Link mechanism device and robot

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

[0001] The present disclosure relates to a link mechanism device and a robot.

[0002] A link mechanism device having a plurality of four-bar link mechanisms connected together has been known. Patent Document 1 discloses a configuration in which the lengths of the links included in the four-bar link mechanism are specified.

[0003] Patent No. 6948647

[0004] However, in a conventional link mechanism device, in order to drive a plurality of 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 may become expensive, and the size and weight of the link mechanism device may increase, and the configuration of the link mechanism device may become complicated.

[0005] 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 multiple four-bar link mechanisms.

[0006] A link mechanism device according to one aspect of the present disclosure includes a plurality of four-bar link mechanisms connected to each other and a drive unit that drives the four-bar link mechanisms, wherein 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 connected to the first four-bar link mechanism, wherein the first four-bar link mechanism includes 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 side when in contact with the object, and a first tip-side link located on the side opposite to the drive unit side, and the second four-bar link mechanism includes a second outer link located on the side opposite to the object when in contact with the object, the first four-bar link mechanism includes a second driving side link located on the driving unit side, a second inner link that is located on the object side when it comes into contact with the object, and a second tip side link located on the opposite side from 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 to an end of the first driving side link and a first inner node portion that connects the end of the first driving side link to an end of the first inner link, and drives the first four-bar link mechanism so that the relative position of the first outer node portion and the first inner node portion is variable, and where 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, the relationship A1 + B1 > C1 + D1 is satisfied.

[0007] 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 multiple four-bar link mechanisms.

[0008] 16 is a schematic diagram showing a configuration example of a link mechanism device according to the first embodiment. FIG. 16 is a schematic diagram showing an operation example of the link mechanism device according to the first embodiment. FIG. 16 is a schematic diagram showing a configuration example of a link mechanism device according to a first comparative example. FIG. 16 is a schematic diagram showing an operation example of the link mechanism device according to the first comparative example. FIG. 16 is a schematic diagram showing an operation example of the link mechanism device according to a second comparative example. FIG. 16 is a schematic diagram showing an operation example of the link mechanism device according to the second comparative example. FIG. 16 is a schematic diagram showing an operation example of the link mechanism device according to the second embodiment. FIG. 16 is a first schematic diagram showing an operation example of the link mechanism device according to the second embodiment. FIG. 16 is a second schematic diagram showing an operation example of the link mechanism device according to the second embodiment. FIG. 16 is a schematic diagram showing an example of the configuration of a link mechanism device according to a first modified example. FIG. 16 is a schematic diagram showing an example of the configuration of a link mechanism device according to a second modified example. FIG. 16 is a schematic diagram showing an example of the configuration of a link mechanism device according to a third modified example. FIG. 16 is a schematic diagram showing an example of the configuration of a link mechanism device according to a fourth modified example. FIG. 16 is a schematic front view showing an example of a robot according to the third embodiment. FIG. 16 is a schematic side view showing an example of a robot according to the third embodiment. FIG. 16 is a schematic cross-sectional view taken along line XVI-XVI in FIG.

[0009] Hereinafter, embodiments 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 duplicated descriptions will be omitted as appropriate.

[0010] The embodiments described below exemplify a link mechanism device and a robot for embodying the technical ideas of the present disclosure, and the present disclosure is not limited to the embodiments described below. Unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described below are intended for illustration purposes only and are not intended to limit the scope of the present disclosure. Furthermore, the sizes and positional relationships of components shown in the drawings may be exaggerated for clarity.

[0011] [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 Figures 1 and 2. Figure 1 is a schematic diagram showing an example of the configuration of a link mechanism device 200 according to the first embodiment. Figure 2 is a schematic diagram showing an example of the operation of the link mechanism device 200.

[0012] The link mechanism device 200 has a plurality of four-bar link mechanisms 210 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 includes a first four-bar link mechanism 211 connected to the drive unit 220 and a second four-bar link mechanism 212 connected to the first four-bar link mechanism 211.

[0013] The first four-bar link mechanism 211 includes a first outer link L11 located on the side opposite the object S when it comes into contact with the object S, and a first drive-side link L12 located on the drive unit 220 side. The first four-bar link mechanism 211 also includes a first inner link L13 located on the side of the object S when it comes into contact with the object S, and a first tip-side link L14 located on the side opposite the drive unit 220 side.

[0014] The second four-bar link mechanism 212 includes a second outer link L21 located on the opposite side to the object S when it comes into contact with the object S, and a second drive-side link L22 located on the drive unit 220 side. The second four-bar link mechanism 212 also includes a second inner link L23 located on the object S side when it comes into contact with the object S, and a second tip-side link L24 located on the opposite side to the drive unit 220 side.

