Driving rear-mounted bionic rope-driven upper limb robot

Abstract

The application discloses a driving rear-mounted bionic rope-driven upper limb mechanical arm, which comprises a rack, a driving module, a rope-driven composite shoulder joint, an upper arm component, an ulna, a radius component and a wrist joint. The wrist joint is provided with a wrist sun gear, an output planetary gear, a wrist planet carrier and a wrist central shaft. The wrist planet carrier is rotationally connected with the wrist central shaft, the wrist central shaft is rotationally connected with the wrist sun gear, the output planetary gear is rotationally connected with the wrist planet carrier, and the wrist sun gear and the output planetary gear are differentially connected. The driving module outputs a rope connected through forward and reverse winding, which drives the upper arm component to drive the ulna to complete elbow flexion and extension movement, drives the radius component to rotate, drives the output planetary gear to rotate around the wrist sun gear, and drives the wrist planet carrier to rotate around the axis of the wrist central shaft. The application can match the skeleton-joint biological structure and movement mechanism of human body, and improves the rigidity and load characteristics of the mechanism.

Description

Technical Field

[0001] This invention relates to the field of robot joint technology, and more specifically to a bionic rope-driven upper limb robotic arm with a rear-mounted drive. Background Technology

[0002] The skeleton of the upper limb below the shoulder is mainly composed of the humerus of the upper arm, the ulna and radius of the forearm, and the lunate and scaphoid bones of the hand. Joints, through lubricated hinge-like biological structures such as articular surfaces, joint capsules, and joint cavities, along with ligaments and muscles, work together to constrain the skeleton. Examples include the humeral-ulnar joint, humeroradial joint, and proximal radioulnar joint formed by the humerus, ulna, and radius in the upper arm; and the distal radioulnar joint, radiocarpal joint, and midcarpal joint near the hand. Driven in a specific direction at a single joint, it is often achieved by a group of muscles. For instance, the biceps brachii and triceps brachii act as agonist and antagonist muscles, respectively, with the two muscles tightening and lengthening to achieve elbow flexion and extension. This antagonistic working characteristic of muscles makes human movement more stable and provides a certain degree of protection for the bones and joints.

[0003] Existing robots differ from the human skeleton-muscle-tendon drive system. Serial robots have high motor loads at joints, resulting in poor dynamic characteristics, and the hierarchical serial structure leads to cumulative errors. Parallel robots have rear-mounted motors, but the coupling effect of multiple kinematic chains limits their range of motion. In terms of drive equipment, linear drive components with good motion / force transmission characteristics, such as electric cylinders and hydraulic cylinders, have limited drive strokes, further affecting the end-effector workspace, and have large inertia. In contrast, rope-driven systems offer superior long-range power transmission, lightweight design, and reverse drive characteristics, making it easier to achieve force gain effects, thus meeting the requirements of lightweight, compliant, and safe humanoid robots. Summary of the Invention

[0004] To overcome the defects and shortcomings of existing technologies, this invention provides a biomimetic rope-driven upper limb robotic arm with a rear-mounted drive. In order to fabricate a humanoid biomimetic robot upper limb with small space occupancy and large workspace, as well as high energy density and load characteristics, this invention utilizes the rigid-flexible separation of human skeleton and muscle and the antagonistic driving characteristics of muscles, introduces a composite mechanical hinge as a biomimetic joint, and combines advanced spatial mechanics with rope drive technology to make the remote power transmission, force gain, and reverse drive characteristics of the rope on the robotic arm compatible with the high rigidity and load characteristics of the spatial mechanism, thereby improving the overall performance of the humanoid robot.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention provides a rear-drive bionic cable-driven upper limb robotic arm, comprising: a frame, a drive module, a cable-driven composite shoulder joint, an upper arm component, an ulna, a radius component, and a wrist joint;

[0007] The drive module and the cable-driven composite shoulder joint are connected to the frame. The drive module is connected to the cable-driven composite shoulder joint. The cable-driven composite shoulder joint is connected to the upper arm component. The upper arm component is movably connected to the ulna and radius component. The ulna and radius component is connected to the wrist joint.

[0008] The wrist joint is equipped with a wrist sun gear, an output planet gear, a wrist planet carrier, and a wrist central shaft. The wrist planet carrier is rotatably connected to the wrist central shaft, the wrist central shaft is rotatably connected to the wrist sun gear, the output planet gear is rotatably connected to the wrist planet carrier, and the wrist sun gear and the output planet gear are differentially connected.

[0009] The drive module outputs ropes that are wound in both directions, driving the upper arm component to move the ulna to complete elbow flexion and extension movements, driving the radius component to rotate, driving the wrist sun gear to drive the output planetary gear to rotate, and driving the wrist sun gear to drive the wrist planetary carrier to rotate around the axis of the wrist center axis.

[0010] As a preferred technical solution, the upper arm component includes an upper arm side plate, a transmission rod, a drive rod, and a rocker arm;

[0011] The upper arm lateral plate has the humeroulnar joint rotation center, the first hinge point, and the fifth hinge point.

[0012] One end of the rocker is connected to the fifth hinge point. The rocker body is equipped with a slide rail, and a slider is provided on the slide rail to form a sliding pair.

