Robot joint module

Abstract

The invention relates to the field of machinery, and discloses a robot joint module which comprises a first joint driving unit, a second joint driving unit and a joint output unit, and the first joint driving unit comprises a first shifting fork structure, a first hobbing, a first driving part, a second driving part and a first shell assembly; the second joint driving unit comprises a second shifting fork structure, a second hobbing, a third driving part, a fourth driving part and a second shell assembly; the joint output unit comprises a third shell assembly and spherical teeth. High integration and three-dimensional attitude output can be achieved, output of the first joint driving unit and output of the second joint driving unit are relatively independent and do not interfere with each other, driving superposition and cooperative driving are carried out in different directions, and finally multi-degree-of-freedom continuous controllable output is achieved. And through cooperation, synchronous constraint and mutual coordination among all the components can be realized, meshing impact caused by single-drive advance is further reduced, and stable tracking of multi-degree-of-freedom postures is realized.

Description

Technical Field

[0001] This invention relates to the field of mechanics, and in particular to a robot joint module. Background Technology

[0002] With the rapid development of humanoid robots in service, medical, and industrial fields, the performance requirements for robot joint modules of robotic arms (i.e., manipulators) are increasing, especially in terms of range of motion, precision, integration, and structural compactness. Existing robot joint modules mostly fall into two categories: rotary joint modules and linear joint modules. Both structures have their advantages and disadvantages, but they still have certain limitations in achieving complex and precise human-inspired movements.

[0003] Rotary joint modules typically combine with motors via reducers (such as planetary reducers and harmonic reducers) to provide high torque output, meeting the high load and torque requirements of robotic arms. However, they usually only possess a single rotational degree of freedom, meaning each joint can only rotate around a fixed axis. To simulate complex multi-degree-of-freedom joint movements, at least two rotary joint modules are usually used in series, especially when simulating multi-degree-of-freedom ball-and-socket joints such as the shoulder and hip joints, where existing rotary joint modules often fail to provide ideal range of motion and accuracy. Linear joint modules combine with motors via lead screws, converting rotational motion into linear motion to simulate the contraction and extension of human muscles. Although linear joint modules achieve high space utilization, their capabilities in multi-degree-of-freedom motion are limited, making them unable to effectively simulate ball-and-socket joint movements requiring multiple rotational degrees of freedom, such as the shoulder and hip joints. While performing well in some applications, the single-degree-of-freedom structure of linear joint modules prevents them from providing more precise and flexible motion control when achieving complex three-dimensional motion. Therefore, in addressing the complex and biomimetic motion requirements of humanoid robots, problems such as insufficient degrees of freedom and low integration remain. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a robot joint module to solve the problems of insufficient degrees of freedom and low integration of existing joint modules.

[0005] To solve the above-mentioned technical problems, one technical solution adopted by the present invention is: providing a robot joint module including: a first joint driving unit, a second joint driving unit, and a joint output unit. The first joint driving unit includes a first fork structure, a first hob connected to the first fork structure, a first driving part connected to the first fork structure and used to drive the first fork structure to rotate around a first direction for output, a second driving part connected to the first fork structure and used to drive the first hob on the first fork structure to rotate around a second direction for output, and a first housing assembly fitted onto the first driving part; the second joint driving unit includes a second fork structure, a first hob connected to the first fork structure, a first driving part connected to the first fork structure and used to drive the first hob on the first fork structure to rotate around a second direction for output, and a first housing assembly fitted onto the first driving part; the second joint driving unit includes a second fork structure, a first driving part connected to the first driving part, a first driving part connected to the first fork structure and used to drive the first hob on the first fork structure to rotate around a second direction for output, and a first housing assembly fitted onto the first driving part; The joint output unit comprises a second hob connected to the second shift fork structure, a third drive unit connected to the second shift fork structure and used to drive the second shift fork structure to rotate around a third direction, a fourth drive unit connected to the second shift fork structure and used to drive the second hob to rotate around a fourth direction, and a second housing assembly fitted onto the second shift fork structure and the third drive unit; the joint output unit includes a third housing assembly connected to the first housing assembly and the second housing assembly respectively, and a spherical tooth movable in the third housing assembly and respectively driven and engaged with the first hob and the second hob, the spherical tooth having an output end that outputs power with multiple degrees of freedom when the first hob and the second hob rotate.

[0006] Furthermore, the first joint drive unit is arranged along a first direction, and the second joint drive unit is arranged along a third direction; the first joint drive unit is shorter than the second joint drive unit.

[0007] Furthermore, the first shift fork structure includes a first base and two first transmission arms connected to the first base and arranged along a second direction. The first drive unit is mounted on the first base and surrounds the first transmission arms. The second drive unit is mounted between the two first transmission arms. The second shift fork structure includes a second base and two second transmission arms connected to the second base and arranged along a fourth direction. An extension shaft is formed on the second base extending along a third direction. The third drive unit is coaxially mounted on the extension shaft. The fourth drive unit is mounted between the two second transmission arms.

[0008] Furthermore, the first drive unit includes a first rotor positioned and mounted on the first shift fork structure and a first stator surrounding the first rotor. A first magnetic encoder and a first magnetic ring are mounted on the first rotor. The first housing assembly includes a first housing rotatably mounted on the outer periphery of the first rotor and a first rear cover rotatably mounted on the outer periphery of the first rotor and coaxially connected to the first housing. The first stator is installed inside the first housing. The first housing has a first output port for a portion of the first hobbing gear to extend out. A first bearing is provided between the first housing and the first rotor to cause the first rotor to rotate relative to the first housing. A second bearing is provided between the first rear cover and the first rotor to cause the first rotor to rotate relative to the first rear cover. A first preload space is formed between the second bearing, the first rotor, and the first rear cover. A first spring is provided in the first preload space to elastically abut against the second bearing and the first rear cover in a first direction. The first spring is configured as a first wave spring.

[0009] Furthermore, the third drive unit includes a third rotor positioned and mounted on the second shift fork structure and a third stator surrounding the third rotor. A third magnetic encoder and a third magnetic ring are mounted on the third rotor. The second housing assembly includes a second housing rotatably mounted on the outer periphery of the second shift fork structure and a second rear cover rotatably mounted on the outer periphery of the second shift fork structure and coaxially connected to the second housing. The third stator is installed inside the second housing. The second housing has a second output port for a portion of the second hobbing gear to extend out. A third bearing is provided between the second housing and the second shift fork structure to cause the second shift fork structure to rotate relative to the second housing. A fourth bearing is provided between the second rear cover and the second shift fork structure to cause the second shift fork structure to rotate relative to the second rear cover. A second preload space is formed between the fourth bearing, the second shift fork structure, and the second rear cover. A second spring is provided in the second preload space, elastically pressing against the fourth bearing and the second rear cover in a third direction. The second spring is configured as a second wave spring.

[0010] Furthermore, the first rear cover has a first wall surface connected to the outer ring of the second bearing, and the first rotor has a first mating surface connected to the inner ring of the second bearing and abutting against the side of the second bearing away from the second spring in the first direction; the second rear cover has a second wall surface connected to the outer ring of the fourth bearing, and one end of the second shift fork structure has a second mating surface connected to the inner ring of the fourth bearing and abutting against the side of the fourth bearing away from the second spring in the first direction.

[0011] Furthermore, each of the two first transmission arms has a first connecting surface on its opposite side. The second drive unit includes a first fixed seat with both ends connected to the two first connecting surfaces, a second stator mounted on the first fixed seat, and a second rotor movably mounted around the second stator. The first transmission arm is equipped with a second magnetic encoder. A fifth bearing is provided between the two ends of the second rotor and the two ends of the fixed seat to allow the second rotor to rotate relative to the first fixed seat. The first hobbing gear is mounted on the second rotor and connected to the fifth bearing. Each of the two second transmission arms has a second connecting surface on its opposite side. The fourth drive unit includes a second fixed seat with both ends connected to the two second connecting surfaces, a fourth stator mounted on the second fixed seat, and a fourth rotor movably mounted around the fourth stator. The second transmission arm is equipped with a fourth magnetic encoder. A sixth bearing is provided between the two ends of the fourth rotor and the two ends of the second fixed seat to allow the fourth rotor to rotate relative to the second fixed seat. The second hobbing gear is mounted on the fourth rotor and connected to the sixth bearing.

[0012] Furthermore, the robot joint module of the present invention also includes a first wiring channel and a second wiring channel; the first wiring channel includes a first channel formed in the first fixed base and connected to the second stator and a second channel connected to the first channel and formed to the first shift fork structure, and the first joint drive unit also includes a first conductive slip ring connected to the first housing assembly and connected to the second channel in a first direction; the second wiring channel includes a third channel formed in the second fixed base and connected to the fourth stator and a fourth channel connected to the third channel and formed to the second shift fork structure, and the second joint drive unit also includes a second conductive slip ring connected to the second housing assembly and connected to the fourth channel in a third direction.

[0013] Furthermore, the surface of the spherical tooth has a spherical surface, and the spherical surface is covered with a plurality of meshing teeth, and any two adjacent meshing teeth are distributed circumferentially along the spherical surface; the outer walls of the first and second hobs are each formed with strip teeth that are distributed circumferentially around their respective axes and are used for meshing, coupling and sliding with the meshing teeth; the strip teeth have a first curved tooth edge that is concave in the middle along the length direction.

[0014] Furthermore, a multi-layered annular first ring tooth is formed on one side of the outer peripheral wall of both the first and second hobs. A plurality of transition tooth bands are formed along the circumference of the spherical tooth, which are coupled with the strip tooth and mesh with the first ring tooth. At least two second ring teeth are formed on the transition tooth band, which are respectively slidably engaged with the first ring tooth and used for coupling with the strip tooth. The first ring tooth has a second curved tooth edge that is spaced apart from the transition tooth band in the circumferential direction of the corresponding hob. A third output port is formed on the third housing assembly, which allows the output end of the spherical tooth to move through. The third output port has a surrounding edge that simulates the rotation angle of the ball and socket to limit the rotation range of the output end.

[0015] Furthermore, the first ring tooth includes a tooth protrusion and an annular tooth disposed around the outer periphery of the tooth protrusion. The annular tooth has a plurality of continuous annular teeth and a plurality of discontinuous annular teeth symmetrically disposed on both sides of the outer periphery of each continuous annular tooth. An arc-shaped tooth groove is formed between adjacent tooth protrusions and continuous annular teeth, between two adjacent continuous annular teeth, between adjacent continuous annular teeth and discontinuous annular teeth, and between two adjacent discontinuous annular teeth. With the tooth protrusion as the center, the curvature of each discontinuous annular tooth gradually decreases outwards.

[0016] Furthermore, the transition toothed band includes a plurality of long teeth adapted to the strip teeth and distributed sequentially along the circumference. The long teeth are used for meshing and sliding with the strip teeth. The long teeth between any two adjacent second ring teeth are arranged from one side of the second ring teeth toward the center, gradually increasing in length. Each long tooth has a relatively distributed arc-shaped guide surface on both sides, and the curvature directions of the two arc-shaped guide surfaces are respectively distributed in the circumferential direction where the two spherical teeth intersect.

