Wire-driven articulated structure

Abstract

This invention provides a wire-driven multi-joint structure that reduces the motor power required to stop rotation in specific joints that require a large motor torque to control rotation. [Solution] In the robot hand 10, one or more pulleys 60 in the pulley row 68 corresponding to the first joint 70A and the second joint 70B have a different radius from the other pulleys 60, and in the pulley row 68 corresponding to the first joint 70A and the second joint 70B, the sum of the radii of the first pulleys 60 that rotate the joint 70 clockwise when pulled by the motor 90 is equal to the sum of the radii of the second pulleys 60 that rotate the joint 70 counterclockwise when pulled by the motor 90.

Description

[Technical Field]

[0001] This disclosure relates to a wire-driven articulated structure. [Background technology]

[0002] For example, Patent Document 1 discloses a robot hand comprising a finger drive assembly that can be operated to selectively apply tension to four tension elements. Each finger assembly includes a series of link members that move by selective pulling / movement of the tension elements by the drive assembly. The links are pivotally connected to each other so as to have three degrees of freedom. The finger assembly comprises a series of pulleys that support and guide the tension elements through the finger assembly. The tension elements partially extend around the pulleys, thereby allowing the finger assembly to perform n+1 drives in a non-helical winding of the tension elements. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2010-240834 [Overview of the project] [Problems that the invention aims to solve]

[0004] Incidentally, in prior art, there are cases where the torque required to drive certain joints is insufficient. These specific joints include, in particular, the first joint connecting the base to the first link connected to the base, and the second joint connecting the first joint to the first joint. This is because, in a multi-joint drive structure where links are connected in a chain, the first and second joints require a large amount of pre-tension to ensure joint rigidity.

[0005] This disclosure provides a wire-driven articulated joint structure that reduces the motor power required to stop rotation for specific joints that require a large motor torque to control rotation. [Means for solving the problem]

[0006] The wire-driven articulated structure of the first embodiment comprises a base; a plurality of links connected to the base and having a first link that rotates relative to the base via a first joint, and a second link connected to the first link and rotating relative to the first link via a second joint; a plurality of motors arranged on the base, the number of which exceeds the total number of the plurality of joints and is less than twice the total number of the plurality of joints; a plurality of wires, one end of which is attached to each of the plurality of motors and the other end of which is attached to any of the links included in the plurality of links; and a row of winding members having a plurality of winding members aligned with the axis of rotation of the plurality of joints, wherein one or more of the winding members included in the row of winding members corresponding to the first joint and the second joint have a different winding radius from the other winding members, and the row of winding members corresponding to the first joint and the second joint, respectively, has a sum of winding radii of first winding members that rotate the joint in a first direction when pulled by a motor equals the sum of winding radii of second winding members that rotate the joint in a second direction when pulled by a motor.

[0007] In this embodiment of the wire-driven articulated structure, the sum of the winding radii of the winding members that rotate the joint in the first direction is equal to the sum of the winding radii of the winding members that rotate the joint in the second direction, for the winding member rows corresponding to the first and second joints. Therefore, in this embodiment of the wire-driven articulated structure, the rotation of the first and second joints comes to a standstill when the tension applied to the wires that rotate the first and second joints by the respective motors is equal. Here, the torque required to rotate the first and second joints tends to be large. In other words, in this embodiment of the wire-driven articulated structure, it is possible to reduce the motor power required to stop the rotation of the first and second joints, which are specific joints that require a large motor torque to control rotation.

[0008] The wire-driven articulated structure of the second embodiment is the wire-driven articulated structure of the first embodiment, wherein in all joints including the first and second joints, the sum of the winding radii of the first winding members is equal to the sum of the winding radii of the second winding members.

[0009] In this embodiment of the wire-driven articulated structure, the sum of the winding radii of the first winding members is equal to the sum of the winding radii of the second winding members in all winding member rows. Therefore, in this embodiment of the wire-driven articulated structure, the rotation of each joint comes to a standstill when the tension applied to the wires that rotate each joint by each motor is equal. In other words, in this embodiment of the wire-driven articulated structure, the motor power required to stop the rotation of all joints can be reduced.

[0010] The third embodiment of the wire-driven articulated structure is the wire-driven articulated structure described in the first or second embodiment, wherein the total number of wires is one greater than the total number of joints.

[0011] According to this embodiment of the wire-driven articulated structure, the drive control can be simplified compared to the case where the total number of wires is two or more times greater than the total number of joints.

[0012] The fourth aspect of the wire-driven articulated structure is the wire-driven articulated structure described in the first or second aspect, wherein the base portion has a plurality of first links connected to each of the plurality of first joints, and a plurality of second links that rotate relative to the plurality of first links via a plurality of second joints.

[0013] In this embodiment, the wire-driven articulated structure has a base with a plurality of first links and a plurality of second links that rotate relative to the plurality of first links. In other words, according to this embodiment, a wire-driven articulated structure is obtained in which a plurality of components are driven relative to the base.

[0014] The fifth aspect of the wire-driven articulated structure is the wire-driven articulated structure described in the fourth aspect, wherein the base has a plurality of base internal links and a base internal joint that rotates the plurality of base internal links relative to each other, and the base internal joint has a base internal winding member row around which all the wires wound around the plurality of first joints are wound.

[0015] In this embodiment of the wire-driven articulated structure, the base has an internal joint, allowing the base to be rotationally deformed. Therefore, according to this embodiment of the wire-driven articulated structure, the positions of multiple first and second links can be controlled by controlling the rotation of the internal joint.

[0016] The sixth aspect of the wire-driven articulated structure is the wire-driven articulated structure described in the fifth aspect, wherein the total number of first links is even, the first winding member of the winding member row corresponding to the base internal joint has wires wound around it that connect to half of the first links in the plurality of first links, the second winding member of the winding member row corresponding to the base internal joint has wires wound around it that connect to the remaining half of the first links in the plurality of first links, and the sum of the winding radii of the first winding members of the base internal joint is equal to the sum of the winding radii of the second winding members.

[0017] According to the wire-driven multi-joint structure according to this aspect, in the wire-driven multi-joint structure in which the total number of the first links is an even number, the drive control of the base internal joint can be simplified.

[0018] The wire-driven multi-joint structure of the seventh aspect is the wire-driven multi-joint structure described in the fifth aspect, wherein the total number of the first links is an odd number, and at least one of the wires connected to a specific link included in the first links and half of the plurality of first links excluding the specific link are wound around the first winding member included in the winding member row corresponding to the base internal joint, and the remaining of the wires connected to the specific link and the remaining half of the plurality of first links excluding the specific link are wound around the second winding member included in the winding member row corresponding to the base internal joint, and the sum of the winding radii of the first winding members of the base internal joint is equal to the sum of the winding radii of the second winding members.

[0019] According to the wire-driven multi-joint structure according to this aspect, in the wire-driven multi-joint structure in which the total number of the first links is an odd number, the drive control of the base internal joint can be simplified.

[0020] The wire-driven multi-joint structure of the eighth aspect is the wire-driven multi-joint structure described in any one of the first to seventh aspects, wherein all of the plurality of motors have equal rated capacities.

[0021] According to the wire-driven multi-joint structure according to this aspect, compared with the case where the rated capacities of the plurality of motors are different, the drive control can be simplified.

[0022] The wire-driven multi-joint structure of the ninth aspect is the wire-driven multi-joint structure described in any one of the first to eighth aspects, and has a pair of winding member rows whose rotation axis directions are orthogonal to each other, and the tangents of the winding members included in one of the pair of winding member rows all coincide with the tangents of the winding members included in the other winding member row of the pair of winding member rows.

[0023] In this embodiment of the wire-driven articulated structure, there is a pair of winding member rows whose rotational axis directions are perpendicular to each other, and the winding members included in the pair of winding member rows have tangential directions that coincide with each other. Therefore, the wires that span between the pair of winding member rows coincide with the rotational direction of the winding members, and thus the wires do not move in the direction of the rotational axis of the winding members. In other words, in this embodiment of the wire-driven articulated structure, wires can be spanned between winding members without using other idlers.

[0024] The tenth aspect of the wire-driven articulated structure is the wire-driven articulated structure described in the ninth aspect, wherein the pair of winding member rows are arranged such that the winding radius decreases sequentially from both sides in the direction of the rotation axis toward the inside.

[0025] The eleventh wire-driven articulated structure is the wire-driven articulated structure described in the ninth aspect, wherein one row of winding members consists of a first winding member with radius r1 and a second winding member with radius r2, separated by a length r3 from the center of the first row of winding members, and a second row of winding members consisting of a first winding member with radius r2 and a second winding member with radius r1, separated by a length r4 from the center of the first row of winding members, and the other row of winding members consists of a first winding member with radius r3 and a second winding member with radius r4, separated by a length r1 from the center of the other row of winding members, and a second row of winding members consisting of a first winding member with radius r4 and a second winding member with radius r3, separated by a length r2 from the center of the other row of winding members.

[0026] The twelfth aspect of the wire-driven articulated structure is a wire-driven articulated structure according to any one aspect of the first to ninth aspects, wherein the number of winding members in at least one winding member row is odd.

[0027] In this embodiment of the wire-driven articulated structure, the degree of design freedom can be improved.

[0028] The thirteenth aspect of the wire-driven articulated structure is the wire-driven articulated structure described in the twelfth aspect, wherein in a row of winding members having an odd number of winding members, the difference between the number of winding members that rotate the joint in the first direction and the number of winding members that rotate the joint in the second direction is 1.

[0029] In this embodiment of the wire-driven articulated structure, the degree of design freedom can be improved.