[0013] The end of the ulna is connected to the rotation center of the humeroulnar joint, and the extended part of the end of the ulna is movably connected to one end of the transmission rod to form a third hinge point;

[0014] The middle part of the drive rod is connected to the first hinge point, and the two ends of the drive rod are connected to the other end of the transmission rod and the slider, respectively, forming the second hinge point and the fourth hinge point;

[0015] The drive module drives the slider to slide on the slide rail via a rope, which in turn drives the drive rod to rotate, and the corresponding ulna is lifted to complete the elbow flexion movement.

[0016] The drive module drives the drive rod to rotate in the opposite direction via a rope, and the corresponding ulna is lowered to complete the elbow extension movement.

[0017] As a preferred technical solution, the slider is provided with a second guide wheel center, and the second guide wheel center is provided with a pulley;

[0018] The end of the joystick is provided with a first elbow joint cable drive terminal, the first elbow joint cable drive terminal is provided with a third guide wheel center, and the third guide wheel center is provided with a pulley;

[0019] Relative to the first hinge point, the drive rod is provided with a first guide wheel center symmetrical to the fourth hinge point, and the first guide wheel center is provided with a pulley;

[0020] The upper arm side plate is provided with a second elbow joint cable drive terminal. Relative to the first hinge point, the second elbow joint cable drive terminal is provided with a fourth guide wheel center symmetrical to the fifth hinge point. The fourth guide wheel center is provided with a pulley.

[0021] The first elbow joint cable drive terminal receives the cable connected to the drive module winding, passes through the center of the third guide wheel and the center of the second guide wheel, and is finally fixed at the end of the first elbow joint cable drive terminal. When the cable of the first elbow joint cable drive terminal is retracted, the length of the line connecting the center of the second guide wheel and the center of the third guide wheel decreases, which drives the drive rod to rotate, and the corresponding ulna is lifted to complete the elbow flexion movement.

[0022] The second elbow joint cable drive terminal receives a cable connected to the same drive module in the opposite direction. The cable passes through the center of the fourth guide wheel and the center of the first guide wheel, and is finally fixed at the end of the second elbow joint cable drive terminal. When the cable passing through the second elbow joint cable drive terminal is retracted, the length of the line connecting the center of the first guide wheel and the center of the fourth guide wheel decreases, causing the drive rod to rotate in the opposite direction. The corresponding ulna is lowered to complete the elbow extension movement.

[0023] As a preferred technical solution, the radius component includes: a radius connecting rod, a first radius ball joint seat, a gear ring, a first radius drive wheel, a second radius drive wheel, a second radius ball joint seat, a humeroradial joint drive gear, and a third radius drive wheel;

[0024] The radial link is connected to the upper arm component, the radial link is rotatably connected to the first radial ball joint seat, and the first radial ball joint seat is rotatably connected to the second radial ball joint seat and the humeroradial joint drive gear.

[0025] The third radial drive wheel is fixedly connected to the humeroradial joint drive gear, which meshes with a gear ring. The gear ring is fixedly connected to the first radial drive wheel, and the radial connecting rod is fixedly connected to the second radial drive wheel. The first radial drive wheel is connected to the second radial drive wheel via a rope.

[0026] The first and second radial ball joints form a ball joint, which restricts the movement between the upper arm components and the radial link.

[0027] The drive module drives the third radial drive wheel to rotate, the third radial drive wheel drives the humeroradial joint drive gear to rotate, the humeroradial joint drive gear drives the gear ring to rotate, the gear ring drives the first radial drive wheel to rotate, the first radial drive wheel drives the second radial drive wheel to rotate, and the second radial drive wheel drives the radial connecting rod to rotate.

[0028] As a preferred technical solution, the upper arm component is also provided with a humeroradial joint connector, and the radial link is also provided with a humeral connecting shaft;

[0029] The humeral connecting shaft is rotatably connected to the second radial ball joint, and the humeral connecting shaft is fixedly connected to the humeroradial joint connector of the upper arm component.

[0030] As a preferred technical solution, the second radial ball joint is provided with two third elbow joint cable drive interfaces and a fourth radial drive wheel, which receive two cables from the same drive module and are connected by a winding. The cables pass around the two fourth radial drive wheels located on the second radial ball joint in opposite directions and are finally fixed on the third radial drive wheel, driving the humeroradial joint drive gear to rotate.

[0031] As a preferred technical solution, a guide wheel is provided on the first radial ball joint seat, and two rope windings in opposite directions are connected to the first radial drive wheel. After passing through the guide wheel, they are wound in opposite directions on the second radial drive wheel. The first radial drive wheel drives the second radial drive wheel to rotate, and the second radial drive wheel drives the radial connecting rod to rotate.

[0032] As a preferred technical solution, the wrist joint includes: a first wrist sun wheel and a second wrist sun wheel;

[0033] The wrist central axis is fixedly connected to the radius component, the wrist central axis is connected to the ulnar ball joint, the wrist central axis is rotatably connected to the first wrist sun gear and the second wrist sun gear, and the output planetary gear is rotatably connected to the wrist planetary carrier.

[0034] The first arm sun gear, the second arm sun gear, and the output planet form a differential transmission relationship;

[0035] The first arm sun gear has two oppositely oriented rope windings, which are wrapped around and fixed to the output planet gear;

[0036] The second arm sun gear has two oppositely oriented rope windings, which are wrapped around and fixed to the output planet gear;

[0037] The two sides of the wrist planetary carrier are respectively provided with wrist guide wheels. The rope windings of the first wrist sun gear and the second wrist sun gear are transmitted through the corresponding wrist guide wheels and then wrapped and fixed on the output planetary gear.