[0017] The robot joint module of the present invention has at least the following beneficial effects: through the cooperation of the first joint drive unit and the joint output unit, the output end can realize rotational output in the first and second directions; through the cooperation of the second joint drive unit and the joint output unit, the output end can realize rotational output in the third and fourth directions, ultimately enabling the output end to achieve three-dimensional posture output similar to ball-and-socket joints such as the human shoulder / hip joint; and through the mutual connection and cooperation of the first housing assembly, the second housing assembly and the third housing assembly, the first to fourth drive units are highly integrated, making the entire robot joint module simpler; and the outputs of the first joint drive unit and the second joint drive unit are relatively independent and do not interfere with each other, but drive superposition and cooperative drive are performed in different directions, ultimately achieving continuous and controllable output of multiple degrees of freedom. The cooperative cooperation enables synchronous constraints and mutual coordination between the components, further reducing the meshing impact caused by single drive first, and achieving stable tracking of multi-degree-of-freedom posture. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the structure of an embodiment of the robot joint module of the present invention; Figure 2 This is a top sectional view of an embodiment of the robot joint module of the present invention; Figure 3 This is a schematic diagram of a robot joint module according to an embodiment of the present invention. The diagram shows a perspective view after the third housing assembly is hidden. Figure 4 This is a schematic diagram of the structure of the first joint drive unit in an embodiment of the robot joint module of the present invention. The diagram shows the three-dimensional structure of the first joint drive unit after one-quarter of it has been cut off. Figure 5 This is a side sectional view of the first joint drive unit in an embodiment of the robot joint module of the present invention. Figure 6 This is an exploded view of the first joint drive unit in an embodiment of the robot joint module of the present invention. The view shows the second drive part, the first fork structure and the first hobbing gear assembly state of the first joint drive unit. Figure 7 This is a schematic diagram of the structure of the first fork in one embodiment of the robot joint module of the present invention; Figure 8 This is a half-sectional schematic diagram of the first fork structure and the first drive unit in one embodiment of the robot joint module of the present invention. Figure 9 This is a cross-sectional view of the first fork structure, the first drive unit, and the first housing assembly in one embodiment of the robot joint module of the present invention; Figure 10 This is an exploded cross-sectional view of the first housing assembly in one embodiment of the robot joint module of the present invention; Figure 11 This is a front sectional view of the first fork structure, the first hob, and the second drive unit in an embodiment of the robot joint module of the present invention. Figure 12 An exploded view of the second drive unit and the first hobbing gear in one embodiment of the robot joint module of the present invention; Figure 13 This is a schematic diagram of the structure of the first hobbing gear in one embodiment of the robot joint module of the present invention; Figure 14 This is a schematic diagram of the structure of the second joint drive unit in one embodiment of the robot joint module of the present invention; Figure 15This is a side sectional view of the second joint drive unit in one embodiment of the robot joint module of the present invention. Figure 16 An exploded view of the second joint drive unit in one embodiment of the robot joint module of the present invention; Figure 17 This is a schematic diagram of the second fork structure in one embodiment of the robot joint module of the present invention; Figure 18 This is a half-sectional schematic diagram of the second fork structure and the third drive unit in one embodiment of the robot joint module of the present invention. Figure 19 This is an exploded view of the second fork structure and the fourth drive unit in one embodiment of the robot joint module of the present invention; Figure 20 This is a schematic diagram of the second fork structure and the fourth drive unit in one embodiment of the robot joint module of the present invention; Figure 21 This is a front sectional view of the joint output unit and the first joint drive unit in one embodiment of the robot joint module of the present invention; Figure 22 This is a side sectional view of the joint output unit and the second joint drive unit in one embodiment of the robot joint module of the present invention. Figure 23 This is a schematic diagram of the joint output unit in one embodiment of the robot joint module of the present invention; Figure 24 This is a top view of the joint output unit in one embodiment of the robot joint module of the present invention; Figure 25 This is a schematic diagram of the spherical tooth structure in one embodiment of the robot joint module of the present invention; Figure 26 This is a diagram showing the state changes of the first hob, the second hob, and the third hob in one embodiment of the robot joint module of the present invention. The diagram illustrates six state changes of the AF. Figure 27 This is a structural diagram of the first hobbing tooth, the second hobbing tooth, and the third hobbing tooth in one embodiment of the robot joint module of the present invention. The diagram shows the four state changes of GJ after F. The meanings of the labels in the attached diagram are as follows: First joint drive unit 1, first shift fork structure 11, first base 111, first end face 1111, second end face 1112, first transmission arm 112, clearance surface 1121, first mating surface 1131, first abutting surface 1132, first annular protrusion 1141, stepped surface 1142, first connecting surface 1151, first connecting hole 1152, first drive part 12, connecting side 12a, surrounding side 12b, first rotor 121, first surrounding section 1211, middle section 1212, second surrounding section 1213, first stator 122, first magnetic encoder 123, first magnetic ring 124, first housing assembly 13, first housing 131, first output port 1311, first bearing 1312, first groove 1313, second groove Body 1314, First rear cover 132, Third groove 1321, Second bearing 1322, Fourth groove 1323, First groove surface 13231, Second groove surface 13232, First spring 133, Second drive unit 14, First fixed seat 141, First end plate 1411, First central shaft 1412, Second end plate 1413, Second stator 142, Second rotor 143, Second magnetic encoder 144, Second magnetic ring 145, First protrusion 146, Fifth groove 1461, Fifth bearing 147, First wiring channel 15, First channel 151, First branch 1511, Second channel 152, First wiring channel 1521, First first channel 15211, Second second channel 15212, First mounting groove 15213. Second channel 1522, third channel 15221, channel opening 15222, first conductive slip ring 16, first hobbing gear 17, first strip tooth 171, first annular tooth 172, first tooth protrusion 1721, first ring tooth 1722, first continuous annular tooth 17221, first discontinuous annular tooth 17222, second joint drive unit 2, second shift fork structure 21, second base 211, third end face 2111, fourth end face 2112, second transmission arm 212, back face 2121, extension shaft 213, third surrounding section 213a, fourth surrounding section 213b, second mating surface 2131, second abutting surface 2132, third annular protrusion 2133, fourth annular protrusion 2134, second connecting surface 2141, second connecting hole 21 42. Third drive unit 22, third rotor 221, third stator 222, third magnetic encoder 223, third magnetic ring 224, second housing assembly 23, second housing 231, first housing segment 231a, second housing segment 231b, third housing segment 231c, second output port 2311, sixth slot 2312, inner extension edge 2313, seventh slot 2314, third bearing 2315, second rear cover 232, first inner extension ring 2321, fourth bearing 2322, eighth slot 2323, second spring 233, fourth drive unit 24, second fixed seat 241, third end plate 2411, second central shaft 2412, fourth end plate 2413, second protrusion 2414, ninth slot 2415, sixth bearing 2416.Fourth stator 242, fourth rotor 243, fourth magnetic encoder 244, fourth magnetic ring 245, second wiring channel 25, third channel 251, second branch 2511, fourth channel 252, third guideway 2521, fourth secondary channel 25211, fifth secondary channel 25212, second mounting slot 25213, fourth guideway 2522, sixth secondary channel 25221, seventh secondary channel 25222, second conductive slip ring 26, second gear hobbing 27, second strip tooth 27 1. Second annular tooth 272, second tooth protrusion 2721, second annular tooth 2722, joint output unit 3, third housing assembly 31, third housing 311, spherical cavity 312, first assembly surface 313, second assembly surface 314, first input port 315, second input port 316, third output port 317, perimeter 3171, spherical tooth 32, meshing tooth 321, transition toothed belt 322, long tooth 3221, second annular tooth 323, output end 324, flange shaft 3241. Detailed Implementation

[0019] The invention will now be further described with reference to the accompanying drawings.

[0020] Please see Figures 1 to 3 The robot joint module of the present invention includes a first joint drive unit 1, a second joint drive unit 2, and a joint output unit 3 that is respectively driven and coupled to the first joint drive unit 1 and the second joint drive unit 2.

[0021] Please see Figures 4 to 5The first joint drive unit 1 is arranged along a first direction, that is, the overall axial direction of the first joint drive unit 1 is distributed along the first direction. The first joint drive unit 1 includes a first shift fork structure 11, a first drive part 12 connected to the first shift fork structure 11 and used to drive the first shift fork structure 11 to rotate around a first direction, a first housing assembly 13 fitted onto the first drive part 12, a second drive part 14 connected to the first shift fork structure 11, a first wiring channel 15 formed on the first shift fork structure 11, a first conductive slip ring 16 connected to the first housing assembly 13, and a first hobbing gear 17 connected to the first shift fork structure 11. The first shift fork structure 11 provides connection support for the installation of the first drive part 12 and the second drive part 14, and highly integrates the first drive part 12 and the second drive part 14. The first housing assembly 13 provides protective support for the entire first joint drive unit 1, and is used to cooperate with the first drive part 12 to position the first shift fork structure 11 and the first drive part 12, so that they are fixed in the first housing assembly 13. The first hob 17 is used for rotation to output power. The first drive unit 12 and the second drive unit 14 enable the first hob 17 to output power in both a first and second direction. This achieves a combination of dual power outputs for the first hob 17, reducing redundant design and lowering costs and complexity to some extent, making the entire joint drive device simpler. It achieves multi-degree-of-freedom output within a smaller volume, optimizing space utilization. It ensures that the first and second direction rotations of the first hob 17 are independent, preventing power output interference and enabling precise control of the first shift fork structure 11 and the first hob 17. This allows for reliable output as needed, improving motion control accuracy. The simplified structure also reduces mechanical wear and maintenance costs. The first wiring channel 15 provides a rational layout for the wiring of the internal second drive unit 14, ensuring that all components operate as expected. The first conductive slip ring 16 works in conjunction with the first wiring channel 15 to achieve a rational wiring layout.

[0022] Please see Figures 6 to 8 The first shift fork structure 11 includes a first base 111 and two first transmission arms 112 connected to the first base 111 and spaced apart along a second direction. The first base 111 provides support for the first drive unit 12 and the first transmission arms 112. The first transmission arms 112 cooperate with the first base 111 to realize the integrated arrangement of the first drive unit 12 and the second drive unit 14.

[0023] The first base 111 can be configured as a block-shaped three-dimensional structure. In this embodiment, the first base 111 can be configured as a cylinder. In another embodiment, the first base 111 can also be configured as a cuboid or other geometric structures, but a relatively regular geometric shape such as a polygonal prism should be selected to facilitate batch processing and make the installation between the first base 111 and the first drive unit 12 easier. The center of the first base 111 is selected as a reference to give it an axial direction and a radial direction perpendicular to the axial direction. The first base 111 is axially configured as a first direction, and the direction corresponding to the first base 111 rotating around the axis of the first direction is defined as the circumferential direction of the first base 111. The first base 111 has a first end face 1111 and a second end face 1112 that are relatively distributed along the first direction. The first base 111 also has a first outer peripheral wall that is distributed around the first base 111 circumferentially.

[0024] The first base 111 has a first connecting structure for cooperating with the first driving part 12. The first connecting structure, through its connection with the first driving part 12, can drive the first base 111 to rotate circumferentially (i.e., in the first direction) and output power, thereby realizing the installation of the first driving part 12 and the driving of the first driving part 12 on the first base 111. The first connecting structure has a first mating surface 1131 and a first abutting surface 1132 formed on the first base 111. The first driving part 12 is fitted onto the first mating surface 1131 in the first direction to be installed on the first base 111. After being installed on the first base 111, the first driving part 12 abuts against the first abutting surface 1132 in the first direction to position the first driving part 12 and ensure that the first driving part 12 can be installed in place.

[0025] In one embodiment, the first mating surface 1131 is formed circumferentially on the first outer peripheral wall of the first base 111. When the first base 111 is cylindrical, the first mating surface 1131 can be annular. In another embodiment, when the first base 111 is cuboid or cube-shaped, the first mating surface 1131 is cuboid or cube-shaped and matches the contour of the first base 111. To facilitate the installation of the first driving part 12, the first mating surface 1131 is arranged to penetrate the first end face 1111 of the first base 111 along the first direction. Correspondingly, the first driving part 12 is provided with a hole structure that is consistent with or similar to the contour of the first mating surface 1131, so that the first driving part 12 can be fitted axially from the first end face 1111 onto the first mating surface 1131, i.e., onto the first base 111, and then connected by fixing means such as glue, welding, bolts, or rivets.

[0026] In this embodiment, the first abutting surface 1132 and the first mating surface 1131 are arranged at a certain angle, such as an acute angle, a right angle, or an obtuse angle, so that after the first driving part 12 is fitted onto the first mating surface 1131, one end face can abut against the first abutting surface 1132 in a first direction. In one embodiment, the first mating surface 1131 may be connected to the first abutting surface 1132. For example, a first annular protrusion 1141 is formed on the first outer peripheral wall, protruding radially outward relative to the first mating surface 1131 along the first base 111, and the first annular protrusion 1141 is located close to the second end face 1112 and away from the first end face 1111. The first annular protrusion 1141 may be distributed in a ring around the first outer peripheral wall in the circumferential direction of the first base 111. The first annular protrusion 1141 may also be configured as several arc-shaped protrusions, and the several first annular protrusions 1141 are equally spaced around the first outer peripheral wall in the circumferential direction of the first base 111. The first annular protrusion 1141 is adjacent to and connected to the first mating surface 1131 on the side of the first end face 1111 along the circumferential direction. The side of the first annular protrusion 1141 adjacent to the first mating surface 1131 is configured as the first abutting surface 1132. In this embodiment, the first annular protrusion 1141 can be formed by recessing around the first outer peripheral wall, or by protruding around the first outer peripheral wall. The first annular protrusion 1141 can be integrally formed with the first base 111, or it can be separately set with the first base 111 and then connected by a fixed connection means, such as welding, bonding, or using anchors. The side of the first annular protrusion 1141 facing away from the first mating surface 1131 can be flush with the second end face 1112.

[0027] In another embodiment, the first mating surface 1131 and the first abutting surface 1132 are spaced apart. For example, after the first mating surface 1131 is formed on the first outer peripheral arm, a second annular protrusion is circumferentially surrounding the first outer peripheral wall along the first base 111. The second annular protrusion has a conical surface connected to the first mating surface 1131 and in the shape of a frustum, and a first abutting surface 1132 connected to the conical surface and extending radially outward. The conical surface is arranged to gradually narrow near the first mating surface 1131 and gradually widen near the first abutting surface 1132, so that the conical surface can be used to wedge with the first driving part 12.

