Dexterous hand fingers, dexterous hand and robot
By designing the finger structure of a dexterous hand, torque distribution and auxiliary drive torque redistribution of multiple joints were achieved, solving the problem of excessive load on the proximal joints and insufficient drive capability at the distal joints, thus improving grip stability and system efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ASTRIBOT CO LTD
- Filing Date
- 2026-06-17
- Publication Date
- 2026-07-17
AI Technical Summary
Dexterous hands suffer from excessive load on the proximal joints and insufficient distal actuation capacity, which affects the stability of the fingers in grasping objects.
Design a finger structure for a dexterous hand, including a drive shaft, a pulley, and tendon cords. Through a reversing structure and a continuous drive path of tendon cords, torque distribution and redistribution of auxiliary drive torques are achieved across multiple joints, reducing the drive load on proximal joints.
It improves the finger's ability to envelop the target object and the stability of gripping, reduces the drive source load of the proximal joint, and improves the system's output capability and efficiency.
Smart Images
Figure CN122401482A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of dexterous hand technology, and more specifically, to a finger of a dexterous hand, a dexterous hand, and a robot. Background Technology
[0002] The fingers of a human hand have three joints and three degrees of freedom. A dexterous hand is the end effector of a robot. The fingers of a dexterous hand are an important component of it. The three degrees of freedom of the fingers in a dexterous hand enable it to more closely resemble the functions of a human hand.
[0003] However, in related technologies, dexterous hand fingers suffer from excessive proximal joint load and insufficient distal actuation capability, which in turn affects the stability of the fingers' grasping of objects. Summary of the Invention
[0004] This application addresses the shortcomings of existing methods by proposing a dexterous hand finger, a dexterous hand, and a robot to solve the technical problem that the proximal joints of the dexterous hand fingers are subjected to excessive load while the distal actuation capability is insufficient, thus affecting the stability of the fingers' grasping of objects.
[0005] In a first aspect, embodiments of this application provide a finger of a dexterous hand, comprising: The device includes a metacarpophalangeal joint, a proximal interphalangeal joint, and a distal interphalangeal joint. The metacarpophalangeal joint includes a drive shaft, the proximal interphalangeal joint includes a first rope pulley, and the distal interphalangeal joint includes a second rope pulley. The axes of the drive shaft, the first rope pulley, and the second rope pulley are all parallel to a first shaft. The radius of the drive shaft is smaller than the radius of the first rope pulley and the radius of the second rope pulley. The drive source is configured to at least drive the drive shaft to rotate about the first axis; The reversing structure includes at least a first reversing bearing, a second reversing bearing located between the drive shaft and the first sheave, and a third reversing bearing located between the first sheave and the second sheave; The tendon cord sequentially passes around the first reversing bearing, the peripheral side of the drive shaft away from the first rope wheel, the second reversing bearing, the peripheral side of the first rope wheel near the second rope wheel, the third reversing bearing, and the peripheral side of the second rope wheel near the first rope wheel, and is fixedly connected to the second rope wheel; the tendon cord is configured to apply an auxiliary driving torque about the first axis to the drive shaft when it drives the distal finger joint to rotate about the first axis.
[0006] Optionally, the fingers of the dexterous hand in this embodiment of the application further include a drive wheel, and the tendon rope is wound around the drive wheel at one end away from the second rope wheel, and the drive wheel is configured to be connected to a third drive source.
[0007] Optionally, one end of the tendon cord away from the second pulley extends to the outside of the fingers of the dexterous hand.
[0008] Optionally, the first reversing bearing is located between the drive wheel and the transmission shaft; both the first reversing bearing and the second reversing bearing are located within the metacarpophalangeal joint and on both sides of the transmission shaft along the second axis direction; The first reversing bearing and the second reversing bearing are configured such that the tendons on both sides of the drive shaft extend along a third axis, which is parallel to the length direction of the fingers of the dexterous hand.
[0009] Optionally, the metacarpophalangeal joint includes a lateral swing bracket rotatably disposed about a second axis, the lateral swing bracket being connected to the drive shaft; the second axis is perpendicular to the first axis; The side swing bracket has an installation space extending along the second axis, and the first reversing bearing is located within the installation space.
[0010] Optionally, the side swing bracket includes a second output wheel and a first reversing wheel fixed coaxially along a second axis, and the two ends of the drive shaft are connected to the first output wheel and the second reversing wheel; the circumferential side of the first output wheel meshes with the circumferential side of the first reversing wheel, and the circumferential side of the second output wheel meshes with the circumferential side of the second reversing wheel; The metacarpophalangeal joint also includes a first rope group, a second rope group, a first input wheel with its axis parallel to a second shaft, and a second input wheel with its axis parallel to a third shaft. The first input wheel and the second output wheel are located on the upper and lower sides of the transmission shaft, respectively. The first rope group is wound sequentially on the first input wheel, the first reversing wheel, and the first output wheel in a crisscross pattern. The second rope group is wound sequentially on the second input wheel, the second reversing wheel, and the second output wheel in a crisscross pattern. The second input wheel is connected to the drive shaft via the second joint bracket, and the second reversing bearing is rotatably connected to the second joint bracket.
[0011] The drive source includes a first drive source and a second drive source, the first input wheel is connected to the first drive source, and the second input wheel is connected to the second drive source; When the torsional torque on the first output wheel around the first axis is in the same direction as the torsional torque on the second reversing wheel around the first axis, the metacarpophalangeal joint rotates around the first axis; when the torsional torques on the second output wheel and the first reversing wheel around the second axis are in the same direction, the metacarpophalangeal joint rotates around the second axis.
[0012] Optionally, the proximal interphalangeal joint further includes a fixing bracket coaxially fixed with the first rope pulley, and the distal interphalangeal joint further includes a fixing wheel coaxially fixed with the second rope pulley; The fingers of the dexterous hand also include a third rope group, which includes a fifth rope and a sixth rope; the fifth rope and the sixth rope are intertwined in a cross shape between the fixed bracket and the fixed wheel, and are configured to achieve kinematic coupling between the proximal finger joint and the distal finger joint.
