WO2025070425A1 - Link mechanism device and robot - Google Patents

Abstract

Provided is a link mechanism device which is driven by a smaller number of drive parts than the number of a plurality of four-bar link mechanisms and can be driven to follow the shape of an object. The link mechanism device includes a plurality of four-bar link mechanisms linked to each other, and a drive unit for driving the four-bar link mechanisms. The drive part is connected to at least one of a first outer joint part joining an end part of a first outer link with an end part of a first drive side link, and a first inner side joint part joining the end part of the first drive side link with an end part of a first inner side link, and drives a first four-bar link mechanism in such a manner that the relative position between the first outer joint part and the first inner side joint part can be varied. When the length of a second outer link is A1, the length of a second drive side link is B1, the length of a second inner side link is C1, and the length of a second tip side link is D1, A1 + B1 > C1 + D1 is satisfied.

Description

Link mechanism device and robot

This disclosure relates to a link mechanism device and a robot.

　Link mechanism devices having multiple four-bar link mechanisms that are connected together have been known for some time. Patent Document 1 also discloses a configuration that specifies the length of the links included in the four-bar link mechanism.

Patent No. 6948647

However, in conventional link mechanism devices, in order to drive multiple four-bar link mechanisms so as to follow the shape of an object, the same number of drive units as the number of four-bar link mechanisms may be required. If the same number of drive units as the number of four-bar link mechanisms is installed, the link mechanism device will become expensive, and the size and weight of the link mechanism device will increase, and the configuration of the link mechanism device may become complicated.

The technology disclosed herein aims to provide a link mechanism device that can drive multiple four-bar link mechanisms to follow the shape of an object using a number of drive units that is fewer than the number of four-bar link mechanisms.

A link mechanism device according to one embodiment of the present disclosure has a plurality of four-bar link mechanisms connected to each other and a drive unit for driving the four-bar link mechanisms, the plurality of four-bar link mechanisms including a first four-bar link mechanism connected to the drive unit and a second four-bar link mechanism connected to the first four-bar link mechanism, the first four-bar link mechanism including a first outer link located on the opposite side to the object when in contact with the object, a first drive side link located on the drive unit side, a first inner link located on the object when in contact with the object, and a first tip side link located on the opposite side to the drive unit, the second four-bar link mechanism including a second outer link located on the opposite side to the object when in contact with the object, The drive unit includes a second drive side link located on the drive unit side, a second inner link located on the object side when it contacts the object, and a second tip side link located on the opposite side to the drive unit side. The drive unit is connected to at least one of a first outer node portion that connects the end of the first outer link and the end of the first drive side link, and a first inner node portion that connects the end of the first drive side link and the end of the first inner link, and drives the first four-bar link mechanism to vary the relative position of the first outer node portion and the first inner node portion. If the length of the second outer link is A1, the length of the second drive side link is B1, the length of the second inner link is C1, and the length of the second tip side link is D1, A1 + B1 > C1 + D1 is satisfied.

According to one aspect of the present disclosure, a link mechanism device can be provided that can drive multiple four-bar link mechanisms to follow the shape of an object using a number of drive units that is fewer than the number of the multiple four-bar link mechanisms.

1 is a schematic diagram illustrating a configuration example of a link mechanism device according to a first embodiment. FIG. 5A to 5C are schematic diagrams illustrating an example of the operation of the link mechanism device according to the first embodiment. FIG. 2 is a schematic diagram illustrating a configuration example of a link mechanism device according to a first comparative example. 5A to 5C are schematic diagrams illustrating an example of the operation of a link mechanism device according to a first comparative example. FIG. 13 is a schematic diagram showing a configuration example of a link mechanism device according to a second comparative example. 13A to 13C are schematic diagrams illustrating an example of the operation of a link mechanism device according to a second comparative example. FIG. 13 is a schematic diagram illustrating an example of the configuration of a link mechanism device according to a second embodiment. 13 is a first schematic diagram illustrating an example of an operation of the link mechanism device according to the second embodiment. FIG. FIG. 11 is a second schematic diagram illustrating an example of the operation of the link mechanism device according to the second embodiment. FIG. 13 is a schematic diagram showing a configuration example of a link mechanism device according to a first modified example. FIG. 13 is a schematic diagram showing a configuration example of a link mechanism device according to a second modified example. FIG. 13 is a schematic diagram showing a configuration example of a link mechanism device according to a third modified example. FIG. 13 is a schematic diagram showing a configuration example of a link mechanism device according to a fourth modified example. FIG. 13 is a schematic front view showing an example of a robot according to a third embodiment. FIG. 13 is a schematic side view illustrating an example of a robot according to a third embodiment. 16A is a schematic cross-sectional view taken along line XVI-XVI in FIG. 16.

Below, an embodiment of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same components are given the same reference numerals, and duplicate explanations will be omitted as appropriate.

The embodiments shown below are examples of link mechanism devices and robots for embodying the technical ideas of the present disclosure, and are not intended to limit the present disclosure to the embodiments shown below. Unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described below are intended as examples, and are not intended to limit the scope of the present disclosure to those alone. Furthermore, the sizes and positional relationships of the components shown in the drawings may be exaggerated for clarity of explanation.

[First embodiment]
<Configuration of link mechanism device according to first embodiment>
A link mechanism device according to a first embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a schematic diagram showing an example of a configuration of a link mechanism device 200 according to the first embodiment. Fig. 2 is a schematic diagram showing an example of an operation of the link mechanism device 200.

The link mechanism device 200 has a plurality of four-bar link mechanisms 210 that are connected to each other, and a drive unit 220 that drives the four-bar link mechanisms 210. The plurality of four-bar link mechanisms 210 include a first four-bar link mechanism 211 that is connected to the drive unit 220, and a second four-bar link mechanism 212 that is connected to the first four-bar link mechanism 211.

The first four-bar link mechanism 211 includes a first outer link L11 that is located on the side opposite the object S when it comes into contact with the object S, and a first drive side link L12 that is located on the drive unit 220 side. The first four-bar link mechanism 211 also includes a first inner link L13 that is located on the side of the object S when it comes into contact with the object S, and a first tip side link L14 that is located on the side opposite the drive unit 220 side.

The second four-bar link mechanism 212 includes a second outer link L21 that is located on the side opposite the object S when it comes into contact with the object S, and a second drive side link L22 that is located on the drive unit 220 side. The second four-bar link mechanism 212 also includes a second inner link L23 that is located on the side opposite the object S when it comes into contact with the object S, and a second tip side link L24 that is located on the side opposite the drive unit 220 side.

The drive unit 220 can be connected to at least one of the first outer node J11 that connects the end of the first outer link L11 to the end of the first driving side link L12, and the first inner node J12 that connects the end of the first driving side link L12 to the end of the first inner link L13. The drive unit 220 drives the first four-bar link mechanism 211 to vary the relative position between the first outer node J11 and the first inner node J12.

If the length of the second outer link L21 is A1, the length of the second driving side link L22 is B1, the length of the second inner link L23 is C1, and the length of the second tip side link L24 is D1, then A1+B1>C1+D1 is satisfied. In this specification, "link length" refers to the length in the direction from the node at one end of the link to the node at the other end when the link and another link are connected to each other at a node. Also, if the link has a non-linear shape, the length of the link refers to the linear distance between the nodes at both ends of the link. If the link is flexible, the distance between the nodes when the link is placed on a flat surface is considered to be the length of the link.

In the link mechanism device 200 illustrated in Figures 1 and 2, when the first four-bar link mechanism 211 comes into contact with the object S by being driven by the drive unit 220, the second four-bar link mechanism 212 connected to the first four-bar link mechanism 211 on the tip side is driven by forces T21 and T22 generated in response to this contact. The driven second four-bar link mechanism 212 comes into contact with the object S. Note that the tip side refers to the end side of the link mechanism device 200 opposite the drive unit 220 side.

