Multi-transmission mode integrated arm-hand dexterous hand

Abstract

This invention discloses a multi-transmission integrated dexterous hand. The solution employs a multi-transmission integration approach: the four-finger MCP joint lateral swing uses a motor module-bevel gear system; the thumb PO joint uses a motor module-worm gear system; the wrist joint uses a dual linear electric cylinder-multi-link-orthogonal cross shaft system; and the remaining finger joints use a linear electric cylinder-tendon cable system. This organic integration of multiple transmission methods allows the control system to coordinate various transmission methods upon receiving signals from the robot or host computer, enabling complex hand postures such as grasping, pinching, and finger alignment. Therefore, this dexterous hand possesses high self-sufficiency, high degrees of freedom, compact structure, low inertia, and lightweight flexibility, making it plug-and-play for use with robot bodies.

Description

Technical Field

[0001] This invention belongs to the field of humanoid robot technology, specifically relating to a dexterous hand that integrates multiple transmission methods. Background Technology

[0002] As humanoid robot technology penetrates various scenarios such as industrial manufacturing, medical care, and home services, the performance of dexterous arms, as the core component of end effector, directly determines the robot's ability to interact with the physical world. Current mainstream dexterous arms have achieved breakthroughs in structural integration, motion performance, reliability, and adaptability. For example, Xinuo's Xynova Flex 1 dexterous arm achieves 25 degrees of freedom and a lightweight design of 380g. Zhiyuan Robotics, in its Chinese patent application (publication number CN120056161A), provides a high-degree-of-freedom, small-size, and low-cost four-finger linkage drive and thumb tendon ligament drive scheme for a dexterous hand. Fourier Intelligence, in its Chinese patent application (publication number CN119795222A), provides a dexterous hand and humanoid robot, whose internal "mounting arm" spatial partitioning design and rigid-flexible switchable joint technology provide insights for optimizing wiring interference problems and improving environmental adaptability.

[0003] However, in engineering applications, existing technologies still have many pain points that urgently need to be addressed, specifically in the following aspects: First, pure tendon-driven dexterous hands, with their advantages of lightweight and simple structure, are widely used in multi-joint flexible operation scenarios, but they suffer from drawbacks such as insufficient joint rigidity, easy creep under load, continuous energy consumption for self-sustaining operation, and easy fatigue damage to tendons. Second, pure rigid transmission (such as worm gears, bevel gear sets, etc.) dexterous hands can ensure rigidity and precision, but they suffer from problems such as large end-effector inertia, poor flexibility, and bulky structure. Third, most existing dexterous hand solutions are designed with separate robotic arms and dexterous hands, with dispersed transmission system layouts. The lack of precise matching and collaborative design between the hand and arm easily leads to problems such as motion interference, low space utilization, and poor arm-hand coordination. Summary of the Invention

[0004] To address the inherent drawbacks of purely tendon-based and purely rigid dexterous hand solutions, this invention provides an integrated arm-hand dexterous hand that combines multiple transmission methods, featuring high self-sustain, high degree of freedom, compact structure, low inertia, and lightweight flexibility.

[0005] A multi-transmission integrated arm-hand dexterity hand includes: The hand body consists of the palm and the arm, which are connected at the wrist in a detachable manner; The transmission system is used to transmit multiple degrees of freedom to the wrist joint and finger joints on the hand. The MCP joint (metacarpophalangeal joint) yaw degree of freedom of the four fingers excluding the thumb is transmitted by a drive mechanism based on a motor module-bevel gear set. The PO joint (opposite finger joint) of the thumb is transmitted by a drive mechanism based on a motor module-worm gear. The Pitch and Yaw degrees of freedom of the MCP joint of the thumb are transmitted by a drive mechanism based on chordal differential. The wrist joint is transmitted by a drive mechanism based on a linear electric cylinder-connecting rod-Hooke hinge. The remaining finger joints are transmitted by a drive mechanism based on a linear electric cylinder-chordal. The sensing system uses various types of sensors to collect the rotation angle of each finger joint, the electric cylinder pulling force of each electric cylinder, and the tactile signals of each fingertip, and provides this feedback information to the control system. The control system, based on the above feedback information and integrating multiple transmission control methods, uses a drive motor and electric cylinder to realize complex hand movements including grasping, pinching, and fingering.

