Tendon-driven robotic arm structure and robot

Abstract

A tendon-driven robotic arm structure and robot include a shoulder connecting plate, a shoulder support end frame, an upper arm support frame, a forearm support frame, and an end effector. The first end of the shoulder support end frame is rotatably mounted on one side of the shoulder connecting plate, and a shoulder drive wheel is also provided at the first end of the shoulder support end frame. A shoulder joint drive module C is provided on the other side of the shoulder connecting plate, and the shoulder joint drive module C is connected to the shoulder drive wheel through a tendon transmission component. This invention achieves double the peak torque under the same driving kinetic energy conditions, or enables the use of lower power drives under the same output torque conditions, resulting in lower manufacturing costs, less overall space occupied, less additional load weight, and lower energy consumption during operation. It achieves a balance between lightweight design and high load-bearing capacity.

Description

Technical Field

[0001] This invention belongs to the technical field of robotics, specifically relating to a tendon-driven robotic arm structure and a robot. Background Technology

[0002] Robots, especially humanoid robots that connect high-tech industrial chains such as artificial intelligence, advanced manufacturing, and new materials, are the most dazzling jewels in the crown of manufacturing. As a crucial carrier for robot work, the structure of the robot arm has evolved into a multi-configuration technology system. Its technological iterations revolve around performance optimization and scenario adaptation, making it difficult to achieve both lightweight design and high load-bearing capacity simultaneously. Typically, in industrial settings, the main design direction sacrifices lightweight design for higher power and torque joint motors to increase load-bearing capacity. This inevitably leads to high manufacturing costs, large space requirements, and excessive energy waste due to excessive load, resulting in higher overall operating costs. In intelligent operation and interaction scenarios, primarily for humanoid robots, the focus is on lightweight design at the expense of load-bearing capacity or arm degrees of freedom. The advantages are reduced robot weight, increased safety during human interaction, and more aesthetically pleasing design. The disadvantage is the inability to perform high-load or highly complex tasks.

[0003] In the prior art, patent document CN119388478A describes an industrial-grade high-load humanoid robot arm, a dual-arm system, and a humanoid robot, belonging to the field of robot technology. It includes a first drive joint, a second drive joint, a third drive joint, a fourth drive joint, a fifth drive joint, a sixth drive joint, and a seventh drive joint. The mounting components include a first mounting component, a second mounting component, a third mounting component, a fourth mounting component, a fifth mounting component, and a sixth mounting component, as well as a six-dimensional force sensor and an end effector. The joints and mounting components are separated and connected sequentially. This solution uses direct motor drive and has no special configuration. Its industrial-grade load capacity refers to achieving a seven-degree-of-freedom humanoid configuration to avoid insufficient applicability in various scenarios. Therefore, it can be inferred that to achieve a high load capacity, the joints must be made large and heavy, failing to solve the problem of balancing lightweight design and high load-bearing capacity.

[0004] Similarly, patent document CN119388478A describes a lightweight robotic arm structure, including a shoulder rotation module, a shoulder extension module, an upper arm rotation module, an elbow extension module, a forearm rotation module, a wrist rotation extension module, and a grasping module, all made of aluminum alloy. The shoulder rotation module is connected to the upper arm rotation module via the shoulder extension module. One end of the upper arm rotation module is connected to the forearm rotation module via the elbow extension module, and the other end of the forearm rotation module is connected to the wrist rotation extension module, which is connected to the grasping module. Each of the shoulder rotation module, shoulder extension module, upper arm rotation module, elbow extension module, and forearm rotation module contains a servo drive component. The wrist rotation extension module includes two stacked servos. This solution still uses direct motor drive; its lightweight design is reflected in the aluminum alloy joint modules and the use of two stacked servos in the wrist rotation extension module. However, aluminum alloy, as a relatively lightweight conventional material, is also frequently used in robots. Its shortcomings, such as poor strength and rigidity, need to be improved in materials science. While servo motors are lighter than joint modules, their load-bearing capacity is also much lower. Although using servo motors in wrist joints can meet the general requirements of humanoid robots, it still cannot meet the working conditions of heavy loads and has not solved the problem of balancing lightweight design with high load-bearing capacity. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes a tendon-driven robotic arm structure that achieves double the peak torque under the same driving kinetic energy conditions through dual-drive control and opposite dual-power output at multiple joints, or enables the use of lower power drives under the same output torque conditions. This results in lower manufacturing costs, less overall space and additional load weight, and lower energy consumption during operation, achieving both lightweight design and high load-bearing capacity.

[0006] The specific technical solution is as follows:

[0007] A tendon-driven robotic arm structure includes a shoulder connecting plate, a shoulder support end frame, an upper arm support frame, a forearm support frame, and an end effector. The first end of the shoulder support end frame is rotatably mounted on one side of the shoulder connecting plate, and a shoulder drive wheel is also provided at the first end of the shoulder support end frame. A shoulder joint drive module C is provided on the other side of the shoulder connecting plate, and the shoulder joint drive module C is connected to the shoulder drive wheel through a tendon transmission component.

[0008] Shoulder joint drive module A and shoulder joint drive module B are embedded in the shoulder support end frame. The output ends of shoulder joint drive module A and shoulder joint drive module B are respectively located on opposite sides of the shoulder support end frame. The shoulder connecting plate and the shoulder support end frame are rotatably connected through a shoulder opposite-direction double-output bevel gear assembly. Shoulder joint drive module A and shoulder joint drive module B are respectively connected to the two input ends of the shoulder opposite-direction double-output bevel gear assembly through tendon transmission components.

