracy and stability.

  According to the present invention, since the assist force is changed by the output characteristic control means during the operation of the drive means, the assist force necessary for the target joint motion can be efficiently applied to the user. Furthermore, the influence of the assist force on the joint motion can be controlled by appropriately setting the peak position at which the assist force exerted by the drive means is maximized in accordance with the target joint motion.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the joint movement assistance apparatus as 1st embodiment of this invention, Comprising: (a) is a front view, (b) is a rear view, (c) is a side view. FIG. 2 is a block diagram showing an outline of a hardware configuration of the joint movement assisting apparatus shown in FIG. 1; Explanatory drawing for demonstrating model-wisely the effect | action of assist force with respect to the walking movement by the joint movement assistance apparatus shown by FIG. The graph for demonstrating the effect | action pattern of the assist force exerted by the assistance power transmission zone of the articulation assistance apparatus shown by FIG. The graph explaining the time-dependent change of a pedestrian's hip joint angle. The graph for demonstrating the application timing of the assist force in the joint movement assistance apparatus shown by FIG. FIG. 6 is a graph showing a change in output characteristics of the driving means with respect to a set value α in the joint movement assisting device shown in FIG. FIG. 2 is a control flow diagram for describing one aspect of operation control in the arthroplasty assist device shown in FIG. 1. FIG. 6 is a graph showing differences in walking speed, stride, and pace due to differences in setting value α in walking using the joint movement assistance device shown in FIG. 1. It is a figure which shows the joint movement assistance apparatus as 2nd embodiment of this invention, Comprising: (a) is a front view, (b) is a rear view, (c) is a side view.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a walking motion assist device 10, which is a first embodiment of an articulating motion assist device according to the present invention. The walking motion assisting device 10 is for assisting bending and stretching of a hip joint, and sandwiches the hip joint of the user at both end portions of the assisting force transmission bands 12 and 12 as a pair of assisting force transmitting parts extending left and right across the hip joint. A first attachment portion 14 attached to the thigh side where the femur is located, and a second attachment portion 16 attached to the lumbar side where the hipbone is located across the hip of the user It has the following structure. The left and right pair of auxiliary force transmission bands 12 and 12, the first mounting portions 14 and 14, the second mounting portion 16, and the electric motors 17 and 17 as a pair of driving means The assist member is configured. Note that, in FIG. 1, the walking motion assisting device 10 is illustrated in the state of wearing of the user, and the outline of the user is indicated by a two-dot chain line. In the following description, in principle, the front means the abdomen side (front) of the user, the back means the back side (rear) of the user, and the upper and lower directions are vertically and vertically. I say the upper and lower inside, respectively. Further, in the following description, the term "assist force" refers to an assist force that acts in a direction that compensates for the force required for the operation such as walking.

  More specifically, the auxiliary power transmission band 12 is formed of a flexible band and has a structure extending substantially linearly in the vertical direction across the hip joint in front of the user's left and right femurs. ing. The auxiliary power transmission band 12 of this embodiment is configured with a substantially single belt structure that extends linearly. And while the lower end part of each auxiliary power transmission belt 12 on either side is attached to the 1st wearing part 14 with which a user's thigh part side is mounted, the upper end part of each auxiliary power transmission belt 12 on either side is It is attached to the 2nd mounting part 16 with which a user's waist part is equipped.

The material of the auxiliary power transmission band 12 is preferably a deformable soft thin material, and in consideration of touch feeling, durability, air permeability, etc., in addition to woven fabric and non-woven fabric, leather, rubber sheet, resin sheet Etc. may be adopted appropriately. In particular, it is preferable that the assisting force transmission band 12 of the present embodiment is elastically deformable in the length direction (vertical direction in FIG. 1) in which the action direction of the tensile force by the electric motor 17 described later. it is desirable to have elasticity of about 0.3kgf / cm ² ~0.5kgf / cm ² in the length direction.

  In addition, a first mounting portion 14 is provided at the lower end portion of the auxiliary power transmission band 12. The first mounting portion 14 is in the form of a belt that is wound around the knee joint and mounted on the lower end side of the thigh, and in the present embodiment, is in the shape of a sports supporter used to protect the knee joint. ing. That is, the first mounting portion 14 is formed of, for example, a stretchable fabric and wound around the knee joint of the user, and fixed in position to the knee joint portion by the surface fasteners, snaps, hooks, etc. It is supposed to be worn. The first mounting portion 14 may be integrally formed with the auxiliary power transmission band 12 or may be separately formed from the auxiliary power transmission band 12 and may be post-fixed by bonding, stitching or the like. In addition, it can also consider that it does not prevent the bending and extension of a knee joint by forming the through-hole positioned in a user's kneecaps in the 1st mounting part 14. FIG.

  In addition, a second mounting portion 16 is provided at the upper end portion of the auxiliary power transmission band 12. The second mounting portion 16 has a single belt structure that is wound around the waist and mounted, and is formed of, for example, a stretchable cloth or the like in the same manner as the first mounting portion 14. It is wound around the waist and is mounted with its position fixed to the waist by means of hook and loop fasteners or snaps.

  The first mounting portion 14 and the second mounting portion 16 thus formed into a belt shape having a predetermined length are wound around the user and fixed with a hook-and-loop fastener etc. It is designed to be substantially fixed in position near the waist and near the waist.

  Furthermore, the lower end portions of the auxiliary force transmission bands 12, 12 disposed in front of the left and right thighs are fixed to the left and right first mounting portions 14, 14 by adhesion, welding, sewing or the like. Alternatively, they are attached by being integrally formed. The auxiliary force transmission bands 12, 12 are arranged to extend upward from near the knees on the front of the body in a state of being worn on the user.

  On the other hand, a pair of left and right electric motors 17 and 17 as driving means are fixedly fixed to the second mounting portion 16 at portions positioned above the hip joints of the left and right legs in the body front in the wearing state to the user. It is attached. Further, rotary shafts on which the rotational force is applied are provided in the electric motors 17 and 17 so as to extend in a substantially horizontal direction.