[0006] Furthermore, the arm has a wrist joint near the wrist, and each finger of the hand has three joints in sequence from the fingertip to the wrist joint: DIP (distal interphalangeal joint), PIP (proximal interphalangeal joint), and MCP. For the thumb and little finger, there is also a PO joint between the MCP joint and the wrist joint. The DIP joint and PO joint have a single degree of freedom of pitch, and the MCP joint and wrist joint have two degrees of freedom of pitch and yaw.

[0007] Furthermore, the drive mechanism based on the motor module-bevel gear set includes a motor gearbox module, a cross shaft, and two bevel gears. One bevel gear is mounted on the output shaft of the motor gearbox module, and the other bevel gear is mounted on the cross shaft. The finger is mounted on the cross shaft. When the motor gearbox module drives one bevel gear to rotate, it will drive the cross shaft to rotate, thereby realizing the lateral swinging movement of the finger. The components in this drive mechanism are mounted on the palm body through front and rear mounting seats, and the axial angle between the two bevel gears is less than 90 degrees.

[0008] Furthermore, the drive mechanism based on the motor module-worm gear includes a motor gearbox module, a support, a worm, a worm wheel, and a thumb pivot seat. The support is fixedly connected to the palm, the motor gearbox module is fixedly mounted on the support, and a worm is installed at its output end. The worm wheel is arranged inside the support and cooperates with the worm. The thumb pivot seat is fixedly connected to the worm, and a bearing is installed between it, the support, and the palm, allowing it to rotate around the PO joint axis. A stepped pin is installed on the upper part of the thumb pivot seat, and a magnet is installed on the stepped pin. The thumb assembly is assembled on the thumb pivot seat. When the thumb is driven to rotate around the PO joint, the motor gearbox module outputs torque, which drives the thumb assembly to rotate through the worm-worm wheel-thumb pivot seat.

[0009] Furthermore, the drive mechanism based on chord differential motion includes two guide wheels, two chords, two scalpel cylinders, and a rotating outer ring. The two guide wheels are symmetrically arranged on the left and right sides of the thumb pivot seat, and rotate around the pitch axis relative to the thumb pivot seat. The two chords are guided to the rotating outer ring via the two guide wheels and fixed to the symmetrical sides of the back of the rotating outer ring via terminals. The rotating outer ring is mounted on the thumb central pivot and rotates around the yaw axis relative to the central pivot axis. When the two scalpel cylinders installed in the arm cavity simultaneously drive the corresponding chords to tighten at the same speed, the rotating outer ring drives the thumb assembly to rotate around the pitch axis. When the two scalpel cylinders drive the corresponding chords to tighten at a differential speed, the rotating outer ring drives the thumb assembly to rotate around the yaw axis on the thumb central pivot axis.

[0010] Furthermore, the drive mechanism based on linear electric cylinder-connecting rod-Hooke hinge includes a linear electric cylinder, two Hooke hinges, and two-stage connecting rods. The two Hooke hinges are arranged in a cross-shaped orthogonal arrangement in the wrist joint. The first Hooke hinge serves as a pitch axis, with its axis along the left-right direction of the arm, realizing the pitch rotation of the wrist joint. The second Hooke hinge serves as a yaw axis, with its axis along the front-back direction of the arm, realizing the yaw rotation of the wrist joint. The linear electric cylinder is fixed in the arm cavity, and its rod end is connected to the first-stage connecting rod through a fisheye bearing. The first-stage connecting rod is connected to the second-stage connecting rod through a pin, and the end of the second-stage connecting rod is connected to the drive lug of the second Hooke hinge.