[0015] The drive unit 220 can be connected to at least one of the first outer node J11 connecting an end of the first outer link L11 to an end of the first driving link L12 and the first inner node J12 connecting an end of the first driving link L12 to an end of the first inner link L13. The drive unit 220 drives the first four-bar link mechanism 211 to vary the relative positions of the first outer node J11 and the first inner node J12.

[0016] Let A1 be the length of the second outer link L21, B1 be the length of the second driving side link L22, C1 be the length of the second inner link L23, and D1 be the length of the second tip side link L24. In this specification, the term "link length" refers to the length measured from one node of the link to the other node when the link and another link are connected to form a node. If the link is non-linear, 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.

[0017] 1 and 2 , when the first four-bar link mechanism 211 is driven by the drive unit 220 and comes into contact with the object S, forces T21 and T22 generated in response to this contact drive the second four-bar link mechanism 212, which is connected closer to the tip side than the first four-bar link mechanism 211. 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 to the drive unit 220 side.

[0018] This will be explained in more detail. 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 distal end. The application of the force F1 causes the first outer node J11 to move toward the distal end. As the first outer node J11 moves toward the distal end, a force T11 acts on the first drive-side link L12, causing it to rotate about the first inner node J12, and the first drive-side link L12 tilts toward the object S. Furthermore, as the first outer node J11 moves toward the distal end, a force T12 acts on the first inner link L13, causing it to rotate about the first inner node J12, and the first inner link L13 tilts toward the object S. As a result, the first inner link L13 comes into contact with the object S.

[0019] When the first inner link L13 comes into contact with the object S, as shown in Figure 2, a force T21 acts on the second driving-side link L22 to rotate it about the second inner node J22, causing the second driving-side link L22 to tilt toward 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 about the second inner node J22, causing the second inner link L23 to tilt toward the object S. As a result, the second inner link L23 comes into contact with the object S.

[0020] In the link mechanism device 200, a force generated when the four-bar link mechanism 210 located on the drive unit 220 side comes into contact with the object S sequentially acts on the four-bar link mechanisms 210 connected to the tip side. This allows the tip-side four-bar link mechanisms 210 to come into contact with the object S sequentially. As the four-bar link mechanisms 210 sequentially come into contact with the object S from the drive unit 220 side to the tip side, the multiple four-bar link mechanisms 210 assume a shape that follows the shape of the object S. In this manner, the link mechanism device 200 can drive the multiple four-bar link mechanisms 210 so that they follow the shape of the object S. In other words, this embodiment can provide a link mechanism device 200 that can drive the multiple four-bar link mechanisms 210 so that they 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. From another perspective, the link mechanism device 200 forms a so-called underactuated arm and can drive the multiple four-bar link mechanisms 210 so that they follow the shape of the object S.

[0021] 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.

[0022] Furthermore, the link mechanism device 200 can drive the four-bar link mechanisms 210 using fewer drive units 220 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.

[0023] 1 and 2 , the drive unit 220 is connected to the first outer node J11 and moves the first outer node J11 toward the opposite side from the drive unit 220. This allows the drive unit 220 to drive the first four-bar link mechanism 211 while varying the relative position of the first outer node J11 and the first inner node J12. By driving the first four-bar link mechanism 211, the first four-bar link mechanism 211 can bring the first inner link L13 of the first four-bar link mechanism 211 into contact with the object S.

[0024] The drive unit 220 can 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 limitation on the type of drive unit 220. For example, a piston-crank mechanism or the like can be used as the drive unit 220. Furthermore, as long as the relative position between the first outer node J11 and the first inner node J12 can be changed, there is no limitation on 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.

[0025] 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, which are located at the boundary between the first four-bar link mechanism 211 and the second four-bar 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 interchangeable.

[0026] 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 limit to 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 than the second four-bar link mechanism 212 is required to satisfy the same conditions as the second four-bar link mechanism 212.

[0027] Here, when the link mechanism device 200 includes three or more four-bar link mechanisms 210, the conditions for the lengths of the four links required for the four-bar link mechanisms 210 positioned second or later, counting from the drive unit 220, 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 greater than or equal to 2. 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, then the lengths of the four links in the four-bar link mechanism 210 positioned second or later, counting from the drive unit 220, satisfy (An-1) + (Bn-1) > (Cn-1) + (Dn-1). In this case, too, the force generated when the four-bar link mechanism 210 on the drive unit 220 side comes into contact with the object S acts sequentially on the tip-side four-bar link mechanism 210. As a result, the link mechanism device 200 having three or more four-bar link mechanisms 210 can drive the n four-bar link mechanisms 210 so as to follow the shape of the object S.

[0028] 1 and 2, the lengths of the four links included in the second four-bar linkage 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 linkage 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 linkage 212 may satisfy A1+B1>C1+D1, and also satisfy the respective conditions of A1<B1 and C1<D1.