[0030] The fourteenth aspect of the wire-driven articulated structure is a wire-driven articulated structure according to the third aspect or any one of the eighth to twelfth aspects that reference the third aspect, wherein the row of winding members corresponding to the joint that rotates the link furthest from the base among a plurality of links connected sequentially from the base has one first winding member and one second winding member, and the row of winding members corresponding to each joint that rotates the plurality of links connected sequentially from the base has one more winding member in each subsequent row, starting from the row of winding members that rotates the link furthest from the base, and the number of winding members in either the first winding member or the second winding member in the row of winding members is 1, and each of the winding members has a wire wound around it, the other end of which is fastened to the link that the joint corresponding to the winding member rotates relatively.

[0031] In this wire-driven articulated structure, it is easy to control multiple joints independently. [Effects of the Invention]

[0032] According to this disclosure, a wire-driven articulated joint structure is obtained that reduces the motor power required to stop rotation for specific joints that require a large motor torque to control rotation. [Brief explanation of the drawing]

[0033] [Figure 1] This is a perspective view showing a robot hand according to the first embodiment of this disclosure. [Figure 2]Following Figure 1, this figure shows a robot hand according to the first embodiment of this disclosure, and is a perspective view showing the pulleys and wires arranged inside. [Figure 3] Following Figure 2, this figure shows a robot hand according to the first embodiment of this disclosure, and is a side view showing how a wire is wrapped around a pulley located inside. [Figure 4] Following Figure 3, this figure shows a robot hand according to the first embodiment of this disclosure, illustrating an example in which the robot hand deforms by rotating one joint. [Figure 5] Following Figure 3, this figure shows a robot hand according to the first embodiment of this disclosure, illustrating an example in which the robot hand deforms by rotating another joint. [Figure 6] Following Figure 3, this figure shows a robot hand according to the first embodiment of this disclosure, illustrating an example of a robot hand deforming by rotating two joints. [Figure 7] This figure shows a robot hand according to a modification of the first embodiment of the present disclosure, illustrating how a wire is attached to a pulley. [Figure 8] This is a perspective view showing a robot hand according to a second embodiment of this disclosure. [Figure 9] Following Figure 8, this figure shows a robot hand according to the second embodiment of this disclosure, and is a perspective view showing the pulleys and wires arranged inside. [Figure 10] Following Figure 9, this figure shows a robot hand according to the second embodiment of the present disclosure, and is a perspective view showing two orthogonal pulley rows. [Figure 11] Following Figure 10, this figure shows a robot hand according to the second embodiment of the present disclosure, and is a side view showing how a wire is wrapped around a pulley located inside. [Figure 12] Following Figure 11, this figure shows a robot hand according to the second embodiment of the present disclosure, and is a plan view showing how a wire is wrapped around a pulley located inside. [Figure 13]This figure shows a robot hand according to a modified example of the second embodiment of the present disclosure, and is a perspective view showing two orthogonal rows of pulleys. [Figure 14] This is a perspective view showing a robot hand according to a third embodiment of this disclosure. [Figure 15] Following Figure 14, this figure shows a robot hand according to the third embodiment of this disclosure, and is a front view showing the pulley and wire arranged inside the base. [Figure 16] This is a perspective view showing a robot hand according to a modified example of the third embodiment of this disclosure. [Figure 17] Following Figure 16, this figure shows a modified robot hand according to the third embodiment of the present disclosure, and is a front view showing the pulley and wire arranged inside the base. [Modes for carrying out the invention]

[0034] Hereinafter, an example of an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, identical or equivalent components and parts are given the same reference numerals. Also, the dimensional ratios in the drawings are exaggerated for illustrative purposes and may differ from the actual ratios. In each drawing, the X, Y, and Z directions are all orthogonal to each other.

[0035] [First Embodiment] (composition) Figures 1 and 2 show a robot hand 10 of a first embodiment, which is an example of the wire-driven articulated structure of the present disclosure. Figure 3 is a schematic diagram showing the arrangement of the components of the robot hand 10 according to this embodiment. As shown in Figures 1 and 2, the robot hand 10 in this embodiment is an articulated structure driven by the tension of a wire 92. The robot hand 10 comprises a base 20, a first link 40A and a second link 40B, and a first joint 70A and a second joint 70B. Note that the wire 92 is not shown in Figure 1.

[0036] As shown in Figures 1 to 3, the base 20 is a component of the robot hand 10 where the motor 90 for winding the wire 92 is located. Also as shown in Figures 1 to 3, the base 20 is provided with multiple motors 90. In this embodiment, the motors 90 are a first motor 90A, a second motor 90B, and a third motor 90C, and each rotates individually under the control of a controller (not shown). Furthermore, by controlling the torque of the controller, it is possible to wind the first wire 92A connected to the first motor 90A, the second wire 92B connected to the second motor 90B, and the third wire 92C connected to the third motor 90C, respectively.

[0037] As shown in Figures 1 to 3, the robot hand 10 in this embodiment has multiple components with the same name. For example, for components with multiple components, such as the first motor 90A and the second motor 90B, the end of the reference numerals will be assigned the letters A, B, C, ... in order from the first component. Furthermore, hereafter, when the first motor 90A, the second motor 90B, and the third motor 90C are not distinguished, they will be referred to as "motor 90". Similarly, in the following description, for components with multiple components, the reference numeral at the end may be omitted to describe them without distinguishing between them. However, the reference numeral at the end of the pulley 60, which will be described later, will be determined separately.

[0038] Furthermore, the motor 90 and wire 92 of the robot hand 10 in this embodiment may be enclosed inside the outer shell that covers the base 20, as shown in Figures 1 and 2.

[0039] The first link 40A is a member that is rotatably connected to the base 20 via the first joint 70A, as shown in Figures 1 to 3. The first joint 70A is provided with a first pulley row 68A consisting of three pulleys 60: a first pulley 60A1, a second pulley 60A2, and a third pulley 60A3. All of the pulleys 60 in the first pulley row 68A have the same center of rotation (axis) and are capable of rotating in both clockwise (CW) and counterclockwise (CCW) directions. The first wire 92A is wrapped around the first pulley 60A1, the second wire 92B around the second pulley 60A2, and the third wire 92C around the third pulley 60A3. The end of the third wire 92C is attached to the first link 40A as shown in Figure 2. Note that the pulleys 60 in this embodiment are an example of a "wound member" in this disclosure.

[0040] Furthermore, in this embodiment, the pulley 60 and wire 92 of the robot hand 10 may be enclosed inside an outer shell covering the first link 40A and an outer shell covering the first joint 70A, as shown in Figures 1 and 2.

[0041] In this embodiment, as shown in Figure 2, the wire 92 is wound around the first pulley 60A1 from the top of the drawing, around the second pulley 60A2 from the bottom of the drawing, and around the third pulley 60A3 from the top of the drawing. In this embodiment, the pulleys 60 in the first pulley row 68A do not have the same radius. In this embodiment, as shown in Figure 2, the radius of the second pulley 60A2 is twice that of the first pulley 60A1 and the third pulley 60A3.

[0042] As shown in Figures 1 to 3, the first link 40A is equipped with idlers 62 around which the first wire 92A and the second wire 92B, which connect to the second link 40B, are wound. Both idlers 62 are capable of rotating in both clockwise and counterclockwise directions. Furthermore, as shown in Figures 1 to 3, the idlers 62 are components that change the direction in which the wires 92 extend.

[0043] The second link 40B is a member that is rotatably connected via the first joint 70A and the second joint 70B, as shown in Figures 1 to 3. The second joint 70B is provided with a second pulley row 68B consisting of two pulleys 60, the first pulley 60B1 and the second pulley 60B2. The pulleys 60 in the second pulley row 68B all have the same center of rotation (axis) and are capable of rotating in both clockwise and counterclockwise directions. The first wire 92A is attached to the first pulley 60B1, and the second wire 92B is attached to the second pulley 60B2. The ends of the first wire 92A and the second wire 92B are attached to the second link 40B shown in Figure 2.

[0044] Furthermore, in this embodiment, the pulley 60 and wire 92 of the robot hand 10 may be enclosed inside an outer shell covering the second link 40B and an outer shell covering the second joint 70B, as shown in Figures 1 and 2.

[0045] In this embodiment, as shown in Figure 2, the wire 92 is wound around the first pulley 60B1 from the bottom of the drawing, and the wire 92 is wound around the second pulley 60B2 from the top of the drawing. In this embodiment, the pulleys 60 in the second pulley row 68B have the same radius.

[0046] In this embodiment, each motor 90 applies torque to wind up the wire 92 while the robot hand 10 is in a controllable standby state, in other words, while maintaining the posture shown in Figure 3. In this embodiment, each motor 90 applies preliminary tension so that the tension on the wire 92 is the same for all motors 90. This tension will hereafter be referred to as "preliminary tension". The preliminary tension is the limit of tension that allows the wire 92 to maintain its posture without becoming slack relative to the pulley 60.

[0047] Furthermore, in this embodiment, the first motor 90A, the second motor 90B, and the third motor 90C are all motors 90 with the same rated output. For example, each motor 90 can be a motor 90 of the same model. In this embodiment, a DC motor is used as an example of the motor 90. In other words, in this embodiment, the torque of the motor 90 is controlled by a controller (not shown).

[0048] As shown in Figures 2 and 3, for each of the multiple pulleys 60, the last digit of their designation is assigned sequentially from the first pulley to the next, starting with 1, 2, 3, ... The letter immediately preceding the last digit corresponds to the letter of the joint 70 having the pulley row 68 in which the pulley 60 is located. Note that sometimes the pulley 60 is simply referred to as "pulley 60" without distinguishing between any of the multiple pulleys 60.

[0049] (Rotational drive of 70 joints) Next, with reference to Figures 3 and 4 through 6, a method for rotating each joint 70 in the robot hand 10 of this embodiment will be described.

[0050] As shown in Figure 3, the wire 92 is wound around the pulley 60 at a position radially away from the center of the rotation axis. Therefore, when the motor 90 winds up the wire 92, the wire 92 is pulled toward the base 20, reducing the length of the pulley 60 on the side around which the wire 92 is wound.