A more detailed explanation will be given. In the example shown in FIG. 1, a force F1 is applied from the drive unit 220 to the first outer node J11 in a direction toward the tip side. The application of force F1 causes the first outer node J11 to move toward the tip side. As the first outer node J11 moves toward the tip side, a force T11 that rotates the first inner node J12 around the first inner node J12 acts on the first drive side link L12, causing the first drive side link L12 to fall toward the object S. As the first outer node J11 moves toward the tip side, a force T12 that rotates the first inner node J12 around the first inner node J12 acts on the first inner link L13, causing the first inner link L13 to fall toward the object S. As a result, the first inner link L13 comes into contact with the object S.

When the first inner link L13 comes into contact with the object S, as shown in FIG. 2, a force T21 acts on the second drive side link L22 to rotate it around the second inner node J22, causing the second drive side link L22 to fall towards the object S. Furthermore, when the first inner link L13 comes into contact with the object S, a force T22 acts on the second inner link L23 to rotate it around the second inner node J22, causing the second inner link L23 to fall towards the object S. As a result, the second inner link L23 comes into contact with the object S.

In the link mechanism device 200, the force generated by the four-joint link mechanism 210 located on the drive unit 220 side coming into contact with the object S acts sequentially on the four-joint link mechanism 210 connected to the tip side. This allows the tip side four-joint link mechanism 210 to come into contact with the object S sequentially. By the four-joint link mechanism 210 coming into contact with the object S sequentially from the drive unit 220 side to the tip side, the multiple four-joint link mechanisms 210 take a shape that follows the shape of the object S. In this way, the link mechanism device 200 can drive the multiple four-joint link mechanisms 210 so as to follow the shape of the object S. In other words, in this embodiment, a link mechanism device 200 can be provided that can drive the multiple four-joint link mechanisms 210 so as to follow the shape of the object S using a number of drive units 220 that is smaller than the number of the multiple four-joint link mechanisms 210. From another perspective, the link mechanism device 200 forms a so-called underactuated arm, and can drive the multiple four-joint link mechanisms 210 so as to follow the shape of the object S.

In the example shown in Figures 1 and 2, the object S is a sphere. The link mechanism device 200 can drive the two four-bar link mechanisms 210 so that they follow the shape of the sphere, which is the object S. However, the object S is not limited to a sphere and may be an object having any shape. For example, the object S may be a human torso. The link mechanism device 200 can wrap the two four-bar link mechanisms 210 around the human torso by driving the two four-bar link mechanisms 210 so that they follow the shape of the human torso, which is the object S.

In addition, the link mechanism device 200 can drive the four-bar link mechanism 210 with a number of drive units 220 that is fewer than the number of the multiple four-bar link mechanisms 210. In the example shown in Figures 1 and 2, there is one drive unit 220 and two four-bar link mechanisms 210. Therefore, the number of drive units 220 is fewer than the number of four-bar link mechanisms 210. In the link mechanism device 200, by reducing the number of drive units 220 to fewer than the number of four-bar link mechanisms 210, the link mechanism device 200 can be configured to be inexpensive, small, and lightweight, and the configuration of the link mechanism device 200 can be simplified.

In the example shown in Figures 1 and 2, the drive unit 220 is connected to the first outer node J11 and moves the first outer node J11 to the side opposite the drive unit 220. This allows the drive unit 220 to drive the first four-joint link mechanism 211 while varying the relative position between the first outer node J11 and the first inner node J12. By driving the first four-joint link mechanism 211, the first four-joint link mechanism 211 can bring the first inner link L13 in the first four-joint link mechanism 211 into contact with the object S.

The drive unit 220 may be a motor mechanism using a stepping motor, a servo motor, or the like. However, as long as the relative position between the first outer node J11 and the first inner node J12 can be changed, there is no limit to the type of drive unit 220. For example, a piston crank mechanism or the like may be used as the drive unit 220. In addition, as long as the relative position between the first outer node J11 and the first inner node J12 can be changed, there is no limit to the configuration for connecting the drive unit 220 and the first outer node J11. For example, a mechanism for converting the direction of force transmission from the drive unit 220 may be provided between the drive unit 220 and the first outer node J11. In this case, the conversion mechanism or the like is included in the drive unit 220.

In the example shown in Figures 1 and 2, the first outer link L11 and the first driving side link L12 are connected by a first outer node J11. The first driving side link L12 and the first inner link L13 are connected by a first inner node J12. The first outer link L11 and the first tip side link L14 are connected by a second outer node J21. The first inner link L13 and the first tip side link L14 are connected by a second inner node J22. The first outer link L11, the second outer link L21 and the second driving side link L22 are connected by a second outer node J21. The first inner link L13, the second driving side link L22 and the second inner link L23 are connected by a second inner node J22. The second outer link L21 and the second tip side link L24 are connected by a third outer node J31. The second inner link L23 and the second tip side link L24 are connected by a third inner node J32. The first tip side link L14 and the second driving side link L22 located at the boundary between the first four-joint link mechanism 211 and the second four-joint link mechanism 212 are the same member. In other words, the first tip side link L14 and the second driving side link L22 can be used interchangeably.

As described above, the lengths of the four links included in the second four-bar link mechanism 212 satisfy A1+B1>C1+D1. On the other hand, there is no particular restriction on the lengths of the four links included in the first four-bar link mechanism 211. Furthermore, when the link mechanism device 200 has three or more four-bar link mechanisms, in order to drive the multiple four-bar link mechanisms 210 so as to follow the shape of the target object S, the four-bar link mechanism connected closer to the tip side than the second four-bar link mechanism 212 is required to satisfy the same conditions as the second four-bar link mechanism 212.

Here, when the link mechanism device 200 has three or more four-bar link mechanisms 210, the conditions for the lengths of the four links required for the four-bar link mechanism 210 located second or later, counting from the drive unit 220 side, are generalized. For example, consider a case where the link mechanism device according to the embodiment has n four-bar link mechanisms 210 connected to each other. n is a natural number of 2 or more. If the length of the nth outer link is An-1, the length of the nth drive side link is Bn-1, the length of the nth inner link is Cn-1, and the length of the nth tip side link is Dn-1, the lengths of the four links in the four-bar link mechanism 210 located second or later, counting from the drive unit 220 side, satisfy (An-1) + (Bn-1) > (Cn-1) + (Dn-1). In this case as well, the force generated by the contact of the four-bar link mechanism 210 on the drive unit 220 side with the object S acts sequentially on the tip side four-bar link mechanism 210. As a result, the link mechanism device 200, which has three or more four-bar link mechanisms 210, can drive n four-bar link mechanisms 210 to follow the shape of the target object S.

In the example shown in Figures 1 and 2, the lengths of the four links included in the second four-bar link mechanism 212 satisfy A1+B1>C1+D1, and also satisfy the respective conditions of A1>B1 and C1>D1. However, as long as the lengths of the four links included in the second four-bar link mechanism 212 satisfy A1+B1>C1+D1, they do not necessarily have to satisfy the conditions of A1>B1 or C1>D1. For example, the lengths of the four links included in the second four-bar link mechanism 212 may satisfy A1+B1>C1+D1, and also satisfy the respective conditions of A1<B1 and C1<D1.

Furthermore, in the link mechanism device 200, each of the four links included in each of the multiple four-bar link mechanisms 210 can be made of a plate-shaped member. By making the links out of plate-shaped members, the four-bar link mechanisms 210 can be made lighter and more flexible than links made out of columnar members. This reduces the weight of the link mechanism device 200 and allows the multiple four-bar link mechanisms 210 to suitably conform to the shape of the object S. Note that the plate-shaped members that make up the links are not limited to being flat, and may be curved.