[0029] 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 configured using a plate-like member. By configuring the links using plate-like members, the four-bar link mechanism 210 can be configured to be lightweight and have excellent flexibility compared to when the links are configured using columnar members. 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 object S. Note that the plate-like members configuring the links are not limited to being flat, and may also be curved.

[0030] The material of the links included in each of the multiple four-bar link mechanisms 210 can be selected appropriately depending on the application of the link mechanism device 200. The materials of the links included in each of the multiple four-bar link mechanisms 210 may be the same or different.

[0031] Of the links included in each of the multiple four-bar link mechanisms 210, at least one of the links arranged on the object S side, 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 follow the shape of the object S.

[0032] Furthermore, among the links included in each of the multiple four-bar link mechanisms 210, a link located at the boundary between adjacent four-bar link mechanisms 210, for example, the first tip-side 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 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 object S.

[0033] There are no limitations on the configuration of the node as long as it can connect two adjacent links so that the angle can be changed. For example, the node may be a hinge, or a shaft-shaped 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 the two adjacent links may be connected by two or more nodes.

[0034] Furthermore, in the link mechanism device 200, the thickness of the plate-like member that constitutes one of the four links in the four-bar link mechanism 210 can be set to 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 configured 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 follow the shape of the object S. The thickness of the plate-like member that constitutes one of the four links in the four-bar link mechanism 210 is preferably 8% or less, and more preferably 6% or less, of the length of the shortest link of the three links connected to that one link.

[0035] Furthermore, 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 set to a stress of 0.08 N or more at a deflection of 1.5 mm during three-point bending. This allows the four-bar link mechanism 210 to be configured with excellent flexibility, and 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 during three-point bending.

[0036] Furthermore, in the link mechanism device 200, the plate-like members constituting the links of 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 constructed with light weight and excellent flexibility. 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.

[0037] (Example of Manufacturing Method of Link Mechanism Device 200) A manufacturing method of the link mechanism device 200 will be described using an example in which hinges are used as the joint members.

[0038] (1) First, prepare a hinge and cut out a link to match the width of the hinge (the length of the short side of the hinge).

[0039] (2) Next, holes for attaching the hinges are formed in the links.

[0040] (3) Next, for the links located on the inside (toward 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, or the like can be used as the material for the hinges. Screws, adhesives, or the like can be used to attach the hinges to the links.

[0041] (4) Next, when providing a tip link at the tip end of the four-bar link mechanism 210 located at the most tip end side (opposite the drive unit 220 side), the tip link is attached to the tip end side of the four-bar link mechanism 210.

[0042] (5) Next, the drive unit 220 and the first four-bar link mechanism 211 are connected.

[0043] By following the above procedure, the link mechanism device 200 can be manufactured.

[0044] <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.

[0045] 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 the relationship A1 + B1 = C1 + D1. Although the link mechanism device 200X according to the comparative example does not apply to the embodiment, for ease of understanding, components having substantially the same functions as those included in the link mechanism device 200 according to the first embodiment are denoted by the same reference numerals 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 also apply to the comparative examples described below.

[0046] 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 tilts toward the object S so as to rotate about the first inner node J12. However, the first inner link L13 does not rotate about the first inner node J12 and does not tilt toward the object S, so it does not come into contact with the object S. Therefore, no force corresponding to the first inner link L13 contacting the object S is generated, 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.

[0047] (Second Comparative Example) A link mechanism device according to a second comparative example will be described with reference to Figures 5 and 6. Figure 5 is a schematic diagram showing an example of the configuration of a link mechanism device 200Y according to the second comparative example. Figure 6 is a schematic diagram showing an example of the operation of the link mechanism device 200Y.

[0048] 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.

[0049] 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 tilts toward the object S so as to rotate about the first inner node J12. However, the first inner link L13 does not rotate about the first inner node J12 and does not tilt toward the object S, so it does not come into contact with the object S. Therefore, no force corresponding to the first inner link L13 contacting the object S is generated, and the second four-bar link mechanism 212 is not driven and 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.

[0050] [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 components, and detailed descriptions will be omitted as appropriate. This also applies to the embodiments and modified examples described below.

[0051] Fig. 7 is a schematic diagram showing an example of the configuration of a 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.

[0052] The link mechanism device 200A differs from the link mechanism device 200 of the first embodiment mainly in that the multiple four-bar link mechanisms 210 further include a third four-bar link mechanism 213 connected to the tip side of the second four-bar link mechanism 212.

[0053] 7 to 9, the third four-bar link mechanism 213 includes a third outer link L31 located on the side opposite 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 side of the object S when it comes into contact with the object S, and a third tip-side link L34 located on the side opposite the driving unit 220. 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.

[0054] In the example shown in Figures 7 to 9, the second outer link L21, the third outer link L31, and the third driving link L32 are connected by a third outer node J31. The second inner link L23, the third driving 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, which are 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 driving side link L32 can be used interchangeably.