[0009] The upper arm support frame is embedded with elbow joint drive module A and elbow joint drive module B. The output ends of elbow joint drive module A and elbow joint drive module B are respectively located on opposite sides of the upper arm support frame. The upper arm support frame and the forearm support frame are rotatably connected by an elbow-oriented dual-output bevel gear assembly. Elbow joint drive module A and elbow joint drive module B are respectively connected to the two input ends of the elbow-oriented dual-output bevel gear assembly through a tendon transmission component.

[0010] The forearm support frame is embedded with a wrist joint drive module A and a wrist joint drive module B. The output ends of the wrist joint drive module A and the wrist joint drive module B are respectively located on opposite sides of the forearm support frame. The forearm support frame and the end effector are rotatably connected through a wrist-mounted opposite-direction dual-output coupling wheel assembly. The wrist joint drive module A and the wrist joint drive module B are respectively connected to the two input ends of the wrist-mounted opposite-direction dual-output coupling wheel assembly through a tendon transmission component.

[0011] Furthermore, the shoulder-mounted opposite-direction dual-output bevel gear assembly includes a first driving bevel gear, a second driving bevel gear, and a driven bevel gear. The first driving bevel gear and the second driving bevel gear have the same rotation axis, and the first driving bevel gear and the second driving bevel gear mesh with the two sides of the driven bevel gear respectively. A synchronous output shaft is connected to the center of the driven bevel gear, and the end of the synchronous output shaft is fixedly connected to the boom support frame.

[0012] The shoulder support end frame has two shoulder support lug structures. The center parts of the first drive bevel gear and the second drive bevel gear are respectively mounted on the two shoulder support lug structures via rotating shafts. The rotating shaft is also equipped with a drive force input wheel. A shoulder joint rotation kit is rotatably sleeved on the synchronous output shaft. The shoulder joint rotation kit is rotatably connected to the shoulder support lug structure, and its rotation center is the same as that of the second drive bevel gear.

[0013] Furthermore, the tendon transmission component is a belt drive structure, chain drive structure, gear drive structure, or tendon wire drive structure and its combination, and the shoulder joint drive module A, shoulder joint drive module B, shoulder joint drive module C, elbow joint drive module A, elbow joint drive module B, wrist joint drive module A and wrist joint drive module B are all joint motor modules.

[0014] Furthermore, the shoulder support end frame is provided with two opposing drive mounting holes. The diameter of the drive mounting holes is larger than the outer diameter of the shoulder joint drive module A and the shoulder joint drive module B, so that the shoulder joint drive module A and the shoulder joint drive module B have tension adjustment space.

[0015] Adjustable mounting plates are provided on both sides of the shoulder support end frame, and the adjustable mounting plates are located at the opening of the drive mounting hole. The shoulder joint drive module A and the shoulder joint drive module B are fixedly mounted on the adjustable mounting plates. The adjustable mounting plates are provided with a set of strip holes. A set of screw holes is also provided on the side of the shoulder support end frame 2. The screw hole set is positioned corresponding to the set of strip holes. Pre-tightening screws are provided in the set of strip holes. The pre-tightening screws pass through the set of strip holes and cooperate with the set of screw holes. A tensioning support frame is also provided on the shoulder support end frame. The tensioning support frame is provided with a push rod assembly or a pull rod assembly.

[0016] Furthermore, the shoulder joint rotation kit consists of a support connecting housing and two auxiliary support ear housings. The two auxiliary support ear housings are symmetrically arranged on both sides of the support connecting housing. The two auxiliary support ear housings are rotatably connected to the shoulder support ear structure through angular contact bearings. Bearing mounting grooves are provided on both the upper and lower sides of the support connecting housing, and bearings are installed in the bearing mounting grooves. The outer wall of the middle part of the synchronous output shaft and the inner wall of the bearing mounting groove are respectively interference-fitted with the inner and outer rings of the bearing.

[0017] Furthermore, the synchronous output shaft includes at least a first-stage limiting rod, a second-stage mounting rod, and a third-stage fastening threaded rod. The first-stage limiting rod, the second-stage mounting rod, and the third-stage fastening threaded rod are arranged in a stepped manner, with the first-stage limiting rod having the largest outer diameter and the third-stage fastening threaded rod having the smallest outer diameter. A fastening bolt structure is fitted on the third-stage fastening threaded rod, and the fastening bolt structure presses the support connecting housing tightly against the side wall of the first-stage limiting rod. The second-stage mounting rod is used to install the driven bevel gear.

[0018] Furthermore, the wrist-mounted opposite-direction dual-output coupling wheel assembly includes a cross-axis connector, a first joint pivot, a second joint pivot, and an end connector. The first and second joint pivots are staggered on different opposite sides of the cross-axis connector. The forearm support frame has two wrist joint lugs at its end. The cross-axis connector is rotatably connected to the two wrist joint lugs via the first joint pivot. A first idler wheel and a second idler wheel are respectively provided at both ends of the first joint pivot. A third idler wheel and a fixed wheel are respectively provided at both ends of the second joint pivot. The end connector is connected to the cross-axis connector via the second joint pivot. The end connector is used to mount the end effector hand, and the fixed wheel is fixedly connected to the end connector. Wrist joint drive module A and wrist joint drive module B are respectively driven by the first and second idler wheels. The two sides of the first idler wheel are synchronously driven by the third idler wheel and one side of the fixed wheel. The two sides of the second idler wheel are synchronously driven by the third idler wheel and the other side of the fixed wheel.

[0019] Furthermore, the first idler wheel, the second idler wheel, the third idler wheel, and the fixed wheel are each provided with at least one tendon rope groove, and a transmission tendon rope structure is sleeved between the first idler wheel, the second idler wheel, the third idler wheel, and the fixed wheel.