[0013] Optionally, the fifth rope is wound in an S-shape between the fixed bracket and the fixed wheel located on the first side of the first rope wheel, and the sixth rope is wound in an S-shape between the fixed bracket and the fixed wheel located on the second side of the first rope wheel.
[0014] Optionally, the fingers of the dexterous hand in this embodiment of the application further include a reset structure, which is disposed between the proximal interphalangeal joint and the metacarpophalangeal joint and is configured to extend and retract along the length direction of the fingers of the dexterous hand.
[0015] Secondly, embodiments of this application provide a dexterous hand, including the fingers of the dexterous hand described in the above embodiments.
[0016] Thirdly, embodiments of this application provide a robot including the fingers of the dexterous hand described in the above embodiments.
[0017] The beneficial technical effects of the technical solutions provided in this application include: In this embodiment, the tendon cord sequentially passes around the first reversing bearing, the circumferential surface of the drive shaft away from the first sheave, the second reversing bearing, the circumferential surface of the first sheave near the second sheave, the third reversing bearing, and the circumferential surface of the second sheave near the first sheave, and is fixedly connected to the second sheave. This allows for the formation of a continuous tendon cord drive path across the metacarpophalangeal joints, proximal interphalangeal joints, and distal interphalangeal joints within the fingers of a dexterous hand. Because the effective radius of action of the tendon cord at the proximal and distal interphalangeal joints is greater than that at the metacarpophalangeal joints, under the same tension conditions, the distal and proximal interphalangeal joints can obtain a larger output torque. The metacarpophalangeal joints obtain a smaller output torque. In other words, this embodiment can actively achieve torque distribution across multiple joints through the design of the effective radius at different joints.
[0018] Furthermore, when the distal interphalangeal joint contacts the target object, as the driving tendon tightens, the tendon tension continuously increases, and the driving torque obtained by the distal interphalangeal joint also increases accordingly, thus enabling the formation of a larger wrap angle in both the proximal and distal interphalangeal joint regions. Since the joints are connected by rigid phalanges, the reaction force generated by the distal interphalangeal joint is transmitted proximally along the rigid structure of the finger, thereby creating an additional auxiliary driving torque around the first axis at the metacarpophalangeal joint, achieving a redistribution of driving torque among multiple joints. This auxiliary driving torque causes the metacarpophalangeal joint to also bend around the first axis during the bending of both the distal and proximal interphalangeal joints, thus significantly improving the dexterous hand's ability to envelop the target object and its grip stability.
[0019] Furthermore, in this embodiment, the total torque ultimately borne by the metacarpophalangeal joint includes not only the main driving torque provided by its own drive source, but also the auxiliary driving torque transmitted back from the distal finger joint. In other words, compared to the fingers of a traditional dexterous hand, the drive source in this embodiment provides less main driving torque to enable the metacarpophalangeal joint to rotate around the first axis by the same angle. Thus, the continuous tendon-wire drive path constructed in this embodiment can also reduce the drive load of the drive source of the metacarpophalangeal joint, thereby solving the problem of excessive load on the proximal joints (including the metacarpophalangeal joints) and insufficient drive capability of the distal finger joints in traditional dexterous hands.
[0020] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description
[0021] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 A schematic diagram of the structure of the fingertips of a dexterous hand provided in an embodiment of this application; Figure 2 For along Figure 1 Schematic diagram of the cross-sectional structure along the AA direction; Figure 3 for Figure 2 A magnified view of the structure at point B in the middle; Figure 4 This is a schematic diagram of the metacarpophalangeal joint provided in an embodiment of this application; Figure 5 A schematic diagram of the structure of the first rope assembly, the first input wheel, the first reversing wheel, and the first output wheel provided in an embodiment of this application; Figure 6 This is a schematic diagram of the structure of the second rope assembly, the second reversing wheel, and the second output wheel provided in an embodiment of this application. Figure 7A schematic diagram of the structure by which the third rope group achieves motion coupling at the proximal and distal finger joints is provided for embodiments of this application. Figure 8 A partial structural diagram of the fingers of a dexterous hand provided in an embodiment of this application. Explanation of reference numerals in the attached figures: 10-Metacarpophalangeal joints; 11-Drive shaft; 12-Side swing bracket; 121-Installation space; 122-First reversing wheel; 123-Second output wheel; 124-Bracket body; 13-First output wheel; 14-Second reversing wheel; 15-First input wheel; 16-Second input wheel; 17 - First rope group; 171 - First rope; 172 - Second rope; 18 - Second rope group; 181 - Third rope; 182 - Fourth rope; 19-Second joint support; 191-Extension; 20 - Proximal interphalangeal joints; 21-First pulley; 22-Fixed bracket; 23-First shaft; 30 - distal interphalangeal joint; 31-Second pulley; 32-Fixed pulley; 33-Second shaft; 40 - chordae tendon; 50 - drive wheel; 60 - Reversing structure; 61 - First reversing bearing; 62 - Second reversing bearing; 63 - Third reversing bearing; 70 - Third Rope Set; 71 - Fifth rope; 72 - Sixth rope; 80-Reset structure; X - First axis; Y - Second axis; Z - Third axis. Detailed Implementation
[0022] The embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the embodiments described below with reference to the accompanying drawings are exemplary descriptions for explaining the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions of the embodiments of this application.
[0023] Those skilled in the art will understand that, unless specifically stated otherwise, the terms "described" and "the" as used herein may also include plural forms. It should be further understood that the term "comprising" as used in the specification of this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude other features, information, data, steps, operations, elements, components, and / or combinations thereof supported by the art. The term "and / or" as used herein refers to at least one of the items defined by the term; for example, "A and / or B" can be implemented as "A," or as "B," or as "A and B."
[0024] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.