[0055] In the link mechanism device 200A illustrated in Figures 7 to 9, when the first four-bar link mechanism 211 is driven by the drive unit 220 and comes into contact with the object S, forces T21 and T22 generated in response to this contact drive the second four-bar link mechanism 212 that is connected to the first four-bar link mechanism 211 on the distal side. The driven second four-bar link mechanism 212 comes into contact with the object S. Forces T31 and T32 generated in response to the second four-bar link mechanism 212 coming into contact with the object S drive the third four-bar link mechanism 213 that is connected to the second four-bar link mechanism 212 on the distal side. The driven third four-bar link mechanism 213 comes into contact with the object S.

[0056] This will be explained in more detail. In the example shown in Figure 7, a force F1 is applied from the drive unit 220 to the first outer node J11 in a direction toward the distal end. The application of the force F1 causes the first outer node J11 to move toward the distal end. As the first outer node J11 moves, a force T11 that rotates the first drive link L12 about the first inner node J12 acts on the first drive link L12, causing the first drive link L12 to tilt toward the object S. Furthermore, as the first outer node J11 moves, a force T12 that rotates the first inner link L13 about the first inner node J12 acts on the first inner link L13, causing the first inner link L13 to tilt toward the object S. As a result, the first inner link L13 comes into contact with the object S.

[0057] When the first inner link L13 comes into contact with the object S, as shown in Figure 8, a force T21 that rotates the second driving-side link L22 about the second inner node J22 acts on the second driving-side link L22, causing the second driving-side link L22 to tilt toward 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 about the second inner node J22 acts on the second inner link L23, causing the second inner link L23 to tilt toward the object S. As a result, the second inner link L23 comes into contact with the object S.

[0058] When the second inner link L23 comes into contact with the object S, as shown in Figure 9, a force T31 acts on the third driving-side link L32 to rotate it about the third inner node J32, causing the third driving-side link L32 to tilt toward the object S. Furthermore, when the second inner link L23 comes into contact with the object S, a force T32 acts on the third inner link L33 to rotate it about the third inner node J32, causing the third inner link L33 to tilt toward the object S. As a result, the third inner link L33 comes into contact with the object S.

[0059] When the third inner link L33 comes into contact with the object S, as shown in Figure 9, a force T41 acts on the third tip side link L34, rotating it about the fourth inner node J42, causing the third tip side link L34 to tilt toward 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, rotating it about the fourth outer node J41, causing the tip link P to tilt toward the object S. As a result, the tip link P comes into contact with the object S.

[0060] In the link mechanism device 200A, a force generated when the four-bar link mechanism 210 located on the drive unit 220 side comes into contact with the object S sequentially acts on the four-bar link mechanisms 210 connected on the tip side. This allows the four-bar link mechanisms 210 on the tip side to come into contact with the object S sequentially. The multiple four-bar link mechanisms 210, starting with the four-bar link mechanism 210 on the drive unit 220 side, come into contact with the object S sequentially, thereby taking on a shape that follows the shape of the object S. In this way, the link mechanism device 200A can drive the multiple four-bar link mechanisms 210 so that they follow the shape of the object S. In other words, in this embodiment, a link mechanism device 200A can be provided that can drive the multiple four-bar link mechanisms 210 so that they follow the shape of the object S using one drive unit 220, which is fewer than the three four-bar link mechanisms 210.

[0061] Other operational effects of the link mechanism device 200A than those described above are similar to those of the link mechanism device according to the first embodiment.

[0062] [Modifications] Various modifications of the link mechanism device according to the embodiment will be described below.

[0063] 10 is a schematic diagram showing an example of the configuration of a link mechanism device 200B according to a first modification. 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.

[0064] With the above configuration, the drive unit 220 can drive the first four-bar 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-bar link mechanism 211 in this manner, the first four-bar link mechanism 211 can bring the first inner link L13 of the first four-bar link mechanism 211 into contact with the object S.

[0065] The effects of the link mechanism device 200B are similar to those of the link mechanism device according to the first embodiment.

[0066] 11 is a schematic diagram showing an example of the configuration of a link mechanism device 200C according to a second modification. The link mechanism device 200C differs from the above-described embodiment and modifications 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 away from the drive unit 220 and moves the first inner node J12 toward the drive unit 220.

[0067] With the above configuration, the drive unit 220 can drive the first four-bar link mechanism 211 while varying the relative position of the first outer node J11 and the first inner node J12. By this drive, the first four-bar link mechanism 211 can bring the first inner link L13 of the first four-bar link mechanism 211 into contact with the object S.

[0068] The effects of the link mechanism device 200C are similar to those of the link mechanism device according to the first embodiment.