The material of the links included in each of the multiple four-bar link mechanisms 210 can be selected appropriately according to the application of the link mechanism device 200. The material of the links included in each of the multiple four-bar link mechanisms 210 may be the same or different.

Among the links included in each of the multiple four-bar link mechanisms 210, at least one of the links arranged on the side of the object S, for example the first inner link L13 in the first four-bar link mechanism 211 and the second inner link L23 in the second four-bar link mechanism 212, may be made of a softer material than the other links. By making the link that comes into contact with the object S out of a soft material, the multiple four-bar link mechanisms 210 can be made to suitably conform to the shape of the object S.

Furthermore, among the links included in each of the multiple four-bar link mechanisms 210, the link located at the boundary position between adjacent four-bar link mechanisms 210, for example the first tip link L14 in the first four-bar link mechanism 211, may be made of a soft material. By making the link located at the boundary position between adjacent four-bar link mechanisms 210 out of a soft material, the multiple four-bar link mechanisms 210 can be made to suitably follow the shape of the target object S.

There are no limitations on the configuration of the node, so long as it can connect two adjacent links with variable angles. For example, the node may be a hinge, or an axial member that connects each of the two adjacent links so that they can rotate around a rotation axis. In the example shown in Figures 1 and 2, the two adjacent links are connected by one node, but this is not limiting, and they may be connected by two or more nodes.

In addition, in the link mechanism device 200, the thickness of the plate-like member constituting one of the four links in the four-bar link mechanism 210 can be made 10% or less of the length of the shortest link of the three links connected to that one link. This allows the four-bar link mechanism 210 to be constructed with light weight and excellent flexibility, reducing the weight of the link mechanism device 200 and allowing the multiple four-bar link mechanisms 210 to suitably conform to the shape of the object S. The thickness of the plate-like member constituting one of the four links in the four-bar link mechanism 210 is preferably 8% or less of the length of the shortest link of the three links connected to that one link, and more preferably 6% or less.

In addition, in the link mechanism device 200, the flexibility of the plate-like members constituting the links in the four-bar link mechanism 210 can be made to be 0.08 N or more at a stress of 1.5 mm deflection during three-point bending. This allows the four-bar link mechanism 210 to be made with excellent flexibility, and the multiple four-bar link mechanisms 210 can be made to suitably conform to the shape of the object S. The flexibility of the plate-like members is preferably 0.2 N or more, and more preferably 0.35 N or more at a stress of 1.5 mm deflection during three-point bending.

In addition, in the link mechanism device 200, the plate-like members that make up the links in the multiple four-bar link mechanisms 210 can be made of at least one of resin, carbon fiber, titanium, magnesium, and aluminum. This allows the four-bar link mechanism to be lightweight and highly flexible. This reduces the weight of the link mechanism device 200 and allows the multiple four-bar link mechanisms 210 to suitably follow the shape of the target object S.

(Example of a method for manufacturing the link mechanism device 200)
A method of manufacturing the link mechanism device 200 will be described by taking as an example a case in which hinges are used for the joint members.

(1) First, prepare the hinge and cut out a link to match the width of the hinge (the length of the short side of the hinge).

(2) Next, holes are formed in the links to attach the hinges.

(3) Next, for the links located on the inside (towards the object S) and outside (opposite the object S), hinges are attached to the links so that the hinges are located on the inside. Also, for the links located at the boundary between adjacent four-bar link mechanisms 210, hinges are attached to the links so that the link is sandwiched between the two hinges. Metal, resin, etc. can be used as the material for the hinges. Screws, adhesives, etc. can be used to attach the hinges to the links.

(4) Next, if a tip link is to be provided at the tip of the four-bar link mechanism 210 located at the most tip side (opposite the drive unit 220 side), attach the tip link to the tip of the four-bar link mechanism 210.

(5) Next, connect the drive unit 220 and the first four-bar link mechanism 211.

The above steps allow the link mechanism device 200 to be manufactured.

Comparative Example
(First Comparative Example)
A link mechanism device according to a first comparative example will be described with reference to Fig. 3 and Fig. 4. Fig. 3 is a schematic diagram showing an example of the configuration of a link mechanism device 200X according to the first comparative example. Fig. 4 is a schematic diagram showing an example of the operation of the link mechanism device 200X.

The link mechanism device 200X differs from the link mechanism device 200 according to the first embodiment described above mainly in that the lengths of the four links included in the second four-bar link mechanism 212 satisfy A1 + B1 = C1 + D1. Note that the link mechanism device 200X according to the comparative example is not applied to the embodiment, but for ease of understanding, the same reference numerals are used for components having substantially the same functions as those included in the link mechanism device 200 according to the first embodiment. A1 is the length of the second outer link L21 in the link mechanism device 200X. B1 is the length of the second drive side link L22 in the link mechanism device 200X. C1 is the length of the second inner link L23 in the link mechanism device 200X. D1 is the length of the second tip side link L24 in the link mechanism device 200X. These points are the same in the comparative examples described below.

As shown in Figures 3 and 4, in the link mechanism device 200X, when a force F1 is applied from the drive unit 220 to the first outer node J11, the first drive side link L12 falls toward the object S so as to rotate around the first inner node J12. However, the first inner link L13 does not rotate around the first inner node J12 and does not fall toward the object S, so it does not come into contact with the object S. Therefore, no force is generated in response to the first inner link L13 coming into contact with the object S, and the second four-bar link mechanism 212 is not driven, so it cannot come into contact with the object S. As a result, in the link mechanism device 200X, it is not possible to drive the multiple four-bar link mechanisms 210 to follow the shape of the object S using a number of drive units 220 that is fewer than the number of the multiple four-bar link mechanisms 210.

(Second Comparative Example)
A link mechanism device according to a second comparative example will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is a schematic diagram showing an example of the configuration of a link mechanism device 200Y according to the second comparative example. Fig. 6 is a schematic diagram showing an example of the operation of the link mechanism device 200Y.

The link mechanism device 200Y differs mainly from the link mechanism device 200 according to the first embodiment described above in that the lengths of the four links included in the second four-bar link mechanism 212 satisfy A1+B1<C1+D1.

As shown in Figures 5 and 6, in the link mechanism device 200Y, when a force F1 is applied from the drive unit 220 to the first outer node J11, the first drive side link L12 falls toward the object S so as to rotate around the first inner node J12. However, the first inner link L13 does not rotate around the first inner node J12 and does not fall toward the object S, so it does not come into contact with the object S. Therefore, no force is generated in response to the first inner link L13 coming into contact with the object S, and the second four-bar link mechanism 212 is not driven, so it cannot come into contact with the object S. As a result, in the link mechanism device 200Y, it is not possible to drive the multiple four-bar link mechanisms 210 to follow the shape of the object S using a number of drive units 220 that is fewer than the number of the multiple four-bar link mechanisms 210.

[Second embodiment]
Next, a link mechanism device according to a second embodiment will be described with reference to Figures 7 to 9. Note that the same names and symbols as those in the first embodiment above indicate the same or similar members, and detailed descriptions will be omitted as appropriate. This also applies to the embodiments and modified examples described below.

FIG. 7 is a schematic diagram showing an example of the configuration of the link mechanism device 200A according to the second embodiment. FIG. 8 is a first schematic diagram showing an example of the operation of the link mechanism device 200A. FIG. 9 is a second schematic diagram showing an example of the operation of the link mechanism device 200A.