  Each electric motor 17 preferably employs a servomotor or the like capable of detecting the rotational position and controlling the amount of rotation in both forward and reverse directions. And the rotational drive force in the drive shaft of the electric motor 17 driven by electricity supply from the power supply device 18 is transmitted to the rotating shaft which is not shown in figure via a suitable reduction gear train. The rotation shaft is a rod-like member supported so as to be allowed to rotate in the circumferential direction, and the upper end portion of the auxiliary force transmission band 12 is fixed and wound around the outer peripheral surface thereof. The auxiliary force transmission band 12 is disposed across the hip joint.

  Then, when the rotation shaft (not shown) is rotated in one circumferential direction by the driving force exerted from the drive shaft of the electric motor 17, the auxiliary force transmission band 12 is wound around the rotation shaft. Thereby, the driving force by the electric motor 17 is transmitted in the length direction of the auxiliary power transmission band 12 and exerted as a tensile force between the first mounting portion 14 and the second mounting portion 16.

  In addition, by adopting a servomotor or the like provided with a rotary encoder 20 as an encoder as the electric motor 17, the amount of winding as the amount of pulling in the tension direction exerted on the auxiliary force transmission band 12 by the electric motor 17 is directly Can be detected. As a result, it is possible to provide traction amount control means that operates and controls the electric motor 17 based on the detection value by the rotary encoder 20 to control the traction amount of the auxiliary force transmission band 12 to a desired value. Then, in addition to the control based on the tensile force described below, the control based on the amount of take-up can be adopted together to improve the reliability of the control.

  On the other hand, when the rotating shaft is rotated in the other circumferential direction by the electric motor 17, the winding of the auxiliary force transmission band 12 by the rotating shaft is released and sent out, and the first mounting portion 14 and the second mounting portion 16 are The tension is released between the two.

  However, reverse rotation of the electric motor 17 is not essential, and by stopping the power supply to the electric motor 17 and making the output shaft of the electric motor 17 free, the pulling out of the auxiliary power transmission band 12 can be freely permitted. By setting the state, the tensile force between the first mounting portion 14 and the second mounting portion 16 may be released. According to this, with the movement by the user's muscle force, the assisting force transmission band 12 does not slack excessively and does not have tension enough to resist the movement, and easily follows the walking movement. Can be sent out.

  Further, the control of the electric motor 17 is executed by the control device 22 controlling the presence or absence of energization from the power supply device 18 to the electric motor 17 and the energization direction (rotation direction of the drive shaft of the electric motor 17). The control device 22 detects bending motion and extension motion of the user's hip joint based on the detection result (output signal) of the joint angle sensor 26 described later and the like, and the electric motor 17 is detected according to the detected hip movement. Control the power supply of Thereby, the tensile force exerted between the first mounting portion 14 and the second mounting portion 16 based on the driving force of the electric motor 17 is adjusted by the control device 22. The power supply device 18 and the control device 22 for controlling the power supply to the electric motors 17 and 17 to control the assist force exerted on the user by the auxiliary force transmission band 12 are the back side of the second mounting portion 16. Provided in

  Further, load sensors 24, 24 are attached to the left and right auxiliary power transmission bands 12, 12 at middle portions in the length direction. The load sensor 24 directly detects the load (stress) acting in the tensile direction. For example, the load sensor 24 is disposed at the dividing portion of the auxiliary power transmission band 12 and the divided portion of the auxiliary power transmission band 12 is a load sensor The connection via 24 allows all the tensile loads exerted on the auxiliary force transmission band 12 to be exerted on the load sensor 24.

  In addition, by attaching the load sensor 24 to the surface of the auxiliary power transmission band 12 or dividing only a part of the auxiliary power transmission band 12 in the width direction and interposing the load sensor 24 there, the auxiliary power can be obtained. A part of the tensile load exerted on the transmission band 12 may be exerted on the load sensor 24 as long as the load sensor 24 can detect the amount of change in the tensile load acting on the auxiliary force transmission band 12 when walking or the like.

  The type of load sensor 24 employed may be any load sensor that can detect the load acting on the auxiliary force transmission band 12, and a load sensor that converts the load directly into a voltage value by the load cell and outputs it may be suitably adopted. In addition to load cells such as magnetostrictive type, electrostatic capacity type, gyro type and strain gauge type, a load sensor using an elastic body such as a spring can be adopted.

  Furthermore, by providing the load sensor 24 on the electric motor 17 that applies a load to the auxiliary force transmission band 12, it is also possible to detect the force in the tension direction exerted on the auxiliary force transmission band 12 on the input side. Specifically, for example, by detecting a current value in a power feeding circuit for the electric motor 17, a load sensor 24 that detects a tensile force exerted on the auxiliary force transmission band 12 as a driving torque of the electric motor 17 is used. It is also possible to configure.

  In addition, joint angle sensors 26, which detect the inclination angle of the thigh as a bending angle of the hip joint, are respectively provided at portions positioned on the left and right thighs in a state of wearing on the user. The joint angle sensor 26 only needs to be capable of measuring the bending angle of the joint, and the type, structure, mounting position, and the like of the specific sensor are not limited. For example, as described in the above-mentioned Patent Document 1, a capacitance type sensor in which a pair of electrode films formed of a conductive elastic material is provided on both sides of a dielectric layer formed of a dielectric elastic material. It is also possible to arrange from the waist to the side of the body of the thigh.

  In the present embodiment, gyro sensors are employed as the joint angle sensors 26. As such a gyro sensor, a known one may be employed as a sensor for detecting a bending angle of a hip joint with respect to a hipbone-side hipbone held in a substantially vertical state by detecting an inclination angle of a thigh.