[0028] Two first transmission arms 112 are respectively disposed on the first end face 1111, and the two first transmission arms 112 are arranged symmetrically with respect to the center of the first base 111. One end of the first transmission arm 112 is integrally connected to the first base 111 to ensure the strength of the entire first shift fork structure 11, and the other end of the two first transmission arms 112 extends along the first direction toward the side away from the second end face 1112. In order to prevent the first transmission arms 112 from interfering with the first drive part 12, a clearance surface 1121 is formed on the opposite side of the two first transmission arms 112, which is always spaced from the inner wall of the hole structure of the first drive part 12, so that the rotation of the first shift fork structure 11 can proceed smoothly. The clearance surface 1121 may be arc-shaped, and the two clearance surfaces 1121 are on the same circumference to ensure the symmetry of the two first transmission arms 112. The diameter of the clearance surface 1121 is smaller than the minimum inner diameter of the hole structure.

[0029] To better separate the clearance surface 1121 from the hole structure, a stepped surface 1142 is formed on the first end face 1111, located between the clearance surface 1121 and the first mating surface 1131. The first transmission arm 112 extends from the stepped surface 1142 along a first direction, thereby separating the first transmission arm 112 from the first mating surface 1131. The stepped surface 1142 may be arc-shaped, with its inner arc edge on the same circumference as the clearance surface 1121, to facilitate the machining and formation of the stepped surface 1142.

[0030] A second connecting structure is also provided on the two first transmission arms 112 for mounting the second drive unit 14. The second connecting structure enables the second drive unit 14 to rotate radially and output power after operation, thereby achieving dual-axis (i.e., first direction output and second direction output) dual power output in combination with the rotation of the first shift fork structure 11. At the same time, the first drive unit 12 and the second drive unit 14 are highly integrated on the first shift fork structure 11 with a simple structure, which greatly saves installation space compared to using two independent actuators, making the overall structure more compact. It can also achieve the coordinated work of the first drive unit 12 and the second drive unit 14, providing a larger combined torque or power for the same output task, so as to handle a larger load. The alternating use of dual power can also avoid the single power equipment from being in a high load state for a long time to a certain extent, which helps to extend the service life of the overall system and ultimately achieve multi-degree-of-freedom control and better dynamic response.

[0031] In one embodiment, the second connection structure includes first connection surfaces 1151 formed on opposite sides of the two first transmission arms 112, and first connection holes 1152 formed on each of the first connection surfaces 1151. The two first connection surfaces 1151 are symmetrically arranged and have a space between them for the second drive unit 14 to be installed. The second drive unit 14 is radially distributed along its base and its two ends are respectively connected to the two first connection surfaces 1151, so that the first connection surfaces 1151 provide connection support and space arrangement for the second drive unit 14.

[0032] The first connecting hole 1152 can be a threaded hole and can be configured with at least two, such as four. Each of the first connecting holes 1152 is distributed in a circular array to ensure uniform distribution. The second driving part 14 can be fixed by providing through holes or threaded holes adapted to the first connecting holes 1152, and by using a connector such as a screw, the screw is sequentially screwed into the corresponding hole structures on the first connecting hole 1152 and the second driving part 14. In this embodiment, each of the first connecting holes 1152 is arranged in a T-shape in the radial direction, having a wide section and a narrow section. The wide section radially penetrates the avoidance surface 1121 to facilitate the insertion of the screw into the first connecting hole 1152. During installation, the screw is screwed into the narrow section and the second driving part 14, with the screw head located within the wide section. The narrow section radially penetrates the first connecting surface 1151 so that the first connecting hole 1152 passes through the first transmission arm 112, allowing the connector to radially engage with the second driving part 14. In this embodiment, the distribution direction of the two first transmission arms 112 is one of the radial directions of the first base 111, and the radial directions in which the two first transmission arms 112 are distributed are matched as the second direction.

[0033] It should be noted that the second drive unit 14 is equipped with bearing components, ensuring that the corresponding structure of the second drive unit 14 can rotate along the axis of the second direction even when connected to the first connecting surface 1151. Furthermore, when the second drive unit 14 is installed between the two first connecting surfaces 1151, there is a space between the two first transmission arms 112 and the first end face 1111 for the corresponding structure of the second drive unit 14 to rotate and be spaced apart. The side of the first transmission arm 112 furthest from the first base 111 in the first direction is shorter than the second drive unit 14, allowing the rotating portion of the second drive unit 14 to extend out of the space between the two first connecting surfaces 1151. This facilitates the transmission and output of power between the second drive unit 14 and the joint output unit 3.

[0034] In another embodiment, the second connection structure includes a movable block detachably connected to one of the first transmission arms 112, a first connecting surface 1151 formed on the other first transmission arm 112, and a first connecting hole 1152 formed on the first connecting surface 1151. A screw hole is radially formed along the first base 111 on the other first transmission arm 112 where the first connecting surface 1151 is not provided, and the surface of the movable block is provided with an external thread screwed into the screw hole. A protrusion protruding in a second direction is formed on the movable block, and a recess for tenon-and-mortise engagement with the protrusion is provided at the end of the second drive part 14. The recess is rotatably connected to the end of the second drive part 14 via a bearing. The end of the second drive part 14 away from the recess is connected to the first connecting surface 1151 through a connector and the first connecting hole 1152. During installation, after connecting one end of the second drive unit 14 to the first connecting surface 1151, the protrusion is passed through the screw hole and engaged with the concave block in a tenon joint. The movable block is then rotated until it is screwed into the screw hole, thereby achieving the connection between the second drive unit 14 and the first shift fork structure 11.

[0035] Please see Figure 7 and Figure 8 The first drive unit 12 is mounted on the outer periphery of the first shift fork structure 11 and is used to drive the first shift fork structure 11 to rotate around the axis in the first direction. To make the fit between the first drive unit 12 and the first shift fork structure 11 more reasonable, the first drive unit 12 has a connecting side 12a mounted on the first mating surface 1131 and abutting against the first abutting surface 1132, and an enclosing side 12b spaced axially around the outer periphery of the two first transmission arms 112 and the second drive unit 14. The connecting side 12a enables the connection between the first drive unit 12 and the first base 111 of the first shift fork structure 11, and the transmission output of the first drive unit 12 to the first shift fork structure 11 is achieved through the connection between the connecting side 12a and the first connecting structure. The enclosure side 12b allows the entire first drive unit 12 to surround the outer periphery of the first transmission arm 112 and the second drive unit 14. The overall size of the first joint drive unit 1 in the axial direction of the first base 111 is effectively shortened and highly integrated. At the same time, the first drive unit 12 can provide protection for the second drive unit 14 between the first transmission arms 112 to a certain extent, thereby changing the equivalent meshing direction of the first hobbing gear 17 and the joint output unit 3. In conjunction with the second drive unit 14, the first joint drive unit 1 can achieve two-dimensional equivalent driving capability.

[0036] In this embodiment, the first drive unit 12 includes a first rotor 121 mounted on the first mating surface 1131 and abutting against the first abutting surface 1132, a first stator 122 connected to the first housing assembly 13, a first magnetic encoder 123 mounted on the first rotor 121, and a first magnetic ring 124 surrounding the outer periphery of the first rotor 121. When energized, the first rotor 121 and the first stator 122 generate a magnetic field that drives the first rotor 121 to rotate. The first magnetic ring 124 and the first magnetic encoder 123 cooperate with each other. The first magnetic ring 124 provides the first magnetic encoder 123 with information on changes in the magnetic field signal, and the first magnetic encoder 123 provides feedback signals to the controller, thereby forming a complete closed-loop control system to obtain the rotation angle information of the first rotor 121. It should be noted that the structure of the first drive unit 12 is not limited to the structure described in this embodiment. Other power devices capable of driving the first shift fork structure 11 can also be used, such as a rotary cylinder with an output shaft coaxially connected to the first shift fork structure 11.

[0037] In this embodiment, the first rotor 121 has an internal space that is substantially consistent with the horizontal projection of the contour of the first mating surface 1131 along the first direction. The internal space extends through both ends of the first rotor 121 along the first direction, so that the first rotor 121 can be axially fitted onto the first base 111 and fit against the first mating surface 1131. The two ends of the first rotor 121 are divided into a first end and a second end. After the first rotor 121 is fitted onto the first mating surface 1131, the first end is parallel to the first abutting surface 1132 and abuts against the first abutting surface 1132. For this purpose, the first end is configured as the connecting side 12a. The second end is configured as the enclosure side 12b and extends along the first direction toward the side away from the first base 111 after the first rotor 121 is fitted onto the first base 111. The extended second end covers the first transmission arm 112 in its internal space. Due to the presence of the stepped surface 1142, the first transmission arm 112 is spaced apart from the inner wall of the first rotor 121, thereby reducing interference and friction and improving the service life between the first rotor 121 and the first transmission arm 112.

[0038] On the radially outward sidewall of the first rotor 121, i.e., the outer sidewall of the first rotor 121, a first surrounding section 1211, a middle section 1212, and a second surrounding section 1213 are sequentially formed along the axial direction. Both the first surrounding section 1211 and the second surrounding section 1213 are stepped, gradually widening towards the middle section 1212 in a first direction. Both the first surrounding section 1211 and the second surrounding section 1213 have at least two layers of L-shaped stepped platforms that are progressively larger than each other. The at least two layers of stepped platforms are configured so that when other structures are installed on the outer sidewall of the first rotor 121, the corresponding structure is installed on the platform closest to the end, so that the structure is spaced apart from the middle section 1212 by the other stepped platforms. For example, the first surrounding section 1211 has three layers of stepped platforms, and the second surrounding section 1213 has two layers of stepped platforms. The middle section 1212 is located at the point of greatest thickness of the first rotor 121 and is situated axially at the center of the first rotor 121. The first stator 122 surrounds the middle section 1212, allowing the first rotor 121 to magnetically cut against the first stator 122 and generate a magnetic field. The first surrounding section 1211 is positioned close to the first end of the first rotor 121, and the second surrounding section 1213 is positioned close to the second end of the first rotor 121. It should be noted that the first magnetic encoder 123 has through holes through which the wiring of the first stator 122 passes axially.

[0039] To facilitate a reasonable distribution of the first magnetic ring 124, the first magnetic encoder 123, and other structures, the first surrounding section 1211 has three tiers. The first magnetic ring 124 is fixedly fitted onto the tier in the middle of the first surrounding section 1211, so that the first magnetic ring 124 is spaced apart from the middle section 1212. The first magnetic encoder 123 is movably fitted onto the outer periphery of the tier in the middle of the first surrounding section 1211, so that the first magnetic encoder 123 can fit tightly with the first magnetic ring 124.

[0040] Please see Figure 8 and Figure 9 The first housing assembly 13 includes a first housing 131 rotatably mounted on the outer periphery of the first rotor 121, a first rear cover 132 rotatably mounted on the outer periphery of the first rotor 121 and coaxially connected to the first housing 131, and a first spring 133 formed between the first rear cover 132 and the first rotor 121. The first stator 122 is fixedly connected to the first housing 131 so that the first stator 122 and the first housing assembly 13 remain stationary together, thereby allowing the first rotor 121 to rotate relative to the first stator 122 and the first housing assembly 13.

[0041] The first housing 131 can be cylindrical for easy machining, but it is not limited to a cylindrical structure and can be configured in other shapes. The axial direction of the first housing 131 is consistent with the axial direction of the first base 111 and both are arranged along the first direction and are coaxial. One end of the first housing 131 has a first output port 1311 for a portion of the first hobbing gear 17 to extend out. The first output port 1311 can be circular and its diameter is larger than the maximum radial dimension between the two first transmission arms 112, so that the first transmission arms 112 can pass through the first output port 1311, and the first hobbing gear 17 on the second drive part 14 located between the two first transmission arms 112 can pass through the first output port 1311 and exit the first housing 131.

[0042] A first bearing 1312 is provided between the first housing 131 and the first rotor 121 to allow the first rotor 121 to rotate relative to the first housing 131. To facilitate the installation of the first bearing 1312, a first groove 1313 is recessed on the inner wall of the first housing 131 at the position of the outermost step of the second ring section 1213. The groove surface of the first groove 1313 is L-shaped and forms a first installation space adapted to the first bearing 1312 with the corresponding step on the second ring section 1213. The inner ring of the first bearing 1312 is connected and fitted on the second ring section 1213 through the step and is located in the first installation space. The groove wall of the first groove 1313 is fixedly connected to the outer ring of the first bearing 1312, so that the first rotor 121 can rotate relative to the first housing 131. A second groove 1314 is provided on the first housing 131 at the position of the middle section 1212 of the first rotor 121, in which the first stator 122 is fixedly installed. The second groove 1314 is stepped with the first groove 1313 and is deeper than the first groove 1313. This makes the thickness of the first housing 131 corresponding to the first groove 1313 greater than the thickness of the first housing 131 corresponding to the second groove 1314. This makes the installation layers of the first bearing 1312 and the first stator 122 clearly arranged, ensuring the orderly and reasonable arrangement of the rotational engagement of the first housing 131 and the first rotor 121 and the fixed engagement of the first housing 131 and the first stator 122. In terms of spatial layout, the first housing 131, the first stator 122 and the first rotor 121 are reduced and concentrated in both the axial and radial directions, thereby effectively reducing the overall size.

