A humanoid finger and a humanoid hand based on tendon and link hybrid transmission

Abstract

The application relates to the technical field of design and manufacturing of dexterous hands, and provides a humanoid finger and a humanoid hand based on tendon and connecting rod hybrid transmission. The humanoid finger comprises a driving mechanism, a connecting rod structure, a plurality of tendons, a rebound mechanism, a DIP knuckle, a PIP knuckle, an MCP knuckle and an MCP_Bottom knuckle in the direction from a fingertip to a palm. The finger has high human-likeness and dexterity, which is embodied in the finger knuckle length and the finger joint freedom degree; the fingertip is provided with a mounting position of an FSR so as to provide force feedback for the finger. The pre-tightening mechanism realizes a convenient tendon pre-tightening mode while guaranteeing the miniaturization of the finger. The MCP joint decoupling method realizes the decoupling of the MCP joint flexion / extension freedom degree and the MCP joint adduction / abduction freedom degree of the fully-driven finger by using different transmission modes, so that the humanoid hand can perform various dexterous operations.

Description

Technical Field

[0001] This invention relates to the field of dexterous hand design and manufacturing technology, and in particular to an anthropomorphic finger and an anthropomorphic hand based on a hybrid transmission of tendons and links. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Human fingers refer to the five branches at the front of the hand, mainly including the thumb, index finger, middle finger, ring finger, and little finger. Each of the four fingers (excluding the thumb) has three joints: the distal interphalangeal joint (DIP), the proximal interphalangeal joint (PIP), and the metacarpophalangeal joint (MCP). The thumb, composed of only two phalanges, has only one interphalangeal joint (IP) and one MCP joint. The MCP joint is formed by the metacarpal head and the base of the proximal phalanx. The joint capsule is thin and loose, reinforced anteriorly and posteriorly by ligaments. The palmar ligaments are relatively strong and contain fibrocartilaginous endplates. Lateral collateral ligaments attach from the sides of the metacarpal heads downwards to the bases of the phalanges; these ligaments are taut during finger flexion and relaxed during finger extension. When the finger is in extension, the metacarpophalangeal joint can perform flexion, extension, adduction, abduction, and circumduction movements. Circumduction is limited by the ligaments. When the fingers are in a flexed position, only flexion and extension movements are allowed. Except for the MCP joint, the other finger joints are formed by the bases of the two adjacent phalanges and the trochlea, making them typical trochlear joints. The joint capsule is loose, reinforced by ligaments on both sides, allowing only flexion and extension movements. It is generally believed that the DIP and PIP joints of the human finger each have one degree of flexion / extension freedom, while the MCP joint has two degrees of freedom: flexion / extension and adduction / abduction. Furthermore, the movements of the DIP and PIP joints in the human hand are coupled; that is, the DIP joint moves in sync with the PIP joint, rather than moving independently. Biological research has found that the ratio of the rotation angles of the DIP and PIP joints during flexion movements in the human finger is approximately 1:1.

[0004] To achieve functions similar to a human hand, current prosthetic hands primarily utilize various transmission methods, including chord drives, linkage drives, gear drives, and worm gear drives. Among these, gear and worm gear transmission mechanisms are gradually being phased out due to their large size, weight, and inflexible movement. Chord drives, mimicking animal tendons, provide a degree of flexibility and grasping adaptability for finger movement, offering significant advantages in safety. Furthermore, chord drives enable long-distance transmission, facilitating the integration of actuators into the palm or arm, greatly reducing the weight and inertia of the prosthetic hand and thus lowering power consumption. Additionally, chord drives allow for better integration into traditional mechanical structures while maintaining a lightweight prosthetic hand. Therefore, chord-driven prosthetic hands have become a research hotspot for many scholars both domestically and internationally.

[0005] For example, the dexterous robotic hands developed by Harvard University and Stanford University, the four-finger dexterous robotic hand proposed by Mizushima et al. of the University of Tokyo, the hands of the MELTANT-α humanoid robot released by the Japanese company Meltin MMI, the highly biomimetic and highly integrated biomimetic dexterous hand developed by SCHUNK in Germany, the SHU-Ⅱ hand developed by Shanghai University, the F-hand dexterous hand developed by DoubleGiken in Japan, and the Tactile Telerobot dexterous robotic hand developed by ANA in Japan all adopt the tendon rope transmission method.