[0051] First, let's consider the second joint 70B. In the second joint 70B shown in Figure 3, when the torque of the first motor 90A is increased while maintaining the preliminary torque of the second motor 90B, and the first motor 90A winds up the first wire 92A, torque is generated in a direction that decreases the length between P0 and P1. Therefore, the second pulley row 68B, i.e., the second joint 70B, is driven counterclockwise. Similarly, in the second joint 70B, when the torque of the second motor 90B is increased while maintaining the preliminary torque of the first motor 90A, and the second motor 90B winds up the second wire 92B, torque is generated in a direction that decreases the length between P0 and P2. Therefore, the second joint 70B is driven clockwise.

[0052] Thus, in the robot hand 10 of this embodiment, by making the tension of one of the first wire 92A and the second wire 92B greater than the tension of the other in the second pulley row 68B, the second joint 70B can be rotated clockwise and counterclockwise, as shown in Figure 4. That is, in the second pulley row 68B, the first pulley 60B1 is a pulley 60 that rotates the second joint 70B counterclockwise, and the second pulley 60B2 is a pulley 60 that rotates the second joint 70B clockwise. Furthermore, the first pulley 60B1 that rotates the second joint 70B counterclockwise is an example of the first winding member in this embodiment, and the second pulley 60B2 that rotates the second joint 70B clockwise is an example of the second winding member in this embodiment. Similarly in the following explanation, a pulley 60 that rotates either joint 70 counterclockwise is an example of the "first winding member" in this disclosure, and a pulley 60 that rotates the joint 70 clockwise is an example of the "second winding member" in this disclosure.

[0053] Furthermore, if the torque that the first wire 92A uses to rotate the first pulley 60B1 is equal to the torque that the second wire 92B uses to rotate the second pulley 60B2, the second joint 70B will not rotate and will remain in the same position, as shown in Figure 3.

[0054] Here, the torque that the pulley 60 and wire 92 included in the second pulley row 68B exert on the second pulley row 68B is expressed by the following equation (1).

[0055]

number

[0056] In equation (1), n ​​is the torque (Nm) applied to the pulley row 68 by the pulley 60 and wire 92, R is the radius (m) of the pulley 60, and T is the tension (N) of the wire 92 applied to the pulley 60. The ±1 terms in equation (1) represent the direction of the torque applied to the pulley row 68 when tension is applied to the pulley 60. Specifically, a value of +1 is taken when the pulley 60 applies a clockwise torque to the pulley row 68, and a value of -1 is taken when the pulley 60 applies a counterclockwise torque to the pulley row 68. The subscript k in n, R, and T represents the k-th pulley 60 of the second pulley row 68B. In this embodiment, the radius of the pulley 60 is an example of the "winding radius of the winding member" in this disclosure. In other words, the fact that the radii of each pulley 60 in the second pulley row 68B are equal is an example of the fact that the winding radii in the second pulley row 68B are equal.

[0057] The torque applied to the second joint 70B by pulley 60, which is included in the second pulley row 68B, is expressed by the following equation (2).

[0058]

number

[0059] In equation (2), j is the total number of pulleys 60 in the second pulley row 68B (i.e., 2). As mentioned above, in the second pulley row 68B, the first pulley 60B1 and the second pulley 60B2 have the same radius. Therefore, in the second pulley row 68B, R kThe terms are equal for the first pulley 60B1 and the second pulley 60B2. In other words, the direction in which the second joint 70B is driven is determined by the tension applied to the first wire 92A and the second wire 92B.

[0060] In the case of the first joint 70A, similar to the second joint 70B, the first wire 92A, the second wire 92B, and the third wire 92C are wound around the first pulley row 68A. Furthermore, the first wire 92A and the third wire 92C are wound around the second wire 92B on different sides of the first pulley row 68A.

[0061] Here, we consider applying equation (2) to the first joint 70A. As described above, the wire 92 is wound around the first pulley 60A1 and the third pulley 60A3 from the upper side in Figure 3, and the wire 92 is wound around the second pulley 60A2 from the lower side in Figure 3. Therefore, when the first motor 90A winds the first wire 92A, the first pulley 60A1 rotates clockwise in the diagram; when the second motor 90B winds the second wire 92B, the second pulley 60A2 rotates counterclockwise in the diagram; and when the third motor 90C winds the third wire 92C, the third pulley 60A3 rotates clockwise in the diagram. In other words, in the first pulley row 68A, the difference in the number of pulleys 60 that rotate the first joint 70A clockwise and the number of pulleys 60 that rotate the first joint 70A counterclockwise is 1.

[0062] Therefore, if the torque applied to the first pulley row 68A by the first pulley 60A1 and the third pulley 60A3 is greater than the rotational torque applied by the second pulley 60A2, the first joint 70A rotates clockwise, as shown in Figure 5. Similarly, if the torque applied to the first pulley row 68A by the second pulley 60A2 is greater than the rotational torque applied by the first pulley 60A1 and the third pulley 60A3, the first joint 70A rotates counterclockwise, as shown in Figure 5. Note that if the torque applied by the first pulley 60A1 and the third pulley 60A3 is equal to the torque applied to the first pulley row 68A by the second pulley 60A2, the first joint 70A does not rotate and remains in the same position, as shown in Figure 3.

[0063] Furthermore, as described above, the second pulley 60A2 of the first pulley row 68A has twice the radius of the first pulley 60A1 and the third pulley 60A3. Therefore, as shown in equation (1), when tension is applied to the second wire 92B, the second pulley 60A2 applies twice the torque to the first pulley row 68A compared to the first pulley 60A1 and the third pulley 60A3.

[0064] Therefore, if the sum of the tensions on the first wire 92A and the third wire 92C is greater than twice the tension on the second wire 92B, the first joint 70A rotates clockwise, as shown in Figure 5. Also, if twice the tension on the second wire 92B is greater than the sum of the tensions on the first wire 92A and the third wire 92C, the first joint 70A rotates counterclockwise, as shown in Figure 5. Furthermore, if the sum of the tensions on the first wire 92A and the third wire 92C is equal to twice the tension on the second wire 92B, the first joint 70A does not rotate and remains in the same position, as shown in Figure 3.

[0065] Therefore, if the tension on the first wire 92A is increased to be greater than the tension on the second wire 92B while maintaining the sum of the tensions on the first wire 92A and the third wire 92C, the second joint 70B will rotate counterclockwise, as described above (see Figure 4). In other words, in this embodiment, by increasing the tension on the first wire 92A and decreasing the tension on the third wire 92C, only the second joint 70B can be rotated counterclockwise. To rotate the second joint 70B clockwise, the increase or decrease in the tensions on the first wire 92A and the third wire 92C should be reversed.

[0066] As mentioned above, if any of the wires 92 falls below the reserve tension, the wires 92 will slacken relative to the pulley 60. For example, consider the case where increasing the tension on the first wire 92A and decreasing the tension on the third wire 92C causes the tension of the third wire 92C to fall below the reserve tension. In such a case, by increasing the tensions of the first wire 92A and the second wire 92B while maintaining the tension of the third wire 92C, the tension of the third wire 92C can be reduced relatively compared to the first wire 92A and the second wire 92B, thereby allowing all wires 92 to exceed the reserve tension.

[0067] Furthermore, in this embodiment, as shown in Figure 6, the first joint 70A and the second joint 70B can also be rotated simultaneously. For example, if the sum of the tension on the first wire 92A and the tension on the third wire 92C is greater than twice the tension on the second wire 92B, and the tension on the second wire 92B is greater than the tension on the first wire 92A, then both the first joint 70A and the second joint 70B will rotate clockwise. Also, as an example, if the sum of the tension on the first wire 92A and the tension on the third wire 92C is greater than twice the tension on the second wire 92B, and the tension on the first wire 92A is greater than the tension on the second wire 92B, then the first joint 70A will rotate clockwise and the second joint 70B will rotate counterclockwise.

[0068] Therefore, the formula for controlling the torque of each joint 70 of the robot hand 10 in this embodiment is expressed by the following formula (3).

[0069]

number

[0070] In equation (3), N1 is the torque applied to the first joint 70A, and N2 is the torque applied to the first joint 70A. Also, T1 is the tension applied to the first wire 92A, T2 is the tension applied to the second wire 92B, and T3 is the tension applied to the third wire 92C. 1,1 This is the radius of the first pulley 60A1 at the first joint 70A, and R 1,2 This is the radius of the second pulley 60A2 of the first joint 70A, and R 1,3 This is the radius of the third pulley 60A3 at the first joint 70A. Also, R 2,1 This is the radius of the first pulley 60B1 of the second joint 70B, and R 2,2 This is the radius of the second pulley 60B2 of the second joint 70B. Note that R is in equation (3). 2,3 It is not listed, but this is because the second joint 70B does not have a third pulley 60. If it were to be listed, R 2,3 It is 0.

[0071] In this embodiment, for each pulley row 68 corresponding to each joint 70, the sum of the radii of the pulleys 60 that rotate clockwise is equal to the sum of the radii of the pulleys 60 that rotate counterclockwise. In other words, in this embodiment, the sum of the radii of the pulleys 60 in equation (3) is set to 0 for each row.

[0072] By the way, in a robot hand 10 having joints 70 where the sum of each row is not set to 0, there may be insufficient torque to drive a particular joint 70. Specifically, in an N+1 type wire-driven robot hand with multiple joints arranged in series, if the balance of the pulley row 68 that generates the torque to rotate each joint 70 is not maintained, extra motor power will be required to rotate each joint 70.

[0073] For example, consider a case where a pulley row 68 provided at a particular joint 70 includes a large pulley 60 and a small pulley 60. In this case, the power of the motor 90 that applies tension to the wire 92 wound around the large pulley 60 is less than the power of the motor 90 that applies tension to the wire 92 wound around the small pulley 60. In other words, the motor 90 that applies tension to the wire 92 wound around the small pulley 60 in order to keep the joint 70 stationary requires a larger torque than the motor 90 that applies tension to the wire 92 wound around the large pulley 60. As a result, there may be insufficient power supplied to joints 70 other than the joint 70 in question.