[0025] Among related technologies, structures that drive the distal finger joints to produce palmar flexion include traditional rope-driven structures that use multiple tendon ropes to drive different joints respectively. Although such structures have a certain degree of flexibility, they are insufficient in terms of multi-joint coordinated movement and load sharing due to the lack of a systematic driving force distribution mechanism.
[0026] Related technologies also include underactuated structures that use a single tendon rope to drive multiple joints and combine them with elastic elements to achieve adaptive gripping. Although this solution has good environmental adaptability, it is difficult to precisely adjust the motion and torque distribution of each joint due to the lack of independent control capability.
[0027] It is evident that the dexterous hand fingers in related technologies suffer from excessive proximal joint load and insufficient distal actuation capability, which in turn affects the stability of the fingers' grasping of objects.
[0028] Reference Figures 1-8 This application proposes a dexterous hand finger, a dexterous hand, and a robot to solve the technical problem in related technologies where the proximal joint of the dexterous hand finger has excessive load and insufficient distal actuation capability, which affects the stability of the finger's grasping of objects.
[0029] Reference Figures 1-3 The fingers of the dexterous hand in this embodiment include metacarpophalangeal joints 10, proximal interphalangeal joints 20, distal interphalangeal joints 30, a drive source, a reversing structure 60, and tendons 40.
[0030] The metacarpophalangeal joint 10 includes a drive shaft 11, the proximal interphalangeal joint 20 includes a first pulley 21, and the distal interphalangeal joint 30 includes a second pulley 31. The axes of the drive shaft 11, the first pulley 21, and the second pulley 31 are all parallel to a first axis X. The radius of the drive shaft 11 is smaller than the radii of the first pulley 21 and the second pulley 31. The drive source is configured to at least drive the drive shaft 11 to rotate about the first axis X.
[0031] The reversing structure 60 includes at least a first reversing bearing 61, a second reversing bearing 62 located between the drive shaft 11 and the first pulley 21, and a third reversing bearing 63 located between the first pulley 21 and the second pulley 31.
[0032] The tendon cord 40 sequentially passes over the first reversing bearing 61, the circumferential side of the drive shaft 11 away from the first pulley 21, the second reversing bearing 62, the circumferential side of the first pulley 21 near the second pulley 31, the third reversing bearing 63, and the circumferential side of the second pulley 31 near the first pulley 21, and is fixedly connected to the second pulley 31. The tendon cord 40 is configured to apply an auxiliary driving torque about the first axis X to the drive shaft 11 when it drives the distal finger joint 30 to rotate about the first axis X.
[0033] In this embodiment, the tendon cord 40 sequentially passes around the first reversing bearing 61, the peripheral side of the drive shaft 11 away from the first rope wheel 21, the second reversing bearing 62, the peripheral side of the first rope wheel 21 near the second rope wheel 31, the third reversing bearing 63, and the peripheral side of the second rope wheel 31 near the first rope wheel 21, and is fixedly connected to the second rope wheel 31, thereby forming a continuous driving path of the tendon cord 40 across the metacarpophalangeal joint 10, the proximal interphalangeal joint 20 and the distal interphalangeal joint 30 within the fingers of a dexterous hand.
[0034] Because the radius of the drive shaft 11 is smaller than the radius of the first pulley 21 and the second pulley 31, the tension of the tendon rope 40, which is driven continuously, remains constant. Let the tension of the tendon rope 40 be... The driving radius at the metacarpophalangeal joint 10 (MCP joint) is The driving radius at the proximal interphalangeal joint 20 (PIP joint) is The driving radius at the distal interphalangeal joint 30 (DIP joint) is The driving torques obtained by the metacarpophalangeal joint 10, proximal interphalangeal joint 20, and distal interphalangeal joint 30 respectively satisfy: (Expression 1) (Expression 2) (Expression 3) Wherein, T_M represents the driving torque obtained by the metacarpophalangeal joint 10; T_P represents the driving torque obtained by the proximal interphalangeal joint 20; and T_D represents the driving torque obtained by the distal interphalangeal joint 30.
[0035] Because the effective radius of action of the tendon 40 at the proximal interphalangeal joint 20 and the distal interphalangeal joint 30 is greater than that at the metacarpophalangeal joint 10, under the same tension conditions, the distal interphalangeal joint 30 and the proximal interphalangeal joint 20, with their larger effective radius of action, can obtain a greater output torque. The metacarpophalangeal joint 10, with its smaller effective radius of action, obtains a smaller output torque. In other words, the embodiments of this application can actively achieve torque distribution among multiple joints through the design of the effective radius at different joints, thereby enabling multiple joints to move collaboratively according to a preset ratio, rather than being controlled independently.
[0036] Furthermore, when the distal interphalangeal joint 30 contacts the target object, as the driving tendon 40 tightens, the tension of the tendon 40 continuously increases, and the driving torque obtained by the distal interphalangeal joint 30 also increases accordingly, thereby forming a larger wrap angle in the proximal interphalangeal joint 20 region and the distal interphalangeal joint 30 region. Since the joints are connected by rigid phalanges, the reaction force generated by the distal interphalangeal joint 30 will be transmitted proximally along the rigid structure of the finger, thereby forming an additional auxiliary driving torque around the first axis X at the metacarpophalangeal joint 10, realizing the redistribution of driving torque among multiple joints. This auxiliary driving torque causes the metacarpophalangeal joint 10 to bend around the first axis X during the bending of the distal interphalangeal joint 30 and the proximal interphalangeal joint 20, thereby significantly improving the dexterous hand's ability to wrap around the target object and the gripping stability.