The link mechanism device 200A differs from the link mechanism device 200 according to the first embodiment mainly in that the multiple four-bar link mechanisms 210 further include a third four-bar link mechanism 213 that is connected to the tip side of the second four-bar link mechanism 212.

In the example shown in Figures 7 to 9, the third four-bar link mechanism 213 includes a third outer link L31 located on the opposite side to the object S when it comes into contact with the object S, a third driving side link L32 located on the driving unit 220 side, a third inner link L33 located on the object S side when it comes into contact with the object S, and a third tip side link L34 located on the opposite side to the driving unit 220 side. If the length of the third outer link L31 is A2, the length of the third driving side link L32 is B2, the length of the third inner link L33 is C2, and the length of the third tip side link L34 is D2, then A2 + B2 > C2 + D2 is satisfied.

In the example shown in Figures 7 to 9, the second outer link L21, the third outer link L31, and the third driving side link L32 are connected by a third outer node J31. The second inner link L23, the third driving side link L32, and the third inner link L33 are connected by a third inner node J32. The third outer link L31 and the third tip side link L34 are connected by a fourth outer node J41. The third inner link L33 and the third tip side link L34 are connected by a fourth inner node J42. The tip link P, the third outer link L31, and the third tip side link L34 are connected by a fourth outer node J41. The second tip side link L24 and the third driving side link L32 located at the boundary between the second four-joint link mechanism 212 and the third four-joint link mechanism 213 are the same member. In other words, the second tip side link L24 and the third drive side link L32 can be used interchangeably.

In the link mechanism device 200A illustrated in Figures 7 to 9, when the first four-bar link mechanism 211 comes into contact with the object S by being driven by the drive unit 220, the second four-bar link mechanism 212 connected to the tip side of the first four-bar link mechanism 211 is driven by forces T21 and T22 generated in response to this contact. The driven second four-bar link mechanism 212 comes into contact with the object S. The third four-bar link mechanism 213 connected to the tip side of the second four-bar link mechanism 212 is driven by forces T31 and T32 generated in response to the second four-bar link mechanism 212 coming into contact with the object S. The driven third four-bar link mechanism 213 comes into contact with the object S.

A more detailed explanation will be given. In the example shown in FIG. 7, a force F1 is applied from the drive unit 220 to the first outer node J11 in a direction toward the tip side. Application of the force F1 causes the first outer node J11 to move toward the tip side. As the first outer node J11 moves, a force T11 that rotates the first inner node J12 around the first inner node J12 acts on the first drive side link L12, causing the first drive side link L12 to fall toward the object S. Furthermore, as the first outer node J11 moves, a force T12 that rotates the first inner link L13 around the first inner node J12 acts on the first inner link L13, causing the first inner link L13 to fall toward the object S. As a result, the first inner link L13 comes into contact with the object S.

When the first inner link L13 comes into contact with the object S, as shown in FIG. 8, a force T21 that rotates the second drive side link L22 around the second inner node J22 acts on the second drive side link L22, causing the second drive side link L22 to fall towards the object S. Furthermore, when the first inner link L13 comes into contact with the object S, a force T22 that rotates the second inner link L23 around the second inner node J22 acts on the second inner link L23, causing the second inner link L23 to fall towards the object S. As a result, the second inner link L23 comes into contact with the object S.

When the second inner link L23 comes into contact with the object S, as shown in FIG. 9, a force T31 that rotates the third drive side link L32 around the third inner node J32 acts on the third drive side link L32, causing the third drive side link L32 to fall towards the object S. Furthermore, when the second inner link L23 comes into contact with the object S, a force T32 that rotates the third drive side link L32 around the third inner node J32 acts on the third inner link L33, causing the third inner link L33 to fall towards the object S. As a result, the third inner link L33 comes into contact with the object S.

When the third inner link L33 comes into contact with the object S, as shown in FIG. 9, a force T41 acts on the third tip link L34 to rotate it about the fourth inner node J42, causing the third tip link L34 to fall towards the object S. Furthermore, when the third inner link L33 comes into contact with the object S, a force T42 acts on the tip link P to rotate it about the fourth outer node J41, causing the tip link P to fall towards the object S. As a result, the tip link P comes into contact with the object S.

In the link mechanism device 200A, the force generated by the four-bar link mechanism 210 located on the drive unit 220 side coming into contact with the object S acts sequentially on the four-bar link mechanism 210 connected to the tip side. This allows the tip side four-bar link mechanism 210 to come into contact with the object S sequentially. The multiple four-bar link mechanisms 210 come into contact with the object S sequentially, starting from the four-bar link mechanism 210 on the drive unit 220 side, and take on a shape that follows the shape of the object S. In this way, in the link mechanism device 200A, the multiple four-bar link mechanisms 210 can be driven to follow the shape of the object S. In other words, in this embodiment, a link mechanism device 200A can be provided that can drive multiple four-bar link mechanisms 210 to follow the shape of the object S using one drive unit 220, which is fewer than the number of three four-bar link mechanisms 210.

Other than the above, the effects of the link mechanism device 200A are the same as those of the link mechanism device according to the first embodiment.

[Modification]
Various modified examples of the link mechanism device according to the embodiment will be described below.

<First Modification>
10 is a schematic diagram showing an example of the configuration of a link mechanism device 200B according to a first modified example. The link mechanism device 200B differs from the above-described embodiment in that the drive unit 220 is connected to the first inner node J12 and moves the first inner node J12 toward the drive unit 220.

With the above configuration, the drive unit 220 can drive the first four-joint link mechanism 211 to vary the relative position between the first outer node J11 and the first inner node J12. In the example shown in FIG. 10, the drive unit 220 applies a force F2 toward the drive unit 220 to the first inner node J12, thereby moving the first inner node J12 toward the drive unit 220. By driving the first four-joint link mechanism 211 in this manner, the first four-joint link mechanism 211 can bring the first inner link L13 in the first four-joint link mechanism 211 into contact with the object S.

The effect of the link mechanism device 200B is the same as that of the link mechanism device according to the first embodiment.

<Second Modification>
11 is a schematic diagram showing an example of the configuration of a link mechanism device 200C according to a second modified example. The link mechanism device 200C differs from the above-described embodiment and modified examples in that the drive unit 220 is connected to both the first outer node J11 and the first inner node J12, and moves the first outer node J11 to the side opposite the drive unit 220 and moves the first inner node J12 to the drive unit 220 side.

The drive unit 220, with the above configuration, can drive the first four-bar link mechanism 211 while varying the relative position between the first outer node J11 and the first inner node J12. This drive allows the first four-bar link mechanism 211 to bring the first inner link L13 in the first four-bar link mechanism 211 into contact with the object S.

The effect of the link mechanism device 200C is the same as that of the link mechanism device according to the first embodiment.

<Third Modification>
12 is a schematic diagram showing an example of the configuration of a link mechanism device 200D according to a third modified example. The link mechanism device 200D differs from the above-described embodiment and modified examples in that it satisfies A1+B1>C1+D1, and also satisfies the conditions A1<B1 and C1<D1. The link mechanism device 200C also provides the same effects as the first embodiment.

<Fourth Modification>
13 is a schematic diagram showing an example of the configuration of a link mechanism device 200E according to a fourth modified example. The link mechanism device 200E differs from the above-described embodiment and modified examples in that the four-bar link mechanisms 210 include six four-bar link mechanisms and the drive unit 220 includes three drive units 220. The number of the drive units 220 is less than the number of the four-bar link mechanisms 210.

In the example shown in FIG. 13, the multiple four-joint link mechanisms 210 include a first four-joint link mechanism 211, a second four-joint link mechanism 212, a third four-joint link mechanism 213, a fourth four-joint link mechanism 214, a fifth four-joint link mechanism 215, and a sixth four-joint link mechanism 216. The drive unit 220 includes a first drive unit 221, a second drive unit 222, and a third drive unit 223.