[0006] However, the reliability of dexterous finger movements requires the chords to be constantly taut during operation. When the chords slack, transmission errors, or gaps, occur in the chord drive system, affecting the accuracy of dexterous finger movements. The chords in chord-driven dexterous fingers can slack during installation and long-term use; therefore, it is necessary to design a reasonable pre-tensioning mechanism to ensure the chords are always taut, achieving effective transmission to each finger joint. Furthermore, in fully driven prosthetic hands, because the actuators of the chord-driven manipulator are integrated into the palm or arm, motion coupling occurs when the drive chords of the rear joints pass through the front joints. Although underactuation can avoid this coupling, the reduction in active degrees of freedom significantly decreases the dexterity of the prosthetic hand. Therefore, it is necessary to design suitable mechanisms to achieve motion decoupling between joints.

[0007] The inventors discovered that current methods for pre-tensioning rope-driven dexterous fingers are mostly complex and difficult to implement, posing a challenge to the limited internal space of the prosthetic hand and hindering finger miniaturization. Furthermore, most pre-tensioning methods require disassembling and reassembling the dexterous finger during the pre-tensioning process, making it complex and inconvenient to use. Secondly, most current decoupling methods require the addition of other mechanical structures, such as rope pulleys, to achieve decoupling. However, due to the limited space in the prosthetic hand, adding other mechanical structures is difficult and would increase the weight and size of the prosthetic hand, resulting in a bulky prosthetic hand and reducing the user experience. Additionally, most current decoupling methods focus on the decoupling of the DIP and PIP joints of the fingers, i.e., the decoupling between flexion / extension degrees of freedom, while rarely addressing the decoupling of the MCP joint, i.e., the decoupling between flexion / extension degrees of freedom and adduction / abduction degrees of freedom. Summary of the Invention

[0008] To address the technical problems mentioned above, this invention provides a humanoid finger and hand based on a hybrid transmission system of tendon ligaments and linkages. To ensure the humanoid nature of the finger, the DIP and PIP joints are underactuated, with a single actuator, a rebound mechanism, and tendon ligament transmission enabling flexion / extension freedom of movement. The MCP joint is fully actuated, with its flexion / extension and adduction / abduction freedoms driven by two separate actuators. The length of each phalanx is designed to be rounded based on the average length of the joints of a male index finger. Furthermore, a thin-film pressure sensor (FSR) mounting location is provided at the fingertip, providing a foundation for closed-loop control of force-tactile feedback and slip detection. The designed miniature tendon ligament pretensioning mechanism is installed within the DIP phalanx, allowing for tendon ligament tensioning without disassembling the finger. The proposed MCP joint decoupling method first divides the human hand's MCP joint into two parts: the MCP joint itself and the MCP_Bottom joint. Then, a single actuator, a rebound mechanism, and a tendon cable transmission method are used to achieve the flexion / extension degrees of freedom of the finger's MCP joint, while a single actuator and a linkage transmission method are used to achieve the adduction / abduction degrees of freedom. The tendon cable passes through the extension line of the center of the rotation axis for the adduction / abduction degrees of freedom. The two transmission methods do not affect each other, thus achieving decoupling of the MCP joint. This proposed decoupling method requires no additional mechanical structures and, while maintaining the dexterity of the prosthetic finger, does not affect its size or weight.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] The first aspect of the present invention provides an anthropomorphic finger based on a hybrid transmission of tendons and links.

[0011] A humanoid finger based on a hybrid transmission of tendons and links includes: a drive mechanism, a link structure, several tendons, a rebound mechanism, and DIP, PIP, MCP, and MCP_Bottom phalanges along the fingertip to palm direction. The DIP and PIP phalanges, the PIP and MCP phalanges, and the MCP and MCP_Bottom phalanges are all connected by the rebound mechanism. The MCP_Bottom phalange is mounted on the palm. One end of the link structure is connected to the drive mechanism, and the other end is connected to the MCP_Bottom phalange. The two ends of the different tendons are connected to different phalanges and the drive mechanism of the drive phalanges.

[0012] Furthermore, the drive mechanism includes a first motor installed in the MCP knuckle, a second motor installed on opposite sides of the palm, and a third motor.