[0037] Moreover, in this embodiment, the total torque ultimately borne by the metacarpophalangeal joint 10 includes not only the main driving torque provided by its own drive source, but also the auxiliary driving torque transmitted back from the distal interphalangeal joint 30. That is to say, compared with the fingers of a traditional dexterous hand, the drive source of this embodiment provides less main driving torque to enable the metacarpophalangeal joint 10 to rotate around the first axis X by the same angle. Thus, the tendon ligament 40 constructed in this embodiment, which spans the metacarpophalangeal joint 10, the proximal interphalangeal joint 20, and the distal interphalangeal joint 30, can reduce the driving load of the drive source of the metacarpophalangeal joint 10, thereby solving the problem of excessive load on the proximal joints (including the metacarpophalangeal joint 10 and the proximal interphalangeal joint 20) and insufficient driving capability of the distal interphalangeal joint 30 in traditional dexterous hands.
[0038] Furthermore, in this embodiment, the third reversing bearing 63 and the first reversing bearing 61 are disposed on the same side, such that the tendon cord 40 first wraps around the peripheral side of the first rope wheel 21 near the second rope wheel 31, then wraps around the peripheral side of the third reversing bearing 63, and then wraps around the peripheral side of the second rope wheel 31 near the first rope wheel 21, and the end of the tendon cord 40 is fixed to the second rope wheel 31. When the tendon cord 40 is tightened, a torsional torque rotating about the first axis X is preferentially applied to the second rope wheel 31, and then transmitted along the rigid structure of the finger to the proximal interphalangeal joint 20. The tendon cord 40 extending along the third axis Z on one side of the first rope wheel 21 applies a torsional torque bending about the first axis X to the first rope wheel 21. That is, when the distal interphalangeal joint 30 bends about the first axis, it can also drive the proximal interphalangeal joint 20 to bend about the first axis, thereby realizing the kinematic coupling between the distal interphalangeal joint 30 and the proximal interphalangeal joint 20.
[0039] The winding method of the tendon cord 40 in this embodiment can adjust the redistribution of the driving force of the tendon cord 40 among the joints, allowing the distal interphalangeal joint 30 to participate in the overall bending process, thereby significantly improving the output capacity and efficiency of the system. Moreover, since the tendon cord 40 can transmit auxiliary driving torque to the proximal interphalangeal joint 20 and the metacarpophalangeal joint 10 when it drives the distal interphalangeal joint 30 to perform palmar flexion, the present invention effectively reduces the load on the driving source in the metacarpophalangeal joint 10, thereby improving the overall efficiency of the system and extending the service life of the driving components.
[0040] Optionally, the drive source can drive the drive shaft 11 to rotate around the first axis X, for example, to drive the drive shaft 11 (i.e., the metacarpophalangeal joint 10) to perform an antipalmar flexion motion. It can also drive the drive shaft to rotate around the second axis Y, for example, to drive the drive shaft 11 (i.e., the metacarpophalangeal joint 10) to perform a lateral swing motion. The second axis Y is perpendicular to the first axis X.
[0041] It should be noted that palmar flexion refers to the bending of the fingers of the dexterous hand around the first axis X towards the side closer to the palm, such as when the dexterous hand makes a grasping motion or a fist-making motion, which is the palmar flexion around the first axis X described in the embodiments of this application.
[0042] The reversing bearing in the reversing structure 60 of this application embodiment is used to undertake the guiding and / or reversing function. Depending on the winding form of the tendon 40, the reversing structure 60 may also include more reversing bearings, not limited to the first reversing bearing 61, the second reversing bearing 62 and the third reversing bearing 63 mentioned above.
[0043] Optionally, refer to Figure 2 The dexterous hand in this embodiment of the application also includes a drive wheel 50, and the tendon rope 40 and the end away from the second rope wheel 31 are wrapped around the drive wheel 50. The drive wheel 50 is configured to be connected to a third drive source.
[0044] In this embodiment, one end of the tendon cord 40 is wound around the drive wheel 50. The drive wheel 50 is connected to the third drive source of the finger system and provides power for the extension and retraction of the tendon cord 40, thereby enhancing the driving capability of the distal interphalangeal joint 30. The drive wheel 50 also enables the finger system to have power redundancy by only needing to control the two main degrees of freedom of the metacarpophalangeal joint 10. This allows for the distribution and optimization of the tension of the tendon cord 40 under different working conditions, improving the load capacity and control flexibility of the finger system, as well as enhancing overall performance and reliability.
[0045] Optionally, refer to Figures 2-3 The end of the tendon cord 40 away from the second rope pulley 31 extends to the outside of the fingers of the dexterous hand.
[0046] In this embodiment, the power wheel 50 can be located outside the fingers of the dexterous hand, for example, it can be set inside the palm of the dexterous hand, or it can be set in other parts of the robot other than the dexterous hand. It is only necessary to reasonably set the reversing structure 60 between the power wheel 50 and the transmission shaft 11 so that the tendon rope 40 is wrapped around the circumferential side of the transmission shaft 11 away from the first rope wheel 21, thereby further optimizing the internal space layout of the robot and helping to reduce the size of the dexterous hand and the robot as a whole.
[0047] Optionally, continue to refer to Figures 2-3 The first reversing bearing 61 is located between the drive wheel 50 and the drive shaft 11, and the second reversing bearing 62 is located between the drive shaft 11 and the first pulley 21. Both the first reversing bearing 61 and the second reversing bearing 62 are located within the metacarpophalangeal joint 10 and are located on both sides of the drive shaft 11 along the second axis Y direction.
[0048] The first reversing bearing 61 and the second reversing bearing 62 are configured such that the tendons 40 on both sides of the drive shaft 11 extend along the third axis Z. The first axis X, the second axis Y, and the third axis Z are perpendicular to each other, and the third axis Z is parallel to the length direction of the fingers of the dexterous hand.
[0049] In this embodiment, the example is that the power wheel 50 is located inside the palm of the dexterous hand, and the axis of the power wheel 50 is parallel to the second axis Y.