  For example, as a gyro sensor as the joint angle sensor 26, a general micro electro mechanical system (MEMS) sensor may be adopted, such as a three-axis angular velocity sensor capable of detecting an angular velocity of rotation about three orthogonal axes. . In addition to the gyro sensor, an acceleration sensor may be attached to the thigh and arithmetic processing may be performed on detection signals of both sensors to improve detection accuracy and to improve information. For example, it is possible to avoid the accumulation of errors in the reference direction by appropriately calibrating the reference direction in the detection value of the tilt direction by the gyro sensor with the acceleration sensor, and also the gravity direction detected by the acceleration sensor A three-dimensional inclination direction of the thigh is obtained by a four-dimensional number including a time axis by integrating and calculating the angular velocity of the thigh detected by the gyro sensor with respect to (vertical direction) by the computing device. Is also possible. Furthermore, in order to reduce detection errors due to noise or the like in the gyro sensor, it is also possible to employ filter means as a sensor fusion algorithm.

  Furthermore, in the present embodiment, when attaching the joint angle sensors 26, 26, fixing bands 28, 28 separate from the auxiliary force transmission bands 12, 12 are employed. That is, the joint angle sensor 26 is mounted on and supported by the fixing band 28 fixedly attached to the user's thigh, and the joint angle sensor 26 is mounted on the fixing band 28 and supported. It is fixedly attached to the rear side of the In addition, as the fixing band 28, an appropriate mounting structure such as a winding belt made of rubber or the like or a tightening belt made of a surface fastener can be adopted. Further, the attachment position of the joint angle sensor 26 may be set arbitrarily as long as the inclination angle of the thigh can be detected, and there is no hindrance to the movement of the user or the operation of the assisting force transmission band 12 or the like. The power source and arithmetic device required for the gyro sensor may be attached to the second attachment unit 16 or the like in addition to the attachment to the fixed bands 28 and 28.

Here, in the present embodiment, the control device 22 is provided with the following three control means, and performs these three controls.
(I) The bending of the hip joint detected by the joint angle sensor 26 when applying an assisting force to assist the leg muscle force at the time of walking by applying a tensile force to the assisting force transmission band 12 by the winding operation of the electric motor 17 Assist timing control means for determining start timing of winding operation of electric motor 17 as operation timing of driving means and continuation time of winding operation of electric motor 17 as operation time of driving means based on the value of the angle .
(II) The load level of the electric motor 17 is set such that the load acting on the auxiliary power transmission band 12 becomes the preset target value of the assist force during the application of the assist force described in (I) above. Assist force control means for feedback control and adjustment based on the detection value of the sensor 24.
(III) The load acting on the auxiliary power transmission band 12 is preset so as to eliminate the slack of the auxiliary power transmission band 12 during non-operation in which the assist force described in the above (I) is not applied. Sag prevention control means for feedback controlling the output level of the electric motor 17 based on the detection value of the load sensor 24 so as to obtain the target value of the bias force.

  That is, the control means of the electric motors 17, 17 by the control device 22 detects the detected values of the left and right hip joint angles detected by the joint angle sensor 26, and the tensile load of the left and right assist force transmission bands 12 detected by the load sensor 24. Power supply device comprising a secondary battery such as a portable battery so as to satisfy the control conditions of the electric motors 17 and 17 corresponding to the assist timing, the assist force, and the bias force set in advance with the detected value of Power supply to the electric motors 17 and 17 is performed from 18.

Specifically, for example, as a functional block diagram of the hardware is shown in FIG. 2, the control device 22 includes a controller 30 having storage means such as a ROM and a RAM, and a command value from the controller 30. The driver 32 is configured to supply electric power from the power supply device 18 to the electric motors 17 and 17 according to. That is, the control device 22 stores control programs in advance, and detects the hip joint angle obtained from the joint angle sensors 26 and 26 including the left and right gyro sensors, and the assistance obtained from the left and right load sensors 24 and 24 Based on the detection value of the tensile load exerted on the force transmission band 12, the functions of the aforementioned (I) assist timing control means, (II) assist force control means, and (III) slack prevention control means are realized. It is supposed to be. In the present embodiment, the power feeding control to the left and right electric motors 17, 17 is separately controlled, whereby the assist forces exerted on the left and right legs can be independently controlled.

  (I) The assist timing control means is configured by hardware and software, for example, as follows. That is, according to a program for assist timing control stored in advance in the ROM or RAM of the control device 22, the control device 22 uses the hip joint angles output from the left and right joint angle sensors 26, 26 as reference signals. When the hip joint angle of the power supply start stored in advance in the storage means (30) is reached, a signal of assist start is issued to start power supply from the power supply 18 to the electric motor 17. Further, in the assist timing control means of this embodiment, when the hip joint angle reaches the hip joint angle of the feed end stored in advance in the storage means (30) with the hip joint angle as a reference signal, the assist end signal is output. To stop the power supply from the power supply unit 18 to the electric motor 17. As described above, the assist timing control means of the present embodiment controls the timing of the start and end of the assist, and as a result, the assist time (the operation time of the electric motor 17) can be controlled. The control by the assist timing control means is executed under the condition that the walking state is determined by, for example, the hip joint angle output from the left and right joint angle sensors 26 changing in a predetermined cycle. It will be.

  (II) The assist force control means is configured by hardware and software, for example, as follows. That is, according to a program for assist force control stored in advance in the ROM or RAM of the control unit 22, the control unit 22 uses the tensile load obtained as the output value of the left and right load sensors 24 as a reference signal. Power supply from the power supply device 18 to the electric motor 17 is controlled so as to obtain the assist target value stored in advance in the storage means (30). The control by the assist force control means is executed on the condition that the assist timing control means has issued an assist start signal on the premise of, for example, a walking state.

  (III) The slack prevention control means is configured, for example, as follows by hardware and software. That is, according to a program for slack prevention control stored in advance in the ROM or RAM of the control device 22, the control device 22 uses the tensile load obtained as the output value of the left and right load sensors 24, 24 as a reference signal. Power supply from the power supply device 18 to the electric motor 17 is controlled so as to obtain the slack prevention target value stored in advance in the storage means (30). In addition, it is desirable that the target value for slack prevention be given, for example, with a substantially constant size to the extent that the user does not feel discomfort when walking. Further, the control by the slack prevention control means is, for example, from the time when the control of the tensile load by the assist force control means ends on the premise of the walking state until the next assist start signal is issued by the assist timing control means. It will be performed continuously over time.

