Joint devices, robotic hand devices
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- NEC PLATFROMS LTD
- Filing Date
- 2024-03-15
- Publication Date
- 2026-08-04
AI Technical Summary
【0008】 上記本開示によれば、ワイヤー牽引駆動方式の関節装置において、1関節で2自由度の回転動作を再現することができる。
Smart Images
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Abstract
Description
Technical Field
[0001] The present disclosure relates to an articulation device and a robot hand device.
Background Art
[0002] Patent Document 1 below discloses a robot hand and a robot including the same. This robot hand includes a base part, a plurality of finger structures coupled to the base part, a drive part for driving the plurality of finger structures, and a wire for transmitting a driving force from the drive part to the plurality of finger structures.
Prior Art Document
Patent Document
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] In the wire traction drive method as described above, it is possible to perform a single-degree-of-freedom operation such as a bending and stretching operation or a rotational operation on one mechanism. However, when traction is applied from multiple directions, the mechanism may not be able to move in the intended direction. Therefore, in the wire traction drive method, an operation with a degree of freedom of one or more has not been reproduced at a single joint. Therefore, in conventional robot hand devices, the structure is often a combination of two or more mechanisms that perform a single-degree-of-freedom operation, resulting in a larger size of the device.
[0005] An object of the present disclosure is to provide an articulation device and a robot hand device that solve the above problems.
Means for Solving the Problems
[0006] In order to solve the above problems, the present disclosure proposes the following means. The joint device according to this disclosure comprises a base portion, a movable portion that is movable relative to the base portion, a spherical bearing having an inner ring fixed to the base portion side and an outer ring fixed to the movable portion side, a wire pulling device that pulls a wire connected to the outer ring side and rotates the outer ring around two of the rotation axes, the roll axis, and the yaw axis, and a rotation restricting portion that restricts the rotation of the outer ring around the remaining rotation axis, which is not one of the two rotation axes.
[0007] Furthermore, the robot hand device according to this disclosure comprises a hand body, finger parts that are movable relative to the hand body, and the joint device that connects the hand body and the finger parts. [Effects of the Invention]
[0008] According to the above disclosure, a wire-traction driven joint device can reproduce rotational motion with two degrees of freedom in one joint. [Brief explanation of the drawing]
[0009] [Figure 1] This is a diagram showing the configuration of a joint device according to the minimum configuration example of this disclosure. [Figure 2] This is a diagram showing the configuration of a joint device according to one embodiment of the present disclosure. [Figure 3] This is an exploded perspective view of the peripheral structure of a spherical bearing according to one embodiment of the present disclosure. [Figure 4] This is a perspective view of a joint device according to one embodiment of the present disclosure, as seen from the connection side. [Figure 5] This is a perspective view showing the connection state between the first wire attachment part and the wire pulling device according to one embodiment of the present disclosure. [Figure 6] This is a perspective view showing the connection between a second wire attachment portion and a wire pulling device according to one embodiment of the present disclosure. [Figure 7] This figure shows the radial abduction and ulnar adduction of a movable part according to one embodiment of the present disclosure. [Figure 8] This figure shows the palmar abduction and palmar adduction of a movable part according to one embodiment of the present disclosure. [Modes for carrying out the invention]
[0010] A minimum configuration example of this disclosure will be described with reference to Figure 1. Figure 1 is a diagram showing the configuration of the joint device 1 according to the minimum configuration example of this disclosure. As shown in Figure 1, the joint device 1 comprises a base portion 10, a movable portion 20, a spherical bearing 30, a wire traction device 40, and a rotation restricting portion 53.
[0011] The base portion 10 is, for example, the hand body of a robot hand device, but is not limited to the hand body. The movable portion 20 is, for example, a finger part of a robot hand device, but is not limited to the finger part. The spherical bearing 30 has an inner ring 31 fixed to the base portion 10 side and an outer ring 32 fixed to the movable portion 20 side.