[0074] Furthermore, the specific joints 70 mentioned above include, in particular, the first joint 70A that connects the base 20 to the first link 40A connected to the base 20, and the second joint 70B that connects the first joint 70A to the first joint 70A. The first joint 70A and the second joint 70B are necessary because, in a multi-joint drive structure in which the links 40 are connected in a chain, it is necessary to increase the pre-tension required to ensure the rigidity of the joints 70.

[0075] Furthermore, as shown in equation (3) above, in order to set the tension of each wire 92, the torque of the motor 90 to which each wire 92 is connected is controlled. In this embodiment, each of the motors 90 is a multiple identical DC motor whose torque is controlled by a controller (not shown). That is, in this embodiment, by winding the wire 92 with the same torque in each motor 90, the same tension is generated.

[0076] Next, the operation and effects of this embodiment will be explained.

[0077] (Mechanism of Action and Effects) In the robot hand 10 according to this embodiment, the pulley rows 68 corresponding to the first joint 70A and the second joint 70B have the same sum of radii for the pulleys 60 that rotate the joint 70 counterclockwise as the sum of radii for the pulleys 60 that rotate the joint 70 clockwise. Therefore, in the robot hand 10 according to this embodiment, the rotation of the first joint 70A and the second joint 70B comes to a standstill when the tension applied to the wires 92 that rotate the first joint 70A and the second joint 70B by the respective motors 90 is equal. Here, since the first joint 70A and the second joint 70B are on the support end side (base 20 side) of the robot hand 10, which is made up of multiple links 40, the torque required to rotate them tends to be large. In other words, in the robot hand 10 according to this embodiment, the power of the motors 90 required to stop the rotation of the first joint 70A and the second joint 70B, which are specific joints 70 that require a large motor torque to control rotation, can be reduced.

[0078] In the robot hand 10 according to this embodiment, the sum of the radii of the pulleys 60 that rotate counterclockwise is equal to the sum of the radii of the pulleys 60 that rotate clockwise in all the pulley rows 68. Therefore, in the robot hand 10 according to this embodiment, the rotation of each joint 70 comes to a standstill when the tension applied to the wires 92 that rotate each joint 70 by each motor 90 is equal. In other words, in the robot hand 10 according to this embodiment, the power of the motors 90 required to stop the rotation of all joints 70 can be reduced.

[0079] Furthermore, in the robot hand 10 according to this embodiment, the total number of wires 92 is one greater than the total number of joints 70. Therefore, with the robot hand 10 according to this embodiment, the drive control can be simplified compared to the case where the total number of wires 92 is two or more greater than the total number of joints 70.

[0080] Also, in the robotic hand 10 according to this aspect, the rated capacities of the plurality of motors 90 are all equal. Therefore, according to the robotic hand 10 according to this aspect, drive control can be simplified compared to the case where the rated capacities of the plurality of motors 90 are different.

[0081] Also, in the robotic hand 10 according to this aspect, the number of pulleys 60 included in at least one pulley row 68 is odd. Therefore, in the robotic hand 10 according to this aspect, the degree of freedom in design can be improved.

[0082] Also, in the robotic hand 10 according to this aspect, in the pulley row 68 having an odd number of pulleys 60, the difference between the number of pulleys 60 that rotate the joint 70 counterclockwise and the number of pulleys 60 that rotate the joint 70 clockwise is 1. Therefore, in the robotic hand 10 according to this aspect, the degree of freedom in design can be improved.

[0083] 〈Regarding the aspect with more joints 70〉 Here, in the above embodiment and from formula (1) to formula (3), the case where the number of joints 70 is 2 has been described. The generalized formula (4) is as follows.

[0084]

Number

[0085] In formula (4), N1 to N i is the torque applied to the first joint 70A to the i-th joint 70 (i is a positive integer). Also, T1 to T j is the tension applied to the first wire 92A to the j-th wire 92 (j is a positive integer greater than i). Also, R 1,1 to R i,j is the radius of the first pulley 60A1 of the first joint 70A to the j-th pulley 60 of the i-th joint 70. Also, R i,jThe coefficient ±1, as in equation (1), represents the direction of the torque applied to the pulley train 68. Specifically, a value of +1 is taken when the pulley 60 applies a clockwise torque to the pulley train 68, and a value of -1 is taken when the pulley 60 applies a counterclockwise torque to the pulley train 68.

[0086] Furthermore, the fact that the sum of the radii of the pulleys 60 rotated counterclockwise for all pulley rows 68 is equal to the sum of the radii of the pulleys 60 rotated clockwise is expressed by the following equation (5).

[0087]

number

[0088] In equations (4) and (5), if there is no pulley 60 in the pulley row 68 of any joint 70, the component is 0 (see the second row, third column of equation (3)).

[0089] An example of a robot hand that satisfies the above equations (4) and (5) will be described as a modified example of this embodiment with reference to Figure 7. In the description of the modified example, for configurations that differ in part from this embodiment, an apostrophe ('') is added to the end of the reference numerals indicating the configuration according to this embodiment. For example, robot hand 10' in the modified example corresponds to robot hand 10 of the first embodiment. The same applies to other configurations, and a detailed description of these configurations will be omitted.

[0090] <Variations> Figure 7 shows a schematic diagram of a modified robot hand 10' according to this embodiment.

[0091] (composition) As shown in Figure 7, the robot hand 10' according to this modified example is equipped with four joints 70, from the first joint 70A to the fourth joint 70D, and five wires 92, from the first wire 92A to the fifth wire 92E. Furthermore, the first joint 70A to the fourth joint 70D are each provided with the first pulley rows 68A to the fourth pulley rows 68D. In addition, each of the first wires 92A to the fifth wire 92E is connected to the first motor 90A to the fifth motor 90E at the base 20. Note that Figure 7 is a schematic diagram showing the winding method of the wires 92 and the pulley rows 68, and the axes of the joints 70 do not necessarily have to be parallel.

[0092] As shown in Figure 7, in this modified example, each pulley row 68 has one pulley 60 that provides torque for clockwise rotation. In other words, in this modified example, each pulley row 68 has all but one pulley 60 that provides torque for counterclockwise rotation. The pulleys 60 that provide torque for counterclockwise rotation all have the same radius in each joint row.

[0093] In this modified example, the first wire 92A and the second wire 92B are each attached to the fourth link 40D at one end. In other words, the fourth joint 70D is the joint 70 that rotates the link 40 furthest from the base 20, and the fourth pulley row 68D of the fourth joint 70D has one pulley 60 that rotates counterclockwise and one pulley 60 that rotates clockwise.

[0094] In this modified example, one end of the third wire 92C is attached to the third link 40C, the fourth wire 92D to the second link 40B, and the fifth wire 92E to the first link 40A. In other words, in this modified example, the pulley rows 68 corresponding to each joint 70 that rotates the multiple links 40 connected sequentially from the base 20 have one more winding member in each subsequent pulley row 68, starting from the pulley row 68 of the joint 70 that rotates the link 40 furthest from the base 20. Also in this modified example, each pulley 60 that applies torque to rotate in a clockwise direction has a wire 92 wound around it, the other end of which is attached to the link 40 that the joint 70 corresponding to that pulley 60 rotates relatively.

[0095] In this modified example, the size of the pulley 60 at each joint 70 satisfies equation (5). As mentioned above, the pulley 60 that provides torque for counterclockwise rotation has the same radius in each joint row. That is, the third pulley 60C3 (the pulley 60 that rotates clockwise) at the third joint 70C has twice the radius of the first pulley 60C1 and the second pulley 60C2 (the pulleys 60 that rotate counterclockwise). Also, the fourth pulley 60B4 (the pulley 60 that rotates clockwise) at the second joint 70B has three times the radius of the first pulley 60B1 to the third pulley 60B3 (the pulleys 60 that rotate counterclockwise). Also, the fifth pulley 60A5 (the pulley 60 that rotates clockwise) at the first joint 70A has four times the radius of the first pulley 60A1 to the fourth pulley 60A4 (the pulleys 60 that rotate counterclockwise).

[0096] The other components are the same as those in the first embodiment.

[0097] Furthermore, in this modified example, an example of the procedure for deriving the tension applied to each wire 92 in order to obtain the torque when each joint 70 is rotationally driven, and a control method, are as follows.