[0020] Furthermore, the transmission tendon rope structure is a steel rope sling, which is set in the tendon rope groove of the first idler wheel. Then, the two ends of the transmission steel rope sling pass through the tendon rope grooves of the third idler wheel and the fixed wheel respectively. Finally, the transmission steel rope sling is set in the tendon rope groove of the second idler wheel to form a transmission loop structure.

[0021] Furthermore, the steel rope sling is tensioned and wound in the first idler pulley, second idler pulley, third idler pulley and the fixed wheel to achieve the transmission setting.

[0022] A robot is also provided, characterized by employing at least one tendon-driven robotic arm structure.

[0023] The beneficial effects of this invention are as follows: by using dual drive control to output dual power in opposite directions at multiple joints, double the peak torque can be achieved under the same driving kinetic energy conditions, or a lower power drive can be used under the same output torque conditions, resulting in lower manufacturing costs, less overall space occupied and less additional load weight, and thus lower energy consumption during operation, achieving both lightweight design and high load-bearing capacity. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0025] Figure 2 This is a schematic diagram of the installation of the shoulder support end frame and the shoulder opposite-direction double output bevel gear assembly in this invention.

[0026] Figure 3 This is a three-dimensional structural diagram of the shoulder-mounted opposite-direction dual-output bevel gear assembly in this invention.

[0027] Figure 4 This is a side view of the shoulder-mounted opposite-direction dual-output bevel gear assembly in this invention.

[0028] Figure 5 This is a schematic diagram of the installation of the boom support frame and the elbow-mounted opposite-direction dual-output bevel gear assembly in this invention.

[0029] Figure 6 This is a schematic diagram of the installation of the forearm support frame and the wrist-mounted opposite-direction dual-output coupling wheel assembly in this invention.

[0030] Figure 7 This is a partial structural schematic diagram of the wrist-mounted opposite-direction dual-output coupling wheel assembly in this invention.

[0031] Explanation of reference numerals in the attached drawings: 1. Shoulder connecting plate; 2. Shoulder support frame; 3. Upper arm support frame; 4. Forearm support frame; 5. End effector hand; 6. Shoulder opposite-direction dual-output bevel gear assembly; 7. Elbow opposite-direction dual-output bevel gear assembly; 8. Wrist opposite-direction dual-output coupling wheel assembly;

[0032] Shoulder joint drive module A21; shoulder joint drive module B22; shoulder joint drive module C23; shoulder support structure 24; drive force input wheel 25; shoulder drive wheel 26;

[0033] Elbow joint drive module A31; Elbow joint drive module B32; Wrist joint drive module A41; Wrist joint drive module B42;

[0034] First drive bevel gear 61; Second drive bevel gear 62; Driven bevel gear 63; Synchronous output shaft 64; Shoulder joint rotation assembly 65;

[0035] Cross-axis connector 81; first joint pivot 82; second joint pivot 83; end connector 84; wrist joint support ear 85; first idler wheel 86; second idler wheel 87; third idler wheel 88; fixed wheel 89. Detailed Implementation

[0036] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0037] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element 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 invention.

[0038] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can be a direct connection or a connection through an intermediate medium; or they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] Example:

[0040] like Figures 1 to 7 As shown: A tendon-driven robotic arm structure includes a shoulder connecting plate 1, a shoulder support end frame 2, an upper arm support frame 3, a forearm support frame 4, and an end effector 5. The first end of the shoulder support end frame 2 is rotatably mounted on one side of the shoulder connecting plate 1, and a shoulder drive wheel 26 is also provided at the first end of the shoulder support end frame 2. A shoulder joint drive module C23 is provided on the other side of the shoulder connecting plate 1. The shoulder joint drive module C23 is connected to the shoulder drive wheel 26 through a tendon transmission component. The shoulder joint drive module C23 controls the rotation of the shoulder drive wheel 26, so that the shoulder support end frame 2 rotates relative to the shoulder connecting plate 1. The shoulder connecting plate 1 is fixedly mounted on the robot body with a flange-like structure around it. Therefore, the shoulder joint drive module C23 can be concealed in the robot body. The output torque can be increased by using a higher power drive motor or a larger reduction gear ratio without being limited by space. The rotation of the shoulder support end frame 2 relative to the robot body is the first rotational degree of freedom, which is equivalent to the back-and-forth swinging of a human shoulder.

[0041] Shoulder joint drive module A21 and shoulder joint drive module B22 are embedded in the shoulder support end frame 2. The output ends of shoulder joint drive module A21 and shoulder joint drive module B22 are respectively located on opposite sides of shoulder support end frame 2. Shoulder connecting plate 1 and shoulder support end frame 2 are rotatably connected by shoulder opposite-direction double-output bevel gear assembly 6. Shoulder joint drive module A21 and shoulder joint drive module B22 are respectively connected to the two input ends of shoulder opposite-direction double-output bevel gear assembly 6 through tendon transmission components, thereby realizing opposite-direction double-output shoulder joint dual-degree-of-freedom movement.

[0042] The upper arm support frame 3 is embedded with an elbow joint drive module A31 and an elbow joint drive module B32. The output ends of the elbow joint drive module A31 and the elbow joint drive module B32 are respectively located on opposite sides of the upper arm support frame 3. The upper arm support frame 3 and the forearm support frame 4 are rotatably connected by an elbow-oriented dual-output bevel gear assembly 7. The elbow joint drive module A31 and the elbow joint drive module B32 are respectively connected to the two input ends of the elbow-oriented dual-output bevel gear assembly 7 through tendon transmission components, thereby realizing the elbow joint dual-degree-of-freedom motion with opposite-direction dual output. The elbow joint and the shoulder joint both require bending and rotation for opposite-direction dual output. The dual-degree-of-freedom motion mode is the same, and the same control structure can be used.