[0013] Furthermore, the different tendon cords are connected at both ends to different phalanges and drive mechanisms for driving the phalanges, specifically as follows: one end of the first tendon cord is connected to the DIP phalanx, and the other end is connected to the first motor; one end of the second tendon cord is connected to the bottom of the MCP phalanx, and the other end is connected to the second motor. The first motor is used to provide power for the flexion / extension movement of the DIP and PIP phalanges, and the second motor is used to provide power for the flexion / extension movement of the MCP phalanx.

[0014] Furthermore, the linkage structure adopts a parallelogram structure, including a first link, a second link, and a third link connected to the output shaft of the third motor. One end of the first link and the second link are respectively connected to the third link, and the other end are respectively connected to the MCP_Bottom knuckle. Under the rotation of the third motor, the linkage structure is used to provide power for the adduction / abduction movement of the human hand's MCP knuckle.

[0015] Furthermore, the second tendon cord passes through the extension line of the center of the adduction / abduction rotation axis.

[0016] Furthermore, the human hand MCP knuckle is composed of the MCP knuckle and the MCP_Bottom knuckle.

[0017] Furthermore, the front end of the DIP knuckle has a reserved mounting position for an FSR, which is used for force feedback control of the humanoid finger.

[0018] Furthermore, the anthropomorphic finger also includes a pre-tensioning mechanism integrated within the DIP knuckle for tensioning loose tendons.

[0019] Furthermore, the rebound mechanism includes a spring that cooperates with the tendon cord to complete the flexion / extension movement of the relevant phalanx.

[0020] A second aspect of the invention provides an anthropomorphic hand based on a hybrid transmission of tendons and links.

[0021] A humanoid hand based on a hybrid tendon and link transmission includes a palm and a thumb, index finger, middle finger, ring finger and little finger mounted on the palm. The index finger, middle finger, ring finger and little finger all adopt the humanoid finger based on a hybrid tendon and link transmission as described in the first aspect. The thumb, based on the humanoid finger, abandons the MCP_Bottom joint.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] 1. The finger joints described in this invention are designed based on the average length of each joint of a male index finger, rounded to the nearest whole number. The DIP joint and PIP joint are coupled in motion, and the angle ratio between the two is close to 1:1, which ensures the human-like nature of the dexterous fingers.

[0024] 2. The fingertip of the finger described in this invention has a reserved installation position for FSR, which can be used to measure the fingertip force of the dexterous hand in the later stage, so as to realize force feedback control of the dexterous hand, etc.

[0025] 3. The pre-tensioning mechanism described in this invention is small in size and simple to implement. It can be integrated into the DIP knuckle of the finger, effectively saving internal space in the finger. Furthermore, the pre-tensioning mechanism described in this invention is convenient to use, allowing for pre-tensioning of the tendons and ligaments without disassembling the finger.

[0026] 4. The finger MCP joint decoupling method based on tendon cord and linkage hybrid transmission described in this invention realizes the movement of the finger MCP joint in a fully driven manner. The flexion / extension and adduction / abduction movements of the MCP joint are driven by independent actuators, which enables the prosthetic hand to complete a variety of complex hand gestures, not just grasping movements, thus improving the anthropomorphism and dexterity of the prosthetic hand.

[0027] 5. The finger MCP joint decoupling method based on the hybrid transmission of tendon cord and connecting rod described in this invention can solve the coupling problem of the two degrees of freedom of the finger MCP joint without adding additional mechanical structures, and effectively control the size and weight of the prosthetic hand. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0029] Figure 1 This is a front view of the human-like finger structure proposed in this invention;

[0030] Figure 2 This is a rear view of the human-like finger structure proposed in this invention;

[0031] Figure 3 This is a right view of the human-like finger structure proposed in this invention;

[0032] Figure 4 This is an exploded view of the human finger-like DIP structure proposed in this invention;

[0033] Figure 5 This is a schematic diagram of the humanoid finger MCP structure proposed in this invention;

[0034] Figure 6 This is a schematic diagram of the human finger motor pulley structure proposed in this invention;

[0035] Figure 7 This is a rear view of the leftward swing motion of the humanoid finger MCP joint proposed in this invention;

[0036] Figure 8 This is a schematic diagram of the decoupling principle of the humanoid finger MCP joint proposed in this invention;

[0037] Figure 9 This is a front view of the human hand-like design proposed in this invention;

[0038] Figure 10 This is a schematic diagram of the human-like finger grasping a spherical object proposed in this invention.