[0043] Since the first housing 131 is currently only connected to the second surrounding section 1213 of the first rotor 121, there is no direct connection between the first surrounding section 1211 of the first rotor 121, i.e., the connection side 12a between the first housing 131 and the first rotor 121. In order to improve the stability between the first housing assembly 13 and the first rotor 121, and at the same time to block the first stator 122, a first rear cover 132 is provided. The first rear cover 132 can also be cylindrical and its outer diameter is consistent with the outer diameter of the first housing 131. A third groove 1321 is recessed on the radially outward side of the first rear cover 132, i.e., on the outer side wall of the first rear cover 132 and near the first housing 131, for the first housing 131 to rest upon. A second groove 1314 of the first housing 131 extends axially away from the first groove 1313, penetrating to the other end of the housing. This ensures that the thickness of the end of the first housing 131 is appropriate enough to be joined with the third groove 1321. The first housing 131 and the first rear cover 132 are then fixedly connected using methods such as welding or anchoring. A first magnetic encoder 123 can be connected to the first rear cover 132 so that the first magnetic encoder 123 can remain stationary relative to the first housing assembly 13. The inner side of the first magnetic encoder 123 is spaced apart from the first rotor 121. A second bearing 1322 is provided between the first rear cover 132 and the first rotor 121 to allow the first rotor 121 to rotate relative to the first rear cover 132. To facilitate the installation of the second bearing 1322, a fourth groove 1323 is recessed on the first rear cover 132. The fourth groove 1323 has at least a first groove surface 13231 for radially connecting to the outer ring of the second bearing 1322 along the first base 111. A stepped platform of the first surrounding section 1211 away from the middle section 1212 along the first direction is connected to the inner ring of the second bearing 1322 so that the first rotor 121 can rotate relative to the first rear cover 132. The first rear cover 132 is connected to the first housing 131 so that the entire first housing assembly 13 and the first and second ends of the first rotor 121 maintain rotational engagement and structural support, and maintain a stable assembly between the first housing assembly 13 and the first drive unit 12.

[0044] To reduce vibration, noise, and uneven prestress generated between the second bearing 1322, the first rear cover 132, and the first rotor 121 during the rotation of the first rotor 121, at least one second groove surface 13232 is provided on the fourth groove 1323, adjacent to the first groove surface 13231 and forming an L-shape with the first groove surface 13231. The second groove surface 13232 is located on the side away from the first housing 131 relative to the first groove surface 13231. The first groove surface 13231 and the second groove surface 13232 are jointly configured as a first wall surface, allowing the second bearing 1322 to be installed along the first direction. The first preload space is formed between the second bearing 1322, the first rotor 121, and the first rear cover 132, and is supported by other stepped platforms on the second end side. Specifically, the first preload space is formed by the first groove surface 13231, the second groove surface 13232, the second bearing 1322, and the first surrounding section 1211 of the first rotor 121. The first spring 133 is axially installed within the first preload space and elastically abuts against the second bearing 1322 and the second groove surface 13232 in the first direction, thereby elastically preloading the first rear cover 132, the second bearing 1322, and the first rotor 121. A stepped surface on the second surrounding section 1213, away from the middle section 1212 in the first direction, is configured as a first mating surface 1131. The first mating surface 1131 is L-shaped and complements the first wall surface, as shown in the figure. ┕ ┑ In this embodiment, during the rotation of the first rotor 121, the elastic preload of the first spring 133 effectively absorbs and attenuates some of the vibration energy generated by the rotor, preventing it from being transmitted outwards. The first spring 133 can change the natural frequency of the system, avoiding resonance with the external structure to a certain extent, thus improving the comfort and precision of the equipment. Furthermore, the elastic preload of the first spring 133 can achieve adaptive spatial adjustment between the second bearing 1322, the first rotor 121, and the first rear cover 132 in the first direction, thereby compensating for and mitigating assembly errors to a certain extent, reducing the off-center load and friction of the second bearing 1322, and making the second bearing 1322 run more smoothly. In this embodiment, the first spring 133 is a first wave spring, which can provide a constant axial preload to the second bearing 1322. At the same time, the first wave spring occupies a small space, providing preload and eliminating axial clearance while occupying only a small space, so as to better achieve the miniaturization of the first joint drive unit 1. It should be noted that the first spring 133 should elastically resist the outer ring of the second bearing 1322.

[0045] Please see Figure 10 and Figure 11The second drive unit 14 includes a first fixed seat 141 with its two ends respectively connected to two first connecting surfaces 1151, a second stator 142 fitted on the first fixed seat 141, a second rotor 143 movably surrounding the second stator 142, a second magnetic encoder 144 mounted on the first transmission arm 112, and a second magnetic ring 145 connected to the first hobbing gear 17. The first hobbing gear 17 is connected to the second rotor 143 and rotatably fitted on the outer periphery of the first fixed seat 141, so that the second drive unit 14 is axially distributed along the second direction according to the arrangement direction of the two first transmission arms 112. In this way, the second drive unit 14 can be installed inside the two first transmission arms 112 and the first drive unit 12, thereby effectively shortening the axial dimension of the entire first joint drive unit 1. In another embodiment, the second drive unit 14 is disposed in the first housing assembly 13. The second drive unit 14 includes a rotary cylinder and a gear connected to the output end 324 of the rotary cylinder. The gear meshes with the first hobbing gear 17 to drive the first hobbing gear 17 to rotate.

[0046] The first fixed base 141 includes a first end plate 1411 connected to one of the first transmission arms 112, a first central shaft 1412 coaxially connected to the first end plate 1411 and having a diameter smaller than the first end plate 1411, and a second end plate 1413 detachably connected to the end of the first central shaft 1412 away from the first end plate 1411 and connected to the other first transmission arm 112. The first end plate 1411 and the second end plate 1413 cooperate with the second connecting structure to achieve connection and fixation with the first shift fork structure 11, while providing installation space for the second stator 142 and the second rotor 143 mounted on the first central shaft 1412, thereby reducing the overall size of the entire second drive unit 14 while ensuring the power output of the first hobbing gear 17. Both the first end plate 1411 and the second end plate 1413 have a structure adapted to the first connecting surface 1151, such as a cylindrical or polygonal prism structure. Both the first end plate 1411 and the second end plate 1413 have threaded grooves that mate with the first connecting hole 1152 for screwing in the connecting parts. To facilitate the sequential mounting of the second stator 142, the second rotor 143, and the first hobbing gear 17 onto the first central shaft 1412, the second end plate 1413 is detachably connected to the end of the first central shaft 1412 furthest from the first end plate 1411. Threaded holes can be provided on both the second end plate 1413 and the first central shaft 1412, allowing the second end plate 1413 to be connected to the first central shaft 1412 using screws or rivets. During assembly, the second stator 142 is fitted onto the first central shaft 1412, and the second rotor 143 is movably arranged around the second stator 142 and can rotate relative to it. The first hobbing gear 17 is fitted onto the second rotor 143.

[0047] To support the second rotor 143 and the first hobbing gear 17, while ensuring the rotation of the first hobbing gear 17 and the second rotor 143, each of the facing sides of the first end plate 1411 and the second end plate 1413 has a first protrusion 146 extending axially along the first fixed seat 141. The first protrusion 146 has a cylindrical structure and its diameter is smaller than the maximum diameter of the first end plate 1411 and the second end plate 1413. The first protrusion 146 is arranged coaxially with the first central axis 1412, so that a fifth annular groove 1461 is formed between the first protrusion 146 and the first end plate 1411, and between the first protrusion 146 and the second end plate 1413. A fifth bearing 147 is fitted in each of the two fifth grooves 1461. The inner ring of the fifth bearing 147 is connected to the groove wall of the fifth groove 1461 to keep it stationary. In one embodiment, the two ends of the second rotor 143 are respectively connected to the outer ring of the fifth bearing 147, and the first hobbing gear 17 is directly fixedly connected to the second rotor 143. In another embodiment, the second rotor 143 is spaced apart from the two second bearings 1322, and the first hobbing gear 17 is connected to the outer ring of the fifth bearing 147. In yet another embodiment, both the first hobbing gear 17 and the second rotor 143 are connected to the outer ring of the fifth bearing 147. Regardless of which embodiment is ultimately used, the first hobbing gear 17 and the second rotor 143 can ultimately rotate relative to the first fixed tooth and the second stator 142 along the axis of the first base 111, i.e., the axis of the first fixed seat 141 along the second direction. It should be noted that the first hobbing gear 17 is spaced apart from the first transmission arm 112 and the first end face 1111 to ensure that the first hobbing gear 17 can rotate. The gaps between the first hobbing gear 17 and the first end face 1111 and between the first hobbing gear 17 and the first transmission arm 112 should be as small as possible to reduce the overall volume, decrease the space ratio, and achieve miniaturization. The second magnetic encoder 144 is mounted on the first transmission arm 112. The wiring of the second magnetic encoder 144 is equipped with a shielding layer (not shown in the figure), or the wiring of the second magnetic encoder 144 is separated from the three-phase wires of the second stator 142 to reduce electromagnetic interference.

[0048] Please see Figure 8 In this embodiment, in order to ensure that the wiring of the second drive unit 14 located between the two first transmission arms 112 is not affected by the rotation of the first shift fork structure 11, the first wiring channel 15 is provided on the first joint drive unit 1, so that after the second drive unit 14 is installed on the first transmission arm 112, the wiring of the second drive unit 14 is arranged on the first shift fork structure 11 through the first wiring channel 15, so that the wiring of the second drive unit 14 can rotate with the first shift fork structure 11.

[0049] The first wiring channel 15 includes a first channel 151 formed within the first fixed base 141 to connect to the second stator 142, and a second channel 152 connecting to the first channel 151 and forming on the first shift fork structure 11. The formation of the first channel 151 causes the wiring of the second drive unit 14 to be distributed along the second direction, so that the wiring of the second drive unit 14 will not be entangled due to the rotation of the corresponding structure of the second drive unit 14. The second channel 152 allows the wiring of the second stator 142 and the wiring of the second magnetic encoder 144 to be laid from the first transmission arm 112 to bypass the space inside the first transmission arm 112, preventing the wiring from affecting the use of the first hobbing gear 17. The second channel 152 also allows the wiring of each second drive unit 14 to converge on the first base 111 for electrical connection with the circuit device.

[0050] The first channel 151 extends axially from the center of the first fixed base 141 through the first central shaft 1412, the first end plate 1411, and the second end plate 1413. A first branch 1511 is radially opened on the first protrusion 146 of the first end plate 141, extending outward through the first fixed base 141. The first branch 1511 connects to the first channel 151 so that the wiring on the second stator 142 enters the main body of the first channel 151 via the first branch 1511 and finally passes through the second channel 152. In this way, when the second rotor 143 and the first hobbing gear 17 rotate, the wiring on the second stator 142 will not be affected at all, ensuring the safe use of the entire first joint drive unit 1.

[0051] The second channel 152 includes a first channel 1521 that connects to the two first transfer arms 112 and the first channel 151, and a second channel 1522 formed in the first base 111 and connected to the first channel 1521. The first channel 1521 includes a first channel 15211 formed on the first transfer arm 112 and located in the middle of the first connecting structure, and a second channel 15212 opened on the first transfer arm 112 and connected to the first channel 15211 and the second channel 1522.

[0052] The first channel 15211 passes through the first transmission arm 112 along the second direction, that is, the first channel 15211 passes through the avoidance surface 1121 and the first connecting surface 1151 of the first transmission arm 112 along the second direction, so that the first channel 15211 connects to the first channel 151, and the wiring of the second stator 142 can pass into the first channel 15211. The first channel 15211 is located at the center of each first connecting hole 1152 and is coaxial with the first channel 151, thereby ensuring the orderly arrangement of the wiring of the second stator 142.

[0053] The second channel 15212 extends outward along the second direction through the clearance surface 1121 of the first transfer arm 112. Specifically, the second channel 15212 is recessed relative to the clearance surface 1121 at its central position and connects to the first channel 15211 and the second runner 1522 along the first direction. This allows the wiring of the second stator 142 to be laid along the second channel 15212 after passing through the first channel 15211 until it enters the second runner 1522. To ensure the basic strength of the first transfer arm 112, the inward-facing side of the second channel 15212 is closed. The outward-opening second channel 15212 facilitates the pulling of wiring manually or mechanically, ensuring proper wiring layout while facilitating wiring laying. It should be noted that the depth of the second channel 15212 should be greater than the overall width or diameter of the line so that the entire line is contained within the second channel 152. When the line is pulled, it should be ensured that the line does not extend outside the second channel 152. This can be achieved by straightening the line or by filling the second channel 152 with glue and allowing it to solidify before putting it into use.