[0043] The forearm support frame 4 is embedded with a wrist joint drive module A41 and a wrist joint drive module B42. The output ends of the wrist joint drive module A41 and the wrist joint drive module B42 are respectively located on opposite sides of the forearm support frame 4. The forearm support frame 4 and the end effector hand 5 are rotatably connected through the wrist opposite-direction dual-output coupling wheel assembly 8. The wrist joint drive module A41 and the wrist joint drive module B42 are respectively connected to the two input ends of the wrist opposite-direction dual-output coupling wheel assembly 8 through tendon transmission components, thereby realizing the opposite-direction dual-output dual-degree-of-freedom movement of the wrist joint. The wrist joint requires different dual-degree-of-freedom movement modes than the elbow joint and the shoulder joint. The wrist joint requires bending and twisting in different directions, such as left and right and forward and backward, so different coupling design structures are required.

[0044] The aforementioned tendon transmission components include belt drive structures, chain drive structures, gear drive structures, or tendon wire drive structures and their combinations. Shoulder joint drive modules A21, B22, C23, A31, B32, A41, and B42 are all joint motor modules. Furthermore, the output ends of shoulder joint drive modules A21, B22, C23, A31, B32, A41, and B42 can also adopt other transmission structures in other application scenarios. However, other transmission structures occupy a large space and have a large mass, making them less suitable for robots.

[0045] The aforementioned shoulder-mounted counter-rotating dual-output bevel gear assembly 6 includes a first driving bevel gear 61, a second driving bevel gear 62, and a driven bevel gear 63. The rotation axes of the first driving bevel gear 61 and the second driving bevel gear 62 are the same, i.e., on a straight line. The first driving bevel gear 61 and the second driving bevel gear 62 respectively mesh with the two sides of the driven bevel gear 63, meaning that the first driving bevel gear 61 and the second driving bevel gear 62 are symmetrically arranged. The first driving bevel gear 61, the second driving bevel gear 62, and the driven bevel gear 63 are all helical bevel gears. Helical bevel gears provide smoother transmission, stronger load-bearing capacity, and lower operating noise. A synchronous output shaft 64 is connected to the center of the driven bevel gear 63, and the end of the synchronous output shaft 64 is fixedly connected to the boom support frame 3.

[0046] Two drive mounting holes are provided on both sides of the middle of the shoulder support end frame 2. Shoulder joint drive module A21 and shoulder joint drive module B22 are respectively installed in the two drive mounting holes. A fixed mounting plate and an adjusting mounting plate are provided at the opening of each drive mounting hole. The fixed mounting plate is fixedly connected to the shoulder support end frame 2 and can be integrated into one unit. Shoulder joint drive module A21 or shoulder joint drive module B22 is installed on one side of the adjusting mounting plate. A through hole is provided in the middle of both the fixed mounting plate and the adjusting mounting plate, through which the output end of shoulder joint drive module A21 or shoulder joint drive module B22 passes. That is, the housing of shoulder joint drive module A21 or shoulder joint drive module B22 near the output end is fixedly mounted on the adjusting mounting plate by screws, etc. The output end of shoulder joint drive module A21 or shoulder joint drive module B22 passing through the through hole facilitates connection with the first drive bevel gear 61 and the second drive... A bevel gear 62 enables transmission. The other side of the adjusting mounting plate has threaded holes, and the corresponding fixed mounting plate has slotted holes. Pre-tightening bolts pass through the slotted holes and engage with the threaded holes to pre-tighten the adjusting mounting plate onto the fixed mounting plate. A tensioning support frame is also provided on the shoulder support end frame. This tensioning support frame has push rod or pull rod assemblies, which can be composed of bolt structures and one or two threaded hole structures. The shoulder joint drive module A21 or shoulder joint drive module B22, which is connected to the adjusting mounting plate, is embedded in the fixed mounting plate via the pre-tightening bolts, equivalent to being mounted on the shoulder support end frame 2. The main body of the rotary drive device is placed in the drive mounting hole, and then the push rod or pull rod assembly pushes and pulls the synchronous belt drive structure, chain drive structure, or tendon rope drive structure of the tendon transmission component to achieve tension. Finally, the pre-tightening bolts are tightened.

[0047] Two shoulder support lug structures 24 are located at the end of the shoulder support frame 2. The central parts of the first drive bevel gear 61 and the second drive bevel gear 62 are respectively mounted on the two shoulder support lug structures 24 via rotating shafts. The rotating shafts and the shoulder support lug structures 24 can be rotatably mounted via bearing structures. A drive force input wheel 25 is also provided on the rotating shaft, which is a driven wheel. A drive wheel is provided at the output end of the shoulder joint drive module A21 and the shoulder joint drive module B22, respectively. The two drive wheels are respectively connected to the two drive force input wheels 25 via tendon transmission components. The drive wheel and the driven wheel 67 are synchronous pulleys, sprockets, or traction rope pulleys. A shoulder joint rotation kit 65 is also rotatably sleeved on the synchronous output shaft 64. The shoulder joint rotation kit 65 is rotatably connected to the shoulder support lug structure 24, and its rotation center is the same as that of the second drive bevel gear 62.

[0048] The shoulder joint rotation assembly 65 consists of a support connecting housing and two auxiliary support ear housings. The two auxiliary support ear housings are symmetrically arranged on both sides of the support connecting housing. The two auxiliary support ear housings are rotatably connected to the shoulder support ear structure 24 through angular contact bearings to form two coaxial transverse rotation pairs. Bearing mounting grooves are provided on both the upper and lower sides of the support connecting housing, and bearings are installed in the bearing mounting grooves. The outer wall of the middle part of the synchronous output shaft 64 and the inner wall of the bearing mounting groove are respectively interference-fitted with the inner and outer rings of the bearing to form a vertical rotation pair.