[0039] The components are as follows: 1. DIP knuckle; 2. FSR mounting position; 3. Spring No. 1; 4. Male screw No. 1; 5. Female screw No. 1; 6. Preload screw; 7. Preload pulley; 8. Nut insert No. 1; 9. Nut insert No. 2; 10. Tendon rope No. 1; 11. Tendon rope clip No. 1; 12. PIP knuckle; 13. Spring No. 2; 14. Male screw No. 2; 15. Female screw No. 2; 16. MCP knuckle; 17. Spring No. 3; 18. Male screw No. 3; 19. Female screw No. 3; 20. Motor No. 1; 21. Motor pulley No. 1; 22. Motor pulley fixing screw No. 1; 23. Motor fixing component; 24. Motor fixing nut. 25. Motor fixing screw; 26. No. 2 tendon rope clip; 27. No. 2 tendon rope; 28. No. 4 male nail; 29. ​​No. 4 female nail; 30. No. 3 tendon rope clip; 31. No. 2 motor; 32. No. 2 motor pulley; 33. No. 2 motor pulley fixing screw; 34. No. 4 tendon rope clip; 35. MCP_Bottom knuckle; 36. No. 1 rod; 37. No. 2 rod; 38. No. 3 rod; 39. Rod fixing nut; 40. Rod fixing screw; 41. No. 3 motor; 42. No. 3 rod fixing screw; 43. Palm; 44. Reversing rod; 45. Thumb; 46. Index finger; 47. Middle finger; 48. Ring finger; 49. Little finger. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0041] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0042] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0043] In this invention, terms such as "upper," "lower," "left," "right," "front," "back," "vertical," "horizontal," "side," and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only to facilitate the description of the structural relationships of the various components or elements of this invention and do not specifically refer to any component or element in this invention. They should not be construed as limiting the invention.

[0044] In this invention, terms such as "fixed connection," "connected," and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0045] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0046] Example 1

[0047] This embodiment introduces a humanoid finger based on a hybrid transmission of tendon cords and linkages, including: finger DIP knuckle, finger PIP knuckle, finger MCP knuckle, finger MCP_Bottom knuckle, pretensioning mechanism, linkage structure, drive mechanism, tendon cord, rebound mechanism, etc.

[0048] The lengths of the DIP, PIP, and MCP knuckles are designed based on the average length of the joints of a male index finger, rounded to the nearest whole number, and are 25mm, 22mm, and 47mm respectively. The connection between the DIP and PIP knuckles is the DIP joint; the connection between the PIP and MCP knuckles is the PIP joint; the connection between the MCP and MCP_Bottom knuckles is the MCP joint; and the connection between the MCP_Bottom knuckle and the palm is the MCP_Bottom joint. Additionally, the front end of the DIP knuckle has a pre-installed mounting position for a Force Feedback System (FSR), facilitating force feedback control of the finger.

[0049] The MCP phalanges and MCP_Bottom phalanges of the fingers together constitute the MCP phalanges of the human hand, realizing the function of the MCP joints in the human hand. Among them, the MCP joints of the fingers are mainly used to realize the flexion / extension function of the MCP joints in the human hand; the MCP_Bottom joints of the fingers are mainly used to realize the adduction / abduction function of the MCP joints in the human hand.

[0050] The finger's MCP_Bottom phalanx connects to the palm, forming the finger's MCP_Bottom joint, and serves as the base for finger mounting.

[0051] The pretensioning mechanism mainly consists of three parts: a pretensioning pulley, a screw, and a nut insert. The pretensioning mechanism is integrated within the finger's DIP knuckle. The rotation of the screw drives the rotation of the pretensioning pulley, thereby tensioning any loose tendons. The nut insert primarily serves to secure the screw.

[0052] The linkage structure is a parallelogram structure, mainly including: link 1, link 2, and link 3 connected to the output shaft of the driver. One end of link 1 and link 2 is connected to link 3, and the other end is connected to the MCP_Bottom knuckle of the finger. In this way, link 1, link 2, link 3, and the lower end of the MCP_Bottom knuckle of the finger can form a parallelogram-like structure. With the rotation of the driver, the adduction / abduction movement of the human hand's MCP joint is realized.