[0050] The axes of the first reversing bearing 61 and the second reversing bearing 62 are also parallel to the first axis X. The first reversing bearing 61 enables the reversal of the tendon cord 40 between the drive wheel 50 and the drive shaft 11, while the second reversing bearing 62 guides the tendon cord 40. The tendon cord 40, extending upwards from the drive wheel 50 along the third axis Z into the metacarpophalangeal joint 10, first wraps around the upper half of the circumferential surface of the first reversing bearing 61, then extends downwards, wrapping around the circumferential surface of the drive shaft 11 on the side away from the first rope wheel 21. Next, the tendon cord 40 wraps around the circumferential surface of the second reversing bearing 62 on the side away from the drive shaft 11, ensuring stable contact between the tendon cord 40 and the circumferential surface of the drive shaft 11 on the side away from the first rope wheel 21. Finally, the tendon cord 40 extends upwards from the second reversing bearing 62 along the third axis Z, passes around the first rope wheel 21, and is fixed to the second rope wheel 31.
[0051] In this embodiment of the application, when the tendon cord 40 is pulled, the tendon cord 40 can apply a torsional torque about the first axis X to the drive shaft 11, so as to apply an auxiliary driving torque about the first axis X to the metacarpophalangeal joint 10, thereby significantly improving the dexterous hand's ability to envelop objects and grasp stability, while also reducing the drive source load of the metacarpophalangeal joint 10.
[0052] Optionally, continue to refer to Figures 2-3 The metacarpophalangeal joint 10 includes a side-swing bracket 12 rotatably mounted about a second axis Y. The side-swing bracket 12 is connected to a drive shaft 11. The second axis Y is perpendicular to the first axis X. The side-swing bracket 12 has an installation space 121 extending along the second axis Y, and a first reversing bearing 61 is located within the installation space 121.
[0053] In this embodiment, the lateral swing bracket 12 swings around the second axis Y to drive the entire finger to perform adduction / abduction movements. By creating an installation space 121 extending along the second axis Y inside the lateral swing bracket 12 and placing the first reversing bearing 61 within the installation space 121, the first reversing bearing 61 can be prevented from occupying the space along the second axis Y inside the metacarpophalangeal joint 10. This allows for a reasonable optimization of the internal space design of the metacarpophalangeal joint 10, resulting in a more compact design at the metacarpophalangeal joint 10.
[0054] Optionally, the side swing bracket 12 includes a second output wheel 123 and a first reversing wheel 122 fixed coaxially along the second axis Y. The two ends of the drive shaft 11 are connected to the first output wheel 13 and the second reversing wheel 14. The circumferential side of the first output wheel 13 meshes with the circumferential side of the first reversing wheel 122, and the circumferential side of the second output wheel 123 meshes with the circumferential side of the second reversing wheel 14.
[0055] The metacarpophalangeal joint 10 also includes a first rope group 17, a second rope group 18, a first input wheel 15 with its axis parallel to the second axis Y, and a second input wheel 16 with its axis parallel to the third axis Z. The first input wheel 15 and the second output wheel 123 are located on the upper and lower sides of the transmission shaft 11, respectively. The first rope group 17 is wound in a cross-shaped winding manner on the first input wheel 15, the first reversing wheel 122, and the first output wheel 13. The second rope group 18 is wound in a cross-shaped winding manner on the second input wheel 16, the second reversing wheel 14, and the second output wheel 123.
[0056] In this embodiment, by arranging the metacarpophalangeal joint 10 in a three-dimensional spatial layout in three dimensions, and combining the winding method of the first rope group 17 and the second rope group 18 with a flexible transmission method, the volume and weight of the metacarpophalangeal joint 10 can be effectively reduced, the integration of the metacarpophalangeal joint 10 can be improved, and it is easy to arrange in a limited space, which can meet the increasingly lightweight and highly integrated requirements of humanoid robots.
[0057] When driving the metacarpophalangeal joint 10, the rotation direction of the first input wheel 15 around the second axis Y and the rotation direction of the second input wheel 16 around the third axis Z can be controlled, thereby realizing the dual-degree-of-freedom driving and decoupling of the metacarpophalangeal joint 10 around the first axis X and the second axis Y, improving the accuracy and flexibility of joint motion control.
[0058] Reference Figures 4-6 The following details the two-degree-of-freedom decoupling mechanism of the metacarpophalangeal joint 10 in the embodiments of this application: Reference Figure 4 The first axis X and the second axis Y are perpendicular to each other and both parallel to the horizontal plane. The first axis X, along the left-right direction, is defined as the direction from right to left as a reference direction for describing the clockwise or counterclockwise rotation of the first output wheel 13 and the second reversing wheel 14 around the first axis X. The second axis Y, along the front-back direction, is defined as the direction from front to back as a reference direction for describing the clockwise or counterclockwise rotation of the first reversing wheel 122 and the second output wheel 123 around the second axis Y. The third axis Z, along the top-bottom direction, is defined as the direction from top to bottom as a reference direction for describing the clockwise or counterclockwise rotation of the second input wheel 16 around the third axis Z.
[0059] Optionally, the driving source of the aforementioned metacarpophalangeal joint 10 includes a first driving source and a second driving source.
[0060] Reference Figures 4-5The first input wheel 15 is connected to the first drive source. When the first input wheel 15 rotates clockwise around the second axis Y, the first output wheel 13 is subjected to a torsional torque that rotates counterclockwise around the first axis X through the transmission of the first rope group 17. Since the circumferential surface of the first output wheel 13 meshes with the circumferential surface of the first reversing wheel 122, the first output wheel 13 can apply a torsional torque that rotates counterclockwise around the second axis Y to the first reversing wheel 122.
[0061] Reference Figure 4 and Figure 6 The second input wheel 16 is connected to the second drive source. The axes of the second input wheel 16, the second reversing wheel 14, and the second output wheel 123 are perpendicular to each other. When the second input wheel 16 rotates clockwise around the third axis Z, the second output wheel 123 is subjected to a torsional torque rotating counterclockwise around the second axis Y through the transmission of the second rope group 18. Since the circumferential surface of the second output wheel 123 meshes with the circumferential surface of the second reversing wheel 14, the second output wheel 123 applies a torsional torque rotating clockwise around the first axis X to the second reversing wheel 14. As a result, the torsional torques around the first axis X experienced by the first output wheel 13 and the second reversing wheel 14, which are coaxially fixed along the first axis X, are opposite, thereby canceling out the torsional torques around the first axis X experienced by the transmission shaft 11. The torsional torques around the second axis Y experienced by the second output wheel 123 and the first reversing wheel 122, which are coaxially fixed along the second axis Y, are the same, thereby driving the entire finger to perform a lateral swinging motion around the second axis Y.