[0049] The aforementioned synchronous output shaft 64 includes a first-stage limiting rod, a second-stage mounting rod, and a third-stage fastening threaded rod. It may also include more stepped shaft sections of varying thicknesses, but a three-stage shaft meets basic usage requirements. The first-stage limiting rod, second-stage mounting rod, and third-stage fastening threaded rod are arranged in a stepped manner, with the first-stage limiting rod having the largest outer diameter and the third-stage fastening threaded rod having the smallest. A fastening bolt structure is fitted onto the third-stage fastening threaded rod, which presses the supporting connecting housing tightly against the side wall of the first-stage limiting rod. The second-stage mounting rod is used to install the driven bevel gear 63. Thus, both ends of the synchronous output shaft are rotatably connected via bearings, and the axial and radial positioning and fixation are achieved through the fastening bolt structure in cooperation with the first-stage limiting rod, making the installation structure more stable.

[0050] The second-stage mounting rod has a multi-prism structure, and can also be an irregular shape such as an ellipse or a large semicircle, as long as it is not cylindrical. However, the multi-prism structure is easier to install and provides more uniform load distribution. It is generally a square prism or a hexagonal prism, and a multi-prism mounting hole is opened at the rotation axis of the driven bevel gear 63. The second-stage mounting rod mates with the multi-prism mounting hole. A through hole is also opened at the axis of the stepped mounting shaft to facilitate the passage of the control line.

[0051] In summary, the shoulder connecting plate 1 and the shoulder support end frame 2 are rotatably connected by the shoulder opposite-direction dual-output bevel gear assembly 6, thereby realizing opposite-direction dual-output degrees of freedom (corresponding to the outward extension of the upper arm movement and the upper arm torsional movement respectively, and the combined control can obtain multiplied power) in the following specific principle:

[0052] Given that the rotation direction of the bevel gear sections of the first driving bevel gear 61, the second driving bevel gear 62, and the driven bevel gear 63 is clockwise or counterclockwise relative to each other, then:

[0053] When only the lateral rotation joint rotates: When the shoulder joint drive module A21 and the shoulder joint drive module B22 control the first drive bevel gear 61 and the second drive bevel gear 62 to rotate in the same direction and at the same speed around the rotation center, that is, when the bevel gear parts of the first drive bevel gear 61 and the second drive bevel gear 62 rotate clockwise and the other counterclockwise, the driving forces on both sides of the driven bevel gear 63 completely conflict, so it cannot rotate. Thus, the driven bevel gear 63, the first drive bevel gear 61 and the second drive bevel gear 62 and their connecting parts temporarily form a whole. The rotational force of the first drive bevel gear 61 and the second drive bevel gear 62 around its rotation center in the same direction and at the same speed will drive this whole to rotate around the rotation center, that is, the lateral rotation joint rotates. This achieves the effect that the output power of the two rotary drive devices serves as the force for the shoulder joint to expand outward or contract inward. The robot arm connected to the synchronous output shaft 64 can obtain double the rotational torque, thereby achieving a higher peak torque, providing more sufficient kinetic energy, and allowing the use of a smaller power rotary drive device, resulting in lower manufacturing costs and a smaller overall space and weight.

[0054] Only the vertical rotating joint rotates: When the shoulder joint drive module A21 and the shoulder joint drive module B22 control the first drive bevel gear 61 and the second drive bevel gear 62 to rotate in opposite directions at the same speed around the rotation center, that is, when the bevel gear parts opposite to the first drive bevel gear 61 and the second drive bevel gear 62 rotate clockwise or counterclockwise, the driven bevel gear 63 is subjected to driving forces on both sides, and the superposition of the two driving forces causes the driven bevel gear 63 to rotate in one direction, that is, the vertical rotating joint rotates. Figure 2For example, when the bevel gear sections of the first driving bevel gear 61 and the second driving bevel gear 62 both rotate clockwise, the first driving bevel gear 61 pushes the left meshing surface of the driven bevel gear 63 outward, causing the driven bevel gear 63 to rotate counterclockwise; while the second driving bevel gear 62 pushes the right meshing surface of the driven bevel gear 63 inward, similarly causing the driven bevel gear 63 to rotate counterclockwise. However, when viewed from the first driving bevel gear 61 towards the second driving bevel gear 62, their rotation directions around the same rotation center are different, and vice versa. Therefore, the output power of both rotary drive devices serves as the torsional power of the shoulder joint, allowing the robot arm connected to the synchronous output shaft 64 to obtain double the rotational torque, thus achieving a higher peak torque, providing more sufficient kinetic energy, and allowing the use of a smaller rotary drive device, resulting in lower manufacturing costs and a smaller overall space and weight.

[0055] The vertical and lateral revolute joints rotate in combination: When the shoulder joint drive module A21 and shoulder joint drive module B22 control the first drive bevel gear 61 and the second drive bevel gear 62 to rotate around the rotation center in the same or opposite directions with a speed difference, if they rotate in the same direction with a speed difference, the differential speed rotation stroke of the drive bevel gear with the higher speed is used to drive the vertical revolute joint, while the remaining same-speed rotation strokes of the two gears in the same direction are used to drive the lateral revolute joint. If they rotate in opposite directions with a speed difference, the differential speed rotation stroke of the drive bevel gear with the higher speed is used to drive the lateral revolute joint, while the remaining same-speed rotation strokes of the two gears in opposite directions are used to drive the vertical revolute joint. Therefore, by controlling the opposite-direction dual power output at the shoulder joint through dual drive, the overall energy consumption of the movement process is lower, while the kinetic energy of the required revolute joint rotation can be controlled to be stronger.