[0038] As a preferred technical solution, the wrist central shaft is provided with a keyway and is also connected to a first side wire guide device and a second side wire guide device respectively;

[0039] The first side cable guide device is provided with a first guide wheel frame, the first guide wheel frame is provided with a first wrist transmission wheel, and the first side cable guide device is connected to a first wrist rope drive interface.

[0040] The first wrist rope drive interface receives two ropes connected to the drive module winding, which are then wrapped around the first wrist sun gear in opposite directions after passing through the first wrist transmission wheel;

[0041] The second side cable guide device is equipped with a second guide wheel frame, and the second guide wheel frame is equipped with a second wrist drive wheel. The second side cable guide device is connected to a second wrist rope drive interface.

[0042] The second wrist cable drive interface receives two cables connected to the drive module winding, which, after passing through the second wrist transmission wheel, are wrapped around the second wrist sun wheel in opposite directions.

[0043] As a preferred technical solution, a stiffness adjustment device is provided and fixedly connected between the first wrist rope drive interface and the first side cable guide device, and a stiffness adjustment device is provided and fixedly connected between the second wrist rope drive interface and the second side cable guide device, so as to realize the adjustable rope tension at the far end.

[0044] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0045] (1) The present invention transmits power remotely through ropes, which improves dynamic characteristics and safety and compliance for human interaction. All the remote driving ropes are in pairs, realizing antagonistic driving characteristics and having a certain normal driving capability, making it easier for humans and machines to cooperate.

[0046] (2) The present invention constructs a spatial four-bar linkage by means of the upper arm component, ulna, radius component and wrist joint, and constructs multiple planar four-bar linkages in the upper arm component, which to a certain extent conforms to the human skeletal-joint biological structure and movement mechanism, and improves the rigidity and load characteristics of the mechanism.

[0047] (3) Since the rope sleeve is directly connected to the local joint of the robot arm, the present invention constructs a passive compliant component structure, which makes the joint stiffness and end-effector accuracy threshold dynamically adjustable, reduces the difficulty of rope assembly, extends the service life of the rope, and is conducive to the long-term stable operation of the rope-driven robot arm. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the overall structure of the bionic rope-driven upper limb robotic arm with a rear-mounted drive according to the present invention.

[0049] Figure 2 This is a schematic diagram of the mechanism below the shoulder joint of the rope-driven robotic arm of the present invention;

[0050] Figure 3 This is a schematic diagram of the upper arm component of the present invention;

[0051] Figure 4 This is a diagram showing the rotation center of the components of the upper arm structure of the present invention;

[0052] Figure 5 This is a schematic diagram of the distal structure of the radial component relative to the upper arm component of the present invention;

[0053] Figure 6 This is a schematic diagram of the wrist joint structure of the present invention;

[0054] Figure 7 This is an anatomical diagram of the wrist joint of the present invention;

[0055] Figure 8 This is a schematic diagram of the wire passing device on the first side of the wrist joint of the present invention;

[0056] Figure 9 This is a schematic diagram of the wire passing device on the second side of the wrist joint in the present invention;

[0057] Figure 10 This is a schematic diagram of the proximal structure of the radial component relative to the upper arm component of the present invention;

[0058] Figure 11 This is a schematic diagram of the pronation / supination axis of the radial component of the present invention.

[0059] Figure 12 This is a schematic diagram of the movement of the ulna and radius components relative to the upper arm flexion in this invention;

[0060] Figure 13 This is a schematic diagram illustrating the pronation / supination of the radial component relative to the ulna in this invention.

[0061] Among them, 1-frame, 2-drive module, 3-rope-driven composite shoulder joint, 4-upper arm component, 5-ulna, 6-radius component, 7-wrist joint, 8-rope sleeve;

[0062] 401-First upper arm side plate, 402-Second upper arm side plate, 403-Rock bar, 404-Drive rod, 405-Transmission rod, 406-Slider, 407-First elbow joint cable drive terminal, 408-Second elbow joint cable drive terminal, 409-Upper arm connecting plate, 410-Radiohumeral joint connector, 411-Anti-corresponding cable guide wheel, 4011-Humeral joint rotation center, 4012-First hinge point, 4013-Fifth hinge point, 4041-Fourth hinge point, 4042-First guide wheel center, 4051-Second hinge point, 4052-Third hinge point, 4061-Second guide wheel center, 4071-Third guide wheel center, 4081-Fourth guide wheel center;

[0063] 601-Radial connecting rod, 602-First radial ball joint seat, 603-Gear ring, 604-First radial drive wheel, 605-Second radial drive wheel, 606-Second radial ball joint seat, 607-Humeroradial joint drive gear, 608-Third radial drive wheel, 609-Fourth radial drive wheel, 610-Humeral connecting shaft, 611-Third elbow joint cable drive interface, 612-Guide wheel; 6011-First humeralradial joint axis, 6021-Second humeralradial joint axis, 6061-Third humeralradial joint axis, 6101-Fourth humeralradial joint axis;

[0064] 701-Wrist planetary carrier, 702-First wrist sun gear, 703-Second wrist sun gear, 704-Output planetary gear, 705-First side cable guide device, 706-Second side cable guide device, 707-Distal ulna connector, 708-First wrist cable drive interface, 709-Second wrist cable drive interface, 710-Wrist central axis, 711-Tension adjusting spring, 712-Forearm pronation / supination axis, 713-Wrist guide wheel, 7011-First end connector, 7012-Second end connector, 7013-Third end connector, 7041-End output axis, 7051-First guide wheel carrier, 7052-First wrist drive wheel, 7061-Second guide wheel carrier, 7062-Second wrist drive wheel, 7101-Wrist central axis. Detailed Implementation

[0065] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0066] Example

[0067] like Figures 1-13 As shown, this embodiment provides a rear-drive bionic rope-driven upper limb robotic arm, including: a frame 1, a drive module 2, a rope-driven composite shoulder joint 3, an upper arm component 4, an ulna 5, a radius component 6, a wrist joint 7, and a rope sleeve 8.