In the example shown in FIG. 13, the first drive unit 221 is connected to the first four-joint link mechanism 211. The second four-joint link mechanism 212 is connected to the tip side of the first four-joint link mechanism 211. The second drive unit 222 is connected to the tip side of the second four-joint link mechanism 212. The second drive unit 222 is connected to the third four-joint link mechanism 213. The fourth four-joint link mechanism 214 is connected to the tip side of the third four-joint link mechanism 213. The third drive unit 223 is connected to the tip side of the fourth four-joint link mechanism 214. The third drive unit 223 is connected to the fifth four-joint link mechanism 215. The sixth four-joint link mechanism 216 is connected to the tip side of the fifth four-joint link mechanism 215.

The first drive unit 221 drives the first four-bar link mechanism 211. The second four-bar link mechanism 212 is driven by a force generated in response to the first four-bar link mechanism 211 contacting the object S. The position of the second drive unit 222 connected to the tip side of the second four-bar link mechanism 212 is variable in response to the drive of the second four-bar link mechanism 212. The second drive unit 222 drives the third four-bar link mechanism 213. The fourth four-bar link mechanism 214 is driven by a force generated in response to the third four-bar link mechanism 213 contacting the object S. The position of the third drive unit 223 connected to the tip side of the third four-bar link mechanism 213 is variable in response to the drive of the fourth four-bar link mechanism 214. The third drive unit 223 drives the fifth four-bar link mechanism 215. The sixth four-bar link mechanism 216 is driven by a force generated in response to contact of the fifth four-bar link mechanism 215 with the object S.

In the link mechanism device 200E, the six four-bar link mechanisms 210 can be driven to follow the shape of the target object S. From another perspective, in the link mechanism device 200 according to the embodiment, as long as the number of drive units 220 is less than the number of the four-bar link mechanisms 210, the multiple four-bar link mechanisms 210 can be driven to follow the shape of the target object S even when multiple drive units 220 are included. Note that when the link mechanism device according to the embodiment has multiple drive units 220, the side on which the drive unit located farthest from the tip of the link mechanism device according to the embodiment (the first drive unit 221 in the example shown in FIG. 13) is located corresponds to the "drive unit side".

The link mechanism device according to the embodiment may include a rotatable drive unit. By including a rotatable drive unit, the operation of the link mechanism device can be expanded three-dimensionally.

The effects and advantages of the link mechanism device 200D other than those described above are the same as those of the link mechanism device 200 according to the first embodiment.

[Third embodiment]
Next, a robot according to a third embodiment will be described. The robot according to the third embodiment includes a link mechanism device according to at least one of the first embodiment, the second embodiment, the first modified example, the second modified example, the third modified example, and the fourth modified example.

<Configuration example of robot according to third embodiment>
The configuration of the robot according to the third embodiment will be described with reference to Fig. 14 to Fig. 16. Fig. 14 is a schematic perspective view showing an example of the robot 100 according to the third embodiment. Fig. 15 is a schematic side view showing an example of the robot 100. Fig. 16 is a schematic cross-sectional view taken along line XVI-XVI in Fig. 15.

The robot 100 has an exterior member 10 and can be driven by supplied electricity. The robot 100 illustrated in this embodiment is a doll-type communication robot modeled after a baby bear. The robot 100 is manufactured to a size and weight suitable for a user to hold in its arms. Here, the user refers to the user of the robot 100. Representative examples of users include working people living alone, seniors whose children have become independent, and frail elderly people who are the recipients of home medical care. Furthermore, users may include not only users of the robot 100, but also those who simply come into contact with the robot 100, such as the manager of the robot 100.

The exterior member 10 is flexible. The exterior member 10 contains, for example, a soft material that is pleasant to the touch when the user of the robot 100 touches the robot 100. The material of the exterior member 10 can be one that contains organic materials such as urethane foam, rubber, resin, and fiber. The exterior member 10 is preferably composed of an exterior such as a urethane foam material having insulating properties, and a soft cloth material that covers the outer surface of the exterior.

The robot 100, as an example, has a torso 1, a head 2, arms 3, and legs 4. The head 2 has a right eye 2a, a left eye 2b, a mouth 2c, a right cheek 2d, and a left cheek 2e. The arms 3 include a right arm 3a and a left arm 3b. The legs 4 include a right leg 4a and a left leg 4b. The torso 1 corresponds to the robot body. Each of the head 2, arms 3, and legs 4 corresponds to a driver that is connected to the robot body so as to be displaceable relative to the robot body.

In the example shown in Figures 14 to 16, the arms 3 are configured to be displaceable relative to the torso 1. When the robot 100 is held by a user, the right arm 3a and the left arm 3b are displaced and come into contact with the user's neck, torso, etc. as if hugging the user. This action makes the user feel a sense of closeness to the robot 100, promoting interaction between the user and the robot 100. Note that interaction with the user refers to actions in which the user and the robot 100 come into contact with each other (actions of contact), such as stroking, tapping (touching), and hugging (embracing each other).

The torso 1, head 2, arms 3, and legs 4 are all covered with an exterior member 10. The exterior member on the torso 1 and the exterior member on the arms 3 are integrated, and the exterior members on the head 2 and legs 4 are separate from the exterior members on the torso 1 and arms 3. However, this is not limited to the above configuration, and for example, only the parts of the robot 100 that are likely to be touched by the user may be covered with the exterior member 10. Furthermore, at least one of the exterior members 10 on each of the torso 1, head 2, arms 3, and legs 4 may be separate from the other exterior members. Furthermore, the parts of the head 2, arms 3, and legs 4 that do not displace may not include components such as sensors inside, and may be composed only of the exterior member 10.

The robot 100 has a camera 11, a tactile sensor 12, a control unit 13, a vital sensor 14, a battery 15, a first capacitance sensor 21, and a second capacitance sensor 31 inside the exterior member 10. The robot 100 also has a camera 11, a tactile sensor 12, a control unit 13, a vital sensor 14, and a battery 15 inside the exterior member 10 in the torso 1. The robot 100 also has a first capacitance sensor 21 inside the exterior member 10 in the head 2, and a second capacitance sensor 31 inside the exterior member 10 in the arm 3.

The robot 100 also has a display 24, a speaker 25, and a light 26 on the inside of the exterior member 10 in the head 2. The robot 100 also has a display 24 on the inside of the exterior member 10 in the right eye 2a and left eye 2b. In addition, the robot 100 has a speaker 25 on the inside of the exterior member 10 in the mouth 2c, and a light 26 on the inside of the exterior member 10 in the right cheek 2d and left cheek 2e.

16, the robot 100 has a torso frame 16, a torso mounting base 17, a right arm drive unit 220a, and a left arm drive unit 220b inside the exterior member 10 in the torso 1. The robot 100 also has a head frame 22 and a head mounting base 23 inside the exterior member 10 in the head 2. The robot 100 also has a plurality of right arm four-joint link mechanisms 210a inside the exterior member 10 in the right arm 3a, and a plurality of right arm four-joint link mechanisms 210a inside the exterior member 10 in the left arm 3b. In addition, the robot 100 has a right leg frame 42a inside the exterior member 10 in the right leg 4a, and a left leg frame 42b inside the exterior member 10 in the left leg 4b. The right arm drive unit 220a and the multiple right arm four-joint link mechanisms 210a constitute a right arm link mechanism device 200a. The left arm drive unit 220b and the multiple left arm four-joint link mechanisms 210b constitute a left arm link mechanism device 200b.