[0053] The drive mechanism mainly comprises two parts: a driver and a driver pulley connected to the driver. For the movement of the finger DIP and PIP joints, the drive mechanism is integrated within the finger MCP knuckle. For the movement of the finger MCP and MCP_Bottom joints, the drive mechanism is mounted within the palm to save space in the dexterous hand. As an optional implementation, a motor can be selected as the driver, and motors of various sizes and models can be selected.

[0054] One portion of the tendon cord is fixed at one end to a pre-tensioning pulley integrated within the finger's DIP joint, and at the other end to a drive pulley on a driver installed within the finger's MCP joint. This transmits the drive's rotational power to the finger's DIP and PIP joints, enabling flexion / extension movements. Tension of this portion of the tendon cord can be achieved either through the proposed pre-tensioning mechanism or by the rotation of a motor. The other portion of the tendon cord is connected at one end to the bottom of the finger's MCP joint via a tendon cord clip, passing through the center of the pivot point for the finger's MCP joint's adduction / abduction movements or its extension. The other end is connected to a drive pulley on a driver fixed within the palm. With the rotation of the driver, flexion / extension movements of the hand's MCP joint are achieved. Tension of this portion of the tendon cord can be achieved by the rotation of a motor. The tendon cord is made of a rigid material and is not easily deformed when stretched by the drive mechanism. As an optional embodiment, a steel wire rope can be used as the tendon cord. As an optional embodiment, an aluminum sleeve can be used for the tendon cord clip for fixation.

[0055] The rebound mechanism, in conjunction with the tendon ligament, enables flexion / extension movements of the DIP, PIP, and MCP joints of the fingers. As an optional implementation, a torsion spring can be selected as the finger's rebound mechanism to achieve rotation after flexion / extension. Since the ratio between the two joint angles of the DIP and PIP joints is approximately 1:1, identical torsion springs can be selected for these two joints. For the MCP joint, torsion springs with different torques can be selected.

[0056] The finger proposed in this invention can achieve a 1:1 coupled motion of the DIP joint rotation and PIP joint rotation, as well as flexion / extension and adduction / abduction movements of the MCP joint, exhibiting a high degree of biomimicry. A force feedback mechanism (FSR) can be installed at the fingertip to achieve force feedback control of the prosthetic hand. The proposed pretensioning mechanism can be integrated into the finger's DIP joint, resulting in a small size and convenient use. The proposed decoupling method can decouple the flexion / extension and adduction / abduction degrees of freedom of the fully driven finger's MCP joint, allowing the prosthetic hand to perform a variety of operations like a human hand without increasing its size and weight.

[0057] The following is a more detailed description of this embodiment with reference to the accompanying drawings:

[0058] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5The diagram shows a humanoid finger structure based on a hybrid transmission of tendon cords and linkages, including: DIP knuckle 1, FSR mounting position 2, spring 1 3, male pin 1, female pin 1 5, preload screw 6, preload pulley 7, nut insert 1 8, nut insert 2 9, tendon cord 10, tendon cord clip 11, PIP knuckle 12, spring 2 13, male pin 2 14, female pin 2 15, MCP knuckle 16, spring 3 17, male pin 3 18, female pin 3 19, motor 1 20, motor pulley 21, and so on. 22. Motor rope pulley fixing screw; 23. Motor fixing component; 24. Motor fixing nut; 25. Motor fixing screw; 26. No. 2 tendon rope clip; 27. No. 4 male nail; 28. No. 4 female nail; 29. ​​No. 3 tendon rope clip; 30. No. 2 motor; 31. No. 2 motor rope pulley; 32. No. 2 motor rope pulley fixing screw; 33. No. 4 tendon rope clip; 34. MCP_Bottom knuckle; 35. No. 1 rod; 36. No. 2 rod; 37. No. 3 rod; 38. Rod fixing nut; 39. Rod fixing screw; 40. No. 3 motor; 41. No. 3 rod fixing screw; 42. Hand; 43. Reversing rod; 44.

[0059] Each phalanx is connected to the others via pins and springs, ensuring normal rotation after joint flexion / extension. Specifically, DIP phalanx 1 and PIP phalanx 12 are connected via spring 3, male pin 4, and female pin 5; PIP phalanx 12 and MCP phalanx 16 are connected via spring 13, male pin 14, and female pin 15; MCP phalanx 16 and MCP_Bottom phalanx 35 are connected via spring 17, male pin 18, and female pin 19. The connection between MCP_Bottom phalanx 35 and the palm 43 is directly via male pin 28 and female pin 29, ensuring lateral rotation of the MCP joint. If an FSR is to be installed on the finger, it can be fixed at FSR installation position 2 to provide force-tactile information to the prosthetic hand.