[0011] Furthermore, the drive mechanism based on a linear electric cylinder and tendon chords includes a drive disc, a finger fixation component, a cross shaft, two connecting rods, three tendon chords, two small guide wheels, and one large guide wheel. The first connecting rod is mounted on the finger center pivot and rotates around the pitch axis on the MCP joint. The second connecting rod is mounted on the first connecting rod and rotates around the pitch axis on the DIP joint. The drive disc and finger fixation component are mounted on the second connecting rod and rotate around the pitch axis on the PIP joint. The first small guide wheel and the large guide wheel are mounted on the first connecting rod, and the second small guide wheel is mounted on the second connecting rod. On the connecting rod: the first tendon cord is the driving tendon cord, which runs from the center of the cross shaft upwards, passing through the first small guide wheel, the large guide wheel, the second small guide wheel, and the driving disc in sequence, and is then fixed to the rear of the driving disc via a terminal; the second tendon cord runs from the cross shaft, passing through the pitch axis of the MCP joint, and is fixed to the rear of the first connecting rod; the third tendon cord is the passive tendon cord, which is wound in a figure-eight shape around the forefinger fixing member and the first connecting rod, and is fixed by two terminal adjustment blocks located on the side of the first connecting rod. The terminal fixing blocks are fixed to the first connecting rod by screws, and the tension of the third tendon cord can be adjusted by loosening or tightening the screws.

[0012] Furthermore, when it is necessary to drive the DIP and PIP joints to rotate, the corresponding electric cylinders located in the arm cavity tighten the first tendon cable, causing the drive plate and the front fixing component to rotate around the pitch axis on the PIP joint. The tensioned third tendon cable drives the DIP joint to passively rotate around the pitch axis, thereby realizing the flexion movement of the fingers around the DIP and PIP joints. When it is necessary to drive the fingers to rotate around the pitch axis on the MCP joint, the corresponding electric cylinder tightens the second tendon cable, causing the first link and the finger assembly mounted on the first link to rotate.

[0013] Based on the above technical solution, the present invention has the following beneficial technical effects: 1. The present invention integrates a compact hand structure that is closer to or even smaller than the size of a human arm, while also having a high degree of freedom.

[0014] 2. The present invention adopts a configuration that integrates multiple transmission methods, which makes the joint angle, torque and self-holding force superior to existing products. It combines the high self-holding force and joint stiffness of rigid transmission with the compact, low inertia, lightweight and flexible characteristics of tendon and rope transmission.

[0015] 3. This invention integrates the arm and hand, achieving a high degree of integration, and can be used directly with the robot body. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the system composition of the arm-hand integrated dexterous hand that integrates multiple transmission methods according to the present invention.

[0017] Figure 2 This is a schematic diagram of the external structure of the arm-hand integrated dexterous hand of the present invention, which integrates multiple transmission methods. In the figure, (a) corresponds to the main body of the hand, (b) corresponds to the arm, and (c) corresponds to the palm.

[0018] Figure 3 This is a schematic diagram of the hand joints of the arm-hand integrated dexterous hand that integrates multiple transmission methods according to the present invention.

[0019] Figure 4 This is a schematic diagram of a drive structure based on a motor module and a bevel gear set.

[0020] Figure 5 The diagram shows a drive structure based on a motor module and a worm gear. In the diagram, (a) is the position view of the drive structure in the palm of the hand, and (b) is the detailed structure of the drive structure.

[0021] Figure 6 This is a schematic diagram of a drive structure based on tendon-chord differential. In the figure, (a) corresponds to the positional view of the drive structure in the finger, and (b) corresponds to the detailed structure of the drive structure.

[0022] Figure 7This is a schematic diagram of a drive mechanism based on a linear electric cylinder-tendon cable. In the figure, (a) corresponds to the overall assembly view, (b) corresponds to one side view of the motion frame, and (c) corresponds to the other side view of the motion frame. Detailed Implementation

[0023] To describe the present invention in more detail, the technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] To address the inherent drawbacks of purely chordal and purely rigid dexterous hand solutions, this embodiment provides a robotic dexterous hand that integrates multiple transmission methods. The yaw mechanism of the four finger MCP joints employs a motor module-bevel gear system, the PO joint of the thumb uses a motor module-worm gear system, the wrist joint uses a dual linear electric cylinder-multi-link-orthogonal cross shaft system, and the remaining finger joints use a linear electric cylinder-chordal system. This organic integration of multiple transmission methods allows the control system to coordinate various transmission methods upon receiving signals from the robot itself or the host computer, enabling complex hand postures such as grasping, pinching, and finger alignment.