[0054] In one embodiment, a first channel 1521 is provided on one of the first transmission arms 112, meaning that only one first transmission arm 112 has a first channel 15211 and a second channel 15212. In another embodiment, the first channel 15211 and the second channel 15212 are symmetrically distributed on both first transmission arms 112, so that the wiring can be laid in two bundles, further ensuring that the wiring does not extend beyond the first channel 1521. A first mounting groove 15213 is provided on one of the first transmission arms 112, intersecting and communicating with the second channel 15212. The shape and size of the first mounting groove 15213 are adapted to the size of the second magnetic encoder 144, so that the second magnetic encoder 144 can be completely embedded in the first mounting groove 15213. The first mounting groove 15213 has a connecting hole extending inward along the second direction to pass through the first connecting surface 1151, thereby enabling the second magnetic encoder 144 to perform real-time closed-loop control of the operation of the second drive unit 14 and detect the real-time speed of the second rotor 143. The first mounting groove 15213 may be opened only on the selected first transmission arm 112, or it may be opened on both the first transmission arm 112 and the first base 111. The specific opening position is determined according to factors such as the size of the second drive unit 14.

[0055] The second channel 1522 includes a third channel 15221 that connects the two second channels 15212 respectively, and a channel opening 15222 located at the center of the first base 111 and extending through the first base 111 in a first direction. The third channel 15221 is radially opened along the first base 111 and preferably extends through the first outer peripheral wall of the first base 111, so as to facilitate the insertion of the line from the second channel 15212 into the third channel 15221 from outside the first base 111. The third channel 15221 extends through the first outer peripheral wall, and the third channel 15221 may also partially extend through the first annular protrusion 1141 to provide sufficient space for the third channel 15221, and also to facilitate the laying of the line. In this embodiment, the third channel 15221 penetrates one end of the first outer peripheral wall and extends along the first direction through the second channel 15212 and the first mounting groove 15213, thereby ensuring that the wiring of the second drive unit 14 can continue to pass through the second channel 15212 and the first mounting groove 15213 into the third channel 15221. The channel opening 15222 is located at the center of the first base 111 and its diameter or radial dimension is larger than that of the third channel 15221, so that the channel opening 15222 has sufficient space for the wiring in the two first channels 151 to converge therein. The converged wiring exits through the channel opening 15222 along the first direction. The second magnetic ring 145 is fixedly fitted on the end of the first hobbing gear 17 near the first mounting groove 15213 and is used in conjunction with the second magnetic encoder 144 through the connecting hole.

[0056] The first conductive slip ring 16 is coaxial with and connected to the first rear cover 132. Multiple screw holes are correspondingly formed on both the first conductive slip ring 16 and the first rear cover 132, and screws are used to connect them. The outer diameter of the first conductive slip ring 16 is consistent with the outer diameter of the first housing 131 and the first rear cover 132 to ensure the integrity of the first joint drive unit 1. After the wires in the first wiring channel 15 exit through the channel opening 15222, the wires pass through the rotating part at the center of the first conductive slip ring 16 to avoid wire tangling.

[0057] Please see Figure 11 and Figure 12The first hobbing gear 17 has a cylindrical structure and its axial dimension is smaller than that of the first fixed base 141. The interior of the first hobbing gear 17 is axially connected to form a space for the second rotor 143 to pass through. The first hobbing gear 17 is fitted onto the second rotor 143 and is axially arranged in the second direction. The second hobbing gear 27 is connected to the outer ring of the fifth bearing 147. On the outer side wall of the first hobbing gear 17, there are first strip teeth 171 distributed circumferentially along the first hobbing gear 17 for meshing and coupling power output, and first annular teeth 172 formed on one side of the outer side wall of the first hobbing gear 17 for sliding output engagement. The first strip teeth 171 are distributed sequentially along the circumference of the first hobbing gear 17, and a first conventional tooth groove is formed between two adjacent first strip teeth 171. When the first hobbing gear 17 rotates in the second direction (i.e., the circumferential direction of the first hobbing gear 17 itself), the first strip teeth 171 can drive the gear structure of the joint output unit 3 to rotate in the second direction through the first conventional tooth groove to achieve meshing engagement. When the first hobbing gear 17 rotates along the axis of the first direction (i.e., the circumferential direction of the first base 111), the first strip tooth 171 can drive the matching gear structure with the same function to rotate along the second direction to achieve coupling. The first hobbing gear 17 can achieve dual-axis rotation in the first and second directions by rotating alternately or simultaneously along the circumferential direction of the first base 111 and its own circumferential direction. The integration and state switching of two transmission modes are realized through one first hobbing gear 17, which greatly simplifies the mechanical structure, reduces the number of parts, and is one of the key factors in realizing the miniaturization of the entire first joint drive unit 1. It also improves the redundancy and reliability of the system and achieves lightweighting.

[0058] The first annular tooth 172 includes, from the inside out, a first tooth protrusion 1721 and a first annular tooth 1722 surrounding the outer periphery of the first tooth protrusion 1721. The first annular tooth 1722 can be configured as multiple rings, and the first strip tooth 171 adjacent to the first annular tooth 172 gradually curves from straight to arc. Specifically, the first annular tooth 1722 includes a plurality of first continuous annular teeth 17221 that are annular and continuous, and a plurality of first discontinuous annular teeth 17222 that are symmetrically distributed on both sides of the outer periphery of each first continuous annular tooth 17221. A first arc-shaped tooth groove is formed between adjacent first tooth protrusions 1721 and first continuous annular teeth 17221, between two adjacent first continuous annular teeth 17221, between adjacent first continuous annular teeth 17221 and first discontinuous annular teeth 17222, and between two adjacent first discontinuous annular teeth 17222, so that the first annular tooth 172 can mesh with other gear structures. Multiple consecutive first continuous ring teeth 17221 form continuous first arc-shaped tooth grooves on the outer periphery of the first tooth protrusion 1721. First discontinuous tooth grooves form discontinuous first arc-shaped tooth grooves with open ends on the outer periphery of the first tooth protrusion 1721 and the first continuous ring teeth 17221. When the first ring tooth 172 meshes with other gear structures with the same structure, the operation of the first drive unit 12 will drive the first hob 17 to rotate around a first direction. At this time, the first ring tooth 172 slides with the same gear structure without interfering with it. This can be used to adjust the position of the first hob 17 relative to other gear structures. When the second drive unit 14 operates, the first ring tooth 172 can achieve the same function as the first strip tooth 171 and mesh with other gear structures to drive them to rotate around a second direction. Thus, even with only one first hob 17, it can be used for multi-axis rotation output, achieving multi-degree-of-freedom power output while ensuring a smaller number of parts.

[0059] During assembly of the first joint drive unit 1 of the present invention, the fifth bearings 147 on the two first end plates 1411 are first installed, and then the second stator 142, the second rotor 143, and the first hobbing gear 17 are installed in place. Next, the second drive unit 14 and the first hobbing gear 17 are placed between the two first connecting surfaces 1151. After the second drive unit 14 is fixed to the first transmission arm 112 via the first connecting hole 1152 using a connector, the first channel 151 and the second channel 152 allow the wiring of the second drive unit 14 to be laid out and converge into the first conductive slip ring 16. Then, the first rotor 121 is fitted onto the first mating surface 1131 along the first direction. The first abutting surface 1132 restricts the fitting degree of the first rotor 121. A magnetic ring 124 and a second bearing 1322 are sequentially fitted onto the first surrounding section 1211. The first bearing 1312 and the first stator 122 are then installed in the first groove 1313 and the second groove 1314. After the first magnetic encoder 123, the first rear cover 132, and the first conductive slip ring 16 are sequentially installed, the first housing 131 and the first rear cover 132 are finally connected and fixed, so that the wiring of the second drive unit 14 passes through the first conductive slip ring 16. The wiring of the first drive unit 12 passes through the through hole on the first magnetic encoder 123, the hole structure opened on the first rear cover 132 and the first conductive slip ring 16, so that the second drive unit 14 and the first housing assembly 13 surround the first transmission arm 112, thus completing the integrated installation of the first joint drive unit 1.

[0060] Please see Figures 14 to 16The second joint drive unit 2 is arranged along a third direction, meaning its overall axial direction is distributed along the third direction. The second joint drive unit 2 includes a second shift fork structure 21, a third drive section 22 connected to the second shift fork structure 21 and used to drive the second shift fork structure 21 to rotate around a third direction, a second housing assembly 23 fitted onto the third drive section 22 and the second shift fork structure 21, a fourth drive section 24 connected to the second shift fork structure 21, a second wiring channel 25 formed on the second shift fork structure 21, a second conductive slip ring 26 connected to the second housing assembly 23, and a second hobbing gear 27 connected to the second shift fork structure 21. The second shift fork structure 21 provides connection support for the installation of the third drive section 22 and the fourth drive section 24, and highly integrates the third drive section 22 and the fourth drive section 24. The second housing assembly 23 provides protective support for the entire second joint drive unit 2 and is used to cooperate with the third drive section 22 to position the second shift fork structure 21 and the third drive section 22, fixing them within the second housing assembly 23. The second hob 27 is used for rotation to output power. The third drive unit 22 and the fourth drive unit 24 enable the second hob 27 to output power in both the third and fourth directions, thus achieving a combination of dual power output from the second hob 27. This lays the foundation for the subsequent superposition of two joint drive units to form a three-degree-of-freedom system, reducing costs and complexity to a certain extent and making the entire second joint drive unit 2 simpler. It achieves multi-degree-of-freedom output within a smaller volume, optimizing space utilization. It ensures that the third and fourth direction rotations of the second hob 27 are independent, preventing power output interference and enabling precise control of the second shift fork structure 21 and the second hob 27. This allows for reliable output as needed, improving motion control accuracy. The simplified structure also reduces mechanical wear and maintenance costs. The second wiring channel 25 provides a rational layout for the wiring of the internal fourth drive unit 24, ensuring that all components operate as expected. The second conductive slip ring 26 works in conjunction with the second wiring channel 25 to achieve a rational wiring layout.

[0061] Please see Figures 17 to 20 The second shift fork structure 21 includes a second base 211 and two second transmission arms 212 connected to the second base 211 and spaced apart along the fourth direction. The second base 211 provides support for the third drive unit 22 and the second transmission arms 212. The second transmission arms 212 cooperate with the second base 211 to realize the integrated arrangement of the third drive unit 22 and the fourth drive unit 24.

[0062] The second base 211 can be configured as a block-shaped three-dimensional structure. In this embodiment, the first base 111 can be configured as a cylinder. In another embodiment, the second base 211 can also be configured as a cuboid or other geometric structure, but a relatively regular geometric shape such as a polygonal prism should be selected to facilitate batch processing and make the installation between the second base 211 and the first drive unit 12 easier. The center of the second base 211 is selected as a reference to give it an axial direction and a radial direction perpendicular to the axial direction. The second base 211 is axially configured as a third direction, and the direction corresponding to the second base 211 around the axis of the third direction is defined as the circumferential direction of the second base 211. The first base 111 has a third end face 2111 and a fourth end face 2112 relatively distributed along the third direction. The second base 211 also has a second outer peripheral wall distributed around the first base 111 in the circumferential direction of the second base 211.

[0063] The second base 211 has a third connecting structure for the third drive unit 22 to cooperate with. The third connecting structure, through its connection with the third drive unit 22, can drive the second base 211 to rotate around a third direction and output power, thereby realizing the installation of the third drive unit 22 and the drive of the third drive unit 22 on the second base 211. The third connecting structure has a second mating surface 2131 and a second abutting surface 2132 formed on the second base 211. The third drive unit 22 is fitted onto the second mating surface 2131 along the third direction to be installed on the second base 211, and after being installed on the second base 211, the third drive unit 22 abuts against the second abutting surface 2132 along the third direction to position the installation position of the third drive unit 22 and ensure that the third drive unit 22 can be installed in place.

[0064] In this embodiment, the third connecting structure includes an extension shaft 213 extending from the fourth end face 2112 along a third direction, and a third driving part 22 coaxially mounted on the extension shaft 213. Specifically, the outer peripheral wall of the extension shaft 213 is configured as a second mating surface 2131, and the third driving part 22 is fitted and connected to the second mating surface 2131 and sleeved on the extension shaft 213. The entire extension shaft 213 can be cylindrical for ease of installation, and a third surrounding segment 213a close to the second base 211 and a fourth surrounding segment 213b away from the second base 211 are respectively provided on both ends of the extension shaft 213. The third surrounding segment 213a is integrally connected to the fourth end face 2112, and the third surrounding segment 213a is arranged in a stepped shape with at least two third annular protrusions 2133 of gradually increasing diameter on the side facing the fourth end face 2112. The second abutting surface 2132 is formed on the third surrounding segment 213a and located on the third annular protrusion 2133 close to the fourth surrounding segment 213b along a third direction. When the third driving part 22 is fitted onto the extension shaft 213, the third driving part 22 abuts against the second abutting surface 2132 on the side facing the second base 211 along a third direction. The fourth surrounding segment 213b is also stepped and has at least two fourth annular protrusions 2134 of gradually narrowing diameter on the side facing away from the fourth end face 2112, so that the third driving part 22 can be fitted onto the extension shaft 213 from the fourth surrounding segment 213b along a third direction. In this embodiment, the third connection structure can be applied to usage scenarios where the installation space in the radial dimension of the second base 211 is limited.