[0062] Similarly, refer to Figures 4-6 When the first input wheel 15 rotates clockwise and the second input wheel 16 rotates counterclockwise, the first output wheel 13 tends to rotate counterclockwise around the first axis X, the second reversing wheel 14, coaxial with the first output wheel 13, tends to rotate counterclockwise around the second axis Y, the second output wheel 123 tends to rotate clockwise around the second axis Y, and the first reversing wheel 122 tends to rotate counterclockwise around the second axis Y, thus canceling out the two forces applied to the second axis Y. This causes the first output wheel 13 and the second reversing wheel 14 to rotate around the first axis X, causing the metacarpophalangeal joint 10 to bend around the first axis X, thereby causing the entire finger to bend around the first axis X.
[0063] As can be seen, the metacarpophalangeal joint 10 of this embodiment is constructed such that, by controlling the rotation direction of the first input wheel 15 and the second input wheel 16 around their respective axes, when the torsional torque of the first output wheel 13 around the first axis X is in the same direction as the torsional torque of the second reversing wheel 14 around the first axis X, the torsional torque of the first reversing wheel 122 and the second output wheel 123 around the second axis Y is in opposite directions, thereby driving the metacarpophalangeal joint 10 to rotate around the first axis X. Similarly, by controlling the rotation direction of the first input wheel 15 and the second input wheel 16 around their respective axes, when the torsional torque of the second output wheel 123 and the first reversing wheel 122 around the second axis Y is in the same direction, the torsional torque of the first output wheel 13 and the second reversing wheel 14 around the first axis X is in opposite directions, thereby driving the metacarpophalangeal joint 10 to rotate around the second axis Y.
[0064] In this embodiment, the drive of the metacarpophalangeal joint 10 has a clear motion mapping relationship, which makes it easy for the control system to quickly output the corresponding drive signal to the first input wheel 15 and the second input wheel 16 after receiving the electrical signal that causes the joint to move around a certain degree of freedom, so as to drive the corresponding joint to rotate around the first axis X or around the second axis Y, thereby improving the response speed when the joint moves.
[0065] Optionally, continue to refer to Figures 4-6 The first rope group 17 includes a first rope 171 and a second rope 172. The two ends of the first rope 171 and the second rope 172 are fixed to the first input wheel 15 and the first output wheel 13, respectively. The first rope 171 and the second rope 172 cross between the first input wheel 15 and the first reversing wheel 122 to form a figure-eight winding; they also cross between the first reversing wheel 122 and the first output wheel 13 to form a figure-eight winding.
[0066] The second rope group 18 includes a third rope 181 and a fourth rope 182. The two ends of the third rope 181 and the fourth rope 182 are fixed to the second input wheel 16 and the second output wheel 123, respectively. The third rope 181 and the fourth rope 182 cross between the second input wheel 16 and the second reversing wheel 14 to form a figure-eight winding. They also cross between the second reversing wheel 14 and the second output wheel 123 to form a figure-eight winding.
[0067] Optionally, the side swing bracket 12 also includes a bracket body 124, with the second output wheel 123 disposed on one side of the bracket body 124, and the first reversing wheel 122 disposed on the side of the second output wheel 123 away from the bracket body 124. Thus, the bracket body 124 can provide stable support for the second output wheel 123 and the first reversing wheel 122.
[0068] Optionally, the side swing bracket 12 is an integral structure, which can further reduce the assembly space between the bracket body 124, the second output wheel 123, and the first reversing wheel 122, thus helping to reduce the overall volume of the metacarpophalangeal joint 10. The diameter of the first reversing wheel 122 is smaller than the diameter of the second output wheel 123. A first through hole extending along the second axis Y and penetrating the side swing bracket 12 is opened at the center of the side swing bracket 12. The first through hole forms the aforementioned mounting space 121 for placing the first reversing bearing 61.
[0069] Optionally, refer to Figures 3-6 The side swing bracket 12 also has a second through hole that communicates with the installation space 121 and allows the tendon rope 40 to pass through. The second through hole extends along the third axis Z.
[0070] Optionally, refer to Figures 2-4 The side swing bracket 12 is connected to the drive shaft 11 via the first joint bracket, and the second input wheel 16 is connected to the drive shaft 11 via the second joint bracket 19 set along the third axis Z, so that the second input wheel 16, the first output wheel 13, and the second reversing wheel 14 can rotate synchronously around the first axis X.
[0071] Optionally, refer to Figure 3 The second reversing bearing 62 is rotatably connected to the second joint bracket 19.
[0072] In this embodiment, the second reversing bearing 62 is rotatably connected to the second joint bracket 19, which allows both the first reversing bearing 61 and the second reversing bearing 62 to be located in the space inside the metacarpophalangeal joint 10. This can reasonably optimize the internal space design of the metacarpophalangeal joint 10, so as to achieve a more compact design at the metacarpophalangeal joint 10, thereby significantly reducing the volume of the fingers of the dexterous hand.
[0073] Optionally, refer to Figures 3-4 The second joint support 19 includes an extension 191 located on the side away from the side swing support 12 and extending along the second axis Y. The second reversing bearing 62 is rotatably connected to the extension 191. The extension 191 includes two oppositely arranged along the first axis X, and the second reversing bearing 62 is rotatably disposed between the two extensions 191.
[0074] Optionally, refer to Figures 7-8 The proximal interphalangeal joint 20 also includes a fixing bracket 22 coaxially fixed with the first rope pulley 21, and the distal interphalangeal joint 30 also includes a fixing wheel 32 coaxially fixed with the second rope pulley 31.