[0012] The outer ring 32 is rotatable around the roll axis (X-axis), pitch axis (Y-axis), and yaw axis (Z-axis). The roll axis (X-axis), pitch axis (Y-axis), and yaw axis (Z-axis) are orthogonal to each other, and their intersection is set as the rotation center of the spherical bearing 30. The wire traction device 40 rotates the outer ring 32 around two of the three rotation axes: the pitch axis (Y-axis) and the yaw axis (Z-axis).
[0013] The rotation restricting unit 53 restricts the rotation of the outer ring 32 around the roll axis (X axis), which is the remaining rotation axis other than the pitch axis (Y axis) and yaw axis (Z axis). This allows for independent control of the rotational motion of the two degrees of freedom (rotational motion around the two rotation axes, the pitch axis (Y axis) and the yaw axis (Z axis)), and even if the outer ring 32 is pulled in multiple directions by the wire traction device 40, it can be rotated in the intended direction.
[0014] Thus, according to the above-described joint device 1, by combining the spherical bearing 30, the wire traction device 40, and the rotation restricting portion 53, a rotational movement with two degrees of freedom can be reproduced with one joint. Further, according to the robot hand device provided with the joint device 1, with a small configuration, the movement of the finger parts can be made closer to the movement of a human hand.
[0015] Next, in addition to FIG. 1, an embodiment of the present disclosure will be described with reference to FIGS. 2 to 7. In FIGS. 2 to 7, the same reference numerals are given to the configurations common to FIG. 1 to simplify the description.
[0016] FIG. 2 is a configuration diagram of the joint device 1 according to an embodiment of the present disclosure. In FIG. 2, the wires of the wire traction device 40 are not shown for improved visibility. The same applies to FIGS. 4, 7, and 8 described later. As shown in FIG. 2, the joint device 1 is provided in a robot hand device. The robot hand device includes a hand body and finger parts that are movable with respect to the hand body.
[0017] The finger parts include a thumb part (movable part 20) and four finger parts 11 corresponding to the index finger, middle finger, ring finger, and little finger. The joint device 1 forms a thumb joint having the hand body as the base part 10 and the thumb part as the movable part 20. An attachment base 12 for attaching the spherical bearing 30 is provided on the base part 10.
[0018] FIG. 3 is an exploded perspective view of the peripheral structure of the spherical bearing 30 according to an embodiment of the present disclosure. As shown in FIG. 3, the spherical bearing 30 has an inner ring 31 and an outer ring 32. The inner ring 31 is attached to the attachment base 12 via bolts 60, a first collar 61, and a second collar 62.
[0019] The first collar 61 and the second collar 62 are each formed in a cylindrical shape with a flange at one end, and are inserted from both sides into through holes formed in the inner ring 31. The bolt 60 is inserted through the inside of the inner ring 31, the first collar 61, and the second collar 62, and screwed into the mounting base 12. This fixes the inner ring 31 to the base portion 10.
[0020] An annular guide member 50 is attached to the outer circumference of the outer ring 32 by bolts or the like (not shown). The guide member 50 is provided with a first wire attachment portion 51, a second wire attachment portion 52, and a rotation restricting portion 53. The rotation restricting portion 53 protrudes downward from the lower side (mounting base 12 side) of the guide member 50. The rotation restricting portions 53 are provided in pairs, straddling the central axis of the guide member 50.
[0021] The rotation restricting portion 53 is provided with a contact portion 53a that contacts the base portion 10 (mounting base 12). The contact portion 53a has a curved shape centered on the pitch axis (Y axis) so as to allow the rotation of the outer ring 32 around the pitch axis (Y axis) as shown in Figure 1. The rotation restricting portion 53 has a first wire attachment portion 51 and a wire guide attachment portion 56 formed thereon, as shown in Figure 3. The first wire attachment portion 51 is formed to penetrate the rotation restricting portion 53 in the radial direction.
[0022] The wire guide mounting portion 56 is located above the first wire mounting portion 51. The wire guide mounting portion 56 is formed in a concave shape on the portion that protrudes radially outward from the outer circumferential surface of the guide member 50. As shown in Figure 2, an arc-shaped wire guide 54 is attached to the wire guide mounting portion 56. In addition, as shown in Figure 3, a connecting portion 55 for connecting the movable portion 20 is formed on the outer circumferential surface of the guide member 50.