[0056] The aforementioned wrist-mounted opposite-direction dual-output coupling wheel assembly 8 includes a cross-axis connector 81, a first joint pivot 82, a second joint pivot 83, and an end connector 84. The first joint pivot 82 and the second joint pivot 83 are alternately arranged on different opposite sides of the cross-axis connector 81, and their rotation axes are perpendicular to each other. Specifically, the first joint pivot 82 is installed on two opposite sides of the cross-axis connector 81, i.e., the left and right sides, and the second joint pivot 83 is installed on the other side of the cross-axis connector 81. On the two opposite outer sides, namely the front and rear sides, there is a height difference between the first joint pivot 82 and the second joint pivot 83, that is, the rotation axes of the first joint pivot 82 and the second joint pivot 83 are not on the same plane. If they were on the same plane, it would be possible, but it would easily lead to insufficient rotation space and jamming. Just like when the second joint pivot 83 is installed on the upper and lower sides of the cross shaft connector 81, it would also lead to insufficient rotation space and jamming. It is not completely unusable and can be used when the rotation range requirement is small, but it is generally not used.

[0057] The forearm support frame 4 has two wrist joint lugs 85 at its end. A cross-axis connector 81 is rotatably connected to the two wrist joint lugs 85 via a first joint pivot 82. A first idler wheel 86 and a second idler wheel 87 are respectively provided at both ends of the first joint pivot 82, and the rotation axes of the first joint pivot 82, the first idler wheel 86, and the second idler wheel 87 coincide. A third idler wheel 88 and a fixed wheel 89 are respectively provided at both ends of the second joint pivot 83, and the rotation axes of the second joint pivot 83, the third idler wheel 88, and the fixed wheel 89 coincide. The third idler wheel 88 is rotatably connected to one end of the second joint pivot 83, and the fixed wheel 89 is fixedly connected to the other end of the second joint pivot 83. The end connector 84 is fixedly connected to the cross-axis connector 81 via the second joint pivot 83. Therefore, the fixed wheel 89, the end connector 84, the second joint pivot 83, and the cross-axis connector 81 form a [structure / system]. For the overall motion, the end effector 84 is used to install the end effector hand 5, which can be a bionic hand, a five-finger dexterous hand, a three-finger gripper, or a two-finger gripper. The fixed wheel 89 is fixedly connected to the end effector 84. The wrist joint drive module A41 and the wrist joint drive module B42 are respectively connected to the first idler wheel and the second idler wheel. The two sides of the first idler wheel 86 are synchronously connected to the third idler wheel 88 and one side of the fixed wheel 89. The two sides of the second idler wheel 87 are synchronously connected to the third idler wheel 88 and the other side of the fixed wheel 89. The specific synchronous transmission connection method is as follows: tendon grooves are provided on the first idler wheel 86, the second idler wheel 87, the third idler wheel 88 and the fixed wheel 89, and a transmission tendon rope structure is sleeved between the tendon rope grooves of the first idler wheel 86, the second idler wheel 87, the third idler wheel 88 and the fixed wheel 89. Other flexible transmission methods such as chain transmission can also be implemented to achieve synchronous transmission connection.

[0058] The transmission tendon rope structure is a steel rope sling, which is located in the tendon rope groove of the first idler wheel 86. Then, the two ends of the transmission steel rope sling pass through the tendon rope grooves of the third idler wheel 88 and the fixed wheel 89, respectively. Finally, the transmission steel rope sling is located in the tendon rope groove of the second idler wheel 87, forming a transmission loop structure. The wrist joint drive module A41 and the first idler wheel, as well as the wrist joint drive module B42 and the second idler wheel, can be connected by chain drive or tendon rope drive separately, or they can be combined by connecting the steel rope sling in the tendon rope grooves of the first idler wheel 86, the third idler wheel 88, the fixed wheel 89, and the second idler wheel 87 for combined transmission. Specifically, the transmission tendon rope structure consists of two chain sections and two steel rope sections. Both ends of the two chain sections are connected to the two steel rope sections respectively, forming a loop connection structure of chain sections, steel rope sections, chain sections, and steel rope sections. The two chain sections are connected to the output ends of the wrist joint drive module A41 and the wrist joint drive module B42 respectively. Similarly, the two steel rope sections are fitted between the tendon rope grooves of the first idler wheel 86, the third idler wheel 88, the fixed wheel 89, and the second idler wheel 87.

[0059] Furthermore, the steel cable sling is installed in the tendon grooves of the first idler pulley 86, the second idler pulley 87, the third idler pulley 88, and the fixed wheel 89 using either a tensioned sleeve or a winding method to achieve the transmission. Sleeving refers to wrapping the cable around the tendon groove about half a turn, which has the advantage of requiring less material and being lighter overall. Winding refers to wrapping the cable around the tendon groove at least once, which has the advantage of more stable transmission and less slippage. Sleeving is generally used, and the slippage problem is solved using fastening holes and fastening clips. Specifically, two fastening holes are provided on the side of the fixed wheel 89, and fastening clips are provided at both ends of the steel cable sling. The fastening clips are fitted into the fastening holes to prevent the steel cable sling from slipping in the tendon groove, thus forming a transmission loop structure in the tendon grooves of the first idler pulley 86, the second idler pulley 87, the third idler pulley 88, and the fixed wheel 89.

