Finger joint drive mechanism for humanoid robot hand
By introducing driving combination members of arc gears and speed reduction devices into the joints of humanoid robot hands, precise control and multi-directional movement of joints are achieved, and the problems of small freedom and inaccurate control of joint driving mechanisms in the prior art are solved, and the adaptability and accuracy of robot hands are improved.
Patent Information
- Application Number
- JP2023210605
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2022-12-13
- Filing Date
- 2023-12-13
- Publication Date
- 2025-04-21
- Estimated Expiration
- 2043-12-13
AI Technical Summary
The joint drive mechanism of existing humanoid robot hands has small degrees of freedom and the inability to precisely control the curvature motion of each joint, limiting its adaptability and accuracy on complex tasks.
A new joint drive mechanism is adopted to achieve precise control of the joint and multi-directional movement by introducing arc gears and speed reduction devices into the joints. The mechanism includes a joint with arc gear and a driving combination member with a reduction device. By precisely controlling the rotation of the driving combination member, the up and down swing of the joint is achieved.
This mechanism improves the freedom and adaptability of the joints, achieves precise control of each joint, and enables more flexibility in completing complex grasping and operation tasks.
Smart Images

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Abstract
Description
[Technical field]
[0001] The present invention relates to a robot hand configuration, and more particularly to a finger joint drive mechanism for a humanoid robot hand. [Background technology]
[0002] With the rise and development of the robotics industry, anthropomorphic robot hands that mimic the structure of the human hand are now able to perform certain tasks like human hands. Research on multi-fingered robot hands focuses on the functionality that allows them to perform dexterous manipulation. Summary of the Invention [Problem to be solved by the invention]
[0003] Conventional humanoid robot hands are designed to grasp objects, so that the finger joints are pivotally connected to each other and move with a predetermined degree of freedom when driven. In conventional patent documents, for example, in the prosthetic hand device described in the following Patent Document 1, each finger joint is pivotally connected to each other by a link rod, and the link rod of the finger joint at the head end is connected by a linear drive element. When the linear drive element is operated, each finger joint is driven so that the link rods pull each other to perform a bending or straightening movement. However, although a robot hand configured with this structure achieves the effect of grasping an object like a human hand, the finger joints driven by the link rods not only have a small degree of freedom, but also cannot individually control the bending movement of each finger joint to accurately position it, so it can only perform simple grasping tasks.
[0004] In addition, other conventional designs in which each finger joint is pulled by a cable and pivoted to each other achieve bending and straightening movements, and mainly generate corresponding pivoting movements by pulling the finger joints in a manner that imitates the tendons of a human hand. However, such robot hands require a large drive device for winding up the cables, and the cables that drive each finger are installed so as to be wound around the robot hand, making the overall structure of such robot hands more complicated and insufficient in that the bending movements of each finger joint cannot be individually controlled and accurately positioned. [Prior art documents] [Patent documents]
[0005] [Patent Document 1] China Patent Application Publication No. 108189065
[0006] Therefore, the present inventors believed that the above-mentioned drawbacks could be improved, and as a result of extensive research, they came to propose the present invention, which effectively improves the above-mentioned problems through rational design.
[0007] The present invention has been made in view of the above circumstances, and its object is to provide a finger joint drive mechanism for a humanoid robot hand which simplifies the structural configuration, effectively utilizes space to reduce volume, ensures a reduction ratio, and at the same time achieves the effects of increasing adaptability and precise control. [Means for solving the problem]
[0008] The main invention to achieve the above object is: A first finger joint having a first pivot portion and a first joint portion at one end, and a rack arranged in an arc shape along the Y-axis direction at the first joint portion; A second finger joint extending along an X-axis direction and having a hollow shape with an accommodation space formed therein, the second finger joint having a tip and a distal end opposite to the tip along the X-axis direction, the second finger joint pivotally connected to a first pivotal part of the first finger joint by the tip, and a second pivotal part and a second joint part formed at the distal end; a reduction gear unit having a drive shaft protruding toward the first joint portion, a central axis of the drive shaft being perpendicular to the Y-axis direction, a drive gear being connected to the drive shaft and meshing with the rack, the reduction gear unit being used to reduce the rotation speed of the motor unit and to output power through the drive shaft, when the motor unit drives the drive shaft to rotate through the reduction gear unit, the drive gear is driven in synchronous with the drive shaft to move along the rack, and the second finger joint is driven to pivot upward or downward at a predetermined angle relative to the first finger joint.