[0023] The second wire attachment portion 52 is provided on the lower side (mounting base 12 side) of the guide member 50. The second wire attachment portion 52 is provided in a pair with the rotation restricting portion 53 (first wire attachment portion 51) on either side of the central axis of the guide member 50, at a 90° angle in plan view. The second wire attachment portion 52 is formed by a projection that extends downward from the lower surface of the guide member 50 and passes through it radially.
[0024] Figure 4 is a perspective view of the joint device 1 according to one embodiment of the present disclosure, as seen from the connection portion 55 side. Note that the movable portion 20 has been removed in Figure 4. As shown in Figure 4, a pair of arc-shaped openings 12a are formed on the upper side (guide member 50 side) of the mounting base 12. The pair of openings 12a are formed inward from the rotational trajectory of the rotation restricting part 53. As a result, the contact portion 53a of the rotation restricting part 53 is always in contact with the upper surface of the mounting base 12. A pair of wire guides 12b are provided on the lower side of the mounting base 12.
[0025] Figure 5 is a perspective view showing the connection state between the first wire attachment portion 51 and the wire pulling device 40 according to one embodiment of the present disclosure. As shown in Figure 5, the first wire attachment section 51 is connected to the first wire 41 extending from the wire traction device 40. The first wire 41 consists of two wires 41a and 41b, which are individually attached to a pair of first wire attachment sections 51.
[0026] The wire guide 54 has an arc-shaped guide groove formed therein to guide the first wire 41 in the circumferential direction. The base portion 10 has a first hole portion 13 formed therein to guide the first wire 41 into the interior. The first wire 41 guided into the interior of the base portion 10 extends from a second hole portion 14 formed on the wrist side of the base portion 10 to the wire pulling device 40 (see Figure 1).
[0027] As shown in Figure 1, the wire pulling device 40 selectively pulls the wires 41a and 41b, thereby operating the pair of first wire attachments 51 provided on both sides of the spherical bearing 30 in the direction in which the pitch axis (Y axis) extends (Y axis direction). As a result, the wire pulling device 40 can rotate the outer ring 32 around the yaw axis (Z axis) via the guide member 50.
[0028] Figure 6 is a perspective view showing the connection between the second wire attachment portion 52 and the wire pulling device 40 according to one embodiment of the present disclosure. As shown in Figure 6, the second wire 42 extending from the wire traction device 40 is connected to the second wire attachment section 52. The second wire 42 consists of two wires 42a and 42b, which are individually attached to a pair of second wire attachment sections 52.
[0029] A guide hole 12c is formed in the center of the lower surface of the mounting base 12, communicating with a pair of openings 12a (see Figure 4). The second wire 42, passing through the guide hole 12c, is guided to the base portion 10 side through a pair of wire guides 12b and extends to the wire pulling device 40 (see Figure 1).
[0030] As shown in Figure 1, the wire pulling device 40 selectively pulls the wires 42a and 42b, thereby operating the pair of second wire attachments 52 provided on both sides of the spherical bearing 30 in the direction in which the roll axis (X axis) extends (X axis direction). This allows the wire pulling device 40 to rotate the outer ring 32 around the pitch axis (Y axis) via the guide member 50.
[0031] Figure 7 shows the radial abduction and ulnar adduction of the movable part 20 according to one embodiment of the present disclosure. As shown in Figure 7, the movable part 20 can be abducted radially and inducted ulnarly by the spherical bearing 30. Specifically, as shown in Figure 1, when the wire pulling device 40 pulls the wire 41a, the movable part 20 rotates inductively ulnarly around the yaw axis (Z axis). Also, when the wire pulling device 40 pulls the wire 41b, the movable part 20 rotates radially abducted around the yaw axis (Z axis). At this time, the rotation restricting part 53 contacts the base part 10 side, thereby restricting the rotation of the movable part 20 around the roll axis (X axis).