[0025] This implementation adopts an integrated arm-hand design, combining the hand and arm into one unit. The linear electric cylinders driven by the wrist joint and finger tendons can be positioned within the arm, and the control system and power supply module can also be housed within the arm cavity. This fully utilizes space, enabling precise adaptation and integrated coordination between the hand and arm. Figure 1 As shown, the entire dexterous hand adopts a modular design, consisting of five main parts: the main body of the hand, the transmission system, the sensing system, the control system, and the power supply module. Each part works together to achieve dexterous operation functions.

[0026] like Figure 2 As shown, the hand unit, serving as the operational actuator, adopts an integrated arm-hand structure, combining the palm and arm sections. The palm and arm are connected by screws at the wrist, allowing for disassembly and reassembly. The palm section features an anthropomorphic design, including one thumb and four fingers, enabling human-like flexion, extension, adduction, abduction, and finger opposition movements. The hand body is made of high-strength, lightweight materials, with flexible, non-slip pads on the fingertips and palm to adapt to different shaped objects and protect key parts and components of the hand unit. The arm section integrates the wrist joint, base frame, and other structures to house the hardware for the transmission, control, and power supply systems, and provides freedom of movement for the wrist.

[0027] The finger joints in the palm, such as Figure 3As shown, each finger has 2 active degrees of freedom at the MCP joint, 1 active degree of freedom at the DIP joint, and 1 passive degree of freedom at the PIP joint; the thumb and little finger also have 1 active degree of freedom at the PO joint, and the wrist joint WR has 2 active degrees of freedom. Therefore, the entire hand has 19 active degrees of freedom and 5 passive degrees of freedom, for a total of 24 degrees of freedom.

[0028] For different joint movement patterns, the transmission system adopts a corresponding transmission scheme, as follows: (1) The lateral swing of the four-finger metacarpophalangeal joint MCP position adopts the scheme of motor module-bevel gear set.

[0029] Traditional tendon-wire transmission for dexterous hands, using only the four fingers (index, middle, ring, and little fingers), results in limited lateral force output, making it difficult to perform external work. This implementation method uses a direct-drive scheme (bevel gear set), such as... Figure 4 As shown, the lateral movement of the four fingers is achieved through a direct drive mechanism, using a pair of bevel gears to transmit the lateral movement at the base of the fingers. Bevel gear 1 is mounted on the output shaft of the motor gearbox module, and bevel gear 2 is mounted on the cross shaft. The fingers are mounted on the cross shaft. When the motor gearbox module drives bevel gear 1 to rotate, it will drive the cross shaft to rotate, thus achieving the lateral movement of the fingers. An angle sensor can detect the rotation angle of the cross shaft, enabling closed-loop control of the motor gearbox. The entire component is mounted onto the palm body via front and rear mounting brackets. The axial angle between bevel gear 1 and bevel gear 2 is less than 90°, causing the motor gearbox module to tilt from the back of the hand towards the palm, improving the utilization of the internal space of the palm.

[0030] (2) The thumb joint PO adopts a motor module-worm gear scheme.

[0031] Traditional single-tendon rope methods rely on torsion springs for thumb PO joint rotation, resulting in weak reset force and lack of self-holding power. To address this issue, this implementation uses a motor module-worm gear solution, such as... Figure 5 As shown, support one is fixedly connected to the palm, and the motor gearbox module is fixedly installed on support one. A worm gear is installed at the output end of the motor gearbox module, and a worm wheel is arranged inside support one and cooperates with the worm gear. The thumb pivot seat is fixedly connected to the worm gear, and a bearing is installed between it and support one and the palm component, allowing it to rotate around the PO joint axis. A stepped pin is installed on the upper part of the thumb pivot seat, on which a magnet is mounted. The corresponding position of the magnet is support two and the angle sensor on it. The magnet and the angle sensor can rotate relative to each other. The thumb assembly is assembled on the thumb pivot seat. When the thumb needs to be driven to rotate around the PO joint, the motor gearbox module outputs torque, which drives the thumb assembly to rotate through the worm gear-worm wheel-thumb pivot seat. The angle sensor located on support two can provide real-time feedback on the PO rotation angle of the thumb.