  The controller 22 operates the electric motors 17 and 17 using (I) assist timing control means, (II) assist force control means, and (III) slack prevention control means, whereby the user walks. At the time of exercise, an assist force is made to act as a motion assist force around the hip joint through the assist force transmission bands 12 and 12 to perform walking assist. In particular, in the present embodiment, an assist operation is performed when the free leg is pulled forward during walking.

  That is, walking of a person is performed by alternately swinging forward and backward a pair of left and right legs X and Y as shown in a model diagram in FIG. In this walking motion, in order to maintain the kinetic energy for moving the center of gravity forward against the walking resistance due to the inclination of the walking surface, not only the energy such as weight support given by the muscle activity of the grounded leg X The movement of the free legs Y floating from the ground also plays an important role. Specifically, in the case of a leg extending backward during walking, the toe is separated from the ground behind the person's center of gravity and becomes a free leg Y, and only the leg X extending forward comes into contact with the ground. The walking is advanced. On the other hand, the free legs Y that have floated from the ground float up from the ground in a state of being greatly extended backward during walking, and also utilize the gravity acting on the free legs Y to move forward from the person's center of gravity Be thrown out. The pendulum movement by the swinging out of the free leg Y also acts as kinetic energy for advancing the center of gravity forward.

  However, in people with walking ability decline due to aging etc., the stride is small and the speed is small, so even when the free leg Y floats backward, sufficient gravity does not act and the effect by the pendulum motion of the free leg Y Is less likely to be exhibited. As a result, it is considered that a person with poor walking ability can not walk smoothly, and the walking itself becomes painful and does not walk, thereby further reducing leg muscle strength. Here, in the walking motion assisting apparatus 10 of the present embodiment, the free leg Y is assisted by assisting force F on the free leg Y at an appropriate timing so as to support pendulum motion with respect to the free leg Y. By promoting pendulum movement, the user's walking is given rhythm and efficiency. In particular, since the assist force F is applied to the free leg Y floating from the ground, the free leg Y can be efficiently displaced and moved with a small force to assist walking, and the weight can be reduced by grounding. In the support landing leg X, the muscular strength can be effectively trained by using the user's own muscular strength mainly.

The assist force F is exerted by the electric motor 17 through the assist force transmission band 12 as a tensile force around the hip joint of the user, and an example of a temporal pattern of the action force is shown in FIG. That is, during walking, as shown in FIG. 5, since the joint angle sensor 26 periodically detects a change pattern of the hip joint angle, the timing of the assist start is determined by the (I) assist timing control means, During the time from the assist start time to the assist end time, the magnitude of the assist force F is applied to the free leg Y while changing over time. In this embodiment, as shown in FIG. 5, the user's walking cycle S is determined based on the interval at which the detected value of the bending angle of the hip joint of the user is maximum, and the hip joint angle is maximum the timing predated by the calculated result amount obtained by multiplying a predetermined coefficient with respect to the walking period S from, and a timing t ₁ of the assist start. In addition, if a user's walking cycle is set based on the space | interval of the time of a hip joint angle value becoming the largest, a walking cycle can be recognized accurately. Also, two peaks in the profile of the hip joint angle shown in FIG. 5 indicate the point when the front peak swings the free leg forward to the maximum, and the free peak where the later peak swings out lands on the ground (heel contact) It is desirable to identify the walking cycle based on the interval at which the free leg is moved forward to the maximum.

Incidentally, the assist termination time t _2, for example be pre-set time from the assist start time t ₁ is set time as until the elapse of a possible, also, the detection value of the hip joint angle of the joint angle sensor 26 It is also possible to set as up to a preset angle value. In the present embodiment, by adding the calculation result obtained by multiplying a predetermined coefficient walking period S the assist start time t _1, to determine the assist end t _2, defines the assist action period T.

  In addition, as shown in FIG. 6, the action period T of the assisting force F from the assist start time to the assist end time is generally from the same time as the leg extending backward during walking leaves the ground and becomes a free leg. It is preferable to set the period slightly earlier than the time when it is swung forward and landed, that is, a period slightly shorter than the period of the free leg taking off. Preferably, the assist start time is within 10% of the application period T of the assist force F with respect to the time when the leg extending backward at the time of walking leaves the ground and becomes a free leg.

  Further, the magnitude of the target assist force F is controlled based on the target value set by the output characteristic setting means so that walking assistance can be efficiently performed while avoiding giving discomfort to walking. Be done. That is, the target value of the assisting force F set by the output characteristic setting means is set with a chevron profile having one peak in the middle in the acting period T of the assisting force F. Gradually (substantially continuously) with the elapsed time t of Then, the target assist force is such that the chevron profile is repeated at predetermined time intervals in response to the cyclic bending motion of the hip joint from the free leg Y to the ground contact leg X or from the ground contact leg X to the free leg Y , Or can be represented as a periodic waveform profile.

  Furthermore, in the output characteristic setting means, the target value of the assist force F is set as a function. That is, the assist force F is set to satisfy F = A * f (α, t). In the function, A is a parameter for setting the maximum value of the assist force F, and is appropriately set in advance by the maximum output setting means. The maximum output setting means is a means for inputting a set value A which determines the size of the assisting force for assisting the leg muscle strength of the user and enabling change setting, and, for example, an external input device such as a dial or a ten key And setting means for setting the set value A in a mathematical expression indicating a target value of the assist force F in accordance with an input from the external input device. The maximum output setting means may set the setting value A manually by the user using the external input device as described above, or automatically set the setting value A based on the detection result of the sensor or the like. You may do so. Further, f (α, t) is a function of a setting value α which is preset by a peak position setting means described later and an elapsed time t from the start of the action of the assist force.