[0065] In this embodiment, the second abutting surface 2132 and the second mating surface 2131 form a certain angle. The specific setting is similar to or the same as the setting of the first abutting surface 1132 and the first mating surface 1131, and will not be described in detail here.

[0066] Two second transmission arms 212 are each disposed on the third end face 2111, and the two second transmission arms 212 are arranged symmetrically with respect to the second base 211. One end of the second transmission arm 212 is integrally connected to the second base 211 to ensure the strength of the entire second shift fork structure 21. The other end of the two second transmission arms 212 extends along the third direction toward the side away from the fourth end face 2112. The opposite side of the two second transmission arms 212 is configured as the back surface 2121. The back surface 2121 of the two second transmission arms 212 and the second outer peripheral wall are on the same circumference to ensure precise control of the radial dimension of the entire second shift fork structure 21, while ensuring the strength of the second transmission arms 212 and reducing the processing difficulty of the second shift fork structure 21 to a certain extent.

[0067] A fourth connection structure is also provided on the two second transmission arms 212 for the fourth drive unit 24 to be installed between the two second transmission arms 212. The fourth connection structure enables the fourth drive unit 24 to rotate around the fourth direction to output power after operation, thereby achieving dual-axis (i.e., third-direction output and fourth-direction output) dual-power output in combination with the rotation of the second shift fork structure 21. At the same time, the third drive unit 22 and the fourth drive unit 24 are installed and integrated on the second shift fork structure 21 with a simple structure, which greatly saves installation space compared with the use of two independent actuators, making the overall structure more compact. It can also realize the coordinated work of the third drive unit 22 and the fourth drive unit 24, providing a larger combined torque or power for the same output task, so as to handle a larger load. The alternating use of dual power can also avoid the single power equipment from being in a high-load state for a long time to a certain extent, which helps to extend the service life of the overall system, and ultimately achieve multi-degree-of-freedom control and better dynamic response.

[0068] In one embodiment, the fourth connection structure includes second connection surfaces 2141 formed on opposite sides of the two second transmission arms 212, and second connection holes 2142 formed on each second connection surface 2141. The arrangement of the second connection surfaces 2141 is consistent with that of the first connection surface 1151, and the arrangement of the second connection holes 2142 is consistent with that of the first connection holes 1152, so that the second connection surfaces 2141 also have multiple second connection holes 2142. Each second connection hole 2142 is consistent with the first connection hole 1152, having a wide section and a narrow section. A connector is used to connect the second connection holes 2142 to the fourth drive unit 24. Therefore, the specific structure of the second connection surfaces 2141 and the second connection holes 2142 will not be described in detail, and the structure of the first connection surfaces 1151 and the first connection holes 1152 can be referred to.

[0069] Please see Figure 18 The third drive unit 22 is mounted on the outer periphery of the extension shaft 213 (i.e., the second mating surface 2131) and is used to drive the second shift fork structure 21 to rotate around the third directional axis. In this embodiment, the third drive unit 22 includes a third rotor 221 mounted on the second mating surface 2131 and abutting against the second abutting surface 2132, a third stator 222 connected to the second housing assembly 23, a third magnetic encoder 223 mounted on the third rotor 221 or the extension shaft 213, and a third magnetic ring 224 surrounding the outer periphery of the third rotor 221 or the extension shaft 213. After being energized, the third rotor 221 and the third stator 222 generate a magnetic field that drives the third rotor 221 to rotate. The third magnetic ring 224 and the third magnetic encoder 223 cooperate to provide feedback signals to the controller to form a complete closed-loop control system.

[0070] In this embodiment, the third rotor 221 also has an internal space that is substantially consistent with the horizontal projection of the contour of the second mating surface 2131 along the third direction. This internal space extends through both ends of the third rotor 221 along the third direction, allowing the third rotor 221 to be mounted on the extension shaft 213 of the second base 211 along the third direction and to fit against the second mating surface 2131. To shorten the overall size of the second joint drive unit 2 radially in the second base 211, making the second joint drive unit 2 more suitable for installation environments with limited radial dimensions, the third rotor 221 and the third stator 222 maintain substantially consistent dimensions in the third direction, and the radial thickness of the third rotor 221 is minimized as much as possible. The second magnetic ring 145 and the second magnetic encoder 144 are both mounted on the fourth surrounding section 213b. To facilitate the rational distribution of the second magnetic ring 145, the second magnetic encoder 144, and other structures, at least two fourth annular protrusions 2134 are formed on the fourth surrounding section 213b. Both the second magnetic ring 145 and the second magnetic encoder 144 are fitted onto the fourth annular protrusions 2134 near the third surrounding section 213a, allowing them to be closer to the third rotor 221 for monitoring. The third magnetic ring 224 is fixedly fitted onto the fourth surrounding section 213b, while the second magnetic encoder 144 is spaced apart on the fourth surrounding section 213b and does not rotate with the second shift fork structure 21. It should be noted that the second magnetic encoder 144 has through holes for the lines of the third stator 222 to pass through it in a third direction.

[0071] Please see Figure 15 The second housing assembly 23 includes a second housing 231 rotatably mounted on the outer periphery of the second shift fork structure 21, a second rear cover 232 rotatably mounted on the outer periphery of the second shift fork structure 21 and coaxially connected to the second housing 231, and a second spring 233 formed between the second rear cover 232 and the second shift fork structure 21. The third stator 222 is fixedly connected inside the second housing 231 so that the third stator 222 and the second housing assembly 23 remain stationary together, thereby allowing the third rotor 221 to rotate with the second shift fork structure 21 relative to the third stator 222 and the second housing assembly 23.

[0072] The second housing 231 can be cylindrical for easy machining, but it is not limited to a cylindrical structure and can be configured in other shapes. The axial direction of the second housing 231 is consistent with the axial direction of the second base 211 and they are coaxially distributed along a third direction. One end of the second housing 231 has a second output port 2311 for a portion of the second hobbing gear 27 to extend out. The shape of the second output port 2311 can be circular and its diameter is larger than the maximum radial dimension between the two second transmission arms 212, so that the second transmission arms 212 can pass through the second output port 2311, and the second hobbing gear 27 on the fourth drive part 24 located between the two second transmission arms 212 can pass through the second output port 2311 and exit the second housing 231.

[0073] To ensure a reasonable design and effectively reduce the radial dimension of the entire second joint drive unit 2, the second housing 231 includes, along a third direction, a first housing segment 231a, a second housing segment 231b, and a third housing segment 231c. The first housing segment 231a surrounds the outer periphery of the two second transmission arms 212 to protect the second transmission arms 212 and the internal fourth drive unit 24, while also providing a connection point between the second joint drive unit 2 and the joint output unit 3. The second housing segment 231b surrounds the outer periphery of the extension shaft 213 and the third drive unit 22 to provide mounting connection points and protection for the third stator 222 and the third magnetic encoder 223. The third housing segment 231c provides a connection point for mounting with the second rear cover 232. The multi-section design of the second housing 231, combined with the extension shaft 213, elongates the entire second joint drive unit 2 in the third direction, i.e., the overall axial direction of the second joint drive unit 2. This allows the third drive unit 22 and the fourth drive unit 24 to achieve dual power output of the second hob 27 through the second shift fork structure 21, while also being used in installation environments with limited radial space.

[0074] To increase the stability between the second housing 231 and the second shift fork structure 21, a third bearing 2315 is provided between the second housing 231 and the extension shaft 213 to allow the extension shaft 213 to rotate relative to the second housing 231. At least one second annular protrusion on the third surrounding section 213a is adapted to the inner ring of the third bearing 2315. In order to enable the third bearing 2315 to be used better, three third annular protrusions 2133 are provided on the third surrounding section 213a, and the third bearing 2315 is mounted on the third annular protrusion 2133 located in the middle, so that the third bearing 2315 is spaced apart from the fourth end face 2112 and the third stator 222 along the third direction. A sixth groove 2312 is recessed on the inner wall of the second shell section 231b at a position corresponding to the third annular section 213a. The groove surface of the sixth groove 2312 is L-shaped and surrounds the third annular protrusion 2133 on the third annular section 213a to form a second mounting space adapted to the third bearing 2315. The inner ring of the third bearing 2315 is connected and fitted on the second annular protrusion and located in the second mounting space. The groove wall of the sixth groove 2312 is fixedly connected to the outer ring of the third bearing 2315, so that the extension shaft 213 can rotate relative to the second shell 231.

[0075] To reduce the radial dimension of the second housing segment 231b to some extent, an inner extension edge 2313 is formed on the inner wall of the second housing segment 231b near the first housing segment 231a. The inner extension edge 2313 extends towards the first housing segment 231a and then bends radially inward along the second housing segment 231b, forming an L-shape. The sixth groove 2312 is formed on the L-shaped inner extension edge 2313 to provide installation space for the third bearing 2315. At the same time, the inner extension edge 2313 can also block the third bearing 2315 in a third-order direction, preventing the third bearing 2315 from approaching the fourth end face 2112. It should be noted that the inner extension edge 2313 must not contact the inner ring of the third bearing 2315 but only connect to the outer ring of the third bearing 2315. Correspondingly, the third annular protrusion 2133 closest to the fourth end face 2112 among the three third annular protrusions 2133 is directly opposite the inner extension edge 2313, and the third annular protrusion 2133 provides space for the existence of the inner extension edge 2313.

[0076] The third housing segment 231c is positioned away from the first housing segment 131 and has a narrow side adapted to the dimensions of the second housing segment 231b and a wide side that gradually widens towards the end away from the narrow side and the first housing segment 231a. A seventh groove 2314 is recessed on the narrow side relative to the inner wall of the second housing segment 231b. The seventh groove 2314 has a third groove surface and a fourth groove surface forming an L-shape. The third groove surface is arranged radially parallel to the second housing segment 231. The second magnetic encoder 144 is connected and abuts against the third groove surface and is internally spaced from the extension shaft 213. The fourth groove surface is arranged radially parallel to the third groove surface.

[0077] Since the second housing 231 is currently only connected to the third surrounding section 213a of the extension shaft 213, a second rear cover 232 is provided to improve the stability between the second housing assembly 23 and the extension shaft 213, and to block the third stator 222. The second rear cover 232 can also be cylindrical and its outer diameter can be consistent with the outer diameter of the wide side of the third housing section 231c. Both the second magnetic encoder 144 and the second rear cover 232 can be connected to the third housing section 231c by means of screws or the like. To further improve the robustness between the second rear cover 232 and the second housing 231, a first inner extension ring 2321 protrudes from the second rear cover 232 along a third direction toward the second housing 231. The first inner extension ring 2321 passes into the seventh groove 2314 and abuts against the fourth groove surface.

[0078] A fourth bearing 2322 is provided between the second rear cover 232 and the fourth surrounding section 213b of the extension shaft 213, which allows the second shift fork structure 21 to rotate relative to the second rear cover 232. To facilitate the installation of the fourth bearing 2322, an eighth groove 2323 is recessed on the second rear cover 232. The eighth groove 2323 has at least a second wall surface for radial connection to the outer ring of the fourth bearing 2322 along the second base 211. A third annular protrusion 2133 of the fourth surrounding section 213b, which is located away from the second base 211 in a third direction, is connected to the inner ring of the fourth bearing 2322, so that the extension shaft 213 can rotate relative to the second rear cover 232. The second rear cover 232 is connected to the second housing 231 so that the entire second housing assembly 23 and the second shift fork structure 21 maintain rotational engagement and structural support, and maintain a stable assembly between the second housing assembly 23 and the third drive unit 22. The surface of the fourth annular protrusion 2134, to which the fourth bearing 2322 is connected, is fitted as a second mating surface 2131. The second mating surface 2131 is L-shaped and, together with the second wall surface, forms a space in which the fourth bearing 2322 is installed. A second inner ring 2324 can be formed protruding from the second rear cover 232. The second inner ring 2324 is disposed through the first shell section 231a in a third direction, and the eighth groove 2323 is formed on the second inner ring 2324.