[0060] The aforementioned transmission steel rope sling connects the first idler pulley 86, the second idler pulley 87, the third idler pulley 88, and the fixed wheel 89 into a relatively integrated whole. When the wrist joint drive module A41 and the wrist joint drive module B42 drive the first idler pulley 86 and the second idler pulley 87 to rotate in the same direction and at the same speed, the tendon transmission component pulls the third idler pulley 88 and the fixed wheel 89 together as a relatively integrated whole to rotate around the first joint pivot 82. Because the fixed wheel 89 is fixedly connected to the end connector 84, the end connector 84 will also rotate around the first joint pivot 82. 82 completes the rotation in the X-axis direction through dual drive control. The dual drive control rotation provides higher peak torque and more sufficient kinetic energy. The free rotation of the third idler wheel 88 can adjust the relative positional changes of the tendon transmission components caused by the change in rotation space. During the rotation around the first joint shaft 82, the fixed wheel 89 moves closer to the second idler wheel 87, and the distance between the tendon transmission components becomes shorter. At the same time, the third idler wheel 88 moves away from the first idler wheel 86, and the distance between the tendon transmission components becomes longer. The overall length remains unchanged and needs to be adjusted by rotating the third idler wheel 88.

[0061] When wrist joint drive module A41 and wrist joint drive module B42 drive the first idler wheel 86 and the second idler wheel 87 to rotate in opposite directions at the same speed, taking the first idler wheel 86 pulling the fixed wheel 89 closer to it via the tendon transmission component as an example, at this time, the whole assembly consisting of the fixed wheel 89 and the end connector 84 rotates around the second joint pivot 83. Because the tendon transmission component is a flexible transmission structure, the driving force driven by wrist joint drive module B42 cannot be directly applied to the fixed wheel 89 by pushing in the opposite direction. Therefore, the driving force transmitted to the second idler wheel 87 is then... The rotation of the third idler wheel 88 is transmitted to the first idler wheel 86, which manifests as a superimposed driving force. Therefore, the third idler wheel 88 not only needs to adjust the relative positional changes of the tendon transmission components caused by the change in rotation space, but also can transmit kinetic energy so that the kinetic energy of the wrist joint drive module A41 and the wrist joint drive module B42 can be superimposed to form the torque of the end connector 84 rotating around the first joint pivot 82 or the second joint pivot 83, thereby achieving a higher peak torque, providing more sufficient kinetic energy, and achieving the technical effects of lower energy consumption, lower manufacturing cost, and lower overall space and weight in the overall motion process.

[0062] When wrist joint drive module A41 and wrist joint drive module B42 drive the first idler wheel 86 and the second idler wheel 87 to rotate in the same or opposite directions at different speeds, the end connector 84 performs a compound motion around the first joint pivot 82 and the second joint pivot 83. The principle is the same as the individual motions mentioned above, and their motion speed relationship can be described as follows:

[0063] If the driving force of the wrist joint drive module A41 and the wrist joint drive module B42 is transmitted to the first idler wheel 86 and the second idler wheel 87, their rotational speeds are respectively and The positive and negative signs represent clockwise and counterclockwise directions, respectively. The calculation methods for their rotational speeds around the first joint pivot 82 and the second joint pivot 83 are as follows:

[0064] The end connector 84 rotates around the first joint pivot 82 at a speed of When the first idler wheel 86 and the second idler wheel 87 rotate in opposite directions and at the same speed, ,thereby That is, the end connector 84 rotates only around the second joint pivot 83;

[0065] The end connector 84 rotates around the second joint pivot 83 at a speed of When the first idler wheel 86 and the second idler wheel 87 rotate in the same direction and at the same speed, ,thereby That is, the end connector 84 rotates only around the first joint pivot 82.

[0066] Its end connector 84 performs a compound motion around the first joint pivot 82 and the second joint pivot 83. The corresponding rotation speed can be calculated using the above formula, and the amount of rotation amplitude can be obtained based on the time.

[0067] The present invention also provides a robot employing at least one tendon-driven robotic arm structure.

[0068] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims.

Claims

1. A tendon-driven robotic arm structure, characterized in that: It includes a shoulder connecting plate, a shoulder support end frame, an upper arm support frame, a forearm support frame, and an end effector. The first end of the shoulder support end frame is rotatably mounted on one side of the shoulder connecting plate, and a shoulder drive wheel is also provided at the first end of the shoulder support end frame. A shoulder joint drive module C is provided on the other side of the shoulder connecting plate. The shoulder joint drive module C is connected to the shoulder drive wheel through a tendon transmission component. Shoulder joint drive module A and shoulder joint drive module B are embedded in the shoulder support end frame. The output ends of shoulder joint drive module A and shoulder joint drive module B are respectively located on opposite sides of the shoulder support end frame. The shoulder connecting plate and the shoulder support end frame are rotatably connected through a shoulder opposite-direction double-output bevel gear assembly. Shoulder joint drive module A and shoulder joint drive module B are respectively connected to the two input ends of the shoulder opposite-direction double-output bevel gear assembly through tendon transmission components. The upper arm support frame is embedded with elbow joint drive module A and elbow joint drive module B. The output ends of elbow joint drive module A and elbow joint drive module B are respectively located on opposite sides of the upper arm support frame. The upper arm support frame and the forearm support frame are rotatably connected by an elbow-oriented dual-output bevel gear assembly. Elbow joint drive module A and elbow joint drive module B are respectively connected to the two input ends of the elbow-oriented dual-output bevel gear assembly through a tendon transmission component. The forearm support frame is embedded with a wrist joint drive module A and a wrist joint drive module B. The output ends of the wrist joint drive module A and the wrist joint drive module B are respectively located on opposite sides of the forearm support frame. The forearm support frame and the end effector are rotatably connected through a wrist-mounted opposite-direction dual-output coupling wheel assembly. The wrist joint drive module A and the wrist joint drive module B are respectively connected to the two input ends of the wrist-mounted opposite-direction dual-output coupling wheel assembly through a tendon transmission component.