  Particularly, in the output characteristic setting means of the present embodiment, the target value of the assist force F is set as a sine function, and the assist force F satisfies F = A * sin (πt / T + α * sin (πt / T)) Is set as. In short, the function f (α, t) of the present embodiment is a sine function, and f (α, t) = sin (πt / T + α * sin (πt / T)).

Here, the alpha of the sine function, a parameter for changing setting a peak position t ₃ of the assist force F, arbitrarily or selectively set in the range of -1 ≦ α ≦ 1 by the peak position setting means It is made possible. By adjusting this setting alpha, peak position t ₃ of the assist force F is adapted to be adjusted at the working period T of the assist force F. The peak position setting means provided in the output characteristic setting means is a means for inputting the set value α and making it possible to change and set, for example, an external input device such as a dial or a ten key and an input from the external input device. There is provided setting means for setting a set value α of a mathematical expression indicating a target value of the assist force F accordingly. The peak position setting means may set the setting value α manually by the user using the external input device as described above, or automatically set the setting value α based on the detection result of the sensor or the like. You may do so.

That is, as shown in the graph of FIG. 7, changing the range numerically the -1 ≦ α ≦ 1 setting alpha, when the set value alpha is 0, the assist force is the peak position t ₃ of the assist force F It is set at the center of the action period T of F, and the output characteristic is substantially symmetrical before and after the peak. Further, when the setting value α takes a positive number, while the peak position t ₃ is set in the first half than in the middle of the action period T of the assist force F, when the setting value α takes a negative number , the peak position t ₃ is set in the second half than the center of the action period T of the assist force F. In the graph of FIG. 7, when α increases from −1 to 0.25 by 1, how the assist force F changes with respect to the elapsed time t from the start of the action of the assist force F It is shown that as the value of α approaches 1, the peak position approaches the time point of application of the assist force, and the output characteristic changes so that the assist force F reaches the peak at a shorter elapsed time t.

Also, in the assist force F defined by F = A * f (α, t), the function f (α, t) is sin (πt / T + α * sin (πt / T)) While the assist force F is 0 at both the action start time t ₁ and the action end time t ₂ of the force F, the assist force F gradually increases from the action start time t ₁ to the peak position t ₃ and gradually decreases from the position t ₃ to end-of-work time t _2.

Here, by a changeable Thus the peak position t _3, and may be modified into the effect of assisting force is given to the gait of the user. That is, setting the peak position t ₃ of the assist force in the first half of the duration of action T of the assist force (α> 0) and, when setting the peak position t ₃ of the assist force to the center of action period T (alpha = 0) As the stride length increases, the number of steps per unit time decreases and the pace becomes slower. On the other hand, set in the second half of the duration of action T peak position t ₃ of the assist force and (α <0), compared with the case of setting the peak position t ₃ of the assist force to the center of action period T (alpha = 0) As the stride length decreases, the number of steps per unit time increases and the pace becomes faster. In short, if setting the set value α to a positive value and applying the assisting force to the user, the stride walking method in which the distance traveled in one step is large results in setting the set value α to a negative value for the user When the assist force is applied, the pitch stepping method takes a short time for one step. As the absolute value of α increases, the difference in stride and pace with respect to the case of α = 0 increases, and the influence of the assist force on the gait increases.

  Therefore, by changing the numerical value of the set value α by the peak position setting means and changing the peak position (waveform) of the target value of the assist force, the gait of the user who received the assist force can be controlled to some extent If, for example, α is set to a positive value, it is possible to reduce the number of times the leg is moved to reduce the burden on cardiopulmonary function, etc. If α is set to a negative value, the hip joint It is possible to reduce the change in angle and to reduce the burden on the leg muscle strength. On the other hand, if α is set to a positive value, the angle change of the hip joint becomes large, so that the leg muscle strength can be efficiently trained, and if α is set to a negative value, the number of times to move the leg is With the increase, it will also be possible to train cardio function effectively.

  In addition, since f (α, t) = sin (πt / T + α * sin (πt / T)), the maximum value of the assist force F depends on the magnitude of the set value A by the maximum output setting means. It is supposed to be decided. Thereby, the maximum value of the assist force F is adjustable by the set value A which is a parameter independent of the set value α set by the peak position setting means, and the set value A is appropriately adjusted by the maximum output setting means. By setting to, it is possible to easily set the assist force F of the required size.

  As described above, in the walking exercise assisting apparatus 10 according to the present embodiment, the assist is performed by adjusting two parameters of the setting value A set by the maximum output setting unit and the setting value α set by the peak position setting unit. The output characteristics of the force can be easily adjusted and set, and the target assist force can be obtained easily and accurately.

  Moreover, the magnitude of the assisting force F exerted on the leg through the assisting force transmission band 12 is directly detected by the load sensor 24 provided in the assisting force transmission band 12, and the magnitude of the detected actual assisting force is a target The electric motor 17 is feedback-controlled based on the detection value of the load sensor 24 so that the magnitude of the assist force to be obtained is obtained. Therefore, the magnitude of the target assist force as illustrated in FIGS. 4 and 6 can be realized with high accuracy.

  In addition, except for the situation where the assist force transmission band 12 is taken up by the electric motor 17 as described above and the assist force by tension is applied and controlled, the electric power motor 17 does not operate and the assist power transmission band 12 has a certain length. When left at rest, slack and excessive tension occur in the assist force transmission band 12 as the user walks. Therefore, in the present embodiment, while the assist force is not acting, (III) the electric motor 17 is controlled by the slack prevention control means so that a small tensile force substantially constant with respect to the assist force transmission band 12 is used as the slack prevention force. It is kept in the state of being exerted. At the time of control of this slack prevention, referring to the detection value of the load sensor 24 which directly detects the tensile stress of the auxiliary force transmission band 12, the electric motor 17 is controlled so that the detection value becomes a target constant tensile force. Are feedback controlled.