[0060] The tendon ligaments are inserted into each finger joint, transmitting the driving force of the motor to each finger joint. One end of tendon ligament 10 is connected to DIP finger joint 1 via tendon ligament clip 11 on pretension pulley 7, and the other end is connected to motor 20 via tendon ligament clip 26 on motor pulley 21. A reversing lever 44 changes direction along the way; the reversing lever 44 and MCP finger joint 16 are integrated. One end of tendon ligament 27 is fixed to the bottom of MCP finger joint 16 via tendon ligament clip 30, and the other end is connected to motor 31 via tendon ligament clip 34 on motor pulley 32.

[0061] Motor 1 (20) is fixed to the MCP knuckle 16 via motor mounting bracket 23, motor mounting nut 24, and motor mounting screw 25, providing power for the flexion / extension movements of DIP knuckle 1 and PIP knuckle 12. Motors 2 (31) and 3 (41) are fixed to the palm 43 via a special structure, ensuring the stability of the motor body during rotation and preventing displacement due to external forces, thus affecting the flexion / extension accuracy of the fingers. They provide power for the flexion / extension movements of MCP knuckle 16 and the adduction / abduction movements of MCP_Bottom knuckle 35, respectively. The motors controlling the flexion / extension movements are fixed to the pulleys with corresponding screws. Motor 1 (20) and motor 1 pulley 21 are fixed together by motor 1 pulley fixing screw 22; motor 2 (31) and motor 2 pulley 32 are fixed together by motor 2 pulley fixing screw 33. Motor 41, which controls the inward / outward movement, is fixed to rod 38 via rod 3 fixing screw 42. The pulleys 21 for motor 1 and 32 for motor 2 employ the same structural design, such as... Figure 6 As shown.

[0062] The parallelogram linkage mechanism is used to realize the adduction / abduction movement of the MCP joint. The links 1 (36) and MCP_Bottom knuckle 35, 2 (37) and MCP_Bottom knuckle 35, 1 (36) and 3 (38), and 2 (37) and 3 (38) are all connected by link fixing nuts 39 and link fixing screws 40 to ensure smooth rotation of the linkage.

[0063] The pretensioning mechanism located within the DIP knuckle 1 of the finger mainly consists of a pretensioning screw 6, a pretensioning pulley 7, a nut insert 8 (No. 1), and a nut insert 9 (No. 2). Nut inserts 8 (No. 1) and 9 (No. 2) are embedded on both sides of the DIP knuckle 1 and are primarily used to secure the pretensioning screw 6, preventing it from shifting or rotating due to stress on the tendon cord 10. The pretensioning pulley 7 is mounted and fixed on the pretensioning screw 6 and rotates synchronously with it. When the tendon cord 10 becomes loose, rotating the pretensioning screw 6 will tighten the tendon cord.

[0064] The power source for the MCP joint comes from motors 2 (31) and 3 (41). Motor 2 (31) provides power for flexion / extension movements via the tendon cord, while motor 3 (41) provides power for adduction / abduction movements via a linkage mechanism. Since the tendon cord 27 is designed to pass through the extension line of the center of the adduction / abduction rotation axis, and since the adduction / abduction movements rely on the rigid structure of the linkage, the two do not interfere with each other. That is, changes in the length of the tendon cord during flexion / extension movements will not cause errors in the adduction / abduction movements, and rotation of the adduction / abduction linkage mechanism will not change the length of the tendon cord 27, thus not affecting the accuracy of the flexion / extension movements. Figure 7 As shown, when the parallelogram linkage rotates clockwise under the drive of motor 41 (i.e., when the MCP joint swings to the left), the length L of tendon 27 between the MCP_Bottom phalanx 35 and the palm 43 remains unchanged, and the lengths of other parts obviously do not change either. The reverse is also true. The decoupling model and principle of the MCP joint are as follows: Figure 8 As shown. Assume point e is the intersection of the center of the MCP joint adduction / abduction rotation axis and chord 2 (27), point e1 is the intersection of chord 2 (27) and the MCP_Bottom phalanx (35), point e2 is on the same straight line as point e1 and also on the same straight line as point e, and point f1 is the position of point e1 after the MCP joint rotates by an angle θ. Establish a rectangular coordinate system xyz with point e as the origin, as shown in the figure. Draw a perpendicular line from point f1 to the y-plane, intersecting the y-plane at point f2. Connect f1f2, ef1, ef2, ee2, e2f1, and e2f2. Then the three lines ee2, e1e2, and e2f2 are perpendicular to each other. The coordinates of point e1 are (a, 0, b), the length of h is bcosθ, and the length of l is bsinθ. Therefore, the coordinates of point f1 are (a, bsinθ, bcosθ). The distance between point e1 and point e is... The distance between point f1 and point e is The two are of equal length, meaning the length of the tendon ligament will not change, and adduction / abduction movements will not affect flexion / extension movements.