[0075] The fingers of the dexterous hand also include a third rope group 70, which includes a fifth rope 71 and a sixth rope 72. The fifth rope 71 and the sixth rope 72 are intertwined in a cross shape between the fixed bracket 22 and the fixed wheel 32, and are configured to achieve kinematic coupling between the proximal finger joint 20 and the distal finger joint 30.
[0076] In this embodiment, the fifth rope 71 and the sixth rope 72 are both of fixed length, and their ends are fixed to the fixed bracket 22 and the fixed wheel 32, respectively. The fifth rope 71 and the sixth rope 72 are wrapped in a figure-eight shape between the fixed bracket 22 and the fixed wheel 32. When the tendon rope 40 is pulled to drive the second rope wheel 31 to perform a palm-to-palm bending motion around the first axis X, one of the transmission ropes, such as the fifth rope 71, gradually winds up and wraps around the fixed wheel 32, thereby pulling the fixed bracket 22 and the first rope wheel 21 to also bend around the first axis X, thereby causing the sixth rope 72 to gradually unwind and wrap around the fixed bracket 22.
[0077] In this embodiment, the proximal finger joint 20 and the distal finger joint 30 are coupled in a figure-eight motion using the third rope assembly 70. Simply driving the distal finger joint 30 initiates a movement that drives the proximal finger joint 20, enabling synchronous bending and rotation of the distal and proximal finger joints 30 at the same angle. This facilitates control and ensures reliable transmission. Furthermore, when performing actions such as clenching a fist or grasping an object, the distal finger joint 30, proximal finger joint 20, and metacarpophalangeal joint 10 can be linked together, significantly improving the dexterity of the fingers 1 in enveloping objects and enhancing grip stability.
[0078] Optionally, refer to Figure 7 The fifth rope 71 is wound in an S-shape between the fixed bracket 22 and the fixed wheel 32 located on the first side of the first rope wheel 21, and the sixth rope 72 is wound in an S-shape between the fixed bracket 22 and the fixed wheel 32 located on the second side of the first rope wheel 21.
[0079] In this embodiment, by distributing the fifth rope 71 and the sixth rope 72 on both sides of the finger, it is possible to ensure that the force inside the distal finger joint 30 and the proximal finger joint 20 is uniform.
[0080] Optionally, refer to Figure 8 A fixed bracket 22 is provided on each side of the first rope pulley 21, and the two fixed brackets 22 and the first rope pulley 21 are coaxially fixed through a first rotating shaft 23. A fixed wheel 32 is provided on each side of the second rope pulley 31, and the two fixed wheels 32 and the second rope pulley 31 are coaxially fixed through a second rotating shaft 33.
[0081] Optionally, the dexterous hand in this embodiment further includes a reset structure 80. The reset structure 80 is disposed between the proximal interphalangeal joint 20 and the metacarpophalangeal joint 10, and is configured to extend and retract along the length of the fingers of the dexterous hand. This allows the distal interphalangeal joint 30 and the proximal interphalangeal joint 20 to reset when the third drive source stops inputting power to the power wheel 50. This embodiment only uses a torsion spring as an example for illustration.
[0082] Based on the same inventive concept, this application also provides a dexterous hand, including the fingers of the dexterous hand described above.
[0083] The dexterous hand in the embodiments of this application includes all the beneficial effects of the fingers of the dexterous hand described above, which will not be repeated here.
[0084] Based on the same inventive concept, this application provides a robot that includes the fingers of the dexterous hand described in the above embodiments.
[0085] The robot in this embodiment also includes a robotic arm connected to the palm of the dexterous hand. The drive wheel 50 can also be installed within the robotic arm as needed, thereby extending the length of the tendon cable 40 and rationally configuring the reversing structure 60 between the tendon cable 40 and the drive shaft 11 within the metacarpophalangeal joint 10. This allows the distal interphalangeal joint 30 of the finger to bend, which in turn causes the proximal interphalangeal joint 20 to bend synchronously and at the same angle as the distal interphalangeal joint 30. This enables more precise adjustment of the finger bending motion and allows for a tighter grip on target objects, improving the dexterous hand's gripping ability.
[0086] The beneficial technical effects of the technical solutions provided in this application include: This embodiment of the application forms a continuous drive path within the fingers of a dexterous hand, spanning the metacarpophalangeal joint 10, proximal interphalangeal joint 20, and distal interphalangeal joint 30. This drive configuration creates a large wrap angle between the distal interphalangeal joint 30 and the proximal interphalangeal joint 20, allowing the distal interphalangeal joint 30 to participate in the overall drive process. Furthermore, the effective radius of action at the distal and proximal interphalangeal joints 30 is greater than that at the metacarpophalangeal joint 10, resulting in a higher torque output capability at the distal end of the tendon cord 40. This enables the active and rational distribution of driving torque among the joints. Moreover, the tendon cord 40 simultaneously bypasses the drive shaft 11 of the metacarpophalangeal joint 10. When the tendon cord 40 tightens, a torsional torque is preferentially generated at the distal interphalangeal joint 30, bending around the first axis X. This torque is then transmitted proximally through the rigid structure of the finger, creating an auxiliary driving torque at the metacarpophalangeal joint 10. This causes the metacarpophalangeal joint 10 to also bend around the first axis X, effectively enhancing the gripping ability of the fingers. The auxiliary driving torque generated at the metacarpophalangeal joint 10 can effectively reduce the load on the two driving sources at the metacarpophalangeal joint 10, improve the overall system efficiency and extend the service life of the driving components.
[0087] In this embodiment, the drive wheel 50 is configured as a third drive source connecting the robot system, forming a three-input drive structure. This allows the finger system to have drive redundancy while only needing to control two main degrees of freedom. This enables the distribution and optimization of tension on each tendon 40 under different working conditions, improving the system's load capacity and control flexibility. It also allows for better drive strategies under complex conditions, thereby improving system robustness and adaptability.