The torso frame 16, head frame 22, right leg frame 42a, and left leg frame 42b are each structures formed by combining multiple columnar members. The torso support platform 17 and head support platform 23 are plate-like members having a support surface. The torso support platform 17 is fixed to the torso frame 16, and the head support platform 23 is fixed to the head frame 22. The torso frame 16, head frame 22, right leg frame 42a, and left leg frame 42b may be formed in a box shape including multiple plate-like members.

The multiple right arm four-joint link mechanisms 210a are connected to the torso frame 16 via the right arm drive unit 220a. The right arm four-joint link mechanisms 210a are driven by the right arm drive unit 220a and can be displaced relative to the torso frame 16. As the right arm four-joint link mechanisms 210a are displaced, the right arm 3a is displaced relative to the torso 1. The right arm drive unit 220a preferably has, for example, a reducer that increases the output torque of the right arm drive unit 220a.

The multiple left arm four-joint link mechanisms 210b are connected to the torso frame 16 via the left arm drive unit 220b. The left arm four-joint link mechanisms 210b are driven by the left arm drive unit 220b and can be displaced relative to the torso frame 16. Displacement of the left arm four-joint link mechanisms 210b displaces the left arm 3b relative to the torso 1. The left arm drive unit 220b preferably has, for example, a reducer that increases the output torque of the left arm drive unit 220b.

The right arm link mechanism device 200a can drive the multiple right arm four-joint link mechanisms 210a to follow the shape of the object S using a number of right arm drivers 220a fewer than the number of the multiple right arm four-joint link mechanisms 210a. The left arm link mechanism device 200b can drive the multiple left arm four-joint link mechanisms 210b to follow the shape of the object S using a number of left arm drivers 220b fewer than the number of the multiple left arm four-joint link mechanisms 210b. This makes it possible to configure the right arm link mechanism device 200a and the left arm link mechanism device 200b to be inexpensive, small, and lightweight, and to simplify the configuration of the right arm link mechanism device 200a and the left arm link mechanism device 200b. Furthermore, by having the right arm link mechanism device 200a and the left arm link mechanism device 200b in the arm 3, the robot 100 can be configured to be inexpensive, small, and lightweight, and the configuration of the robot 100 can be simplified.

In the example shown in FIG. 14 to FIG. 16, the object S that the right arm link mechanism device 200a and the left arm link mechanism device 200b come into contact with is the user of the robot 100 who is holding the robot 100. For example, when the user holds the robot 100 and brings the robot 100 into contact with the user's torso, the multiple right arm four-joint link mechanisms 210a and the multiple left arm four-joint link mechanisms 210b are driven to imitate the shape of the user's torso, which is the object S. As a result, the multiple right arm four-joint link mechanisms 210a and the multiple left arm four-joint link mechanisms 210b are wrapped around the user's torso, and the right arm 3a and the left arm 3b of the robot 100 are wrapped around the user's torso. As the right arm 3a and the left arm 3b are wrapped around the torso, the user feels a sense of closeness to the robot 100. This can promote communication between the user and the robot 100.

The head frame 22 is connected to the torso frame 16 via a head connection mechanism 27, and is driven by a head servomotor 35c, allowing it to be displaced relative to the torso frame 16. As the head frame 22 is displaced, the head 2 is displaced relative to the torso 1. The head connection mechanism 27 preferably has, for example, a reducer that increases the output torque of the head servomotor 35c.

In the example shown in Figures 14 to 16, the head frame 22 has a neck frame F1c and a face frame F2c. The torso frame 16, the neck frame F1c, and the face frame F2c are each connected to each other via a connecting mechanism.

Head servo motor 35c is a general term for multiple servo motors. For example, the head servo motor 35c has a neck servo motor M1c and a face servo motor M2c. The neck servo motor M1c rotates the neck frame F1c around a rotation axis perpendicular to the torso frame 16. The face servo motor M2c rotates the face frame F2c around a rotation axis perpendicular to the rotation axis of the neck frame F1c.

As a result of the head 2 having two-axis joints, the robot 100 can perform movements with a higher level of realism.

The right leg frame 42a is connected to the torso frame 16 via a right leg connecting mechanism 44a, and has a right leg wheel 41a on the bottom side. To stabilize the posture of the robot 100, it is preferable that the robot 100 has two right leg wheels 41a in the front-to-rear direction of the right leg frame 42a. The right leg wheel 41a is driven by the right leg servo motor 35d and can rotate around a rotation axis perpendicular to the front-to-rear direction of the right leg frame 42a. The rotation of the right leg wheel 41a enables the robot 100 to run. The right leg connecting mechanism 44a preferably has a reducer that increases the output torque of the right leg servo motor 35d, for example.

The left leg frame 42b is connected to the torso frame 16 via a left leg connecting mechanism 44b, and has a left leg wheel 41b on the bottom side. To stabilize the posture of the robot 100, it is preferable that the robot 100 has two left leg wheels 41b in the front-to-rear direction of the left leg frame 42b. The left leg wheel 41b is driven by the left leg servo motor 35e and can rotate around an axis of rotation perpendicular to the front-to-rear direction of the left leg frame 42b. The rotation of the left leg wheel 41b enables the robot 100 to run. The left leg connecting mechanism 44b preferably has a reducer that increases the output torque of the left leg servo motor 35e, for example.

In the example shown in Figures 14 to 16, the robot 100 moves forward or backward by simultaneously rotating the right leg wheel 41a and the left leg wheel 41b forward or backward. The robot 100 turns right or left by braking either the right leg wheel 41a or the left leg wheel 41b and rotating the other forward or backward.

In this way, the legs 4 allow the robot 100 to perform movements with a higher level of realism.

The camera 11 is fixed to the torso frame 16. The tactile sensor 12, the control unit 13, the vital sensor 14, and the battery 15 are fixed to the torso mounting base 17. The control unit 13 and the battery 15 are fixed to the torso mounting base 17 on the side opposite to the side to which the tactile sensor 12 and the vital sensor 14 are fixed. The arrangement of the control unit 13 and the battery 15 here is based on the available space on the torso mounting base 17 and is not necessarily limited to the above. However, if the battery 15 is fixed to the side opposite to the side to which the tactile sensor 12 and the vital sensor 14 are fixed on the torso mounting base 17, the center of gravity of the robot 100 will be lowered because the battery 15 is heavier than the other components. A low center of gravity of the robot 100 is preferable because at least one of the position and posture of the robot 100 is stabilized and at least one of charging and replacing the battery 15 is easier to perform.

The first capacitance sensor 21 is fixed to the head rest 23, and the second capacitance sensor 31 is fixed to the right arm rest 33. The display 24 has a right eye display 24a and a left eye display 24b. The right eye display 24a, the left eye display 24b and the speaker 25 are fixed to the head frame 22. The light 26 has a right cheek light 26a and a left cheek light 26b. The right cheek light 26a and the left cheek light 26b are fixed to the head frame 22.

The camera 11, tactile sensor 12, control unit 13, vital sensor 14, battery 15, first capacitance sensor 21, second capacitance sensor 31, etc. can be fixed with screws or adhesive members, etc. The right eye display 24a, left eye display 24b, speaker 25, right cheek light 26a, left cheek light 26b, etc. can also be fixed with screws or adhesive members, etc.

There are no particular restrictions on the materials used for the torso frame 16, torso mounting base 17, head frame 22, and head mounting base 23, and resin or metal materials can be used. However, from the perspective of ensuring strength when driven, it is preferable to use a metal material such as aluminum for the torso frame 16. On the other hand, if strength can be ensured, it is preferable to use a resin material for each of these parts in order to reduce the weight of the robot 100. There are no particular restrictions on the materials used for the torso mounting base 17, head frame 22, and head mounting base 23, and resin or metal materials can be used, but from the perspective of reducing the weight of the robot 100, it is preferable to use a resin material.