  In addition, by performing such slack prevention control, as shown in FIG. 4, the assist force transmission band 12 is provided over substantially the entire period except the application period T of the assist force F. A predetermined biasing force (small tensile force) is exerted. And by thus preventing slack of the assist force transmission band 12 at all times, for example, (I) at the time when assist is started by the assist timing control means, (II) assist set in the assist force control means When the force F is applied, the tensile force by the auxiliary force transmission band 12 immediately rises with the operation of the electric motor 17. Therefore, the target assist force can be applied to the free leg with almost no time delay, and the assist force can be accurately applied to the free leg in a pattern suitable for walking.

  In particular, in the present embodiment, even during the application of the assist force F, (II) the tensile force of the assist force transmission band 12 is directly feedback controlled by the detected value of the load sensor 24 by the assist force control means. In addition to the quick start-up at the start, control problems such as insufficient assist force F, overshoot, and divergence are also effectively prevented, and high-accuracy followability to the target value can be achieved together. .

  Incidentally, the entire flow of the walking assist control as described above by the walking motion assisting apparatus 10 of the present embodiment will be described according to a flow chart of FIG. 8 showing one control mode.

  First, when control is started in step S1, sensor calibration such as origination is performed for the joint angle sensor 26 and the load sensor 24 in the initialization step of step S2, and then an auxiliary force transmission band for slack prevention in step S3. The bias force of the load sensor 24, which is set as a target value, is set when performing control to apply a bias force to T.12.

  Next, in step S4, a pattern of a target value of assist force for assisting muscle power during walking (a profile of temporal change in magnitude of assist force as shown in FIGS. 4 and 6) is set. That is, in step S4, the magnitude of the assist force is set by setting the set value A for the maximum value of the assist force by the maximum output setting means and setting the set value α for the peak position of the assist force by the peak position setting means. Set the change profile over time. The set values A and α are set by manual input or automatic input based on the detection value of the sensor, etc., and in the present embodiment, it is possible to change numerical values either continuously or stepwise. . Furthermore, the set value A and the set value α may be separately settable, and a plurality of combinations of the set value A and the set value α may be preset according to the type of exercise to be performed. Alternatively, the setting may be selected from the combination of the preset setting values A and α.

  Thereafter, in step S5 and subsequent steps, drive control of the electric motor 17 is executed to start the assist operation. The following control of the electric motor 17 may be performed alternately for each of the target left and right legs, or may be provided with an independent control system for each of the left and right legs.

  That is, in step S5, while detecting the detected values of the hip joint angle in the left and right legs from the left and right joint angle sensors 26, 26, the detection of the tensile force of the left and right auxiliary force transmission bands 12, 12 from the left and right load sensors 24, 24. A value is acquired, and signal processing such as storing in the RAM of the control device 22 as an angle signal or an assist force signal is performed. In the following step S6, based on the detection results of the left and right joint angle sensors 26, 26 obtained in step S5, a change in the hip joint angle of the left and right legs is detected to grasp the present condition of the wearer.

  Then, in step S7, it is determined whether or not the present state of the wearer is in the walking state, and if it is determined that it is not in the walking state, the bias force set in step S3 is set as the control target value in step S8. After that, step S9 is executed, and the electric motor 17 is operated and controlled using the detection value of the load sensor 24 as a reference signal so that the control target value becomes the tensile force of the auxiliary force transmission band 12 A constant anti-slack force (biasing force) is exerted on the transmission band 12.

  Further, until it is determined in step S10 that the assist control operation has ended by the input from a switch or the like that cuts off the power supply from the power supply, the control of steps S5 to S9 is repeatedly executed at predetermined intervals. By this, the above-mentioned constant anti-slack force is kept applied until walking is started.

On the other hand, when it is determined in step S7 that the current state of the wearer is in the walking state, the process proceeds to step S11, and the acting period T of the assist force based on the detected value of the hip joint angle detected by the joint angle sensor 26. It is determined whether or not it is (see FIGS. 5 and 6). If it is determined that not the action period T of the assist force, at step S12, whether or not reached assist start time t ₁ based on the angle of the hip joint, which is detected by the joint angle sensor 26 is determined.

Based on the detected angle value of the hip joint, if it is determined not yet reached the assist start point t _1, the process proceeds to step S8, the flow returns to the control loop for causing a slack limiting force described above (bias force) .

On the other hand, if it is determined in step S11 that the assist force is being applied during the application period T of the assist force (see FIGS. 5 and 6), the process proceeds to step S13 and the end of the application period T of assist force is completed. It is determined whether it is before or not. Incidentally, the end of the working period T of the assist force, the input in step S4, for example, time data and from the assist start time t ₁ to assist the end t _2, such as by the value of the hip joint angle that is determined to assist completion It can be determined.

  Then, if it is determined in step S13 that the assist period T has not ended, or if it is determined in step S12 that the assist period T has been started, the process proceeds to step S14 and assist force generation control is performed. . For this purpose, first, in step S14, the assist force at the current time point is determined and determined using the pattern of the assist force input in step S4, and set as a target value. Thereafter, the process proceeds to step S9, and the electric motor 17 is operated and controlled using the detection value of the load sensor 24 as a reference signal such that the control target value becomes the tensile force of the auxiliary force transmission band 12. An assist force is exerted on the band 12.

  Then, the control including the steps S11 to S14 is repeatedly performed at predetermined intervals until it is determined in step S10 that the assist control operation has ended, so that the control is preset for the assist period T. The control of the assist force is executed by the pattern of the assist force. If it is determined in step S13 that the assist period T has ended, as in the case where it is determined in step S12 that the assist start point has not yet been reached, the process proceeds to step S8 and the above-mentioned slack prevention force Return to the control loop to generate (bias force).

  As described above, the control operation of the bias force and the assist force by the feedback control of the electric motor 17 is determined in step S10 that the assist control operation is completed, and is continued until it is reached in step S15.