[0098] (1) For the first joint 70A, calculate the tension of the pulley 60 that applies torque in the direction of rotation (including when held = rotation amount is 0; the same applies hereafter). For example, when the first joint 70A is rotated clockwise, make four times the tension of the fifth wire 92E greater than the sum of the tensions of the first wire 92A to the fourth wire 92D. More specifically, either increase the tension of the fifth wire 92E, or uniformly decrease the tensions of the first wire 92A to the fourth wire 92D. Also, for example, when the first joint 70A is rotated counterclockwise, make four times the tension of the fifth wire 92E less than the sum of the tensions of the first wire 92A to the fourth wire 92D. More specifically, either decrease the tension of the fifth wire 92E, or uniformly increase the tensions of the first wire 92A to the fourth wire 92D. (2) For the second joint 70B, calculate the tension of the pulley 60 that applies torque in the direction of rotation. For example, when the second joint 70B is rotated clockwise, the tension of the fourth wire 92D should be three times greater than the sum of the tensions of the first wire 92A to the third wire 92C. More specifically, either increase the tension of the fourth wire 92D, or uniformly decrease the tensions of the first wire 92A to the third wire 92C. Also, for example, when the second joint 70B is rotated counterclockwise, the tension of the fourth wire 92D should be three times less than the sum of the tensions of the first wire 92A to the third wire 92C. More specifically, either decrease the tension of the fourth wire 92D, or uniformly increase the tensions of the first wire 92A to the third wire 92C. (3) For the third joint 70C, calculate the tension of the pulley 60 that applies torque in the direction of rotation. For example, rotate the third joint 70C clockwise, or make twice the tension of the third wire 92C greater than the sum of the tensions of the first wire 92A and the second wire 92B. More specifically, increase the tension of the third wire 92C, or uniformly decrease the tensions of the first wire 92A and the second wire 92B. Also, for example, rotate the third joint 70C counterclockwise, make twice the tension of the third wire 92C less than the sum of the tensions of the first wire 92A to the second wire 92B. More specifically, decrease the tension of the third wire 92C, or uniformly increase the tensions of the first wire 92A and the second wire 92B. (4) For the fourth joint 70D, calculate the tension of the pulley 60 that applies torque in the direction of rotation. For example, when the fourth joint 70D is rotated clockwise, the tension of the second wire 92B should be greater than the tension of the first wire 92A. More specifically, either increase the tension of the second wire 92B or decrease the tension of the first wire 92A. Also, for example, when the fourth joint 70D is rotated counterclockwise, the tension of the second wire 92B should be less than the tension of the first wire 92A. More specifically, either decrease the tension of the second wire 92B or increase the tension of the first wire 92A. (5) The tension of each wire 92 is uniformly increased or decreased so that the smallest tension among the tensions of each wire 92 derived in (1) to (4) above becomes the reserve tension. (6) The first motor 90A to the fifth motor 90E are controlled so that the tension of each wire 92 becomes the tension of each wire 92 derived in (5) above.

[0099] Next, we will explain the effects and benefits of this modified version.

[0100] (Mechanism of Action and Effects) When controlling each joint 70 of the robot hand 10, even if all the pulley rows 68 of each joint 70 satisfy equation (5), if there are pulleys 60 with the same winding pattern, it may be difficult to independently control the rotational torque of those pulley rows 68.

[0101] Specifically, if there are multiple pulleys 60 that apply rotational torque in the same direction, the amount of calculation required to rotate the joint 70 including those pulleys 60 increases. For example, consider the case where there are two pulleys 60 that apply torque to rotate the first joint 70A clockwise and three pulleys 60 that apply torque to rotate the first joint 70A. In this case, to calculate the rotational torque that rotates the first joint 70A, it is necessary to multiply the radius of each pulley from the first pulley 60A1 to the fifth pulley 60A5 by the tension of each wire 92 and then calculate the sum. Therefore, when rotating the first joint 70A in either a clockwise or counterclockwise direction, the amount of calculation increases because the tension of the wires 92 acting on the pulleys 60 that rotate in the same direction must be derived separately.

[0102] On the other hand, in the robot hand 10 according to this modified example, there is one pulley 60 that rotates clockwise. Therefore, torque can be calculated by comparing the tension between the wire 92 wound around the one clockwise rotating pulley 60 and the other wires 92. In other words, in the robot hand 10 according to this example, it is not necessary to calculate the tension between the wires 92 that are wound around the counterclockwise rotating pulley 60 at any of the joints 70. Accordingly, the robot hand 10 in this modified example makes it easier to control multiple joints 70 independently.

[0103] In this modified example, it is preferable that the radii of the pulleys 60 that rotate counterclockwise in each pulley row 68 are all equal. This is because it becomes easier to derive the tension applied to each wire 92 even at joints 70 that are further from the base 20 than the joint 70 having the pulley row 68.

[0104] In this modified example, the parts with the same configuration as in the first embodiment can obtain the same functions and effects as in the first embodiment.

[0105] Next, an example of a robot hand according to the second embodiment of this disclosure will be described with reference to Figures 8 to 12. In this description, for configurations corresponding to the first embodiment, the reference numeral 100 is added to the reference numeral indicating the configuration in the first embodiment. For example, the robot hand 110 in this embodiment corresponds to the robot hand 10 in the first embodiment. The same applies to other configurations, and a detailed description of these configurations will be omitted.

[0106] [Second Embodiment] (composition) Figures 8 and 9 show a robot hand 110 of a second embodiment, which is an example of the wire-driven articulated structure of the present disclosure. Figure 10 is an enlarged view showing the arrangement of the components of the second joint 170B of the robot hand 110 according to this embodiment. As shown in Figures 8 and 9, the robot hand 110 in this embodiment is an articulated structure driven by the tension of a wire 92. The robot hand 110 comprises a base 120, a first link 140A, a second link 140B and a third link 140C, a second joint 170B and a third joint 170C, and a cross-axis joint 161. Note that the wire 92 is not shown in Figure 8. In this embodiment, components similar to those in the first embodiment are denoted by the same reference numerals, and detailed descriptions are omitted.

[0107] As shown in Figures 8 and 9, in this embodiment, the first motor 90A to the fourth motor 90D are arranged on the base 120. A cross-axis joint 161 is provided on the first link 140A side of the base 120. In other words, the first link 140A is connected to the base 161 via the cross-axis joint 161. The cross-axis joint pulley row 162 of the cross-axis joint 161 is positioned opposite the pulley row 168 of the second joint 170B. The cross-axis joint 161 is an example of the "first joint" in this embodiment.

[0108] As shown in Figures 9 and 10, the cross-axis joint pulley row 162 consists of four pulleys 60, from the first pulley 166A1 to the fourth pulley 166A4, arranged in the direction of the rotation axis (in this embodiment, the direction of arrow Z). The axial direction of the cross-axis joint pulley row 162 is perpendicular to the axial direction of the second pulley row 168B of the second joint 170B, as shown in Figures 9 and 10. More specifically, as shown in Figures 9 and 10, when viewed from the direction of arrow X, the axial direction of the cross-axis joint pulley row 162 and the axial direction of the second pulley row 168B (in this embodiment, the direction of arrow Y) are perpendicular. In this description, "the axial directions are perpendicular to each other" includes cases where the two axes are in a torsional relationship when viewed from other directions (for example, the direction of arrow Y or arrow Z). The specific configuration of the cross-axis joint pulley row 162 will be described later.

[0109] In this embodiment, the second pulley row 168B of the second joint 170B consists of four pulleys 60, from the first pulley 160B1 to the fourth pulley 160B4. As shown in Figure 10, the direction of the rotational torque that each pulley 60 applies to the second pulley row 168B is as follows: The first pulley 160B1 and the fourth pulley 160B4 are pulleys 60 that apply torque to rotate in a counterclockwise direction. The second pulley 160B2 and the third pulley 160B3 are pulleys 60 that apply torque to rotate in a clockwise direction.

[0110] In the second pulley row 168B, the first wire 92A is wound around the first pulley 160B1 from the lower side of the drawing in Figures 9 and 10. Also, as shown in Figure 10, one end of the first wire 92A is secured to the first pulley 160B1. Although hidden from the drawing in Figures 9 and 10, the fourth wire 92D is similar to the first pulley 160B1 and the first wire 92A, and the fourth wire 92D, wound around the fourth pulley 160B4 from the lower side of the drawing in Figures 9 and 10, has one end secured to the fourth pulley 160B4.

[0111] In this embodiment, the first pulley 160B1 and the fourth pulley 160B4 are restricted from rotating relative to the second link 140B. More specifically, the first pulley 160B1 and the fourth pulley 160B4 are fixed to the second link 140B in a way that prevents them from rotating.

[0112] Furthermore, the second wire 92B is wound around the second pulley 160B2 in the second pulley row 168B from the top side in the diagrams shown in Figures 9 and 10. Similarly, the third wire 92C is wound around the third pulley 160B3 from the top side in the diagrams shown in Figures 9 and 10.

[0113] The first link 140A is a member that rotates relative to the base 120 by the cross-axis joint 161, which is the "first joint" of this embodiment. That is, the specific function of the first link 140A in this embodiment is the same as in the first embodiment. Also, the specific functions of the second link 140B, the third joint 170C, and the third link 140C are the same as in the first embodiment. Note that in this embodiment, the names of the wires 92 wound around the first pulley 60B1 and the second pulley 160B2 of the third joint 170C are different from those in the first embodiment, but this is for convenience due to the arrangement of the pulleys 60. That is, the second wire 92B is wound around the first pulley 60B1 and the third wire 92C is wound around the second pulley 60B2 in the third pulley row 168C, but the substantial function and effect are the same as in the first embodiment.

[0114] Furthermore, the first pulley 160B1 and the fourth pulley 160B4 are fixed to the second link 140B in a way that prevents them from rotating. Therefore, in this embodiment, it can be said that the first wire 92A and the fourth wire 92D are "attached to the second link at one end."

[0115] Furthermore, in this embodiment as well, the second pulley row 168B and the third pulley row 168C satisfy the above-described equations (4) and (5).

[0116] In this embodiment, the cross-axis joint pulley row 162 of the cross-axis joint 161 consists of four pulleys 60, from the first pulley 166A1 to the fourth pulley 166A4. As shown in Figure 10, the direction of the rotational torque that each pulley 60 applies to the second pulley row 168B is as follows: Viewed from the direction of arrow Z, the first pulley 166A1 and the fourth pulley 166A4 are pulleys 60 that apply torque to rotate in a counterclockwise direction. The second pulley 166A2 and the third pulley 166A3 are pulleys 60 that apply torque to rotate in a clockwise direction.

[0117] In other words, the first pulley 166A1 and the fourth pulley 166A4 are examples of the "first winding members" in the cross-axis joint pulley row 162. Similarly, the second pulley row 166A2 and the third pulley row 166A3 are examples of the "second winding members" in the cross-axis joint pulley row 162.

[0118] Furthermore, in this embodiment, the cross-axis joint pulley row 162 satisfies the above-described equations (4) and (5).

[0119] Furthermore, the second pulley row 168B and the cross-axis joint pulley row 162 will be described in detail with reference to Figures 11 and 12.