[0069] 12 is a schematic diagram showing an example of the configuration of a link mechanism device 200D according to a third modification. The link mechanism device 200D differs from the above-described embodiment and modifications in that it satisfies the conditions A1 + B1 > C1 + D1, as well as A1 < B1 and C1 < D1. The link mechanism device 200C also provides the same effects as the first embodiment.

[0070] 13 is a schematic diagram showing an example of the configuration of a link mechanism device 200E according to a fourth modification. The link mechanism device 200E differs from the above-described embodiment and modifications 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 drive units 220 is less than the number of four-bar link mechanisms 210.

[0071] 13 , the multiple four-bar link mechanisms 210 include a first four-bar link mechanism 211, a second four-bar link mechanism 212, a third four-bar link mechanism 213, a fourth four-bar link mechanism 214, a fifth four-bar link mechanism 215, and a sixth four-bar link mechanism 216. The drive unit 220 includes a first drive unit 221, a second drive unit 222, and a third drive unit 223.

[0072] In the example shown in FIG. 13 , the first drive unit 221 is connected to the first four-bar link mechanism 211. The second four-bar link mechanism 212 is connected to the distal end of the first four-bar link mechanism 211. The second drive unit 222 is connected to the distal end of the second four-bar link mechanism 212. The second drive unit 222 is connected to the third four-bar link mechanism 213. The fourth four-bar link mechanism 214 is connected to the distal end of the third four-bar link mechanism 213. The third drive unit 223 is connected to the distal end of the fourth four-bar link mechanism 214. The third drive unit 223 is connected to the fifth four-bar link mechanism 215. The sixth four-bar link mechanism 216 is connected to the distal end of the fifth four-bar link mechanism 215.

[0073] 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 contact of the first four-bar link mechanism 211 with the object S. The position of the second drive unit 222 connected to the tip end of the second four-bar link mechanism 212 is variable in response to the driving 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 contact of the third four-bar link mechanism 213 with the object S. The position of the third drive unit 223 connected to the tip end of the third four-bar link mechanism 213 is variable in response to the driving 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 linkage 216 is driven by a force generated in response to the fifth four-bar linkage 215 coming into contact with the object S.

[0074] In the link mechanism device 200E, the six four-bar link mechanisms 210 can be driven so as to follow the shape of the object S. From another perspective, in the link mechanism device 200 according to the embodiment, even when the link mechanism device 200 has multiple drive units 220, it is possible to drive the multiple four-bar link mechanisms 210 so as to follow the shape of the object S, as long as the number of drive units 220 is less than the number of the multiple four-bar link mechanisms 210. 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."

[0075] 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.

[0076] Other operational effects of the link mechanism device 200D than those described above are similar to those of the link mechanism device 200 according to the first embodiment.

[0077] 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, second embodiment, first modified example, second modified example, third modified example, and fourth modified example.

[0078] <Configuration Example of Robot According to Third Embodiment> The configuration of a 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 a robot 100 according to the third embodiment. Fig. 15 is a schematic side view showing an example of a robot 100. Fig. 16 is a schematic cross-sectional view taken along line XVI-XVI in Fig. 15.

[0079] The robot 100 has an exterior member 10 and is capable of being driven by supplied power. The robot 100 illustrated in this embodiment is a doll-type communication robot modeled after a bear cub. The robot 100 is manufactured to have a size and weight suitable for being held by a user. Here, the term "user" refers to a user of the robot 100. Typical examples of users include working adults living alone, seniors whose children have become independent, and frail elderly people who are recipients of home medical care. The user may include not only the user of the robot 100, but also a person who simply comes into contact with the robot 100, such as the manager of the robot 100.

[0080] The exterior member 10 is flexible. The exterior member 10 contains, for example, a soft material that is comfortable to the touch when the user of the robot 100 touches the robot 100. The material of the exterior member 10 can be an organic material such as urethane foam, rubber, resin, or fiber. The exterior member 10 is preferably composed of an exterior such as a urethane foam material having thermal insulation properties and a soft cloth material covering the outer surface of the exterior.

[0081] 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 main body. The head 2, arms 3, and legs 4 each correspond to a driver connected to the robot main body so as to be displaceable relative to the robot main body.

[0082] 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 neck, torso, etc. of the user as if embracing the user. This action makes the user feel a sense of closeness to the robot 100, thereby promoting interaction between the user and the robot 100. Note that interaction with the user refers to an action of mutual contact (contact action) between the user and the robot 100, such as stroking, tapping (touching), hugging (embracing), etc.

[0083] The torso 1, head 2, arms 3, and legs 4 are all covered with an exterior member 10. The exterior member of the torso 1 and the exterior member of the arms 3 are integrated, and the exterior members of the head 2 and legs 4 are separate from the exterior members of the torso 1 and arms 3. However, this configuration is not limited to this, 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 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 move may not include components such as sensors inside them and may be composed only of the exterior member 10.

[0084] 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.