[0068] All drive modules 2 of the cable-driven upper limb robotic arm are mounted on the frame 1. The cable-driven composite shoulder joint 3 is fixedly mounted on the frame 1. The upper arm component 4 is fixedly mounted on the output platform of the cable-driven composite shoulder joint 3. The ulna 5 is rotatably mounted to the upper arm component 4. The radius component 6 is rotatably mounted to the upper arm component 4. The wrist joint 7 is connected to the ulna 5 and the radius component 6 at the end of the robotic arm.

[0069] like Figure 3 As shown, the upper arm component 4 includes: a first upper arm side plate 401, a second upper arm side plate 402, a rocker arm 403, a drive rod 404, a transmission rod 405, a slider 406, a first elbow joint cable drive terminal 407, a second elbow joint cable drive terminal 408, an upper arm connecting plate 409, a humeroradial joint connector 410, and an antagonistic cable group guide wheel 411.

[0070] Specifically, referring to Figure 4, the first upper arm side plate 401 and the second upper arm side plate 402 are fixedly connected to the upper arm connecting plate 409. The first upper arm side plate 401 has bearings built into three hinge points, including the humeral joint rotation center 4011, the first hinge point 4012, and the fifth hinge point 4013. The drive rod 404 has three rotation centers, which are connected to other components respectively.

[0071] Furthermore, the ulna 5 is connected to the humeral joint rotation center 4011 of the first upper arm side plate 401, the drive rod 404 is rotatably connected to the first hinge point 4012 of the first upper arm side plate 401, and the two ends of the transmission rod 405 are rotatably connected to the drive rod 404 and the ulna 5 respectively. The rotation center is located at the second hinge point 4051 and the third hinge point 4052. The first upper arm side plate 401, the drive rod 404, the transmission rod 405, and the ulna 5 constitute a four-bar linkage. The four rotation centers are the humeral joint rotation center 4011, the first hinge point 4012, the second hinge point 4051, and the third hinge point 4052.

[0072] Specifically, the rocker arm 403 is rotatably connected to the first upper arm side plate 401 at the fifth hinge point 4013. A slide rail is mounted on the rocker arm 403, forming a sliding pair with the slider 406 via the slide rail. The slider 406 is rotatably connected to the drive rod 404 at the fourth hinge point 4041 of the drive rod 404. The slider 406 has a second guide wheel center 4061, on which a pulley is mounted. The first upper arm side plate 401, drive rod 404, slider 406, and rocker arm 403 constitute another four-bar linkage.

[0073] Furthermore, the end of the rocker arm 403 is equipped with a first elbow joint cable drive terminal 407, which has a third guide wheel center 4071 on it and is fitted with a pulley. The fifth hinge point 4013, the fourth hinge point 4041, the second guide wheel center 4061, and the third guide wheel center 4071 are located on the same straight line.

[0074] Furthermore, the drive rod 404, relative to the first hinge point 4012, has a first guide wheel center 4042 symmetrical to the fourth hinge point 4041, and a pulley is mounted on the first guide wheel center 4042. The vector connecting the fourth hinge point 4041 to the first hinge point 4012 is equal to the vector connecting the first guide wheel center 4042 to the first hinge point 4012 and is collinear at 180°.

[0075] Furthermore, a second elbow joint cable drive terminal 408 is mounted on the first upper arm side plate 401. The second elbow joint cable drive terminal 408, relative to the first hinge point 4012, has a fourth guide wheel center 4081 symmetrical to the fifth hinge point 4013. A pulley is mounted on the second elbow joint cable drive terminal 408 at the fourth guide wheel center 4081. The vector connecting the fifth hinge point 4013 to the first hinge point 4012 is equal to and collinear with the vector connecting the fourth guide wheel center 4081 to the first hinge point 4012, forming a 180° angle.

[0076] In this embodiment, the first elbow joint cable drive terminal 407 receives and transmits a rope from the drive module 2 via a winding connection. The rope is wound several turns, passes through the center of the third guide wheel 4071 and the center of the second guide wheel 4061, and is finally fixed to the end of the first elbow joint cable drive terminal 407. The second elbow joint cable drive terminal 408 receives and transmits a rope from the same drive module 2 via a reverse winding connection. The rope is wound several turns, passes through the center of the fourth guide wheel 4081 and the center of the first guide wheel 4042, and is finally fixed to the end of the second elbow joint cable drive terminal 408.