  When the walking motion assisting apparatus 10 according to the present embodiment as described above is worn, part of the force required for bending the hip joint is based on the generated force of the electric motor 17 of the assisting force transmission bands 12 and 12. It will be compensated by the assist force exerted on the user's leg as a tensile force. Therefore, for example, when performing a motion to bend the hip joint and carry the rear foot forward while walking, it is possible to perform the desired operation with a small muscle force, and the user performs the operation by aging or injury or illness. Even when the user does not have sufficient muscle strength, it is possible to smoothly perform the intended walking motion and to prevent the user's activity from being restricted.

  Further, the auxiliary force transmission band 12 provided on the path for transmitting the generated driving force of the electric motor 17 to the legs of the user as the assist force is made flexible, and more preferably in the force transmission direction. It is made elastically deformable. Thereby, the generated driving force of the electric motor 17 is relieved by the flexible deformation and elasticity of the auxiliary force transmission band 12 and then exerted on the leg of the user. Therefore, compared with the case where the generated driving force of the electric motor 17 is directly transmitted by the transmission system having a rigid skeletal structure, the load on the joints of the user is reduced and the muscle is afflicted. Can be prevented.

  Furthermore, the target value of the assist force output by the electric motor 17 is controlled by the output characteristic setting means so as to form a chevron profile that changes in accordance with the elapsed time from the assist start time. The corresponding assist power can be applied appropriately. In particular, by setting the action start time point and the action end time point of the assist force in accordance with the cycle of the walking motion, it is possible to apply the assisting force in accordance with the walking motion.

  Moreover, in the present embodiment, the load actually acting on the leg portion of the user is directly measured by the load sensor 24, and the difference between the actual assist force and the target value of the assist force is based on the measured value. Since the output of the electric motor 17 is feedback-controlled so that the value of V is reduced, it is possible to apply a highly accurate assist force closer to the target value to the user.

  Further, the target maximum value of the assist force output by the electric motor 17 can be appropriately changed and set by the maximum output setting means of the output characteristic setting means. Therefore, depending on the user's muscular strength and the desired exercise, an assisting force of an appropriate size can be applied to effectively assist the user's walking. In the present embodiment, in particular, the target value of the assist force F is set to F = A * sin (πt / T + α * sin (πt / T)), so the target maximum value of the assist force is set by the maximum output specifying means. It is determined in accordance with the set value A, and the assist force can be easily adjusted.

  Furthermore, in the present embodiment, since the function f (α, t) = sin (πt / T + α * sin (πt / T)) is a sine function, the target value of the assist force F at the initial position is 0 And the assist force F is controlled to gradually increase toward the peak position. Therefore, the rapid rise of the assist force is avoided, and the durability is improved by preventing an excessive load from acting on the electric motor 17 and the transmission system of the assist force, and the user's sense of discomfort with respect to the assist force Is also reduced. Similarly, at the end of the assist, the target value of the assist force F is 0, and the assist force is controlled so as to gradually decrease from the peak position toward the end of the assist. Uncomfortable feeling can be reduced.

  Further, the peak position of the assist force output by the electric motor 17 can be appropriately changed and set within the application period T of the assist force by the peak position setting means of the output characteristic setting means. Therefore, the influence of the assisting force on the walking motion of the user can be controlled to some extent by changing the peak position of the assisting force, and the cardiopulmonary function by reducing the load of cardiopulmonary function or leg muscle power or increasing the load. Alternatively, efficient training of leg muscle strength can be appropriately selected and realized. It is needless to say that the influence on the walking movement based on the difference in the peak position of the assist force may be selected not only according to the target exercise but also according to the preference of the user.

  In addition, the change of the gait based on the difference of setting value (alpha) by such a peak position setting means was confirmed by experiment, as shown in FIG. FIG. 9 shows the results of a walking experiment performed on three test subjects (users) in order to confirm the effect of the walking motion assisting apparatus 10 according to the present embodiment. The contents of the experiment and the results are described below.

  First, while the subject got used to the walking exercise assisting apparatus 10, in order to confirm a walking speed and the like comfortable for the subject, a training walk of about 10 minutes was performed before the walking experiment. At that time, the setting value α was changed by the peak position setting means, and the condition that the subject felt that the assist force most effectively acted was confirmed in the cases of α> 0 and α <0. As a result, we adopt α = 1 for α> 0 and α = −0.5 for α <0, because the assist power is effective, and add the case of α = 0 to them. A walking experiment was conducted for the three set values α. Moreover, the same walking experiment was performed also when the assist force was set to 0, and the effectiveness of the assist force of the walking movement assistance apparatus 10 was confirmed.

  In the walking experiment, with no assist power, with assist power and with α = 0, with assist power and with α = 1, with assist power and with α = −0.5, each 20 m The subject made five rounds of the square-shaped walking course, and measured the stride at the time of walking and the number of steps (steps) per unit time. In addition, the walking speed which can be changed by adjustment of the setting value A by the maximum output setting means adopted the speed that the subject was comfortable in the previous walking practice. Also, for the purpose of improving the accuracy of the experimental results, the above-mentioned walking experiment was performed twice for each condition.

  And the average value of the measurement result of the stride and the number of steps (step) per unit time in the above-mentioned walking experiment is shown as a graph in FIG. According to this, as compared with the case where the assisting force is not applied, when the assisting force is applied, the stride length is increased and the number of steps per unit time is also increased. From these results, by applying the assist force using the walking motion assisting apparatus 10 according to the present embodiment, the walking speed is increased, the movement becomes smooth, and the walking can be performed with a more active gait. That has been confirmed.

  Furthermore, according to FIG. 9, it can also be understood that the gait of the subject changes in accordance with the change of the set value α by the peak position setting means in the use state of the walking motion assisting device 10. That is, in the case of α = 1, as compared with the case of α = 0, the stride length is increased, and the number of steps per unit time is decreased, and the pace is gradual. On the other hand, in the case of α = −0.5, the stride is smaller than in the case of α = 0, and the number of steps per unit time is increased to make the pace faster. Thus, it was confirmed by experiments that the stride walking method is used when α> 0 and the pitch walking method is used when α <0.