[0085] The robot 100 also has a display 24, a speaker 25, and a light 26 inside the exterior member 10 of the head 2. The robot 100 also has displays 24 inside the exterior member 10 of the right eye 2a and the left eye 2b. In addition, the robot 100 has a speaker 25 inside the exterior member 10 of the mouth 2c, and a light 26 inside the exterior member 10 of the right cheek 2d and the left cheek 2e.

[0086] 16 , the robot 100 has a torso frame 16, a torso mount 17, a right arm drive unit 220a, and a left arm drive unit 220b inside the armor member 10 of the torso 1. The robot 100 also has a head frame 22 and a head mount 23 inside the armor member 10 of the head 2. The robot 100 also has a plurality of right arm four-joint link mechanisms 210a inside the armor member 10 of the right arm 3a, and a plurality of right arm four-joint link mechanisms 210a inside the armor member 10 of the left arm 3b. In addition, the robot 100 has a right leg frame 42a inside the armor member 10 of the right leg 4a, and a left leg frame 42b inside the armor member 10 of 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, while the left arm drive unit 220b and the multiple left arm four-joint link mechanisms 210b constitute a left arm link mechanism device 200b.

[0087] The torso frame 16, the head frame 22, the right leg frame 42a, and the left leg frame 42b are each a structure formed by combining multiple columnar members. The torso support platform 17 and the 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, the head frame 22, the right leg frame 42a, and the left leg frame 42b may be formed in a box shape including multiple plate-like members.

[0088] The multiple right arm four-bar link mechanisms 210a are connected to the torso frame 16 via a right arm drive unit 220a. The right arm four-bar link mechanisms 210a are driven by the right arm drive unit 220a and are therefore displaceable relative to the torso frame 16. Displacement of the right arm four-bar link mechanisms 210a displaces the right arm 3a 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.

[0089] The multiple left arm four-bar link mechanisms 210b are connected to the torso frame 16 via left arm drive units 220b. The left arm four-bar link mechanisms 210b are driven by the left arm drive units 220b and are therefore displaceable relative to the torso frame 16. Displacement of the left arm four-bar link mechanisms 210b displaces the left arm 3b relative to the torso 1. The left arm drive units 220b preferably have, for example, a reducer that increases the output torque of the left arm drive units 220b.

[0090] The right arm link mechanism device 200a can drive the multiple right arm four-bar link mechanisms 210a so as to follow the shape of the object S, using a smaller number of right arm drivers 220a than the multiple right arm four-bar link mechanisms 210a. The left arm link mechanism device 200b can drive the multiple left arm four-bar link mechanisms 210b so as to follow the shape of the object S, using a smaller number of left arm drivers 220b than the multiple left arm four-bar link mechanisms 210b. This makes it possible to configure the right arm link mechanism device 200a and the left arm link mechanism device 200b inexpensively, compactly, and lightweightly, and to simplify the configuration of the right arm link mechanism device 200a and the left arm link mechanism device 200b. Furthermore, since the arm 3 has the right arm link mechanism device 200a and the left arm link mechanism device 200b, the robot 100 can be configured inexpensively, compactly, and lightweightly, and the configuration of the robot 100 can be simplified.

[0091] In the example shown in FIGS. 14 to 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 a user holds the robot 100 and brings the robot 100 into contact with the user's torso, the multiple right arm four-bar link mechanisms 210a and the multiple left arm four-bar link mechanisms 210b are driven to follow the shape of the user's torso, which is the object S. As a result, the multiple right arm four-bar link mechanisms 210a and the multiple left arm four-bar 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. With the right arm 3a and the left arm 3b 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.

[0092] The head frame 22 is connected to the body frame 16 via a head connection mechanism 27, and is driven by a head servomotor 35c to be displaceable relative to the body frame 16. Displacement of the head frame 22 displaces the head 2 relative to the body 1. The head connection mechanism 27 preferably has, for example, a reducer that increases the output torque of the head servomotor 35c.

[0093] 14 to 16, the head frame 22 includes a neck frame F1c and a face frame F2c. The torso frame 16, the neck frame F1c, and the face frame F2c are connected to each other via connecting mechanisms.

[0094] The head servomotor 35c is a general term for multiple servomotors. For example, the head servomotor 35c has a neck servomotor M1c and a face servomotor M2c. The neck servomotor M1c rotates the neck frame F1c around a rotation axis perpendicular to the body frame 16. The face servomotor M2c rotates the face frame F2c around a rotation axis perpendicular to the rotation axis of the neck frame F1c.

[0095] By providing the head 2 with two-axis joints in this way, the robot 100 can achieve more realistic movements.

[0096] 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, the robot 100 preferably has two right leg wheels 41a in the front-to-rear direction of the right leg frame 42a. The right leg wheels 41a are 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.

[0097] 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, the robot 100 preferably 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 a rotation axis 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, for example, a reducer that increases the output torque of the left leg servo motor 35e.