[0077] like Figure 4 As shown, the lines connecting the first hinge point 4012, the fourth hinge point 4041, and the fifth hinge point 4013 form a triangle, and the lines connecting the first hinge point 4012, the center of the first guide wheel 4042, and the center of the fourth guide wheel 4081 form a triangle. Since the two triangles share a vertex and have two pairs of adjacent sides that are correspondingly equal and collinear, the length of the line connecting the fourth hinge point 4041 and the fifth hinge point 4013 is equal to the length of the line connecting the centers of the first guide wheel 4042 and the fourth guide wheel 4081.

[0078] Specifically, the center 4071 of the third guide wheel and the fifth hinge point 4013 are located at the two ends of the rocker arm 403. Obviously, the length constraint of the component itself ensures that the length of the line connecting the center 4071 of the third guide wheel and the fifth hinge point 4013 remains constant. Similarly, the length of the line connecting the fourth hinge point 4041 on the slider 406 and the center 4061 of the second guide wheel remains constant. Subtracting the two, the sum of the lengths of the lines connecting the fourth hinge point 4041 and the fifth hinge point 4013 and the lengths of the lines connecting the centers 4061 of the second guide wheel and the center 4071 of the third guide wheel remains constant.

[0079] By replacing the length relationship, the sum of the length of the line connecting the center of the first guide wheel 4042 and the center of the fourth guide wheel 4081 and the length of the line connecting the center of the second guide wheel 4061 and the center of the third guide wheel 4071 remains constant. This ensures that the length of the rope with a certain number of turns passing between the center of the first guide wheel 4042 and the center of the fourth guide wheel 4081 is always equal to the length of the rope with the same number of turns passing between the center of the second guide wheel 4061 and the center of the third guide wheel 4071. This maintains the antagonistic relationship between the rope lengths entering the two terminals and the complementary relationship between growth and scaling.

[0080] Furthermore, when the rope passing through the first elbow joint cable drive terminal 407 is retracted, the length of the line connecting the center of the second guide wheel 4061 and the center of the third guide wheel 4071 decreases, causing the drive rod 404 to rotate, and the corresponding ulna 5 is lifted to complete the elbow flexion movement. Conversely, when the rope passing through the second elbow joint cable drive terminal 408 is retracted, the length of the line connecting the center of the first guide wheel 4042 and the center of the fourth guide wheel 4081 decreases, causing the drive rod 404 to rotate in the opposite direction, and the corresponding ulna 5 is lowered to complete the elbow extension movement.

[0081] like Figure 5 , Figure 10 As shown, the radius component 6 includes: a radius connecting rod 601, a first radius ball joint seat 602, a gear ring 603, a first radius drive wheel 604, a second radius drive wheel 605, a second radius ball joint seat 606, a humeroradial joint drive gear 607, a third radius drive wheel 608, two fourth radius drive wheels 609, a humeral connecting shaft 610, two third elbow joint cable drive interfaces 611 and guide wheels 612.

[0082] Specifically, the radial link 601 is rotatably connected to the first radial ball joint 602, with the center of rotation located on the first humeroradial joint axis 6011, that is, on the axis along the length of the radial link 601. The first radial ball joint 602 also has a second humeroradial joint axis 6021, and the first humeroradial joint axis 6011 and the second humeroradial joint axis 6021 on the first radial ball joint 602 always intersect perpendicularly.

[0083] like Figure 10 , Figure 11 As shown, the second radial ball support 606 has two perpendicularly intersecting rotational axes, namely the third humeroradial joint axis 6061 and the fourth humeroradial joint axis 6101. The intersection point of the axes on the first radial ball support 602 and the second radial ball support 606 is the same point. The first radial ball support 602 and the second radial ball support 606 are rotatably connected, and the third humeroradial joint axis 6061 is aligned with the second humeroradial joint axis 6021. A humeroradial joint drive gear 607 is rotatably connected on this axis, maintaining a rotatable connection with both the first and second radial ball supports 602 and 606. The third radial drive wheel 608 is fixedly connected to the humeroradial joint drive gear 607. The humeral connecting shaft 610 is rotatably connected to the second radial ball support 606 on the fourth humeroradial joint axis 6101. The humeral connecting shaft 610 is fixedly connected to the humeroradial joint connector 410 and indirectly fixedly connected to the second upper arm side plate 402.

[0084] In this embodiment, the first radial ball joint 602 and the second radial ball joint 606 form a ball joint, which restricts the movement between the upper arm component 4 and the radial link 601. The separate components can reduce interference and achieve a larger range of motion, presenting a function similar to the human humeroradial joint, which is a ball-and-socket joint composed of the radial glenoid fossa and the humeral head.

[0085] It is understandable that the upper arm component 4 and the radial link 601 are not limited to this assembly form. All structural schemes that satisfy the ball joint motion have the same degree of freedom. For example, the upper arm component 4 can be connected to the radial link 601 through a joint ball bearing, a fisheye bearing, or a ball joint composed of a universal joint and a revolute joint.

[0086] Specifically, the humeroradial joint drive gear 607 drives the gear ring 603 to rotate, thereby increasing the torque. The gear ring 603 is fixedly connected to the first radius drive wheel 604, and the radius connecting rod 601 is fixedly connected to the second radius drive wheel 605.

[0087] In this embodiment, optionally, two third elbow joint cable drive interfaces 611 are fixedly mounted on the second radial ball sub-seat 606 to receive and transmit two cables connected by the same drive module 2. These cables pass around the two fourth radial drive wheels 609 located on the second radial ball sub-seat 606 in opposite directions and are finally fixed on the third radial drive wheel 608, thereby driving the humeroradial joint drive gear 607 to rotate.