[0032] (3) Differential drive scheme of the tendon chords of the thumb MCP joint Pitch and Yaw.

[0033] The thumb's MCP joint needs to possess both pitch and yaw active degrees of freedom, and given its small size and large range of motion, this implementation method employs a chordal differential approach. Figure 6 As shown, guide wheels 1 and 2 are symmetrically arranged on the left and right sides of the thumb pivot seat, and the guide wheels can rotate relative to the thumb pivot seat around the pitch axis. Tendon cords 1 and 2 are guided from the upper part of the guide wheels to the outer ring of the thumb rotation. Tendon cords 1 and 2 are fixed to the symmetrical sides of the back of the outer ring of the thumb rotation using terminals. The outer ring of the thumb rotation is mounted on the central pivot of the thumb and can rotate relative to the central pivot of the thumb around the yaw axis. When the two scalpels on the arm simultaneously drive tendon cords 1 and 2 at the same speed to tighten them, the outer ring of the thumb rotation drives the thumb assembly to rotate around the pitch. A torsion spring can reset the tension when loosening. When the two scalpels drive tendon cords 1 and 2 at a differential speed, the outer ring of the thumb rotation drives the upper thumb assembly to rotate around the yaw axis on the central pivot of the thumb. Angle sensors located on the thumb pivot seat and the central pivot of the thumb provide real-time feedback on the rotation angle of the thumb assembly around the pitch and yaw axes, respectively.

[0034] (4) Wrist dual electric cylinder-multi-link-Hooke hinge scheme.

[0035] The wrist joint requires a large rotation angle, high load-bearing capacity, and tolerance for partial stroke / speed errors of the electric cylinder. Therefore, this embodiment adopts a dual-wrist electric cylinder-multi-link-Hooke hinge scheme. Two Hooke hinges are arranged in a cross orthogonal configuration in the wrist joint. The first Hooke hinge serves as the pitch axis, with its axis along the left-right direction of the arm, realizing the pitch rotation of the wrist joint. The second Hooke hinge serves as the yaw axis, with its axis along the front-back direction of the arm, realizing the yaw rotation of the wrist joint. The wrist electric cylinder is fixed in the arm cavity, and its rod end is connected to the first-stage connecting rod through a fisheye bearing. The first-stage connecting rod is connected to the second-stage connecting rod through a pin, and the end of the second-stage connecting rod is connected to the drive lug of the second Hooke hinge.

[0036] (5) MCP, DIP and PIP tendon ligament drive scheme for four fingers.

[0037] The MCP, DIP, and PIP joints of the four fingers are extremely small, requiring a simultaneous requirement of 1 active degree of freedom and 1 passive degree of freedom. Therefore, this implementation uses a tendon-wire driven scheme. Figure 7 As shown, the L3 link is mounted on the central axis and can rotate around the pitch axis on the MCP joint. The L2 link is mounted on the L3 link and can rotate around the pitch axis on the DIP joint. The drive disc and the forefinition fixation are mounted on the L2 link and can rotate around the pitch axis on the PIP joint.

[0038] Small guide wheel 1 and large guide wheel are mounted on link L3, and small guide wheel 2 is mounted on link L2, both possessing rotational freedom. Tendon cable 1 is the driving tendon cable, starting from the center of the cross shaft and passing sequentially around small guide wheel 1, large guide wheel, and small guide wheel 2, then around the drive disc and fixed to the rear of the drive disc via terminals. Tendon cable 2 is fixed to the rear of link L3 via the pitch axis of the MCP joint before the cross shaft. Tendon cable 3 is the passive tendon cable, wound in a figure-eight shape around the forefinger fixation piece and link L3, and fixed by two terminal adjustment blocks located on the side of link L3. The terminal fixing blocks are fixed to link L3 with screws, and the tension of tendon cable 3 can be adjusted by tightening or loosening the screws to achieve optimal tension.