The control unit 13 is communicatively connected to each of the camera 11, tactile sensor 12, vital sensor 14, first capacitance sensor 21, second capacitance sensor 31, and head servo motor 35c, either by wire or wirelessly. Furthermore, the control unit 13 is communicatively connected to each of the right eye display 24a, left eye display 24b, speaker 25, right cheek light 26a, and left cheek light 26b, either by wire or wirelessly.

The camera 11 is an image sensor that outputs captured images of the robot 100's surroundings to the control unit 13. The camera 11 includes a lens and an imaging element that captures an image through the lens. The imaging element can be a CCD (Charge Coupled Device) or a CMOS (Complementary Metal-Oxide Semiconductor), etc. The captured image can be either a still image or a video.

Furthermore, it is preferable that the camera 11 is configured by a TOF (Time Of Flight) camera that outputs a distance image of the periphery of the robot 100 to the control unit 13. Therefore, the captured image output from the camera 11 may include a three-dimensional captured image (distance image) in addition to or instead of a two-dimensional captured image. The captured image is used to detect the presence or approach of a user, detect the distance from the robot 100 to the user, authenticate the user, or estimate the user's emotions or behavior, etc. The captured image is an example of a captured image showing a user. Furthermore, the robot 100 may be equipped with a human presence sensor such as an ultrasonic sensor, an infrared sensor, a millimeter wave radar, or a LiDAR (light detection and ranging) in addition to the camera 11.

The tactile sensor 12 is a sensor element that detects information sensed by the sense of touch in the human hand, etc., converts it into a tactile signal, which is an electrical signal, and outputs it to the control unit 13. For example, the tactile sensor 12 converts information about pressure or vibration caused by a user touching the robot 100 into a tactile signal using a piezoelectric element, and outputs it to the control unit 13. The tactile signal output from the tactile sensor 12 is used to detect the user's contact or presence with the robot 100.

The vital sensor 14 is an example of an electromagnetic wave sensor that uses electromagnetic waves to obtain the user's biometric information.

The first capacitance sensor 21 and the second capacitance sensor 31 are sensor elements that detect when a user has come into contact with or near the robot 100 based on a change in capacitance and output a capacitance signal to the control unit 13. The first capacitance sensor 21 is preferably a rigid sensor that does not have flexibility in terms of stabilizing the exterior member 10. Since the arm 3 is a part that is easily touched by the user, the second capacitance sensor 31 is preferably a flexible sensor that includes conductive thread or the like in terms of improving the feel. The capacitance signals output from the first capacitance sensor 21 and the second capacitance sensor 31 are used to detect the proximity or presence of a user to the robot 100.

The right eye display 24a and the left eye display 24b are display modules that display characters or images such as letters, numbers, and symbols in response to commands from the control unit 13. The right eye display 24a and the left eye display 24b are, for example, liquid crystal display modules. The characters or images displayed on the right eye display 24a and the left eye display 24b are used to express the emotions of the robot 100. For example, the robot 100 can implicitly induce contact with a user by displaying a "laughing" image on the right eye display 24a and the left eye display 24b to a user who is sitting with happy emotions, thereby empathizing with the happiness.

The speaker 25 is a speaker unit that amplifies the audio signal from the control unit 13 and outputs the sound. The sound output from the speaker 25 is the words or cries of the robot 100, and is used to express the emotions of the robot 100. For example, the robot 100 can perform an action that induces contact with the user by outputting a "(worried) voice" sound from the speaker 25 to a user who is doing housework and feeling sad.

The right cheek light 26a and the left cheek light 26b are light modules that blink or change color in response to an on/off signal from the control unit 13. The right cheek light 26a and the left cheek light 26b are, for example, configured with an LED (Light Emitting Diode) light module. The blinking or color change of the right cheek light 26a and the left cheek light 26b is used to express emotions of the robot 100. For example, the robot 100 can express sympathy to a user who is sitting with a sad emotion by making the right cheek light 26a and the left cheek light 26b blink blue, thereby enabling the robot 100 to perform an action that induces contact with the user.

The battery 15 is a power source that supplies power to the camera 11, tactile sensor 12, control unit 13, vital sensor 14, first capacitance sensor 21, second capacitance sensor 31, right arm drive unit 220a, and left arm drive unit 220b. The battery 15 also supplies power to the head servo motor 35c, right leg servo motor 35d, and left leg servo motor 35e. The battery 15 also supplies power to the right eye display 24a, left eye display 24b, speaker 25, right cheek light 26a, and left cheek light 26b. Various secondary batteries such as lithium ion batteries and lithium polymer batteries can be used for the battery 15.

Note that the various sensors such as the first capacitance sensor 21 and the second capacitance sensor 31 in the robot 100 are not essential components. The robot 100 only needs to have at least the camera 11, the vital sensor 14, and the tactile sensor 12. The installation positions of these sensors can also be changed as appropriate. Furthermore, the various sensors such as the camera 11, the vital sensor 14, and the tactile sensor 12 may be placed outside the robot 100 and transmit necessary information to the robot 100 or an external device via wireless communication. For example, a PC (Personal Computer) is an example of an external device.

Furthermore, the robot 100 does not necessarily have to have the control unit 13 inside the exterior member 10, and the control unit 13 can also wirelessly communicate with each device from outside the exterior member 10. The battery 15 can also supply power to each component from outside the exterior member 10.

In this embodiment, a configuration in which the head 2, arms 3, and legs 4 are displaceable is exemplified, but this is not limited thereto, and at least one of the head 2, arms 3, and legs 4 may be displaceable. It is preferable that the arms 3 are connectable to an end effector such as a hand. Furthermore, the legs 4 are configured using a wheel system, but can also be configured using a crawler system or leg system, etc.

The configuration and shape of the robot 100 are not limited to those exemplified in Figs. 14 to 16, and can be modified as appropriate according to the user's preferences and the manner in which the robot 100 is used. For example, the robot 100 may be in the form of a robot arm such as an industrial robot, or in the form of a humanoid, rather than a form imitating a baby bear. The robot 100 may also be in the form of a mobile device such as a drone or vehicle that has at least one of an arm, a display, a speaker, and a light, etc.

Although the preferred embodiment has been described in detail above, the present invention is not limited to the above-described embodiment, and various modifications and substitutions can be made to the above-described embodiment without departing from the scope of the claims.

In addition, all ordinal numbers, quantities, and other numbers used in the description of the above embodiments are merely examples given to specifically explain the technology of the present invention, and the present invention is not limited to the exemplified numbers. In addition, the connections between the components are merely examples given to specifically explain the technology of the present invention, and the connections that realize the functions of the present invention are not limited to these.

The link mechanism device according to the embodiment can be suitably used in robots, transport mechanisms, transport devices, etc. The link mechanism device according to the embodiment can drive multiple four-bar link mechanisms to follow the shape of an object using a number of drive units that is fewer than the number of multiple four-bar link mechanisms, so that the robot, transport mechanism, transport device, etc. can be configured to be inexpensive, small, and lightweight, and the configuration of the robot, transport mechanism, transport device, etc. can be simplified.

The robot according to the embodiment is particularly suitable for use in promoting oxytocin secretion and providing healing (sense of security or self-affirmation) to working people living alone, seniors whose children have become independent, frail elderly people who are the recipients of in-home medical care, etc. However, the robot is not limited to this use, and can also be used as an industrial robot, etc.