[0088] In this embodiment, on the internal / external rotation of the radial link 601, optionally, there are two oppositely oriented rope windings on the first radial drive wheel 604. After passing through the guide wheel 612, they are wound in opposite directions on the second radial drive wheel 605, driving the radial link 601 to rotate around the axis 6011 of the first humeroradial joint.

[0089] like Figure 6 , Figure 7 As shown, the wrist joint 7 includes: a wrist planetary carrier 701, a first wrist sun gear 702, a second wrist sun gear 703, an output planetary gear 704, a first side cable guide device 705, a second side cable guide device 706, a distal ulna connector 707, a first wrist cable drive interface 708, a second wrist cable drive interface 709, a wrist central shaft 710, a tension adjusting spring 711, and a wrist guide wheel 713.

[0090] Specifically, the wrist planetary carrier 701 is fixedly assembled from a first end connecting frame 7011, a second end connecting frame 7012, and a third end connecting frame 7013. The wrist planetary carrier 701 is rotatably connected to the wrist central shaft 710, which has a keyway that is fixedly connected to the first side wire guide device 705, the second side wire guide device 706, and the radial connecting rod 601. The wrist central shaft 710 is rotatably connected to the first wrist sun gear 702 and the second wrist sun gear 703. The distal ulna connector 707 is rotatably connected to the ulna 5 via a bearing and to the wrist central shaft 710 via a radial joint bearing, so that the ulna 5 is connected to the wrist central shaft 710 via a ball joint. The output planetary gear 704 is rotatably connected to the wrist planetary carrier 701.

[0091] In this embodiment, optionally, wrist guide wheels 713 are provided on the first end connecting frame 7011 and the second end connecting frame 7012 for internal / external rotation of the radial connecting rod 601. The wrist central shaft 710, the first wrist sun gear 702, the wrist planetary carrier 701, and the output planetary gear 704 constitute a planetary gear system. The first wrist sun gear 702 has two oppositely oriented rope windings, which, after being transmitted through the wrist guide wheel 713, are wrapped and fixedly connected to the output planetary gear 704. The total wrapping angle between the first wrist sun gear 702 and the output planetary gear 704 should be greater than 360°.

[0092] Similarly, the wrist central shaft 710, the second wrist sun gear 703, the wrist planetary carrier 701, and the output planetary gear 704 constitute the second planetary gear train. The second wrist sun gear 703 has two oppositely oriented rope windings, which, after being transmitted through the wrist guide wheel 713, are wrapped and fixed to the output planetary gear 704. The total wrapping angle between the first wrist sun gear 702 and the output planetary gear 704 should be greater than 360°. The rope drive has no lateral backlash compared to the gears, resulting in better transmission smoothness.

[0093] In some embodiments provided by the invention, the transmission method of the first wrist sun gear 702, the second wrist sun gear 703 and the output planetary gear 704 is not limited to passing over the wrist guide wheel 713, but also includes a spatial figure-eight winding method, that is, the shape of the transmission wheel is not limited to a cylindrical boss, but can be a conical boss, and the ropes meet once at the critical point of the conical boss.

[0094] Specifically, a first wrist drive wheel 7052 is fixed on the first guide wheel frame 7051 of the first side cable guide device 705. The first wrist rope drive interface 708 receives and transmits two ropes connected by the same drive module 2. After passing through the first wrist drive wheel 7052, the ropes are wrapped around the first wrist sun wheel 702 in opposite directions. The anchor point position of the rope fixation supports that it can rotate 180° in at least two directions respectively.

[0095] Similarly, a second wrist drive wheel 7062 is fixed on the second guide wheel frame 7061 of the second side cable guide device 706. The second wrist rope drive interface 709 receives and transmits two ropes connected by the same drive module 2. After passing through the second wrist drive wheel 7062, they are wrapped around the second wrist sun wheel 703 in opposite directions. The anchor point position of the rope fixation supports that it can rotate 180° in at least two directions respectively.

[0096] In this embodiment, the first wrist cable drive interface 708 and the first side cable guide device 705 are fixed together by screws, and a tension adjusting spring 711 is fitted onto the screws. The second wrist cable drive interface 709 and the second side cable guide device 706 are assembled in the same way. This allows the length of the externally introduced cable to be adjusted, changing the output stiffness to the external environment and further improving the interaction compliance.

[0097] In addition to the stiffness adjustment measures in this embodiment, the present invention can also achieve passive stiffness adjustment in specific joint movement areas by adding a spring between the motor or reducer of the drive module 2 and the winding shaft.

[0098] In this embodiment, the output planetary gear 704 can rotate around the end output axis 7041. The end output axis 7041 and the wrist center axis 7101 on the wrist center axis 710 are always perpendicularly intersecting each other. The output planetary gear 704 can simultaneously revolve around the wrist planetary carrier 701 relative to the wrist center axis 7101.

[0099] Specifically, the first and second arm sun gears are all connected to the output planetary gears, forming a differential gear train. The output planetary gears and the two arm sun gears are driven by ropes. By controlling the rotational direction of the arm sun gears, the planetary gears can achieve both revolution and rotation (two degrees of freedom). When the two arm sun gears rotate in the same direction at the same speed, the arm planetary carrier revolves while the output planetary gears do not rotate. When the two arm sun gears rotate in opposite directions at the same speed, the output planetary gears rotate while the arm planetary carrier does not revolve.