[0120] Figure 11 is a schematic diagram showing the configuration of the cross-axis joint pulley row 162 and the second pulley row 168B, and is a side view. Figure 12 is a schematic diagram showing the configuration of the cross-axis joint pulley row 162 and the second pulley row 168B, and is a top view.

[0121] As shown in Figures 11 and 12, for the second pulley row 168B, the first pulley 160B1 and the second pulley 160B2 are pulleys 60 with radius r1. Also, the third pulley 160B3 and the fourth pulley 160B4 are pulleys 60 with radius r2.

[0122] The second pulley 160B2 and the third pulley 160B3 are positioned at a distance of r3 from the axial center of the second pulley row 168B, respectively. The first pulley 160B1 and the fourth pulley 160B4 are positioned at a distance of r4 from the axial center of the second pulley row 168B, respectively.

[0123] In this embodiment, as shown in Figures 11 and 12, r4 is greater than r3, and r2 is greater than r1.

[0124] As shown in Figures 11 and 12, for the cross-axis joint pulley row 162, the first pulley 166A1 and the second pulley 166A2 are pulleys 60 with a radius of r4. The third pulley 166A3 and the fourth pulley 166A4 are pulleys 60 with a radius of r3.

[0125] The second pulley 166A2 and the third pulley 166A3 are positioned at a distance of r1 from the axial center of the cross-axis joint pulley row 162. The first pulley 166A1 and the fourth pulley 166A4 are positioned at a distance of r2 from the axial center of the cross-axis joint pulley row 162.

[0126] Therefore, as shown in Figures 10 to 12, the second pulley row 168B has an inner set consisting of a second pulley 160B2 with radius r1 and a third pulley 160B3 with radius r2, which are spaced r3 apart from each other from the axial center of the second pulley row 168B. The second pulley row 168B also has an outer set consisting of a first pulley 160B1 with radius r1 and a fourth pulley 160B4 with radius r2, which are spaced r4 apart from each other from the axial center of the second pulley row 168B.

[0127] Furthermore, the cross-axis joint pulley row 162 has an inner set consisting of a second pulley 166A2 with radius r4 and a third pulley 166A3 with radius r3, which are separated from each other by a length r1 from the axial center of the cross-axis joint pulley row 162. Furthermore, the cross-axis joint pulley row 162 has an outer set consisting of a first pulley 166A1 with radius r4 and a fourth pulley 166A4 with radius r3, which are separated from each other by a length r2 from the axial center of the cross-axis joint pulley row 162.

[0128] As shown in Figures 11 and 12, the axial center of the second pulley row 168B and the axial center of the intersecting joint pulley row 162 are aligned with each other in the X direction. In other words, in this embodiment, the axial center of the second pulley row 168B and the axial center of the intersecting joint pulley row 162 coincide when viewed from the direction of arrow X.

[0129] Thus, as shown in Figures 10 to 12, in this embodiment, the tangents of the pulleys 60 included in the second pulley row 168B all coincide with the tangents of the pulleys 60 included in the cross-axis joint pulley row 162. More specifically, as shown in Figures 10 to 12, the tangents of the pulleys 60 of the inner set in the second pulley row 168B and the inner set in the cross-axis joint pulley row 162 coincide. Also, as shown in Figures 10 to 12, the tangents of the pulleys 60 of the outer set in the second pulley row 168B and the outer set in the cross-axis joint pulley row 162 coincide. In other words, in this embodiment, the second pulley row 168B and the cross-axis joint pulley row 162 are examples of a "pair of winding member rows".

[0130] Next, the operation and effects of this embodiment will be described.

[0131] (Mechanism of Action and Effects) In this embodiment of the robot hand 110, there is a pair of pulley rows 168 whose rotational axis directions are perpendicular to each other, and the pulleys 60 included in the pair of pulley rows 168 have tangential directions that coincide with each other. Therefore, the wire 92 that spans the second pulley row 168B and the intersecting axis joint pulley row 162, which are the pair of pulley rows, coincides with the rotational direction of the pulleys 60, so the wire 92 does not move in the direction of the rotational axis of the pulleys 60.

[0132] In other words, in the robot hand 110 according to this embodiment, the wire 92 can be placed between the pulleys 60 without using other idlers 62. In addition, the robot hand 110 according to this embodiment can reduce the number of parts. Furthermore, the robot hand 110 according to this embodiment can suppress the enlargement of the cross-axis joint 161 portion.

[0133] In this embodiment as well, the parts with the same configuration as in the first embodiment can obtain the same functions and effects as in the first embodiment. That is, in this embodiment as well, the power of the motor 190 required to stop the rotation of a specific joint 170 that requires a large motor torque to control the rotation is reduced.

[0134] Next, a modified example of this embodiment will be described with reference to Figure 13. In the description of the modified example, for configurations that differ in part from this embodiment, an apostrophe ('') is added to the end of the reference numerals indicating the configuration according to this embodiment. For example, the cross-axis joint pulley row 162' in the modified example corresponds to the cross-axis joint pulley row 162 in this embodiment. The same applies to other configurations, and a detailed description of these configurations will be omitted.

[0135] <Variations> Figure 13 shows other configurations of the second pulley row 168B' and the cross-axis joint pulley row 162' in this embodiment.

[0136] As shown in Figure 13, in this embodiment, the pulleys 60 included in the second pulley row 168B' are arranged such that the winding radius decreases sequentially from both sides in the direction of the rotation axis toward the inside. Similarly, the pulleys 60 included in the intersecting joint pulley row 162' are arranged such that the winding radius decreases sequentially from both sides in the direction of the rotation axis toward the inside.

[0137] As shown in Figure 13, in this modified example as well, the tangents of the pulleys 60 included in the second pulley row 168B' all coincide with the tangents of the pulleys 60 included in the cross-axis joint pulley row 162'. In other words, in this embodiment, the second pulley row 168B' and the cross-axis joint pulley row 162' are examples of a "pair of winding member rows".

[0138] (Mechanism of Action and Effects) In this modified example, the number of pulleys 60 included in the second pulley row 168B' and the cross-axis joint pulley row 162' is not limited to four. That is, even in a robot hand 110 having orthogonal joints 170, the robot hand 110 having the pulley row 168 according to this modified example can satisfy the conditions of equations (4) and (5) in the pulley row 168.

[0139] In this modified example, the parts that have the same configuration as in the first or second embodiment can obtain the same functions and effects as in the first or second embodiment.

[0140] Furthermore, in this modified example, even when the number of pulleys 60 included in the pulley row 168 exceeds 4, the four innermost pulleys 60 can be arranged in the configuration of the second embodiment. In this case, it is sufficient that any of the four innermost pulleys 60 have a smaller diameter than the other pulleys 60.

[0141] Next, an example of a robot hand according to the third embodiment of this disclosure will be described with reference to Figures 14 and 15. In this description, for configurations corresponding to the first embodiment, the reference numeral 200 is added to the reference numeral indicating the configuration in the first embodiment. For example, the robot hand 210 in this embodiment corresponds to the robot hand 10 in the first embodiment. The same applies to other configurations, and a detailed description of these configurations will be omitted.

[0142] [Third Embodiment] (composition) Figures 14 and 15 show schematic diagrams of a robot hand 210 of a third embodiment, which is an example of the wire-driven articulated structure of the present disclosure.

[0143] As shown in Figures 14 and 15, the robot hand 210 in this embodiment is a multi-jointed structure driven by the tension of a wire 92. Note that the wire 92 is not shown in Figure 14. In this embodiment, components similar to those in the first or second embodiment are denoted by the same reference numerals, and detailed descriptions are omitted. Note that although the rotation axes of the joints are all drawn parallel to each other, this is a schematic diagram and they do not necessarily have to be parallel.

[0144] As shown in Figure 14, the robot hand 210 in this embodiment comprises two finger members 230, a wrist member to which the two finger members 230 are connected, and a base portion 222 to which the wrist member is connected. In this embodiment, the wrist member and the base portion 222 are examples of a "base portion 220". The two finger members 230 each have at least a first joint 270A, a first link 240A, a second joint 270B, and a second link 240B, and are rotatable relative to the wrist member via the first joint 270A.

[0145] In this embodiment, the first finger member 230A has four joints 270 from the first joint 270A to the fourth joint 270D, and four links 240 from the first link 240A to the fourth link 240D, as shown in Figure 14. The arrangement of the pulleys 60 and wires 92 in the first finger member 230A is the same as in the first embodiment or a modified version thereof. That is, the pulley row 268 of the first finger member 230A satisfies the above-described equations (4) and (5).

[0146] As shown in Figure 14, the second finger member 230B has three joints 270 from the first joint 270A to the third joint 270C, and three links 240 from the first link 240A to the third link 240C. The arrangement of the pulleys 60 and wires 92 in the second finger member 230B is the same as in the first embodiment or a modified version thereof. That is, the pulley row 268 of the second finger member 230B satisfies the above-described equations (4) and (5).

[0147] In this embodiment, as shown in Figure 14, the base portion 222 is equipped with multiple motors 90 for winding up the wires 92 that are wrapped around the multiple joints 270 in this embodiment.

[0148] Furthermore, in this embodiment, as shown in Figure 14, the wrist member has a first wrist joint 237A and a second wrist joint 237B, which are examples of base internal joints. The wrist member also has a first wrist link 250A and a second wrist link 250B. The first wrist link 250A is connected to the base portion 222 via the first wrist joint 237A. The second wrist link 250B is connected to the first wrist link 250A via the second wrist joint 237B. Multiple finger members 230 are connected to the second wrist link 250B.

[0149] The first wrist joint 237A and the second wrist joint 237B have pulley rows 236, similar to the first and second embodiments. In this embodiment, all the wires 92 that are wound around the multiple finger members 230 are wound around the pulley row 236A of the first wrist joint 237A and the pulley row 236B of the second wrist joint 237B. In other words, in this disclosure, "base 220" refers to a component that has pulley rows 236 around which all the wires 92 connected to the multiple finger members 230 are wound, and also where the motor 90 is located. In other words, in this disclosure, "base 220" refers to the component that has the configuration in which the motor 90 is located and the pulley row 236 around which all the wires 92 connected to the motor 90 are wound.