[0039] When the DIP and PIP joints need to be rotated, the corresponding electric cylinders on the arm tighten the tendon cable 1, causing the drive plate and the front fixing component to rotate around the pitch axis of the PIP. The tensioned tendon cable 3 then passively rotates the DIP joint around the pitch axis, thus achieving the flexion movement of the finger around the DIP and PIP. When the finger needs to be rotated around the pitch axis of the MCP, the corresponding electric cylinder tightens the tendon cable 2, causing the L3 connecting rod and the finger assembly mounted on it to rotate. Each joint can be reset by a torsion spring, and the rotation angle can be fed back in real time by an angle sensor.

[0040] For different joint working conditions, corresponding transmission methods can be adopted. In this example, multiple transmission methods are integrated, which combines the advantages of tendon and cable transmission, such as flexibility, low inertia, and saving hand volume, with rigid transmission, strong self-sustaining force, and high rigidity.

[0041] The sensing system is used to detect the state of the dexterous hand in real time, providing accurate data for the control system. This embodiment incorporates multiple sensors of various types: angle sensors at each joint provide real-time feedback on the joint rotation angle; force sensors at the bottom of the electric cylinder provide real-time feedback on the cylinder's tension; and tactile sensors at the fingertips provide real-time feedback on the contact between the hand and the object. By integrating these multiple types of sensors, a complete dexterous hand sensing system can be established, providing accurate data for the control system's decisions and enabling precise and meticulous operation.

[0042] Combining the features of the overall layout, multi-transmission integration, and multi-sensor integration described above, the integrated arm-hand layout in this embodiment is as follows: the entire dexterous hand is divided into an arm and a palm, which are connected by screws at the wrist interface. The interface has a built-in tendon guide channel and an electrical integration slot; power components such as linear electric cylinders are centrally integrated inside the integrated forearm frame, avoiding external pipelines and protruding parts; the wrist joint component is embedded between the integrated forearm frame and the palm frame; the arm and palm can be connected as one unit or disassembled, facilitating assembly and maintenance.

[0043] Arm layout: The core load-bearing component is an integrally printed aluminum alloy matrix frame, which also serves as a heat dissipation device. The drive component (linear electric cylinder) of the tendon cable transmission is arranged in a ring on the outside of the matrix frame. The two wrist electric cylinders and the multi-link assembly required for the wrist joint are arranged inside the frame. The electrical unit is arranged in the inner cavity of the frame, below the wrist electric cylinder. The bottom of the wrist electric cylinder and the finger electric cylinder are integrated with built-in tension sensors to monitor the tension of the electric cylinder.

[0044] Hand layout: The index, middle, and ring fingers have lateral swing components, while the little finger and thumb PO components are located at the base of the fingers. The motor module is arranged inside the palm, making full use of the palm space. The finger components above the aforementioned lateral swing components and PO components can rotate with these motion components. The little finger lateral swing component is located within the flip joint block of the little finger PO component and rotates with the joint to avoid motion interference. The MCP, DIP, and PIP components of the four fingers are mounted on the four-finger lateral swing components, providing freedom of rotation around their respective joint pitches. The thumb DIP and PIP components are mounted on the thumb MCP component, providing freedom of rotation around the thumb's respective joint pitches. Angle position sensors are located next to the corresponding rotation joints, and tactile sensors are located at the fingertips. All of these electrical components are integrated into the fingers.

[0045] With the above design, this embodiment maintains an arm with a diameter ≤80mm, a wrist joint distance ≤200mm from the base, a hand length ≤180mm (from wrist to the tip of the middle finger), a hand width ≤80mm (four fingers together), and a hand thickness ≤45mm; the finger diameter does not exceed 20mm. These dimensions are close to or smaller than a human arm, while possessing 19 active degrees of freedom and 5 passive degrees of freedom, making it the smallest high-degree-of-freedom dexterous hand currently available.