[0100] It should be noted that the upper arm component 4, ulna 5, radius component 6, and wrist joint 7 constitute a spatial four-bar linkage with revolute joints, ball joints, revolute joints, and ball joints as vertices in sequence. The line connecting the center points of the two ball joints forms a forearm pronation / supination axis 712. Rotation around this axis is a permitted degree of freedom, allowing the distal end of the wrist joint 7 to rotate relative to the forearm pronation / supination axis 712. Furthermore, this pronation / supination corresponds one-to-one with the rotation of the radial link 601. In other words, the set of rotational movements of the radial link 601 around the first humeroradial joint axis 6011 always has a unique mapping relationship with the set of pronation / supination movements of the radius component 6 relative to the ulna 5, and vice versa. Therefore, driving the radial link 601 to rotate around the first humeroradial joint axis 6011 can effectively achieve remotely driven pronation / supination movements of the distal end of the wrist joint 7.

[0101] The forearm pronation / supination axis 712, which dominates the rotation of the radial link 601, and the wrist center axis 7101 of the differential gear train inside the wrist joint 7, and the end output axis 7041, all three axes always converge at one point, ensuring that the end of the robotic arm, such as the manipulator or chuck connected to the output planetary gear 704, can output three degrees of freedom motion.

[0102] In this embodiment, the diameter of the sleeve and the diameter of the driving rope have a certain gap, which limits the friction during transmission to a certain range, and the rope inside the sleeve will not have excessive relative deformation, and its length always approaches the constant length of the sleeve, thus improving positioning accuracy. Several sleeves are respectively connected to the first elbow joint rope drive terminal 407, the second elbow joint rope drive terminal 408, the third elbow joint rope drive interface 611, the first wrist rope drive interface 708, and the second wrist rope drive interface 709.

[0103] like Figure 1 , Figure 12 , Figure 13 As shown, the existing cable-driven composite shoulder joint 3 included in the robotic arm of this embodiment is a cable-driven dual parallel mechanism with five degrees of freedom, and the hybrid mechanism from the cable-driven composite shoulder joint 3 to the wrist joint 7 has four degrees of freedom, so that the robotic arm has a total of nine degrees of freedom.

[0104] like Figure 12 As shown, in this embodiment, the range of motion of the ulna 5 and radius component 6 relative to the upper arm flexion is not less than 120°.

[0105] like Figure 13 As shown, in this embodiment, the radial component 6 is pronated / supinated relative to the ulna 5 by at least ±90°.

[0106] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A biomimetic cable-driven upper limb robotic arm with a rear-mounted actuator, characterized in that, include: Frame, drive module, cable-driven composite shoulder joint, upper arm components, ulna, radius components, wrist joint; The drive module and the cable-driven composite shoulder joint are connected to the frame. The drive module is connected to the cable-driven composite shoulder joint. The cable-driven composite shoulder joint is connected to the upper arm component. The upper arm component is movably connected to the ulna and radius component. The ulna and radius component is connected to the wrist joint. The wrist joint is equipped with a wrist sun gear, an output planet gear, a wrist planet carrier, and a wrist central shaft. The wrist planet carrier is rotatably connected to the wrist central shaft, the wrist central shaft is rotatably connected to the wrist sun gear, the output planet gear is rotatably connected to the wrist planet carrier, and the wrist sun gear and the output planet gear are differentially connected. The drive module outputs ropes that are wound in both directions, driving the upper arm component to move the ulna to complete elbow flexion and extension movements, driving the radius component to rotate, driving the wrist sun gear to drive the output planetary gear to rotate, and driving the wrist sun gear to drive the wrist planetary carrier to rotate around the axis of the wrist center axis.

2. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 1, characterized in that, The upper arm components include the upper arm side plate, transmission rod, drive rod, and rocker arm; The upper arm lateral plate has the humeroulnar joint rotation center, the first hinge point, and the fifth hinge point. One end of the rocker is connected to the fifth hinge point. The rocker body is equipped with a slide rail, and a slider is provided on the slide rail to form a sliding pair. The end of the ulna is connected to the rotation center of the humeroulnar joint, and the extended part of the end of the ulna is movably connected to one end of the transmission rod to form a third hinge point; The middle part of the drive rod is connected to the first hinge point, and the two ends of the drive rod are connected to the other end of the transmission rod and the slider, respectively, forming the second hinge point and the fourth hinge point; The drive module drives the slider to slide on the slide rail via a rope, which in turn drives the drive rod to rotate, and the corresponding ulna is lifted to complete the elbow flexion movement. The drive module drives the drive rod to rotate in the opposite direction via a rope, and the corresponding ulna is lowered to complete the elbow extension movement.

3. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 2, characterized in that, The slider has a second guide wheel center, and the second guide wheel center has a pulley; The end of the joystick is provided with a first elbow joint cable drive terminal, the first elbow joint cable drive terminal is provided with a third guide wheel center, and the third guide wheel center is provided with a pulley; Relative to the first hinge point, the drive rod is provided with a first guide wheel center symmetrical to the fourth hinge point, and the first guide wheel center is provided with a pulley; The upper arm side plate is provided with a second elbow joint cable drive terminal. Relative to the first hinge point, the second elbow joint cable drive terminal is provided with a fourth guide wheel center symmetrical to the fifth hinge point. The fourth guide wheel center is provided with a pulley. The first elbow joint cable drive terminal receives the cable connected to the drive module winding, passes through the center of the third guide wheel and the center of the second guide wheel, and is finally fixed at the end of the first elbow joint cable drive terminal. When the cable of the first elbow joint cable drive terminal is retracted, the length of the line connecting the center of the second guide wheel and the center of the third guide wheel decreases, which drives the drive rod to rotate, and the corresponding ulna is lifted to complete the elbow flexion movement. The second elbow joint cable drive terminal receives a cable connected to the same drive module in the opposite direction. The cable passes through the center of the fourth guide wheel and the center of the first guide wheel, and is finally fixed at the end of the second elbow joint cable drive terminal. When the cable passing through the second elbow joint cable drive terminal is retracted, the length of the line connecting the center of the first guide wheel and the center of the fourth guide wheel decreases, causing the drive rod to rotate in the opposite direction. The corresponding ulna is lowered to complete the elbow extension movement.

4. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 1, characterized in that, The radial component includes: a radial connecting rod, a first radial ball joint seat, a gear ring, a first radial drive wheel, a second radial drive wheel, a second radial ball joint seat, a humeroradial joint drive gear, and a third radial drive wheel; The radial link is connected to the upper arm component, the radial link is rotatably connected to the first radial ball joint seat, and the first radial ball joint seat is rotatably connected to the second radial ball joint seat and the humeroradial joint drive gear. The third radial drive wheel is fixedly connected to the humeroradial joint drive gear, which meshes with a gear ring. The gear ring is fixedly connected to the first radial drive wheel, and the radial connecting rod is fixedly connected to the second radial drive wheel. The first radial drive wheel is connected to the second radial drive wheel via a rope. The first and second radial ball joints form a ball joint, which restricts the movement between the upper arm components and the radial link. The drive module drives the third radial drive wheel to rotate, the third radial drive wheel drives the humeroradial joint drive gear to rotate, the humeroradial joint drive gear drives the gear ring to rotate, the gear ring drives the first radial drive wheel to rotate, the first radial drive wheel drives the second radial drive wheel to rotate, and the second radial drive wheel drives the radial connecting rod to rotate.

5. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 4, characterized in that, The upper arm component is also equipped with a humeroradial joint connector, and the radial link is also equipped with a humeral connecting shaft; The humeral connecting shaft is rotatably connected to the second radial ball joint, and the humeral connecting shaft is fixedly connected to the humeroradial joint connector of the upper arm component.

6. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 4, characterized in that, The second radial ball joint is equipped with two third elbow joint cable drive interfaces and a fourth radial drive wheel. It receives two cables from the same drive module and connects them by winding. The cables pass around the two fourth radial drive wheels located on the second radial ball joint in opposite directions and are finally fixed on the third radial drive wheel, driving the humeroradial joint drive gear to rotate.

7. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 4, characterized in that, The first radial ball joint is equipped with a guide wheel, and two oppositely oriented rope windings are connected to the first radial drive wheel. After passing through the guide wheel, the ropes are wound in opposite directions onto the second radial drive wheel. The first radial drive wheel drives the second radial drive wheel to rotate, and the second radial drive wheel drives the radial connecting rod to rotate.

8. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 1, characterized in that, The wrist joint includes: the first wrist sun chakra and the second wrist sun chakra; The wrist central axis is fixedly connected to the radius component, the wrist central axis is connected to the ulnar ball joint, the wrist central axis is rotatably connected to the first wrist sun gear and the second wrist sun gear, and the output planetary gear is rotatably connected to the wrist planetary carrier. The first arm sun gear, the second arm sun gear, and the output planet form a differential transmission relationship; The first arm sun gear has two oppositely oriented rope windings, which are wrapped around and fixed to the output planet gear; The second arm sun gear has two oppositely oriented rope windings, which are wrapped around and fixed to the output planet gear; The two sides of the wrist planetary carrier are respectively provided with wrist guide wheels. The rope windings of the first wrist sun gear and the second wrist sun gear are transmitted through the corresponding wrist guide wheels and then wrapped and fixed on the output planetary gear.

9. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 8, characterized in that, The wrist central shaft is provided with a keyway, and is also connected to a first side wire guide device and a second side wire guide device respectively; The first side cable guide device is provided with a first guide wheel frame, the first guide wheel frame is provided with a first wrist transmission wheel, and the first side cable guide device is connected to a first wrist rope drive interface. The first wrist rope drive interface receives two ropes connected to the drive module winding, which are then wrapped around the first wrist sun gear in opposite directions after passing through the first wrist transmission wheel; The second side cable guide device is equipped with a second guide wheel frame, and the second guide wheel frame is equipped with a second wrist drive wheel. The second side cable guide device is connected to a second wrist rope drive interface. The second wrist cable drive interface receives two cables connected to the drive module winding, which, after passing through the second wrist transmission wheel, are wrapped around the second wrist sun wheel in opposite directions.

10. The bionic rope-driven upper limb robotic arm with rear-mounted drive according to claim 8, characterized in that, A stiffness adjustment device is provided and fixedly connected between the first wrist rope drive interface and the first side cable guide device, and a stiffness adjustment device is provided and fixedly connected between the second wrist rope drive interface and the second side cable guide device, so that the rope tension at the far end can be adjusted.

Images