[0098] 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.

[0099] In this way, the legs 4 enable the robot 100 to perform movements with a higher degree of realism.

[0100] 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 on which the tactile sensor 12 and the vital sensor 14 are fixed. Note that the placement 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 on the torso mounting base 17 on which the tactile sensor 12 and the vital sensor 14 are fixed, the center of gravity of the robot 100 will be lower because the battery 15 is heavier than the other components. A lower center of gravity of the robot 100 is preferable because it stabilizes at least one of the position and posture of the robot 100 and makes it easier to charge and replace the battery 15.

[0101] 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.

[0102] 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, 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, adhesive members, etc.

[0103] 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 materials, metal materials, etc. can be used. However, from the perspective of ensuring strength during operation, 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 materials 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.

[0104] The control unit 13 is communicably connected to each of the camera 11, tactile sensor 12, vital sign sensor 14, first capacitance sensor 21, second capacitance sensor 31, and head servo motor 35c by wire or wirelessly. The control unit 13 is also communicably connected to each of the right eye display 24a, left eye display 24b, speaker 25, right cheek light 26a, and left cheek light 26b by wire or wirelessly.

[0105] The camera 11 is an image sensor that outputs a captured image of the periphery of the robot 100 to the control unit 13. The camera 11 includes a lens and an imaging element that captures an image through the lens. A CCD (Charge Coupled Device) or a CMOS (Complementary Metal-Oxide Semiconductor) can be used as the imaging element. The captured image may be either a still image or a video image.

[0106] Furthermore, the camera 11 is preferably configured as 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 the 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. The captured image is an example of a captured image of a user. In addition to the camera 11, the robot 100 may also 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 rang- ing) sensor.

[0107] The tactile sensor 12 is a sensor element that detects information sensed by the sense of touch of a human hand, 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 on pressure or vibration generated when a user touches 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 with or presence of the robot 100.

[0108] The vital sensor 14 is an example of an electromagnetic wave sensor that acquires biometric information of a user using electromagnetic waves.

[0109] The first capacitance sensor 21 and the second capacitance sensor 31 are sensor elements that detect, based on a change in capacitance, that a user has come into contact with or proximity to the robot 100 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. Because the arm portion 3 is a part that is likely to be touched by a user, the second capacitance sensor 31 is preferably a flexible sensor that includes conductive thread or the like in terms of improving the feel to the touch. 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.

[0110] The right eye display 24a and the left eye display 24b are display modules that display character strings 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 configured, for example, by liquid crystal display modules. The character strings 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, if a user is sitting with happy emotions, the robot 100 can display a "smiling" image on the right eye display 24a and the left eye display 24b to empathize with the happiness, thereby implicitly inducing contact with the user.

[0111] The speaker 25 is a speaker unit that amplifies an audio signal from the control unit 13 and outputs the audio. The audio 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 interaction with the user by outputting a voice of "making a (worried) voice" from the speaker 25 to a user who is doing housework and feeling sad.

[0112] 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 configured, for example, by LED (Light Emitting Diode) light modules. 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, if a user is sitting and feeling sad, the robot 100 can express empathy by making the right cheek light 26a and the left cheek light 26b blink blue, thereby enabling the robot 100 to take an action that induces interaction with the user.

[0113] The battery 15 is a power source that supplies power to the camera 11, tactile sensor 12, control unit 13, vital sign 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.

[0114] 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 is only required 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 arranged 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.

[0115] 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 communicate with each device wirelessly from outside the exterior member 10. The battery 15 can also supply power to each component from outside the exterior member 10.

[0116] In this embodiment, a configuration in which the head 2, arms 3, and legs 4 are movable is exemplified, but this is not limiting, and at least one of the head 2, arms 3, and legs 4 may be movable. It is preferable that an end effector such as a hand can be connected to the arms 3. Furthermore, although the legs 4 are configured using wheels, they may also be configured using crawlers, legs, or the like.

[0117] The configuration and shape of the robot 100 are not limited to those illustrated in Figures 14 to 16, and can be changed as appropriate depending on 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 robot, instead of a form resembling a bear cub. 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, a light, and the like.

[0118] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0119] Furthermore, all ordinal numbers, quantitative numbers, and other figures used in the above-described embodiments are merely examples for specifically explaining the technology of the present invention, and the present invention is not limited to the exemplified figures. Furthermore, the connection relationships between the components are merely examples for specifically explaining the technology of the present invention, and the connection relationships for realizing the functions of the present invention are not limited to these.

[0120] The link mechanism device according to the embodiment can be suitably used in a robot, a transport mechanism, a transport device, etc. The link mechanism device according to the embodiment can drive a plurality of four-bar link mechanisms so as to follow the shape of an object using a number of drive units that is fewer than the number of the plurality of four-bar link mechanisms, and therefore 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.