[0150] In this embodiment, the multiple motors 90 that drive the first finger member 230A, the multiple motors 90 that drive the second finger member 230B, and the multiple motors 90 that drive the wrist member may each have different specifications. That is, as long as the rated capacities of the multiple motors 90 connected to a single first link 240A are the same, the rated capacities of the motors 90 that drive each finger member 230 or wrist member may be different. Even in this case, the drive control when driving each finger member 230 is simpler than when the rated capacities of the multiple motors 90 connected to the first link 240A are different.

[0151] Here, Figure 15 shows how the wires 92 are wound around each of the pulley rows 236B of the second wrist joint 237B in this embodiment. As shown in Figure 15, the pulley row 236B of the second wrist joint 237B has a first pulley group 261A, a second pulley group 261B, a third pulley group 261C, and a fourth pulley group 261D.

[0152] The first pulley group 261A is a pulley 60 that applies torque to rotate the second wrist joint 237B clockwise. As shown in Figure 15, the first pulley group 261A consists of one pulley 60 in this embodiment, but the number of pulleys 60 in the first pulley group 261A is not particularly limited.

[0153] The second pulley group 261B is a pulley 60 that applies torque to rotate the second wrist joint 237B counterclockwise. As shown in Figure 15, the second pulley group 261B consists of one pulley 60 in this embodiment, but the number of pulleys 60 in the second pulley group 261B is not particularly limited.

[0154] The third pulley group 261C is a pulley 60 that applies torque to rotate the second wrist joint 237B clockwise. Five wires 92 connected to the first finger member 230A are also attached to the third pulley group 261C. In this embodiment, the third pulley group 261C consists of five pulleys 60, but the number of pulleys 60 in the third pulley group 261C is not particularly limited.

[0155] The fourth pulley group 261D is a pulley 60 that applies torque to rotate the second wrist joint 237B counterclockwise. Four wires 92 connected to the second finger member 230B are also attached to the fourth pulley group 261D. In this embodiment, the fourth pulley group 261D consists of four pulleys 60, but the number of pulleys 60 in the fourth pulley group 261D is not particularly limited.

[0156] In this embodiment, in the pulley array 236B of the second wrist joint 237B, the first pulley group 261A and the third pulley group 261C provide torque that rotates the second wrist joint 237B clockwise. Similarly, the second pulley group 261B and the fourth pulley group 261D provide torque that rotates the second wrist joint 237B counterclockwise. That is, in the pulley array 236B of the second wrist joint 237B in this embodiment, the pulley 60 that provides counterclockwise rotation torque has a wire 92 wound around it that connects to the first link 240A of the second finger member 230B, which is half of the multiple first links 240A. Also, in the pulley array 236 of the second wrist joint 237B in this embodiment, the pulley 60 that provides clockwise rotation torque has a wire 92 wound around it that connects to the first link 240A of the first finger member 230A, which is the remaining half of the multiple first links 240A.

[0157] In this embodiment, it is preferable that the sum of the winding radii of the pulleys 60 of the first pulley group 261A and the third pulley group 261C is equal to the sum of the winding radii of the pulleys 60 of the second pulley group 261B and the fourth pulley group 261D.

[0158] In this embodiment, it is more preferable that the sum of the winding radii of the pulleys 60 of the first pulley group 261A is equal to the sum of the winding radii of the second pulley group 261B. That is, it is more preferable that the sum of the winding radii of the pulleys 60 of the third pulley group 261C is equal to the sum of the winding radii of the pulleys 60 of the fourth pulley group 261D. This is because, when the rotational torque generated by the third pulley group 261C is equal to the rotational torque generated by the fourth pulley group 261D, the rotational direction of the second wrist joint 237B can be controlled by controlling the rotational torque generated by the first pulley group 261A and the second pulley group 261B.

[0159] Furthermore, the pulley row 236A of the first wrist joint 237A is the same as the pulley row 236B of the second wrist joint 237B. That is, the pulley row 236A of the first wrist joint 237A has at least one more pulley 60 in the first pulley group 261A or the second pulley group 262B than the pulley row 236B of the second wrist joint 237B. And, in the pulley row 236A of the first wrist joint 237A, it is preferable that the sum of the winding radii of the pulleys 60 in the first pulley group 261A is equal to the sum of the winding radii of the pulleys 60 in the second pulley group 261B.

[0160] Furthermore, in this embodiment as well, the pulley row 236 of the first wrist joint 237A and the pulley row 236 of the second wrist joint 237B satisfy the above-described equations (4) and (5).

[0161] Next, the operation and effects of this embodiment will be described.

[0162] (Mechanism of Action and Effects) In this embodiment, the robot hand 210 has a base 220 and a plurality of first links 240A and a plurality of second links 240B that rotate relative to the plurality of first links 240A. In other words, according to this embodiment, a robot hand 210 is obtained in which a plurality of components are driven relative to the base 220.

[0163] In this embodiment of the robot hand 210, the base 220 has a wrist joint 237, so the base 220 can be rotated and deformed. Therefore, according to this embodiment of the robot hand 210, the positions of multiple first links 240A and second links 240B can be controlled by controlling the rotation of the wrist joint 237.

[0164] According to this embodiment of the robot hand 210, in a robot hand 210 where the total number of first links 240A is even, the drive control of the wrist joint 237 can be simplified.

[0165] In this embodiment as well, the parts configured in the same way as in the first or second embodiment can obtain the same functions and effects as in the first or second embodiment.

[0166] Next, modifications of this embodiment will be described with reference to Figures 16 and 17. In the description of modifications, for configurations that differ in part from this embodiment, an apostrophe ('') is added to the end of the reference numerals indicating the configurations according to this embodiment. For example, the wrist joint 237' in the modifications corresponds to the wrist joint 237 in this embodiment. The same applies to other configurations, and a detailed description of these configurations will be omitted.

[0167] <Variations> Figures 16 and 17 show schematic diagrams of a modified robot hand 210 of the third embodiment, which is an example of the wire-driven articulated structure of the present disclosure. In this modified example, components similar to those in the first to third embodiments are denoted by the same reference numerals, and detailed descriptions are omitted.

[0168] As shown in Figure 16, the robot hand 210' in this embodiment includes three finger members 230, a wrist member to which each of the finger members 230 is connected, and a base portion 222 to which the wrist member is connected. In other words, this modified version has a third finger member 230C in addition to the robot hand 210' according to the third embodiment.

[0169] In this embodiment, the third finger member 230C has three joints 270 from the first joint 270A to the third joint 270C, and three links 240 from the first link 240A to the third link 240C, as shown in Figure 16. The arrangement of the pulleys 60 and wires 92 in the third finger member 230C is the same as in the first embodiment or a modified version thereof. That is, the pulley row 268 of the third finger member 230C satisfies the above-described equations (4) and (5). In addition, a total of four wires 92 are attached to the first pulley row 268A at the first joint 270A of the third finger member 230C, as shown in Figure 16.

[0170] Here, Figure 17 shows how the wires 92 are wound around each of the pulley rows 236' of the second wrist joint 237B' in this embodiment. As shown in Figure 17, the pulley row 236' of the second wrist joint 237B' has a first pulley group 261A, a second pulley group 261B, a third pulley group 261C, a fourth pulley group 261D, a fifth pulley group 261E, and a sixth pulley group 261F. The configuration of the first pulley group 261A to the fourth pulley group 261D is the same as in the third embodiment.

[0171] The fifth pulley group 261E is a pulley 60 that applies torque to rotate the second wrist joint 237B' clockwise. Furthermore, two of the four wires 92 connected to the third finger member 230C are connected to the fifth pulley group 261E. In other words, at least one of the multiple wires 92 connected to the third finger member 230C is connected to the fifth pulley group 261E.

[0172] The sixth pulley group 261F is a pulley 60 that applies torque to rotate the second wrist joint 237B counterclockwise. Furthermore, two of the four wires 92 connected to the third finger member 230C are attached to the sixth pulley group 261F. In other words, the remaining wires 92 that were not attached to the fifth pulley group 261E are attached to the sixth pulley group 261F.

[0173] Thus, in the pulley array 236' of the second wrist joint 237B' in this embodiment, the first pulley group 261A, the third pulley group 261C, and the fifth pulley group 261E provide torque that rotates the second wrist joint 237B clockwise. Similarly, the second pulley group 261B, the fourth pulley group 261D, and the sixth pulley group 261F provide torque that rotates the second wrist joint 237B' counterclockwise. In other words, in the pulley array 236' of the second wrist joint 237B' in this embodiment, half of the total number of even-numbered wires 92 connected to the first link 240A of the third finger member 230C are wound around the pulley 60 that provides counterclockwise rotation torque, in addition to those in the third embodiment. Furthermore, in this embodiment, among the pulley row 236 of the second wrist joint 237B', the pulley 60 that applies rotational torque in the clockwise direction has, in addition to what is present in the third embodiment, the remaining half of the total number of even wires 92 connected to the first link 240A of the third finger member 230C wound around it. In other words, in this modified example, among the multiple finger members 230, the multiple wires 92 connected to any one of the finger members 230 are distributed equally between the fifth pulley group 261E and the sixth pulley group 261F.

[0174] In this modified example, it is preferable that the sum of the winding radii of the pulleys 60 of the first pulley group 261A, the third pulley group 261C, and the fifth pulley group 216E is equal to the sum of the winding radii of the pulleys 60 of the second pulley group 261B, the fourth pulley group 261D, and the sixth pulley group 216F.