Aspects of the present disclosure are, for example, as follows.
<1> A device having a plurality of four-joint link mechanisms connected to each other and a drive unit that drives the four-joint link mechanisms, the plurality of four-joint link mechanisms including a first four-joint link mechanism connected to the drive unit and a second four-joint link mechanism connected to the first four-joint link mechanism, the first four-joint link mechanism including a first outer link located on the side opposite to the object when in contact with the object, a first drive-side link located on the drive unit side, a first inner link located on the object when in contact with the object, and a first tip-side link located on the side opposite to the drive unit, the second four-joint link mechanism including a second outer link located on the side opposite to the object when in contact with the object, and a second drive-side link located on the drive unit side. a first outer link, a second inner link that is positioned on the object side when it comes into contact with the object, and a second tip side link that is positioned opposite the driving unit side, wherein the driving unit is connected to at least one of a first outer node portion that connects an end of the first outer link and an end of the first driving side link and a first inner node portion that connects an end of the first driving side link and an end of the first inner link, and drives the first four-bar link mechanism to vary the relative position of the first outer node portion and the first inner node portion, wherein A1 is a length of the second outer link, B1 is a length of the second driving side link, C1 is a length of the second inner link, and D1 is a length of the second tip side link, such that A1 + B1 > C1 + D1 is satisfied.
<2> The link mechanism device according to <1>, wherein the drive unit is connected to the first outer node unit and moves the first outer node unit to an opposite side to the drive unit unit.
<3> The link mechanism device according to <1>, wherein the drive portion is connected to the first inner node portion and moves the first inner node portion toward the drive portion.
<4> The link mechanism device according to any one of <1> to <3>, wherein each of the four links included in each of the plurality of four-bar link mechanisms is formed of a plate-shaped member.
<5> The link mechanism device according to <4>, wherein a thickness of the plate-like member constituting one of the four links is 10% or less of a length of the shortest link among three links connected to the one link.
<6> The link mechanism device according to <4> or <5>, wherein the flexibility of the plate-like member is 0.08 N or more in terms of a stress at a deflection of 1.5 mm when bent at three points.
<7> The link mechanism device according to any one of <4> to <6>, wherein the plate-like member is made of at least one of resin, carbon fiber, titanium, magnesium, and aluminum.
<8> The link mechanism device according to any one of <1> to <7>, wherein the multiple four-bar link mechanisms include a third four-bar link mechanism connected to the second four-bar link mechanism, the third four-bar link mechanism including a third outer link located on the opposite side to the object when it comes into contact with the object, a third driving side link located on the driving unit side, a third inner link located on the object side when it comes into contact with the object, and a third tip side link located on the opposite side to the driving unit, wherein A2 + B2 > C2 + D2 is satisfied, where A2 is a length of the third outer link, B2 is a length of the third driving side link, C2 is a length of the third inner link, and D2 is a length of the third tip side link.
<9> A robot having the link mechanism device according to any one of <1> to <8>.

This application claims priority based on Japanese Patent Application No. 2023-169704 filed with the Japan Patent Office on September 29, 2023, and includes the entire contents of this Japanese patent application.

LIST OF SYMBOLS 1 Torso 2 Head 2a Right eye 2b Left eye 2c Mouth 2d Right cheek 2e Left cheek 3 Arm 3a Right arm 3b Left arm 4 Leg 4a Right leg 4b Left leg 10 Exterior member 11 Camera 12 Touch sensor 13 Control unit 14 Vital sensor 15 Battery 16 Torso frame 17 Torso placement platform 21 First capacitance sensor 22 Head frame 23 Head placement platform 24 Display 24a Right eye display 24b Left eye display 25 Speaker 26 Light 26a Right cheek light 26b Left cheek light 27 Head connection mechanism 31 Second capacitance sensor 35c Head servo motor 35d Right leg servo motor 35e Left leg servo motor 41a Right leg wheel 41b Left leg wheel 42a Right leg frame 42b Left leg frame 44a Right leg connecting mechanism 44b Left leg connecting mechanism 100 Robot 200, 200A, 200B, 200C, 200D, 200E Link mechanism device 200a Right arm link mechanism device 200b Left arm link mechanism device 210 Four-joint link mechanism 211 First four-joint link mechanism 212 Second four-joint link mechanism 213 Third four-joint link mechanism 214 Fourth four-joint link mechanism 215 Fifth four-joint link mechanism 216 Sixth four-joint link mechanism 210a Right arm four-joint link mechanism 210b Left arm four-joint link mechanism 220 Drive unit 220a Right arm drive unit 220b Left arm drive unit 221 First drive unit 222 Second drive unit 223 Third drive unit F1c Neck frame F2c Face frame M1c Neck servo motor M2c Face servo motors F1, F2, F3, F4, T11, T12, T21, T22, T31, T32 Force J11 First outer node J12 First inner node J21 Second outer node J22 Second inner node J31 Third outer node J32 Third inner node J41 Fourth outer node J42 Fourth inner node L11 First outer link L12 First driving side link L13 First inner link L14 First tip side link L21 Second outer link L22 Second driving side link L23 Second inner link L24 Second tip side link L31 Third outer link L32 Third driving side link L33 Third inner link L34 Third tip side link P Tip link S Object

Claims (9)

A plurality of four-bar link mechanisms connected to each other;
A drive unit that drives the four-bar link mechanism,
the plurality of four-bar link mechanisms include a first four-bar link mechanism connected to the drive unit and a second four-bar link mechanism coupled to the first four-bar link mechanism,
The first four-bar link mechanism includes:
a first outer link positioned opposite to the object side when the first outer link contacts the object;
A first driving side link located on the driving unit side;
a first inner link positioned on the object side when the first inner link contacts the object;
a first tip side link located on the opposite side to the drive unit side,
The second four-bar link mechanism includes:
a second outer link positioned on an opposite side to the object when the second outer link contacts the object;
A second driving side link located on the driving unit side;
a second inner link positioned on the object side when the second inner link contacts the object;
a second tip side link located on the opposite side to the drive unit side,
the drive section is connected to at least one of a first outer node section that connects an end of the first outer link and an end of the first driving side link and a first inner node section that connects an end of the first driving side link and an end of the first inner link, and drives the first four-bar link mechanism to vary the relative position of the first outer node section and the first inner node section;
A link mechanism device in which, when the length of the second outer link is A1, the length of the second driving side link is B1, the length of the second inner link is C1, and the length of the second tip side link is D1, A1 + B1 > C1 + D1 is satisfied. The link mechanism device according to claim 1, wherein the drive unit is connected to the first outer node and moves the first outer node in a direction opposite to the drive unit. The link mechanism device according to claim 1, wherein the drive unit is connected to the first inner node and moves the first inner node toward the drive unit. The link mechanism device according to claim 1, wherein each of the four links included in each of the four-bar link mechanisms is made of a plate-shaped member. The link mechanism device according to claim 4, wherein the thickness of the plate member constituting one of the four links is 10% or less of the length of the shortest link among the three links connected to the one link. The link mechanism device according to claim 4, wherein the flexibility of the plate-like member is 0.08 N or more at a stress of 1.5 mm when bent at three points. The link mechanism device according to claim 4, wherein the plate-like member is made of at least one of resin, carbon fiber, titanium, magnesium, and aluminum. the plurality of four-bar linkages includes a third four-bar linkage connected to the second four-bar linkage;
The third four-bar link mechanism comprises:
a third outer link positioned on an opposite side to the object when the third outer link contacts the object;
a third driving side link located on the driving unit side;
a third inner link positioned on the object side when the third inner link contacts the object;
a third tip side link located on the opposite side to the drive unit side,
2. The link mechanism device according to claim 1, wherein when the length of the third outer link is A2, the length of the third driving side link is B2, the length of the third inner link is C2, and the length of the third tip side link is D2, A2 + B2 > C2 + D2 is satisfied. A robot having a link mechanism device according to any one of claims 1 to 8.