[0032] Figure 8 shows the palmar abduction and palmar adduction of the movable part 20 according to one embodiment of the present disclosure. As shown in Figure 8, the movable part 20 can be abducted and adducted palmar-side by the spherical bearing 30. Specifically, as shown in Figure 1, when the wire pulling device 40 pulls the wire 42a, the movable part 20 adducts palmar-side around the pitch axis (Y axis). Also, when the wire pulling device 40 pulls the wire 42b, the movable part 20 abducts palmar-side around the pitch axis (Y axis). At this time, the rotation restricting part 53 contacts the base part 10 side, thereby restricting the rotation of the movable part 20 around the roll axis (X axis).
[0033] As described above, the joint device 1 comprises a base portion 10, a movable portion 20 that moves relative to the base portion 10, a spherical bearing 30 having an inner ring 31 fixed to the base portion 10 side and an outer ring 32 fixed to the movable portion 20 side, a wire traction device 40 that pulls wires (first wire 41, second wire 42) connected to the outer ring 32 side to rotate the outer ring 32 around two of the rotation axes (pitch axis (Y axis), yaw axis (Z axis)) out of the roll axis, pitch axis, and yaw axis, and a rotation restricting portion 53 that restricts the rotation of the outer ring 32 around the remaining rotation axis (roll axis (X axis)) that is not one of the two rotation axes. With this configuration, the wire traction drive type joint device 1 can reproduce rotational motion with two degrees of freedom in one joint.
[0034] Furthermore, in one embodiment of this disclosure, the rotation restricting portion 53 is provided on the outer ring 32 side and includes a contact portion 53a that contacts the base portion 10. With this configuration, the rotation restricting portion 53 contacts the base portion 10, thereby restricting the rotation of the outer ring 32 around the roll axis (X axis).
[0035] Furthermore, in one embodiment of this disclosure, the contact portion 53a is provided in pairs on both sides of the spherical bearing 30 in the direction in which one of the two rotation axes (pitch axis (Y axis) and yaw axis (Z axis)) extends. With this configuration, the rotation restricting portion 53 can restrict the rotation of the outer ring 32 on both sides in the rotational direction around the roll axis (X axis).
[0036] Furthermore, in one embodiment of this disclosure, the contact portion 53a has a curved shape centered on one of the rotation axes (pitch axis (Y axis)). With this configuration, the rotation restricting portion 53 can allow the rotation of the outer ring 32 around the pitch axis (Y axis).
[0037] Furthermore, in one embodiment of this disclosure, a guide member 50 is provided attached to the outer ring 32 and to which wires (first wire 41, second wire 42) are connected. This configuration makes it easier to connect the wires to the outer ring 32.
[0038] Furthermore, in one embodiment of the present disclosure, the guide member 50 has a pair of first wire attachment portions 51 provided in the direction in which one of the two rotation axes (pitch axis (Y axis)) extends, and the wire pulling device 40 includes a first wire 41 connected to the first wire attachment portion 51. With this configuration, the outer ring 32 can be rotated around the yaw axis (Z axis) by selectively pulling the first wire 41.
[0039] Furthermore, in one embodiment of this disclosure, the rotation restricting portion 53 is provided on the guide member 50, and the first wire attachment portion 51 is formed on the rotation restricting portion 53. With this configuration, since the first wire attachment portion 51 and the rotation restricting portion 53 are integrally provided on the guide member 50, the number of parts can be reduced and the device can be miniaturized.
[0040] Furthermore, in one embodiment of the present disclosure, the guide member 50 has a pair of second wire attachment portions 52 provided in the direction in which the remaining rotation axis (roll axis (X axis)) extends, and the wire pulling device 40 includes a first wire 41 connected to the second wire attachment portion 52. With this configuration, the outer ring 32 can be rotated around the pitch axis (Y axis) by selectively pulling the second wire 42.
[0041] Furthermore, one embodiment of the robot hand device of this disclosure comprises a hand body (base portion 10), finger parts (movable portion 20) that are movable relative to the hand body, and the joint device 1 that connects the hand body and the finger parts. With this configuration, a compact design can be achieved, and the movement of the finger parts can be made to closely resemble the movements of a human hand.