[0009] Other objects, configurations and effects of the present invention will become apparent from the following detailed description of the preferred embodiments of the present invention. [Brief description of the drawings]
[0010] [Figure 1] FIG. 2 is an exploded view showing a schematic diagram of a finger joint drive mechanism of the humanoid robot hand according to one embodiment of the present invention. [Diagram 2] FIG. 2 is an external perspective view showing a finger joint driving mechanism of the humanoid robot hand according to one embodiment of the present invention. [Diagram 3] FIG. 1 is a schematic configuration diagram showing a combination of finger joint drive mechanisms of a humanoid robot hand according to an embodiment of the present invention. [Figure 4] 4 shows an example of a partially enlarged view of FIG. 3. [Diagram 5]13A and 13B are schematic diagrams illustrating an example of a case where each finger joint of a finger joint drive mechanism of a humanoid robot hand according to an embodiment of the present invention pivots downward. [Figure 6] 13A and 13B are schematic diagrams illustrating an example of a case where each finger joint of a finger joint drive mechanism of a humanoid robot hand according to an embodiment of the present invention pivots downward. [Figure 7] 13A and 13B are schematic diagrams illustrating an example of a case where a first finger joint of a finger joint drive mechanism of a humanoid robot hand according to an embodiment of the present invention swings laterally and inclined relative to a drive combination member; [Figure 8] 13A and 13B are schematic diagrams illustrating an example of a case in which a first finger joint of a finger joint drive mechanism of a humanoid robot hand according to an embodiment of the present invention swings at a lateral inclination relative to a drive combination member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] Hereinafter, the embodiments of the present invention will be described in detail. However, the present invention is not limited to these, and various modifications are possible within the scope of the description. The technical scope of the present invention also includes embodiments obtained by appropriately combining the technical means disclosed in the different embodiments.
[0012] First, the finger joint drive mechanism of the humanoid robot hand according to the present invention will be described with reference to Figs. 1 to 4. The finger joint drive mechanism of the humanoid robot hand according to the present invention is mainly composed of a first finger joint 11, a second finger joint 21, a third finger joint 31, and a fourth finger joint 41 which are pivotally connected in sequence. A drive combination member 51 is installed inside each of the first finger joint 11, the second finger joint 21, the third finger joint 31, and the fourth finger joint 41. Each of these will be described below.
[0013] <First finger joint 11> One end has a first pivot portion 12 that is convexly provided on both the left and right sides along the Z-axis direction, and a first joint portion 13 that is sheet-shaped and convexly provided toward the front along the X-axis direction, and the first joint portion 13 is provided with a rack 14 that is arranged in an arc shape along the Y-axis direction.
[0014] <Second finger joint 21> The second finger joint 21 is hollow and extends along the X-axis direction, and has an accommodation space 22 extending along the X-axis direction. In this embodiment, the second finger joint 21 is formed by assembling a first half housing 211 and a second half housing 212 together, and in other possible embodiments, the second finger joint 21 is integrally formed by a hollow cylinder having at least one open end or a truss-type support frame. The present invention does not limit the configuration structure or manufacturing method of the finger joint itself. The second finger joint 21 has a tip 23 and an end 24 on the opposite side of the tip 23 at both ends along the X-axis direction, and the second finger joint 21 is pivotally attached to the first pivot part 12 of the first finger joint 11 by a through hole 231 of the tip 23, and the first joint part 13 is received in the tip 23. At the end 24, a second pivot portion 26 is formed which is convexly provided on both opposing sides along the Z-axis direction, and a second joint portion 27 is formed in a sheet-like shape which convexly faces forward along the X-axis direction, and the second joint portion 27 is provided with another rack 28 which is arranged in an arc shape along the Y-axis direction.