  Although the embodiments of the present invention have been described above in detail, the present invention is not limited by the specific description. For example, the first attachment portion can also be attached to the thigh above the knee joint, which makes it possible to make the device compact. However, the joint movement assisting device of the present invention is not limited to the movement assistance around a hip joint, and is also applicable to the movement assistance around joints such as elbows and shoulders, for example. Specifically, for example, when the user performs a rehabilitation exercise accompanied by periodic joint flexion such as push-up or shoulder-spindle-like exercise, exercise assistance can be performed by applying an assist force like walking.

  Further, the mounting positions of the control device and the power supply device are not limited. For example, they are housed in the pocket of the user's clothes as an independent structure connected by the lead wire for energization, or put on the shoulder of the user It is also possible to wear it. In the case where an assisting force is applied to an exercise that does not move the place by using a walking machine, it is also possible to supply power from an installation battery or a household power outlet.

  Furthermore, the auxiliary power transmission unit is not necessarily limited to one that is entirely flexible (flexible), and may have a hard portion formed of a metal, a synthetic resin, or the like if it is partial. Furthermore, even when the assisting force transmitting portion is resilient, the entire assisting force transmitting portion may be elastically deformable in the force transmitting direction, or the assisting force transmitting portion may be elastically deformed in the force transmitting direction. It may be partially acceptable.

  Furthermore, the auxiliary power transmission unit is not limited to the one belt-shaped auxiliary power transmission band 12 as shown in the above embodiment, and for example, as shown in the above-mentioned Patent Document 2, A structure in which the first traction band and the second traction band are connected to each other by a connection fitting may be employed.

  Further, the mounting position of the joint angle sensor is not particularly limited as long as it can measure the bending angle of the target joint. That is, it is not necessary to mount the joint angle sensor on the rear side of the thigh as in the above embodiment, and for example, as shown in FIGS. 10 (a) to 10 (c), joint angles of a gyro sensor etc. The sensors 26, 26 may be mounted at any position, such as near the lower end on the front side of the user's thigh. Further, as shown in FIGS. 10 (a) to 10 (c), the joint angle sensor 26 may be used, for example, in the first mounting portion 14 or the like without adopting the special fixing band 28 as in the above embodiment. It is also possible to attach. However, when the joint angle sensor 26 is attached to the assisting force transmission band 12, since the inclination angle of the thigh and the high accuracy do not match, the thigh like the fixed end with the first mounting portion 14 It is desirable to reduce the measurement error of the flexion angle of the hip joint by mounting it on a portion that is inclined substantially equal to the portion.

  Further, the formula of the target value of the assist force F shown in the above embodiment is merely an example and is not particularly limited, and f (α, t) is not necessarily limited to a sine function. Furthermore, in the above embodiment, although the target value of assist force is set with a chevron profile in which only one peak appears in the assist action period T, the target value of assist force is a chevron profile having two or more peaks. The change profile of the target value may be set appropriately in accordance with the difference in the target joint motion or the like.

  Further, in the embodiment, the assist force which is an external force exerted on the human body is directly detected by the load sensor 24, but the assist force exerted by the drive means corresponds to the output of the drive means. The output of the drive means becomes a predetermined target value by detecting the power consumption of the electric motor 17 or the like and detecting the output of the drive means as the assist force or controlling the supply voltage of the electric motor 17 It is also possible to control as an assist force.

10: walking motion assistance device (articulation assistance device), 12: assist force transmission band (assist force transfer portion), 14: first mounting portion, 16: second mounting portion, 17: electric motor (driving means) , 22: controller, 24: load sensor, 26: joint angle sensor

Claims (7)

A flexible auxiliary power transmission unit, a first mounting unit provided at one end of the auxiliary power transmission unit and mounted on one of the parts sandwiching a user's joint, and the auxiliary power transmission unit A second mounting portion provided at the other end of the housing and mounted on the other part of the user sandwiching the joint, and driving means for applying an assisting force in the tension direction to the auxiliary force transmitting portion; An articulation support system comprising: a joint angle sensor for detecting a bending angle of the joint of the user; and assist timing control means for determining an operation timing of the drive means based on a detection value of the joint angle sensor. ,
Output characteristic setting means for setting a target value of the assist force by the drive means is provided, and the target value of the assist force set by the output characteristic setting means is an operating time of the drive means within a cycle of periodic motion Set with a chevron-shaped profile that changes with the passage of
The output characteristic setting means capable of target value of the assist force is set by changing the peak position of maximum, in the front-rear direction of the elapsed time in round single cycle of movement in the walking cycle for one step of the unit An articulation support apparatus comprising peak position setting means. The assist timing control means measures a cycle of joint movement of the user based on an interval of time in which a detected value of a bending angle of the joint by the joint angle sensor is maximum.
The joint movement assisting apparatus according to claim 1, wherein the assist timing control means sets an operation time of the drive means based on a cycle of the joint movement. The joint motion assisting device according to claim 1 or 2, wherein the output characteristic setting means includes maximum output setting means for setting a maximum value of the target value of the assist force at the peak position. The joint motion assisting device according to any one of claims 1 to 3, wherein the target value of the assist force is gradually changed by the output characteristic setting means as the actuation time of the drive means elapses.   The target value of the assist force F when time t has elapsed from the start of actuation of the drive means, the set value A set by the maximum output setting means for setting the maximum value of the target value of the assist force, and the peak The function f (α, t) of the setting value α set by the position setting means and the elapsed time t satisfies F = A · f (α, t) according to any one of claims 1 to 4. Joint movement device.   The articulation support system according to claim 5, wherein the function f (α, t) is a sine function.   A load sensor is provided for detecting a load in the tensile direction acting on the auxiliary force transmitting portion, and a load acting on the auxiliary force transmitting portion is a target value of the assist force based on a detected value of the load sensor. The articulation assistance device according to any one of claims 1 to 6, wherein the operation of the drive means is feedback controlled.