[0121] Furthermore, the robot according to the embodiment is particularly suitable for use in providing comfort (a sense of security or self-affirmation) by promoting oxytocin secretion in working people living alone, seniors whose children have become independent, frail elderly people who are recipients of home medical care, etc. However, the robot according to the embodiment is not limited to this use, and can also be used favorably as an industrial robot, etc.

[0122] The aspects of the present disclosure are as follows, for example: <1> A device having a plurality of four-bar link mechanisms connected to each other and a drive unit that drives the four-bar link mechanisms, wherein 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 connected to the first four-bar link mechanism, wherein the first four-bar link mechanism includes a first outer link located on the side opposite to the object when contacting the object, a first drive-side link located on the drive unit side, a first inner link located on the object when contacting the object, and a first tip-side link located on the side opposite to the drive unit, and the second four-bar link mechanism includes a second outer link located on the side opposite to the object when contacting the object, and a second drive-side link located on the drive unit side. a first four-bar link mechanism including a first outer link, a second inner link positioned on the object side when it comes into contact with the object, and a second tip side link positioned opposite the drive unit side, wherein the drive unit is connected to at least one of a first outer node connecting an end of the first outer link to an end of the first drive side link and a first inner node connecting an end of the first drive side link to an end of the first inner link, and driving the first four-bar link mechanism to vary the relative position of the first outer node and the first inner node, wherein A1 + B1 > C1 + D1 is satisfied, where A1 is the length of the second outer link, B1 is the length of the second drive side link, C1 is the length of the second inner link, and D1 is the length of the second tip side link. <3> The link mechanism device according to <1>, wherein the drive unit is connected to the first inner node and moves the first inner node toward the drive unit. <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 made of a plate-like member. <5> The link mechanism device according to <4>, wherein the thickness of the plate-like member constituting one of the four links is 10% or less of the length of the shortest link of three links connected to the one link.<6> The link mechanism device according to <4> or <5>, wherein the flexibility of the plate-shaped member is a stress of 0.08 N or more at a deflection of 1.5 mm during three-point bending. <7> The link mechanism device according to any one of <4> to <6>, wherein the plate-shaped 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 plurality of 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 side opposite to the object when in contact with the object, a third drive-side link located on the drive unit side, a third inner link located on the object side when in contact with the object, and a third tip-side link located on the side opposite to the drive unit side, wherein, when a length of the third outer link is A2, a length of the third drive-side link is B2, a length of the third inner link is C2, and a length of the third tip-side link is D2, A2 + B2 > C2 + D2 is satisfied. <9> A robot having the link mechanism device according to any one of <1> to <8>.

[0123] 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.

[0124] REFERENCE SIGNS LIST 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 Tactile sensor 13 Control unit 14 Vital sensor 15 Battery 16 Torso frame 17 Torso mount 21 First capacitance sensor 22 Head frame 23 Head mount 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 servomotor 35d Right leg servomotor 35e Left leg servomotor 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-bar link mechanism 211 First four-bar link mechanism 212 Second four-bar link mechanism 213 Third four-bar link mechanism 214 Fourth four-bar link mechanism 215 Fifth four-bar link mechanism 216 Sixth four-bar link mechanism 210a Right arm four-bar link mechanism 210b Left arm four-bar 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 motor 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 drive side link L13 First inner link L14 First tip side linkL21: 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

1. A system having 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 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 side when in contact with the object, and a first tip side link located on the side opposite to the drive unit, the second four-bar link mechanism including a second outer link located on the side opposite to the object when in contact with the object, a second drive side link located on the drive unit side, a second inner link located on the object side when in contact with the object, and a second tip side link located on the side opposite to the drive unit, the drive section is connected to at least one of a first outer node section connecting an end of the first outer link and an end of the first driving side link and a first inner node section connecting 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; wherein, where 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, then A1 + B1 > C1 + D1 is satisfied.

2. A link mechanism device as described in claim 1, wherein the drive unit is connected to the first outer node portion and moves the first outer node portion in a direction opposite to the drive unit side.

3. A link mechanism device as described in claim 1, wherein the drive section is connected to the first inner node section and moves the first inner node section toward the drive section.

4. A link mechanism device as described in claim 1, wherein each of the four links included in each of the plurality of four-bar link mechanisms is formed of a plate-like member.

5. A link mechanism device as described in claim 4, wherein the thickness of the plate-like member constituting one of the four links is 10% or less of the length of the shortest link among the three links connected to said one link.

6. A link mechanism device according to claim 4, wherein the flexibility of said plate-like member is 0.08 N or more in terms of stress at a deflection of 1.5 mm when bent at three points.

7. 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.

8. The link mechanism device of claim 1, 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 side, wherein A2 + B2 > C2 + D2 is satisfied 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.

9. A robot having a link mechanism device according to any one of claims 1 to 8.

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