[0042] Furthermore, in one embodiment of this disclosure, the finger part is a thumb part, and the thumb part is capable of palmar abduction and palmar adduction, radial abduction and ulnar adduction by the joint device 1. With this configuration, the movement of the thumb part can be reproduced in a compact form.
[0043] Furthermore, the above-described embodiment of the present disclosure may be modified as follows.
[0044] For example, the joint device 1 combines a spherical bearing 30 with a wire traction drive system to enable a wide range of rotational movements. By keeping the wires, which are wired to each of the two degrees of freedom on the guide member 50, taut, it can be kept under constant tension from multiple directions. By pulling the first wire 41 fixed to the side of the guide member 50, radial abduction and ulnar adduction can be performed, and by pulling the second wire 42 fixed to the bottom of the guide member 50, palmar abduction and palmar adduction can be performed. During each rotational movement, the rotation restricting part 53 of the guide member 50 restricts the direction of movement, preventing it from being affected by the rotation of the other side and allowing rotation in the intended direction for each degree of freedom. It is also possible to rotate the thumb diagonally by simultaneously pulling both wires.
[0045] Joint device 1 can reproduce the high degree of freedom of the thumb joint (CM joint), which is considered extremely difficult to replicate in humanoid five-finger robotic hand devices. By making the robotic hand device's movements as close as possible to those of a human hand, it becomes possible to perform fine movements such as holding and pinching small objects, enabling the manufacture of highly accurate five-finger robotic hand devices.
[0046] Furthermore, joint device 1 can be applied to locations requiring two or more degrees of freedom in a single place. For example, joint device 1 is used in a robotic hand device that mimics the "base joint of the thumb," but since the shoulder, elbow, and wrist are also joints with high degrees of freedom in the human body, they can be similarly replaced. By applying joint device 1 to parts that are difficult to reproduce with high degrees of freedom, it is possible to create an entire human body, such as arms and legs, as another body (avatar).
[0047] Furthermore, the need for fine motor skills in human hands is not limited to robotic hand devices; it also applies to medical devices such as prosthetic arms and legs. Since prosthetic arms and legs are medical devices that replace human joint movements, applying them to joint areas can make them more closely resemble actual joint movements.
[0048] Furthermore, by applying this technology to the manipulator hands of industrial robots used in production lines, the range of media that can be handled can be expanded. Manipulator hands that perform assembly, picking, and placing on production lines often have two to three fingers, and the types of parts that can be grasped by the manipulator hand are often limited. In the case of irregularly shaped media or media with shapes that are difficult to grasp, methods such as changing the manipulator hand with a tool changer or determining the orientation of the media using a camera recognition function can be used, but these methods incur costs such as preparing replacement hands, increasing the number of tasks involved in switching hands during work, and preparing control software and equipment. By applying the joint device 1 to the manipulator hand, the fingers can move flexibly, making it possible to continuously grasp media by switching the gripping method according to the shape and orientation of the media, thereby suppressing the increase in tasks and costs.
[0049] Although embodiments of this disclosure have been described in detail above with reference to the drawings, the specific configurations are not limited to these embodiments and include design modifications and the like that do not depart from the gist of this disclosure. Furthermore, each embodiment can be combined with other embodiments as appropriate.
[0050] Furthermore, some or all of the above embodiments may also be described as follows, but are not limited to the following.
[0051] (Note 1) The base part, A movable part that moves relative to the base part, A spherical bearing having an inner ring fixed to the base portion and an outer ring fixed to the movable portion, A wire pulling device that pulls a wire connected to the outer ring and rotates the outer ring around two of the rotation axes, the roll axis, the pitch axis, and the yaw axis, The system includes a rotation restricting unit that restricts the rotation of the outer ring around the remaining rotation axis, which is not one of the two rotation axes mentioned above. Joint device.
[0052] (Note 2) The rotation restricting portion is provided on the outer ring side and includes a contact portion that contacts the base portion. The joint device described in Appendix 1.