[0079] To reduce vibration, noise, and uneven prestress generated between the fourth bearing 2322, the second rear cover 232, and the extension shaft 213 during the rotation of the third rotor 221 and the extension shaft 213, an L-shaped fifth and sixth groove surface are provided on the eighth groove body 2323. The fifth groove surface is arranged parallel to the third direction, and the sixth groove surface is arranged radially parallel to the second rear cover 232. The fifth and sixth groove surfaces are jointly configured as the second wall surface, allowing the fourth bearing 2322 to be installed along the third direction towards the fourth end face 211. 2. One side abuts against the second mating surface 2131. A second pre-tightening space is provided between the fourth bearing 2322, the extension shaft 213 and the second rear cover 232. That is, the second pre-tightening space is formed by the fifth groove surface, the sixth groove surface, the fourth bearing 2322 and the second mating surface 2131. The second spring 233 is installed in the second pre-tightening space along the third direction and elastically abuts against the fourth bearing 2322 and the sixth groove surface along the third direction, thereby elastically pre-tightening the second rear cover 232, the fourth bearing 2322 and the extension shaft 213. During the rotation of the third rotor 221 and the second shift fork structure 21, the elastic preload of the second spring 233 can effectively absorb and attenuate some of the vibration energy generated by the third rotor 221 and the extension shaft 213, preventing it from being transmitted outward. The second spring 233 can change the natural frequency of the system, avoiding resonance with the external structure to a certain extent, thus improving the comfort and precision of the equipment. Furthermore, the elastic preload of the second spring 233 can achieve adaptive spatial adjustment between the fourth bearing 2322, the extension shaft 213, and the second rear cover 232 in the third direction, thereby compensating for and mitigating assembly errors to a certain extent, reducing the off-center load and friction of the fourth bearing 2322, and making the fourth bearing 2322 run more smoothly. In this embodiment, the second spring 233 is a second wave spring, which provides a constant axial preload to the fourth bearing 2322. Simultaneously, the second wave spring occupies a small spatial proportion, providing preload and eliminating axial backlash while occupying minimal space, thus better enabling the miniaturization of the second joint drive unit 2. This allows for the application of elastic preload to the bearing or related mating surfaces to suppress axial (third-direction) movement within the assembly clearance and improve meshing stability. It should be noted that the second spring 233 should elastically abut against the outer ring of the fourth bearing 2322.

[0080] Please see Figure 19 and Figure 20The fourth drive unit 24 includes a second fixed seat 241 with its two ends respectively connected to two second connecting surfaces 2141, a fourth stator 242 fitted on the second fixed seat 241, a fourth rotor 243 movably surrounding the fourth stator 242, a fourth magnetic encoder 244 mounted on the second transmission arm 212, and a fourth magnetic ring 245 connected to the second hobbing gear 27. The second hobbing gear 27 is connected to the fourth rotor 243 and rotatably fitted on the outer periphery of the second fixed seat 241, so that the fourth drive unit 24 is axially distributed along the fourth direction according to the arrangement direction of the two second transmission arms 212, thus allowing the fourth drive unit 24 to be installed inside the two second transmission arms 212. In another embodiment, the fourth drive unit 24 is disposed in the second housing assembly 23. The fourth drive unit 24 includes a rotary cylinder and a gear connected to the output end 324 of the rotary cylinder. The gear meshes with the second hobbing gear 27 to drive the second hobbing gear 27 to rotate.

[0081] The second fixed base 241 includes a third end plate 2411 connected to one of the second transmission arms 212, a second central shaft 2412 coaxially connected to the third end plate 2411 and having a smaller diameter than the third end plate 2411, and a fourth end plate 2413 detachably connected to the end of the second central shaft 2412 away from the third end plate 2411 and connected to the other second transmission arm 212. The third end plate 2411 and the fourth end plate 2413 cooperate with the fourth connecting structure to achieve connection and fixation to the second shift fork structure 21, while providing installation space for the fourth stator 242 and the fourth rotor 243 mounted on the second central shaft 2412, thereby reducing the overall size of the entire fourth drive unit 24 while ensuring the power output of the first hobbing gear 17. All structures of the second fixed base 241 are identical to those of the first fixed base 141. The connection between the second fixed base 241 and the fourth connecting structure is similar to the connection between the first fixed base 141 and the second connecting structure, and will not be described in detail here. The second hobbing gear 27 is fitted onto the fourth rotor 243.

[0082] To support the fourth rotor 243 and the second hobbing gear 27, while ensuring the rotation of both the second hobbing gear 27 and the fourth rotor 243, a second protrusion 2414 extending axially along the second fixed seat 241 is provided on the opposing side of the third end plate 2411 and the fourth end plate 2413. The second protrusion 2414 has a cylindrical structure and a diameter smaller than the maximum diameter of the third end plate 2411 and the fourth end plate 2413. The second protrusion 2414 is coaxially arranged with the second central axis 2412, so that a ring-shaped ninth groove 2415 is formed between the second protrusion 2414 and the third end plate 2411, and between the second protrusion 2414 and the fourth end plate 2413. A sixth bearing 2416 is fitted inside each of the two ninth grooves 2415. The inner ring of the sixth bearing 2416 is connected to the groove wall of the ninth groove 2415 to maintain its stationary position. The connection and fit between the second hobbing gear 27, the fourth rotor 243 and the sixth bearing 2416 are similar to the connection and fit between the first hobbing gear 17, the second rotor 143 and the fifth bearing 147, and will not be described in detail here.

[0083] Please see Figure 18 and Figure 20 In this embodiment, in order to ensure that the wiring of the fourth drive unit 24 located between the two second transmission arms 212 is not affected by the rotation of the second shift fork structure 21, a second wiring channel 25 is provided on the second joint drive unit 2, so that after the fourth drive unit 24 is installed on the second transmission arm 212, the wiring of the fourth drive unit 24 is arranged on the second shift fork structure 21 through the second wiring channel 25, so that the wiring of the fourth drive unit 24 can rotate with the second shift fork structure 21.

[0084] The second wiring channel 25 includes a third channel 251 formed within the second fixed base 241 to connect to the fourth stator 242, and a fourth channel 252 connecting the third channel 251 and forming on the second shift fork structure 21. The formation of the third channel 251 causes the wiring of the fourth drive unit 24 to be distributed along the fourth direction, so that the wiring of the fourth drive unit 24 will not be entangled due to the rotation of the corresponding structure of the fourth drive unit 24. The fourth channel 252 allows the wiring of the fourth stator 242 and the wiring of the fourth magnetic encoder 244 to be laid from the second transmission arm 212 to bypass the space inside the second transmission arm 212, preventing the wiring from affecting the use of the second hobbing gear 27. The fourth channel 252 also allows the wiring of each fourth drive unit 24 to converge on the second base 211 and finally pass through the extension shaft 213 and the rotating part inside the second conductive slip ring 26 to be electrically connected to the circuit device.

[0085] The third channel 251 extends axially from the center of the second fixed base 241 through the second central shaft 2412, the third end plate 2411, and the fourth end plate 2413. A second branch 2511 is radially opened on the second protrusion 2414 of the third end plate 241, extending outward through the second fixed base 241. The second branch 2511 connects to the third channel 251 so that the wiring on the second stator 142 enters the main body of the third channel 251 via the second branch 2511 and finally passes through the fourth channel 252. In this way, when the fourth rotor 243 and the second hobbing gear 27 rotate, the wiring on the fourth stator 242 will not be affected at all, ensuring the safe use of the entire second joint drive unit 2.

[0086] The fourth channel 252 includes a third channel 2521 that connects to the two second transfer arms 212 and the third channel 251, and a fourth channel 2522 formed in the second base 211 and connected to the third channel 2521. The third channel 2521 includes a fourth secondary channel 25211 formed on the second transfer arm 212 and located in the middle of the fourth connection structure, and a fifth secondary channel 25212 opened on the second transfer arm 212 and connected to the fourth secondary channel 25211 and the fourth channel 2522.

[0087] The fourth channel 25211 extends through the second transfer arm 212 along the fourth direction, specifically extending through the back surface 2121 and the second connecting surface 2141 of the second transfer arm 212 along the fourth direction. The fifth channel 25212 extends outward along the fourth direction through the back surface 2121 of the second transfer arm 212. The configuration of the fourth channel 25211 is the same as that of the first channel 15211, and the configuration of the fifth channel 25212 is the same as that of the second channel 15212; therefore, it will not be described in detail here.

[0088] A second mounting groove 25213 is formed on one of the second transmission arms 212, intersecting and communicating with the fifth channel 25212. The shape and size of the second mounting groove 25213 are adapted to the size of the fourth magnetic encoder 244, so that the fourth magnetic encoder 244 can be completely embedded in the second mounting groove 25213. The arrangement of the second mounting groove 25213 and the fourth magnetic encoder 244 is similar to that of the first mounting groove 15213 and the second magnetic encoder 144, and will not be described in detail here.

[0089] The fourth channel 2522 includes a sixth channel 25221 that connects the two fifth channels 25212 respectively, and a seventh channel 25222 located at the center of the second base 211 and extending through the second base 211 and the extension axis 213 in a third direction. The sixth channel 25221 is radially opened along the second base 211 and preferably penetrates the second outer peripheral wall of the second base 211, so as to facilitate the routing of the line from outside the second base 211 from inside the fifth channel 25212 into the sixth channel 25221 and the seventh channel 25222. The sixth channel 25221 penetrating the second outer peripheral wall makes the routing work easier. In this embodiment, the sixth channel 25221 extends through one end of the second outer peripheral wall and then extends along a third direction through the fifth channel 25212 and the second mounting groove 25213, thereby ensuring that the wiring of the fourth drive unit 24 can continue to pass through the sixth channel 25221 from the fifth channel 25212 and the second mounting groove 25213. The fourth magnetic ring 245 is fixedly fitted on the end of the second hobbing gear 27 near the second mounting groove 25213 and is used in conjunction with the fourth magnetic encoder 244 through a connecting hole.

[0090] The second conductive slip ring 26 is coaxial with and connected to the second rear cover 232. Multiple screw holes are correspondingly formed on the second conductive slip ring 26 and the second rear cover 232, and screws are used to connect them by screwing them into these holes. The outer diameter of the second conductive slip ring 26 is consistent with the outer diameter of the second housing 231 and the second rear cover 232 to ensure the integrity of the second joint drive unit 2. After the wires in the second wiring channel 25 pass through the seventh channel 25222, the wires pass through the rotating part at the center of the second conductive slip ring 26 to avoid wire tangling.

[0091] The second hobbing gear 27 has a cylindrical structure and its axial dimension is smaller than that of the second fixed base 241. The interior of the second hobbing gear 27 is axially connected to form a space for the fourth rotor 243 to pass through. The second hobbing gear 27 is fitted onto the fourth rotor 243 and is axially arranged in the fourth direction. The second hobbing gear 27 is connected to the outer ring of the sixth bearing 2416. On the outer wall of the second hobbing gear 27, there are second strip teeth 271 distributed circumferentially along the second hobbing gear 27 for meshing and coupling output power, and second annular teeth 272 formed on one side of the outer wall of the second hobbing gear 27 for sliding output engagement. The second strip teeth 271 are distributed sequentially along the circumference of the second hobbing gear 27, and a second conventional tooth groove is formed between two adjacent second strip teeth 271. When the second hobbing gear 27 rotates in the fourth direction (i.e., the circumferential direction of the second hobbing gear 27 itself), the second strip teeth 271 can drive the gear structure of the joint output unit 3 to rotate in the fourth direction through the second conventional tooth groove to achieve meshing engagement. When the second hob 27 rotates along the axis of the third direction (i.e., the circumferential direction of the second base 211), the second strip tooth 271 can drive the matching gear structure with the same function to rotate in the fourth direction to achieve coupling. The second hob 27 can achieve power output of dual-axis rotation in the third and fourth directions by rotating alternately or simultaneously along the circumferential direction of the second base 211 and its own circumferential direction. The integration and state switching of two transmission modes are realized through one second hob 27, which greatly simplifies the mechanical structure, reduces the number of parts, and is one of the key factors in realizing the miniaturization of the entire second joint drive unit 2. It improves the redundancy and reliability of the system and achieves lightweighting.