[0088] In this embodiment, the highly integrated structure of the metacarpophalangeal joint 10 enables multi-degree-of-freedom actuation of the fingers to be realized in a limited space, which helps to improve the integration and power density of the dexterous hand system.
[0089] In the description of this application, the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate directions or positional relationships based on the exemplary directions or positional relationships shown in the accompanying drawings. They are used to facilitate the description or simplification of the embodiments of this application and are not intended to indicate or imply that the device or component referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0090] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0091] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.
[0092] The above description is only a partial implementation of this application. It should be noted that for those skilled in the art, other similar implementation methods based on the technical concept of this application, without departing from the technical concept of this application, also fall within the protection scope of the embodiments of this application.
Claims
1. A finger of a dexterous hand, characterized in that, include: The device includes a metacarpophalangeal joint, a proximal interphalangeal joint, and a distal interphalangeal joint. The metacarpophalangeal joint includes a drive shaft, the proximal interphalangeal joint includes a first rope pulley, and the distal interphalangeal joint includes a second rope pulley. The axes of the drive shaft, the first rope pulley, and the second rope pulley are all parallel to a first shaft. The radius of the drive shaft is smaller than the radius of the first rope pulley and the radius of the second rope pulley. The drive source is configured to at least drive the drive shaft to rotate about the first axis; The reversing structure includes at least a first reversing bearing, a second reversing bearing located between the drive shaft and the first sheave, and a third reversing bearing located between the first sheave and the second sheave; The tendon cord sequentially passes around the first reversing bearing, the peripheral side of the drive shaft away from the first rope wheel, the second reversing bearing, the peripheral side of the first rope wheel near the second rope wheel, the third reversing bearing, and the peripheral side of the second rope wheel near the first rope wheel, and is fixedly connected to the second rope wheel; the tendon cord is configured to apply an auxiliary driving torque about the first axis to the drive shaft when it drives the distal finger joint to rotate about the first axis.
2. The fingers of a dexterous hand according to claim 1, characterized in that, It also includes a drive wheel, with the tendon rope wound around the end away from the second pulley, and the drive wheel is configured to be connected to a third drive source.
3. The fingers of a dexterous hand according to claim 2, characterized in that, The end of the tendon cord away from the second pulley extends to the outside of the fingers of the dexterous hand.
4. The fingers of a dexterous hand according to claim 2, characterized in that, The first reversing bearing is located between the drive wheel and the transmission shaft; both the first reversing bearing and the second reversing bearing are located within the metacarpophalangeal joint and on both sides of the transmission shaft along the second axis. The first reversing bearing and the second reversing bearing are configured such that the tendons on both sides of the drive shaft extend along the third axis, the first axis, the second axis and the third axis are perpendicular to each other, and the third axis is parallel to the length direction of the fingers of the dexterous hand.
5. The fingers of a dexterous hand according to claim 4, characterized in that, The metacarpophalangeal joint includes a side-swing bracket that is rotatably mounted around a second axis, and the side-swing bracket is connected to the drive shaft; The side swing bracket has an installation space extending along the second axis, and the first reversing bearing is located within the installation space.
6. The fingers of a dexterous hand according to claim 5, characterized in that, The side swing bracket includes a second output wheel and a first reversing wheel fixed coaxially along a second axis. The two ends of the drive shaft are connected to the first output wheel and the second reversing wheel. The circumferential side of the first output wheel meshes with the circumferential side of the first reversing wheel, and the circumferential side of the second output wheel meshes with the circumferential side of the second reversing wheel. The metacarpophalangeal joint also includes a first rope group, a second rope group, a first input wheel with its axis parallel to a second shaft, and a second input wheel with its axis parallel to a third shaft. The first input wheel and the second output wheel are located on the upper and lower sides of the transmission shaft, respectively. The first rope group is wound sequentially on the first input wheel, the first reversing wheel, and the first output wheel in a crisscross pattern. The second rope group is wound sequentially on the second input wheel, the second reversing wheel, and the second output wheel in a crisscross pattern. The second input wheel is connected to the drive shaft via the second joint bracket, and the second reversing bearing is rotatably connected to the second joint bracket.
7. The fingers of a dexterous hand according to claim 6, characterized in that, The drive source includes a first drive source and a second drive source, the first input wheel is connected to the first drive source, and the second input wheel is connected to the second drive source; When the torsional torque on the first output wheel around the first axis is in the same direction as the torsional torque on the second reversing wheel around the first axis, the metacarpophalangeal joint rotates around the first axis; when the torsional torques on the second output wheel and the first reversing wheel around the second axis are in the same direction, the metacarpophalangeal joint rotates around the second axis.
8. The fingers of a dexterous hand according to claim 1, characterized in that, The proximal interphalangeal joint also includes a fixing bracket coaxially fixed with the first rope wheel, and the distal interphalangeal joint also includes a fixing wheel coaxially fixed with the second rope wheel; The fingers of the dexterous hand also include a third rope group, which includes a fifth rope and a sixth rope; the fifth rope and the sixth rope are intertwined in a cross shape between the fixed bracket and the fixed wheel, and are configured to achieve kinematic coupling between the proximal finger joint and the distal finger joint.
9. The fingers of a dexterous hand according to claim 8, characterized in that, The fifth rope is wound in an S-shape between the fixed bracket and the fixed wheel located on the first side of the first rope wheel, and the sixth rope is wound in an S-shape between the fixed bracket and the fixed wheel located on the second side of the first rope wheel.
10. The fingers of a dexterous hand according to claim 1, characterized in that, It also includes a reset structure disposed between the proximal interphalangeal joint and the metacarpophalangeal joint, configured to extend and retract along the length of the fingers of the dexterous hand.
11. A dexterous hand, characterized in that, Including the fingers of a dexterous hand as described in any one of claims 1-10.
12. A robot, characterized in that, Including the fingers of a dexterous hand as described in any one of claims 1-10.