[0015] <Drive combination member 51> The drive combination 51 is installed to correspond to the receiving space 22, and is a motor of a reducer or is composed of a combination of a motor and a reducer. The drive combination 51 includes a reducer unit 52 and a motor unit 53 that are connected to each other along the X-axis direction and are arranged so that the same central axis L is connected in series. The motor unit 53 is composed of a servo motor, the reducer unit 52 has a drive shaft 521 that is projected toward the first joint and located on its central axis L, the central axis L of the drive shaft 521 is perpendicular to the Y-axis direction, and the drive shaft 521 is connected to a drive gear 54 that is meshed with the rack 14. The drive gear 54 is composed of a bevel gear or a hypoid gear, and a pre-installed reduction gear set (not shown) is arranged inside the reducer unit 52, and the reducer unit 52 is used to output power through the drive shaft 521 after reducing the rotation speed of the motor unit 53. The reducer unit 52 may be a commonly used reducer, as long as it can reduce the rotation speed of the motor unit 53 and output a predetermined torque. The reducer unit 52 and the motor unit 53 are arranged to be connected in series in the receiving space 22 with the same central axis L, so that the configuration of the driving combination member 51 can further utilize the space and reduce the overall volume, and also reduce the wear caused by the complexity of the member configuration, and provide a sufficiently large reduction ratio during the driving process. When the motor unit 53 drives its drive shaft 521 to rotate by the reducer unit 52, the driving gear 54 is driven to move along the rack 14, and the second finger joint 21 is smoothly driven to pivot up or down at a predetermined angle with respect to the first finger joint 11 along the Y-axis direction, so that the second finger joint 21 swings between a straight position A and a curved position B with respect to the first finger joint 11. When the second finger joint 21 is in the straight position A, the central axis L of the drive shaft 521 is perpendicular to the Y-axis direction, and an angle sensor is further installed in the motor unit 53 to precisely control the movement position of the finger joint and accurately imitate the bending and straightening movement of a human finger joint.
[0016] <Third finger joint 31> The third finger joint 31 is pivotally connected to the second pivot part 26 by its tip 33, and the fourth finger joint 41 is pivotally connected to the end 34 of the third finger joint by its tip 43, and the third finger joint 31 and the fourth finger joint 41 are each provided with the same drive combination member 51 as the second finger joint 21. The third finger joint 31 is provided with the rack 28 having the same arc shape as the second finger joint 21 at its end 34, so that the third finger joint 31 and the fourth finger joint 41 move along the corresponding rack 28 by the drive gear 54 to which they belong, and the third finger joint 31 and the fourth finger joint 41 are individually driven to pivot upward or downward at a predetermined angle along the Y-axis direction. Referring to Figures 5 and 6, when the drive combination members 51 of the second finger joint 21, the third finger joint 31, and the fourth finger joint 41 are driven to rotate forward or backward, the corresponding finger joint is driven to perform a bending or straightening operation. In addition, the finger joint positions of the present invention are independently driven, which provides greater adaptability and achieves precise control.
[0017] A receiving seat 15 is formed to protrude from the other end of the first finger joint 11, and a drive rack 16 is provided on the receiving seat 15 so as to form an arc along the Z-axis direction. The drive combination member 71 includes a drive motor 72 and a second reducer unit 73 connected to the drive motor 72, and the second reducer unit 73 has an output shaft 74 protruding along the X-axis direction. The output shaft 74 and the drive shaft 521 share the same central axis L, and an output gear 75 made of a bevel gear or a hypoid gear is connected to the outer periphery of the output shaft 74. The output gear 75 is intermeshed with the drive rack 16. When the drive motor 72 drives the output shaft 74 through the reducer unit 73, as shown in FIG. 7 and FIG. 8, the output gear 75 pushes the drive rack 16 to move, and smoothly drives the first finger joint 11 to swing inclined to the left or right at a predetermined angle along the Z-axis direction relative to the drive combination 71, and drives each of the remaining finger joints to swing deflected laterally, thereby improving the adaptability of their movements.