2. The tendon-driven robotic arm structure according to claim 1, characterized in that: The shoulder-mounted opposite-direction dual-output bevel gear assembly includes a first driving bevel gear, a second driving bevel gear, and a driven bevel gear. The first driving bevel gear and the second driving bevel gear have the same rotation axis, and the first driving bevel gear and the second driving bevel gear mesh with the two sides of the driven bevel gear respectively. A synchronous output shaft is connected to the center of the driven bevel gear, and the end of the synchronous output shaft is fixedly connected to the boom support frame. The shoulder support end frame has two shoulder support lug structures. The center parts of the first drive bevel gear and the second drive bevel gear are respectively mounted on the two shoulder support lug structures via rotating shafts. The rotating shaft is also equipped with a drive force input wheel. A shoulder joint rotation kit is rotatably sleeved on the synchronous output shaft. The shoulder joint rotation kit is rotatably connected to the shoulder support lug structure, and its rotation center is the same as that of the second drive bevel gear.

3. The tendon-driven robotic arm structure according to claim 2, characterized in that: The tendon transmission component is a belt drive structure, chain drive structure, gear drive structure or tendon wire drive structure and its combination, and the shoulder joint drive module A, shoulder joint drive module B, shoulder joint drive module C, elbow joint drive module A, elbow joint drive module B, wrist joint drive module A and wrist joint drive module B are all joint motor modules.

4. The tendon-driven robotic arm structure according to claim 2 or 3, characterized in that: The shoulder support end frame is provided with two opposing drive mounting holes. The diameter of the drive mounting holes is larger than the outer diameter of the shoulder joint drive module A and the shoulder joint drive module B, so that the shoulder joint drive module A and the shoulder joint drive module B have tension adjustment space. Adjustable mounting plates are provided on both sides of the shoulder support end frame, and the adjustable mounting plates are located at the opening of the drive mounting hole. The shoulder joint drive module A and the shoulder joint drive module B are fixedly mounted on the adjustable mounting plates. The adjustable mounting plates are provided with a set of strip holes. A set of screw holes is also provided on the side of the shoulder support end frame 2. The screw hole set is positioned corresponding to the set of strip holes. Pre-tightening screws are provided in the set of strip holes. The pre-tightening screws pass through the set of strip holes and cooperate with the set of screw holes. A tensioning support frame is also provided on the shoulder support end frame. The tensioning support frame is provided with a push rod assembly or a pull rod assembly.

5. The tendon-driven robotic arm structure according to claim 4, characterized in that: The shoulder joint rotation kit consists of a support connecting housing and two auxiliary support ear housings. The two auxiliary support ear housings are symmetrically arranged on both sides of the support connecting housing. The two auxiliary support ear housings are rotatably connected to the shoulder support ear structure through angular contact bearings. Bearing mounting grooves are provided on both the upper and lower sides of the support connecting housing, and bearings are installed in the bearing mounting grooves. The outer wall of the middle part of the synchronous output shaft and the inner wall of the bearing mounting groove are respectively interference-fitted with the inner and outer rings of the bearing.

6. The tendon-driven robotic arm structure according to claim 5, characterized in that: The synchronous output shaft includes at least a first-stage limiting rod, a second-stage mounting rod, and a third-stage fastening threaded rod. The first-stage limiting rod, the second-stage mounting rod, and the third-stage fastening threaded rod are arranged in a stepped manner, with the first-stage limiting rod having the largest outer diameter and the third-stage fastening threaded rod having the smallest outer diameter. A fastening bolt structure is fitted on the third-stage fastening threaded rod, and the fastening bolt structure presses the support connecting housing tightly against the side wall of the first-stage limiting rod. The second-stage mounting rod is used to install the driven bevel gear.

7. The tendon-driven robotic arm structure according to any one of claims 1-3, 5 or 6, characterized in that: The wrist-mounted opposite-direction dual-output coupling wheel assembly includes a cross-axis connector, a first joint pivot, a second joint pivot, and an end connector. The first and second joint pivots are staggered on different opposite sides of the cross-axis connector. The end of the forearm support frame has two wrist joint lugs. The cross-axis connector is rotatably connected to the two wrist joint lugs via the first joint pivot. The first and second idler wheels are respectively provided at both ends of the first joint pivot. The second and third idler wheels are respectively provided at both ends of the second joint pivot. The end connector is connected to the cross-axis connector via the second joint pivot. The end connector is used to install the end effector hand, and the fixed wheel is fixedly connected to the end connector. Wrist joint drive module A and wrist joint drive module B are respectively driven by the first and second idler wheels. The two sides of the first idler wheel are synchronously driven by the third idler wheel and one side of the fixed wheel. The two sides of the second idler wheel are synchronously driven by the other side of the third idler wheel and the fixed wheel.

8. The tendon-driven robotic arm structure according to claim 7, characterized in that: The first idler wheel, the second idler wheel, the third idler wheel, and the fixed wheel are each provided with at least one tendon rope groove, and a transmission tendon rope structure is sleeved between the first idler wheel, the second idler wheel, the third idler wheel, and the fixed wheel.

9. The tendon-driven robotic arm structure according to claim 8, characterized in that: The transmission tendon rope structure is a steel rope sling. The steel rope sling is set in the tendon rope groove of the first idler wheel. Then, the two ends of the transmission steel rope sling pass through the tendon rope grooves of the third idler wheel and the fixed wheel respectively. Finally, the transmission steel rope sling is set in the tendon rope groove of the second idler wheel to form a transmission loop structure. Furthermore, the steel rope sling is tensioned and wound in the first idler pulley, second idler pulley, third idler pulley and the fixed wheel to achieve the transmission setting.

10. A robot, characterized in that, A robotic arm structure driven by at least one tendon is used.

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