[0065] Example 2

[0066] This embodiment provides an anthropomorphic hand based on a hybrid transmission of tendons and links.

[0067] like Figure 9 As shown, a humanoid hand based on a hybrid tendon and link transmission includes the humanoid fingers and palm 43 described in Embodiment 1. The four fingers are mounted in fixed positions on the palm 43, and the thumb 45 is mounted on the palm 43 in a position opposite to the four fingers. The index finger 46, middle finger 47, ring finger 48, and little finger 49 utilize the humanoid fingers described in Embodiment 1, enabling flexion / extension and adduction / abduction movements; the thumb 45, based on Embodiment 1, omits the MCP_Bottom phalanx and can only perform flexion / extension movements. When the humanoid hand grasps an object, the contact between the index finger 46 and the spherical object is as follows... Figure 10 As shown.

[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A humanoid finger based on a hybrid transmission of tendons and links, characterized in that, include: The device includes a drive mechanism, a linkage structure, several tendon cords, a rebound mechanism, and DIP, PIP, MCP, and MCP_Bottom phalanges along the fingertip to palm direction. The DIP and PIP phalanges, the PIP and MCP phalanges, and the MCP and MCP_Bottom phalanges are all connected via the rebound mechanism. The MCP_Bottom phalange is mounted on the palm. One end of the linkage structure is connected to the drive mechanism, and the other end is connected to the MCP_Bottom phalange. Different tendon cords connect to different phalanges and the drive mechanism of the driving phalanges at both ends. The drive mechanism includes a first motor installed in the MCP phalanx, a second motor installed on opposite sides of the palm, and a third motor. The different tendon cords connecting to different phalanges and the drive mechanism for driving these phalanges are specifically as follows: one end of the first tendon cord is connected to the DIP phalanx, and the other end is connected to the first motor; one end of the second tendon cord is connected to the bottom of the MCP phalanx, and the other end is connected to the second motor. The first motor provides power for the flexion / extension movements of the DIP and PIP phalanges, and the second motor provides power for the flexion / extension movements of the MCP phalanx. The linkage structure adopts a parallelogram structure, including a first member, a second member, and a third member connected to the output shaft of the third motor. One end of the first and second members are respectively connected to the third member, and the other end is respectively connected to the MCP_Bottom phalanx. Under the rotation of the third motor, the linkage structure provides power for the adduction / abduction movements of the humanoid hand MCP phalanx. The second tendon cord passes through the extension line of the center of the adduction / abduction movement rotation axis.

2. The anthropomorphic finger based on a hybrid transmission of tendons and links according to claim 1, characterized in that, The DIP knuckle has a pre-reserved mounting position for FSR, which is used for force feedback control of the humanoid finger.

3. The anthropomorphic finger based on a hybrid transmission of tendons and links according to claim 1, characterized in that, The anthropomorphic finger also includes a pre-tensioning mechanism integrated within the DIP knuckle for tensioning loose tendons.

4. The anthropomorphic finger based on a hybrid transmission of tendons and links according to any one of claims 1-3, characterized in that, The rebound mechanism includes a spring that works in conjunction with the tendon cord to complete the flexion / extension movement of the relevant finger joint.

5. A humanoid hand based on a hybrid transmission of tendons and links, comprising a palm, and a thumb, index finger, middle finger, ring finger, and little finger mounted on the palm, characterized in that, The index, middle, ring, and little fingers are all constructed using the humanoid fingers based on a hybrid transmission of tendons and links as described in any one of claims 1-4. The thumb, based on the humanoid fingers, abandons the MCP_Bottom knuckle.

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