[0053] (Note 3) The aforementioned contact portions are provided in pairs on both sides of the spherical bearing in the direction in which one of the two rotating shafts extends. The joint device described in Appendix 2.
[0054] (Note 4) The contact portion has a curved shape centered on one of the rotation axes. Joint device as described in Appendix 2 or 3.
[0055] (Note 5) The outer ring is attached to a guide member to which the wire is connected, A joint device as described in any one of the appendices 1 to 4.
[0056] (Note 6) The guide member has a pair of first wire attachment portions provided in the direction in which one of the two rotation axes extends, The wire traction device comprises a first wire connected to the first wire attachment portion. The joint device described in Appendix 5.
[0057] (Note 7) The rotation restricting portion is provided on the guide member, The first wire attachment portion is formed in the rotation restricting portion. The joint device described in Appendix 6.
[0058] (Note 8) The guide member has a pair of second wire attachment portions provided in the direction in which the remaining rotation axis extends, The wire traction device comprises a second wire connected to the second wire attachment portion. A joint device as described in any one of the appendices 5 to 7.
[0059] (Note 9) The hand unit and A movable finger part relative to the hand body, The hand comprises a joint device described in any one of appendices 1 to 8, which connects the hand body and the finger parts. Robot hand device.
[0060] (Note 10) The aforementioned finger part is a thumb part, The thumb part is capable of palmar abduction and palmar adduction, radial abduction and ulnar adduction by the joint device. The robot hand device described in Appendix 9. [Explanation of symbols]
[0061] 1. Joint device 10 Base section 11 finger parts 12 Mounting base 12a opening 12b Wire guide 12c Guide hole 13 First hole 14 2nd hole 20 Moving parts 30 Spherical bearings 31 Inner circle 32 Outer ring 40 Wire pulling device 41. First wire 41a Wire 41b Wire 42. Second wire 42a Wire 42b Wire 50 Guide members 51 First wire attachment section 52 Second wire attachment section 53 Rotation restriction section 53a Contact part 54 Wire Guide 55 Connection part 56 Wire guide mounting section 60 volts 61 First Color 62. Second color
Claims
1. The base part, A movable part that moves relative to the base part, A spherical bearing having a spherical inner ring fixed to the base portion and an annular outer ring fixed to the movable portion, A wire pulling device that pulls a wire connected to the outer ring side, and rotates the outer ring around two rotation axes, the pitch axis and the yaw axis, which are located in the axial direction of the outer ring's central axis and perpendicular to the roll axis and the pitch axis, respectively. It includes a rotation restricting unit that restricts the rotation of the outer ring around the roll axis, The base portion comprises a mounting base to which the inner ring is attached, The wire traction device is A pair of first wires rotate the outer ring around the yaw axis, The system comprises a pair of second wires that rotate the outer ring around the pitch axis, The rotation restricting portion is provided on the outer ring side and includes a contact portion that contacts the upper surface of the mounting base when the outer ring rotates around the roll axis. Joint device.
2. The aforementioned contact portions are provided in pairs on both sides of the outer ring in the direction in which the pitch axis extends. The joint device according to claim 1.
3. The contact portion has a curved shape centered on the pitch axis. The joint device according to claim 2.
4. The outer ring is attached to a guide member to which the wire is connected, The joint device according to any one of claims 1 to 3.
5. The guide members are provided in pairs in the direction in which the pitch axis extends, and each has a first wire attachment portion to which the pair of first wires are connected. The joint device according to claim 4.
6. The first wire attachment portion is provided integrally with the rotation restricting portion. The joint device according to claim 5.
7. The guide members are provided in pairs in the direction in which the roll shaft extends, and each has a second wire attachment portion to which the pair of second wires are connected. The joint device according to claim 4.
8. The hand unit and A movable finger part relative to the hand body, The device comprises a joint device according to any one of claims 1 to 3, which connects the hand body and the finger parts. Robot hand device.
9. The aforementioned finger part is a thumb part, The thumb part is capable of palmar abduction and palmar adduction, radial abduction and ulnar adduction by the joint device. The robot hand device according to claim 8.