[0046] This embodiment, employing a multi-transmission integrated scheme, significantly outperforms existing products in terms of rotation angle and torque: wrist pitch ±55°, lateral swing ±40°; four-finger flexion 0~90°, single-finger lateral swing ±20°, thumb flexion 0~70°, thumb rotation 0~40°; finger lateral swing speed reaches 15rpm, torque reaches 0.4Nm; thumb PO joint speed reaches 31.3rpm, torque reaches 0.6Nm, and the entire hand can bear a weight ≥30kg.

[0047] The dexterous hand in this example achieves a high degree of integration of the hand body, transmission system, sensing system, control system and power supply module, which can supply the robot body with plug and play.

[0048] The above description of the embodiments is provided to enable those skilled in the art to understand and apply the present invention. Those skilled in the art can readily make various modifications to the above embodiments and apply the general principles described herein to other embodiments without creative effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made to the present invention by those skilled in the art based on the disclosure thereof should be within the scope of protection of the present invention.

Claims

1. A multi-transmission integrated arm-hand dexterity hand, characterized in that, include: The hand body consists of the palm and the arm, which are connected at the wrist in a detachable manner; The transmission system is used to transmit multiple degrees of freedom to the wrist joint and finger joints on the palm. The MCP joint yaw degree of freedom of the four fingers except the thumb is transmitted by a drive mechanism based on a motor module-bevel gear set. The PO joint of the thumb is transmitted by a drive mechanism based on a motor module-worm gear. The MCP joint pitch and yaw degree of freedom of the thumb are transmitted by a drive mechanism based on chordal differential. The wrist joint is transmitted by a drive mechanism based on a linear electric cylinder-connecting rod-Hooke joint. The remaining finger joints are transmitted by a drive mechanism based on a linear electric cylinder-chordal. The sensing system uses various types of sensors to collect the rotation angle of each finger joint, the electric cylinder pulling force of each electric cylinder, and the tactile signals of each fingertip, and provides this feedback information to the control system. The control system, based on the above feedback information and integrating multiple transmission control methods, uses a drive motor and electric cylinder to realize complex hand movements including grasping, pinching, and fingering.

2. The multi-transmission integrated arm-hand dexterous hand according to claim 1, characterized in that: The arm has a wrist joint near the wrist, and each finger of the hand has three joints, DIP, PIP, and MCP, arranged sequentially from the fingertip to the wrist joint; for the thumb and little finger, there is also a PO joint between the MCP joint and the wrist joint, wherein the DIP joint and PO joint have a single degree of freedom of pitch, and the MCP joint and wrist joint have two degrees of freedom of pitch and yaw.

3. The multi-transmission integrated arm-hand dexterous hand according to claim 1, characterized in that: The drive mechanism based on the motor module-bevel gear set includes a motor gearbox module, a cross shaft, and two bevel gears. One bevel gear is mounted on the output shaft of the motor gearbox module, and the other bevel gear is mounted on the cross shaft. The finger is mounted on the cross shaft. When the motor gearbox module drives one bevel gear to rotate, it will drive the cross shaft to rotate, thereby realizing the lateral movement of the finger. The components in this drive mechanism are mounted on the palm body through front and rear mounting seats, and the axial angle between the two bevel gears is less than 90 degrees.

4. The multi-transmission integrated arm-hand dexterous hand according to claim 1, characterized in that: The drive mechanism based on a motor module and worm gear includes a motor gearbox module, a support, a worm, a worm wheel, and a thumb pivot seat. The support is fixedly connected to the palm, the motor gearbox module is fixedly mounted on the support, and a worm is installed at its output end. The worm wheel is arranged inside the support and cooperates with the worm. The thumb pivot seat is fixedly connected to the worm, and a bearing is installed between it, the support, and the palm, allowing it to rotate around the PO joint axis. A stepped pin is installed on the upper part of the thumb pivot seat, and a magnet is installed on the stepped pin. The thumb assembly is assembled on the thumb pivot seat. When the thumb is driven to rotate around the PO joint, the motor gearbox module outputs torque, which drives the thumb assembly to rotate through the worm, worm wheel, and thumb pivot seat.