[0175] Furthermore, in this modified example, it is more preferable that the sum of the winding radii of the pulleys 60 in the first pulley group 261A is equal to the sum of the winding radii of the pulleys 60 in the second pulley group 261B. That is, it is more preferable that the sum of the winding radii of the pulleys 60 in the third pulley group 261C and the pulleys 60 in the fifth pulley group 261E is equal to the sum of the winding radii of the pulleys 60 in the fourth pulley group 261D and the sixth pulley group 261F.

[0176] Furthermore, it is even more preferable that the sum of the winding radii of the pulleys 60 in the third pulley group 261C is equal to the sum of the winding radii of the pulleys 60 in the fourth pulley group 261D. That is, it is even more preferable that the sum of the winding radii of the pulleys 60 in the fifth pulley group 261E is equal to the sum of the winding radii of the pulleys 60 in the sixth pulley group 261F.

[0177] In this modified example, as described above, the wires 92 wound around the fifth pulley group 261E and the sixth pulley group 261F are both connected to the third finger member 230C. In this modified example, the first link 240A of the third finger member 230C is an example of a "specific link".

[0178] Furthermore, the pulley row 236A of the first wrist joint 237A' is the same as the pulley row 236B' of the second wrist joint 237B'. That is, the pulley row 236A of the first wrist joint 237A' has at least one more pulley 60 in the first pulley group 261A or the second pulley group 262B than the pulley row 236B' of the second wrist joint 237B'. And, in the pulley row 236A' of the first wrist joint 237A, it is preferable that the sum of the winding radii of the pulleys 60 in the first pulley group 261A is equal to the sum of the winding radii of the pulleys 60 in the second pulley group 261B.

[0179] Furthermore, in this embodiment as well, the pulley row 236 of the first wrist joint 237A' and the pulley row 236 of the second wrist joint 237B' satisfy the above-described equations (4) and (5).

[0180] Next, the operation and effects of this embodiment will be described.

[0181] (Mechanism of Action and Effects) According to this embodiment of the robot hand 210', the drive control of the wrist joint 237 can be simplified in a robot hand 210' in which the total number of first links 240A is odd.

[0182] In this embodiment as well, the parts configured in the same way as in the first to third embodiments and their modified versions can obtain the same functions and effects as in the first to third embodiments and their modified versions.

[0183] <Other variations> In the above-described modification, the number of wires 92 connected to the first link 240A of the third finger member 230C was four. The robot hand 210' in this modification is not limited to this, and for example, the number of wires 92 connected to the third finger member 230C may be odd. In this case as well, at least one wire 92 is wound around the pulley 60 of the fifth pulley group 261E, and the remaining wires 92 are wound around the pulley 60 of the sixth pulley group 261F. By making the sum of the winding radii of the pulleys 60 of the fifth pulley group 261E equal to the sum of the winding radii of the pulleys 60 of the sixth pulley group 261F, the same operation and effect as in the above-described modification can be obtained.

[0184] [Other embodiments] In the above explanation, it was assumed that in all pulley rows, the sum of the radii of the clockwise-rotating pulleys and the sum of the radii of the counterclockwise-rotating pulleys were equal. The robot hand according to this disclosure is not limited to this, and it is sufficient that in at least the first and second pulley rows, the sum of the radii of the clockwise-rotating pulleys and the sum of the radii of the counterclockwise-rotating pulleys are equal. For example, in the third pulley row, the sum of the radii of the clockwise-rotating pulleys and the sum of the radii of the counterclockwise-rotating pulleys do not have to be equal.

[0185] Furthermore, while the above description assumed that all motors had the same rating, the robot hand relating to this disclosure is not limited to this. In other words, the robot hand relating to this disclosure may have motors with different ratings.

[0186] Furthermore, while all motors described above were assumed to be DC motors whose torque is controlled by a controller (not shown), the robot hand according to this disclosure is not limited to this. For example, an AC motor may be used instead of a DC motor, or a stepping motor, servo motor, etc., may be used to control the amount of rotation. Moreover, instead of controlling the torque or amount of rotation of the motor, the tension of each wire may be detected by a tension sensor, and the motor may be controlled so that the tension of each wire reaches a target value.

[0187] Furthermore, although a pulley was used as an example of a winding member in the above description, the robot hand according to this disclosure is not limited to this. That is, any configuration that can generate rotational torque by winding a wire may be used, such as a rolling member without a shaft, or a sliding member such as a simple pin.

[0188] These modified examples also yield the same effects and benefits as described above.

[0189] Furthermore, while the above description described a robot hand as an example of a wire-driven articulated structure relating to this disclosure, the applications of the wire-driven articulated structure relating to this disclosure are not limited to this. In other words, it is understood that the technology relating to this disclosure can be applied to any structure having multiple joints that deforms by wire drive.

[0190] While embodiments of this disclosure have been described above with reference to the attached drawings, it is clear that any person with ordinary skill in the art to which this disclosure belongs could conceive of various modifications or applications within the scope of the technical idea described in the claims, and these too are naturally understood to fall within the technical scope of this disclosure. [Explanation of Symbols]

[0191] 10. Robot Hand (An example of a wire-driven multi-joint structure) 20 base 22 Base 40 links 60 Pulley (an example of a winding member) 62 Idler 68. Pulley row (an example of a winding member row) 70 joints 90 motor 92 wires 161 Cross-axis joint (an example of the first joint) 162 Cross-axis joint pulley row 166 Pulley 236 Base pulley row (an example of a base internal winding member row) 237 Wrist joint (an example of a basal internal joint) 250 Wrist link (an example of a base internal link)

Claims

1. The base and, A plurality of links, each having a first link connected to the base and rotating relative to the base via a first joint, and a second link connected to the first link and rotating relative to the first link via a second joint, Distributed in the base are a plurality of motors, the number of which exceeds the total number of joints and is less than twice the total number of joints, A plurality of wires, one end of which is attached to each of the plurality of motors and the other end of which is attached to one of the links included in the plurality of links, A row of winding members having multiple winding members aligned along the rotation axis of the multiple joints, Equipped with, One or more of the winding members included in the winding member row corresponding to the first joint and the second joint have a different winding radius from the other winding members. The winding member rows corresponding to the first joint and the second joint are such that the sum of the winding radii of the first winding members that rotate the joint in the first direction when pulled by the motor is equal to the sum of the winding radii of the second winding members that rotate the joint in the second direction when pulled by the motor. Wire-driven articulated structure.

2. In the plurality of winding member rows, at all joints including the first joint and the second joint, the sum of the winding radii of the first winding member is equal to the sum of the winding radii of the second winding member. A wire-driven articulated structure according to claim 1.

3. The total number of wires is one greater than the total number of joints. A wire-driven articulated structure according to claim 1.

4. The base has a plurality of first links connected to each of the plurality of first joints, and a plurality of second links that rotate relative to the plurality of first links via a plurality of second joints. The wire-driven articulated structure according to claim 2.

5. The base has a plurality of internal links and an internal joint that rotates the plurality of internal links relative to each other. The base internal joint has a row of base internal winding members around which all the wires that are wrapped around the plurality of first joints are wound. A wire-driven articulated structure according to claim 4.

6. The total number of the aforementioned first links is even. A wire is wound around the first winding member of the winding member row corresponding to the base internal joint, which is connected to half of the first links in the plurality of first links. The second winding member of the winding member row corresponding to the base internal joint has a wire wound around it that connects to the remaining half of the first links in the plurality of first links. The sum of the winding radii of the first winding member having the base internal joint is equal to the sum of the winding radii of the second winding member. A wire-driven articulated structure according to claim 5.

7. The total number of the aforementioned first links is odd. The first winding member of the winding member row corresponding to the base internal joint has at least one wire connected to a specific link included in the first link and wires connected to half of the first links in the plurality of first links excluding the specific link wound around it. The second winding member of the winding member row corresponding to the base internal joint has the remaining wires connected to the specific link and the remaining half of the first links in the plurality of first links excluding the specific link wound around it. The sum of the winding radii of the first winding member having the base internal joint is equal to the sum of the winding radii of the second winding member. A wire-driven articulated structure according to claim 5.

8. The aforementioned multiple motors all have the same rated capacity. A wire-driven articulated structure according to claim 1.

9. It has a pair of winding member rows whose rotational axis directions are perpendicular to each other, The tangents of the winding members included in one of the pair of winding member rows coincide with the tangents of the winding members included in the other of the pair of winding member rows. A wire-driven articulated structure according to claim 1.

10. The pair of winding member rows are arranged such that the winding radius decreases sequentially from both sides in the direction of the rotation axis toward the inside. A wire-driven articulated structure according to claim 9.

11. The aforementioned row of winding members consists of a first winding member with radius r1 and a second winding member with radius r2, separated by a length r3 from the center of the row of winding members, and a second winding member with radius r2 and a second winding member with radius r1, separated by a length r4 from the center of the row of winding members. The other row of winding members consists of a first winding member with radius r3 and a second winding member with radius r4, separated by a length r1 from the center of the other row of winding members, and a second winding member with radius r4 and a second winding member with radius r3, separated by a length r2 from the center of the other row of winding members. A wire-driven articulated structure according to claim 9.

12. The number of wrapping members in at least one wrapping member row is odd. A wire-driven articulated structure according to any one of claims 1 to 9.

13. A winding member row having an odd number of winding members is one in which the difference between the number of winding members that rotate the joint in the first direction and the number of winding members that rotate the joint in the second direction is 1. The wire-driven articulated structure according to claim 12.

14. The row of winding members corresponding to the joint that rotates the link furthest from the base among the multiple links connected sequentially from the base comprises one first winding member and one second winding member. Each joint that rotates the multiple links connected sequentially from the base and the corresponding row of winding members has one more winding member in each row, starting from the row of winding members that rotates the link furthest from the base, and the number of winding members in either the first winding member or the second winding member in that row of winding members is 1. In each of the aforementioned winding members, a wire is wound around which the other end is secured to a link that rotates relatively between the winding member and the corresponding joint. The wire-driven articulated structure according to claim 3.

Images