[0018] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention. [Explanation of symbols]
[0019] 11 First knuckle 12 1st pivot joint 13 First joint 14 Rack 15 Receiving seat 16 Dry Black 21 Second knuckle 211 1st Half Housing 212 Second Half Housing 22 Containment Space 23 Tip 231 Through hole 24 Terminal 25 Assembly groove 26 2nd pivot joint 27 Second joint 28 LACK 31 Third knuckle 33 Tip 34 Terminal 41 Fourth knuckle 43 Tip 51 Drive assembly member 52 Reducer unit 521 Drive shaft 53 Motor unit 54 Drive gear 71 Drive assembly member 72 Drive motor 73 Second reduction gear unit 74 Output shaft 75 Output Gear L center axis
Claims
1. A first finger joint having a first pivot portion and a first joint portion at one end, and a rack disposed in an arc shape along the Y-axis direction at the first joint portion; a second finger joint extending along an X-axis direction, being hollow, and having an accommodation space formed therein, the second finger joint having a tip along the X-axis direction and an end opposite to the tip, the second finger joint being pivotally attached to a first pivot part of the first finger joint at the tip, and a second joint part protruding in a sheet shape at the end, and a second pivot part protruding in a sheet shape at one side of the second joint part so as to protrude toward both opposing sides along the Z-axis direction; a drive combination member installed in the accommodation space, the drive combination member including a reducer unit and a motor unit connected to each other along the X-axis direction, the reducer unit having a drive shaft protruding toward the first joint portion, a central axis of the drive shaft being perpendicular to the Y-axis direction, the drive shaft being connected to a drive gear meshed with the rack, the reducer unit being used to reduce a rotation speed of the motor unit and output power through the drive shaft, when the motor unit drives the drive shaft to rotate through the reducer unit, the drive gear is driven synchronously to move along the rack, and a second finger joint is driven to pivot upward or downward at a predetermined angle relative to the first finger joint, the second joint portion is provided with another rack arranged to form an arc along the Y-axis direction, the other rack being provided on a side surface of the second joint portion opposite to one side surface of the second joint portion on which the second pivot portion is provided, a third finger joint is pivotally connected to the second pivot portion by its tip, and a drive combination member the same as that of the second finger joint is provided on the third finger joint, the drive combination member moves along the other rack when a drive gear of the third finger joint rotates, and the third finger joint is further driven to pivot upward or downward at a predetermined angle relative to the second finger joint.
2. 2. The finger joint drive mechanism of a humanoid robot hand according to claim 1, wherein the first pivot portion is provided in a convex shape toward both opposing sides of the second finger joint along the Z-axis direction, the first joint portion is provided in a sheet-like shape toward the front along the X-axis direction, and the second finger joint is pivotally connected to the first pivot portion of the first finger joint by a through hole at its tip, and the first joint portion is housed in the tip.
3. 2. The finger joint drive mechanism for a humanoid robot hand according to claim 1, wherein the reducer unit and the motor unit are arranged to be connected in series in the accommodation space by a common central axis.
4. 2. The finger joint drive mechanism of claim 1, wherein the other end of the first finger joint has a receiving seat, and the receiving seat is provided with a drive rack arranged in an arc shape along the Z-axis direction. The drive combination member includes a drive motor and a second reducer unit connected to the drive motor. The second reducer unit has an output shaft, and an output gear is circumferentially provided on the outer periphery of the output shaft. The output gear is meshed with the drive rack. When the drive motor drives the second reducer unit to operate the output shaft, the drive rack is pushed by the output gear, and the first finger joint is driven to swing at an angle to the left or right relative to the drive combination member.
Citation Information
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