5. The multi-transmission integrated arm-hand dexterous hand according to claim 1, characterized in that: The drive mechanism based on chord differential motion includes two guide wheels, two chords, two scalpel cylinders, and a rotating outer ring. The two guide wheels are symmetrically arranged on the left and right sides of the thumb pivot seat and rotate around the pitch axis relative to the thumb pivot seat. The two chords are guided to the rotating outer ring via the two guide wheels and fixed to the symmetrical sides of the back of the rotating outer ring via terminals. The rotating outer ring is mounted on the thumb central pivot and rotates around the yaw axis relative to the central pivot axis. When the two scalpel cylinders installed in the arm cavity simultaneously drive the corresponding chords to tighten at the same speed, the rotating outer ring drives the thumb assembly to rotate around the pitch axis. When the two scalpel cylinders drive the corresponding chords to tighten at a differential speed, the rotating outer ring drives the thumb assembly to rotate around the yaw axis on the thumb central pivot axis.

6. The multi-transmission integrated arm-hand dexterous hand according to claim 1, characterized in that: The drive mechanism based on a linear electric cylinder-connecting rod-Hooke hinge includes a linear electric cylinder, two Hooke hinges, and two-stage connecting rods. The two Hooke hinges are arranged in a cross-shaped orthogonal configuration within the wrist joint. The first Hooke hinge serves as a pitch axis, with its axis along the left-right direction of the arm, enabling pitch rotation of the wrist joint. The second Hooke hinge serves as a yaw axis, with its axis along the front-back direction of the arm, enabling yaw rotation of the wrist joint. The linear electric cylinder is fixed within the arm cavity, and its extension rod end is connected to the first-stage connecting rod via a fisheye bearing. The first-stage connecting rod is connected to the second-stage connecting rod via a pin, and the end of the second-stage connecting rod is connected to the drive lug of the second Hooke hinge.

7. The multi-transmission integrated arm-hand dexterous hand according to claim 1, characterized in that: The linear electric cylinder-tendon cable drive mechanism includes a drive disc, a finger fixation component, a cross shaft, two connecting rods, three tendon cables, two small guide wheels, and one large guide wheel. The first connecting rod is mounted on the finger center pivot and rotates around the pitch axis on the MCP joint. The second connecting rod is mounted on the first connecting rod and rotates around the pitch axis on the DIP joint. The drive disc and finger fixation component are mounted on the second connecting rod and rotate around the pitch axis on the PIP joint. The first small guide wheel and the large guide wheel are mounted on the first connecting rod, and the second small guide wheel is mounted on the second connecting rod. The first tendon cord is a driving tendon cord, which runs from the center of the cross shaft upwards, passing through the first small guide wheel, the large guide wheel, the second small guide wheel, and the driving disc in sequence, and is then fixed to the rear of the driving disc via a terminal; the second tendon cord runs from the cross shaft, passing through the pitch axis of the MCP joint, and is fixed to the rear of the first connecting rod; the third tendon cord is a passive tendon cord, which is wound in a figure-eight shape around the forefinger fixation member and the first connecting rod, and is fixed by two terminal adjustment blocks located on the side of the first connecting rod. The terminal fixing blocks are fixed to the first connecting rod by screws, and the tension of the third tendon cord can be adjusted by loosening or tightening the screws.

8. The multi-transmission integrated arm-hand dexterous hand according to claim 7, characterized in that: When it is necessary to drive the DIP and PIP joints to rotate, the corresponding electric cylinders located in the arm cavity tighten the first tendon cable, causing the drive plate and the front fixing component to rotate around the pitch axis on the PIP joint. The tensioned third tendon cable drives the DIP joint to passively rotate around the pitch axis, thereby realizing the flexion movement of the fingers around the DIP and PIP joints. When it is necessary to drive the fingers to rotate around the pitch axis on the MCP joint, the corresponding electric cylinder tightens the second tendon cable, causing the first link and the finger assembly mounted on the first link to rotate.

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