[0092] The second annular tooth 272 comprises, from the inside out, a second tooth protrusion 2721 and a second annular tooth 2722 surrounding the outer periphery of the second tooth protrusion 2721. The second annular tooth 2722 can be configured as multiple rings, with the curvature of the second annular tooth 2722 gradually decreasing towards the outside until it matches the second strip tooth 271, and the two ends of the second annular tooth 2722 gradually extending outwards. Specifically, the second annular tooth 2722 includes a plurality of continuous second annular teeth and a plurality of discontinuous second annular teeth symmetrically distributed on both sides of the outer periphery of each continuous second annular tooth. Second arc-shaped tooth grooves are formed between adjacent second tooth protrusions 2721 and continuous second annular teeth, between two adjacent continuous second annular teeth, between adjacent continuous second annular teeth and discontinuous second annular teeth, and between two adjacent discontinuous second annular teeth, so that the second annular tooth 272 can mesh with other gear structures. Multiple consecutive second ring teeth form continuous second arc-shaped tooth grooves on the outer periphery of the second tooth protrusion 2721, while second discontinuous tooth grooves form discontinuous second arc-shaped tooth grooves with open ends on the outer periphery of the second tooth protrusion 2721 and the second consecutive ring teeth. When the second ring tooth 272 meshes with other gear structures with the same structure, the operation of the third drive unit 22 will drive the second hob 27 to rotate around the third direction. At this time, the second ring tooth 272 slides with the gear structure with the same structure without interfering with each other. This can be used to adjust the position between the second hob 27 and other gear structures. When the fourth drive unit 24 is running, the second ring tooth 272 can achieve the same function as the second strip tooth 271 and can mesh with other gear structures to drive them to rotate around the fourth direction. In this way, even if there is only one second hob 27, it can be used for multi-axis rotation output, achieving multi-degree-of-freedom power output while ensuring a small number of parts. The structure of the second hobbing tooth 27 is referenced to that of the first hobbing tooth 17. The first annular tooth 172 and the second annular tooth 272 are both considered as first annular teeth; the first strip tooth 171 and the second strip tooth 271 are both considered as strip teeth; the first continuous annular tooth and the second continuous annular tooth are both considered as continuous annular teeth; the first discontinuous annular tooth and the second discontinuous annular tooth are both considered as discontinuous annular teeth; and the first arc-shaped tooth groove and the second arc-shaped tooth groove are both considered as arc-shaped tooth grooves. The first conventional tooth groove and the second conventional tooth groove are both considered as meshing clearances. The strip teeth have a first curved tooth edge that is concave in the middle along the length direction, and the first annular teeth all have a second curved tooth edge.

[0093] Please see Figure 21 and Figure 22The joint output unit 3 includes a third housing assembly 31 connected to the first housing assembly 13 and the second housing assembly 23, and a spherical tooth 32 with a movable device inside the third housing assembly 31 and driven by the first hobbing gear 17 and the second hobbing gear 27. The third housing assembly 31 supports the spherical tooth 32 and restricts its translational degree of freedom, allowing the spherical tooth 32 to rotate only around its center with three degrees of freedom. The first hobbing tooth 17 of the first joint drive unit 1, the second hobbing tooth 27 of the second joint drive unit 2, and the spherical tooth 32 cooperate to realize two sets of dual-axis equivalent drives. The first hobbing tooth 17 and the spherical tooth 32 realize two-dimensional driving capabilities in the first and second directions, and the second hobbing tooth 27 and the spherical tooth 32 realize two-dimensional driving capabilities in the third and fourth directions. The entire robot joint module has a redundant drive structure with four drive units (i.e., the first drive unit 12, the second drive unit 14, the third drive unit 22, and the fourth drive unit 24) to realize the output rotational degrees of freedom in the first, second, third, and fourth directions. Through the superposition and cooperative drive of the first hobbing tooth 17 and the second hobbing tooth 27 in different positions of the spherical tooth 32, continuous and controllable output in multiple angles (i.e., three degrees of freedom) is realized. Furthermore, by using the assembly phase constant of the first joint drive unit 1 and the second joint drive and the geometric relationship of the entire module, the target attitude is mapped to the target angle of the four drive units through inverse kinematics. The four drive units are then driven to perform in coordination through synchronous interpolation and closed-loop synchronous control based on feedback from each magnetic encoder, so as to reduce the meshing impact caused by the single drive unit moving first. The jitter caused by the side clearance direction switching is suppressed through synchronous constraints and phase coordination under redundant drive, thereby achieving stable tracking of the three-degree-of-freedom attitude.

[0094] Please see Figure 1 , Figure 23 and Figure 24The third housing assembly 31 includes a third housing 311, which is hollow and has a spherical cavity 312 adapted to the shape of the spherical teeth 32. The spherical teeth 32 are installed in the spherical cavity 312, and the surface of the spherical teeth 32 slides in contact with the cavity wall of the spherical cavity 312, thereby supporting the spherical teeth 32 while restricting their translational freedom so that the spherical teeth 32 can only rotate around their own center. A first mounting surface 313 is formed on the end face of the third housing 311 corresponding to the first housing 131 with a first output port 1311, and a second mounting surface 314 is formed on the end face of the first housing segment 231a of the third housing 311 corresponding to the second housing 231 with a second output port 2311, and a second mounting surface 314 is formed on the end face of the first housing segment 231a of the third housing 311 corresponding to the second housing 231 with a second output port 2311. A first input port 315 is provided on the first assembly surface 313, which connects to the spherical cavity 312 and allows a portion of the spherical teeth 32 to extend into it. The portion of the first hob 17 extending out of the first output port 1311 passes into the first input port 315 and meshes with the spherical teeth 32. A second input port 316 is provided on the second assembly surface 314, which connects to the spherical cavity 312 and allows a portion of the spherical teeth 32 to extend into it. The portion of the second hob 27 extending out of the second output port 2311 passes into the second input port 316 and meshes with the spherical teeth 32.

[0095] To ensure a reasonable arrangement of the entire robot joint module and its ease of application to robot joints, the first input port 315 is axially arranged along the first direction, the second input port 316 is axially arranged along the third direction, and the first direction is perpendicular to the third direction, while the fourth direction is perpendicular to both the first and third directions. It should be noted that the settings of the first and third directions are defined by an installation phase constant. This installation phase constant is used to characterize the meshing orientation of the first joint drive unit 1 and the second joint drive unit 2, as well as the sign convention for each click's positive direction, and is not limited to the arrangement described in the aforementioned embodiment.

[0096] To make the output of the spherical teeth 32 more uniform, the third housing 311 also has an arc-shaped surface corresponding to the first mounting surface 313 and the second mounting surface 314. The first mounting surface 313 and the second mounting surface 314 are symmetrically arranged with respect to the arc-shaped surface. A third output port 317 communicating with the spherical cavity 312 is opened at the center of the arc-shaped surface. Part of the spherical teeth 32 protrudes from the third output port 317 out of the spherical cavity 312 to enable the spherical teeth 32 to connect with external mechanical equipment, such as a robotic arm. The third output port 317 has a perimeter 3171 that simulates the rotation angle of the ball-and-socket joint and limits the rotation range of the output end 324. The perimeter 3171 is generally circular or elliptical, or it can be other regular shapes that are approximately elliptical. The specific shape is set according to the required rotation angle and range of the spherical teeth 32 to ensure that it conforms to the range of ball-and-socket posture output, such as the range of motion of the shoulder joint, hip joint, etc., so that the spherical teeth 32 have three degrees of freedom of bionic operation capability. The size of the third output port 317 should be smaller than the diameter of the spherical tooth 32 to prevent the spherical tooth 32 from detaching.

[0097] Please see Figure 25 The spherical tooth 32 is spherical with a spherical surface. Several meshing teeth 321 are arranged on the spherical surface, covering the entire surface. Each spherical tooth 32 is evenly arranged according to a specific pattern. One meshing tooth 321 can be used as a reference, and the other meshing teeth 321 are arranged in multiple circles around the reference meshing tooth 321. Any two adjacent meshing teeth 321 are distributed circumferentially along the spherical surface; that is, any two adjacent meshing teeth 321 are on the same circumference or on two intersecting circumferences, making the entire spherical tooth 32 a cross-spherical gear with an orthogonal spherical tooth structure. The strip teeth of the first hob 17 and the second hob 27 can mesh with the meshing teeth 321 (i.e., conventional gear meshing transmission), or engage in coupling or sliding engagement. When the strip teeth mesh with the meshing teeth 321, the meshing of the strip teeth with the meshing teeth 321 causes the spherical tooth 32 to rotate in the opposite direction relative to the movement of the first hob 17 or the second hob 27. When the strip tooth is coupled with the meshing tooth 321, the strip tooth is locked in the running direction of the first hob 17 or the second hob 27. Therefore, the movement of the strip tooth causes the spherical tooth 32 to rotate in the same direction. When the strip tooth is in sliding engagement with the meshing tooth 321, there is no locking between the strip tooth and the meshing tooth 321 in the running direction. The slidingly engaged strip tooth and meshing tooth 321 slide relative to each other along the extension direction of the strip tooth and the circumferential direction of the meshing tooth 321. That is, the meshing tooth 321 can slide along the meshing gap or the arc-shaped tooth groove.

[0098] A transitional tooth band 322 is formed around the spherical tooth 32, coupling with the strip tooth and meshing with the first ring tooth. The transitional tooth band 322 includes several long teeth 3221, and can also mesh and slide with the strip tooth. At least two second ring teeth 323 are formed on the transitional tooth band 322, which can slide with the first ring tooth. Unlike the first ring tooth, the second ring tooth 323 is not a continuous ring. The second ring tooth 323 is formed by a combination of gradually shortened long teeth 3221 and adjacent meshing teeth 321, and the overall shape is basically adapted to the first ring tooth. With each second ring tooth 323 as the center, each meshing tooth 321 or long tooth 3221 is circumferentially distributed from the inside to the outside, and each long tooth 3221 forms a ring with multiple meshing teeth 321. In this embodiment, the spacing of the second ring teeth 323 corresponds to the position and distance of the first hobbing teeth 17 and the second hobbing teeth 27. The invention arranges the first and third directions perpendicularly. Therefore, a second ring tooth 323 can be provided at each quarter of the transition tooth strip 322, resulting in a total of four second ring teeth 323. The transition tooth strip 322 between each pair of second ring teeth 323 consists of long teeth 3221 that are adapted to the strip teeth and are substantially longer than the meshing teeth 321. Furthermore, the long teeth 3221 between each pair of second ring teeth 323 are arranged from one side of the second ring teeth 323 towards the center, gradually increasing in length. Each long tooth 3221 has two relatively distributed arc-shaped guide surfaces. The two arc-shaped guide surfaces are arranged in two intersecting circumferential directions and are both in the same circumferential direction as the adjacent meshing teeth 321. The middle of the two arc-shaped guide surfaces protrudes in opposite directions and the curvature directions are set in opposite directions, so that the strip tooth or the first ring tooth can normally cooperate between the meshing tooth 321 and the transition tooth band 322. When the arc-shaped guide surface cooperates with the strip tooth, the arc-shaped guide surface can guide the strip tooth through the curvature direction when it can slide with the strip tooth. At this point, when the strip tooth is located between two adjacent long teeth, the strip tooth can change the rotation direction of the spherical tooth by sliding contact with any arc-shaped guide surface. Simultaneously, the first hob 17 and the second hob 27 can also adjust their rotation direction through the arc-shaped guide surface. The adjustment method involves adjusting the rotation angle of the first hob 17 around the X-axis (or the rotation angle of the second hob 27 around the Y-axis) until the strip tooth is adapted to the circumferential direction along the curvature of one of the arc-shaped guide surfaces. This is used to adjust the output rotation direction of the spherical tooth 32, and also to adjust the fit between the first hob 17 or the second hob 27 and the spherical tooth 32, such as changing from a sliding fit to a meshing fit. After the strip tooth meshes with the long tooth 3221, it can mesh circumferentially along the transition tooth band 322. The strip tooth and the long tooth 3221 can also slide along the meshing gap. Theoretically, the strip tooth and the long tooth 3221 can also achieve a coupling fit.To avoid interference when the long teeth 3221 mesh with the strip teeth or the second ring teeth 323, each long tooth 3221 is spaced apart from its corresponding gap when it extends into the meshing gap or the arc-shaped tooth groove. The strip teeth have a first curved tooth edge that is concave in the middle along their length. When the long teeth 3221 mesh with the strip teeth, they can freely engage with the strip teeth. Simultaneously, the tooth structure of the surface of the spherical teeth 32 allows the strip teeth to engage with the long teeth 3221, while both ends of the strip teeth can engage with the meshing teeth 321. The teeth 3221 and the meshing teeth 321 are all gradually narrowed outwards. The length of the long teeth 3221 should be shorter than the length of the strip teeth to ensure smooth engagement between the long teeth 3221 and the strip teeth, as well as between the long teeth 3221 and the first ring teeth, preventing jamming.

[0099] In this embodiment, since the spherical tooth 32 is driven by the first hob 17 and the second hob 27, and both the first hob 17 and the second hob 27 are dual-axis drives, there is a possibility that the first hob 17 and the second hob 27 may interfere with the drive of the spherical tooth 32, causing jamming. The transition tooth strip 322 is mainly used for sliding and meshing with the strip tooth. Taking the first hob 17 as an example, the second hob 27 normally drives the spherical tooth 32 to rotate. When the strip tooth of the first hob 17 is about to interfere with the meshing tooth 321 of the spherical tooth 32, or when the drive output direction of the first hob 17 and / or the second hob 27 on the spherical tooth 32 needs to be adjusted, and the first ring teeth of the first hob 17 and the second hob 27 are not engaged with the second ring tooth 323, the strip tooth of the first hob 17 can continue to run according to the normal motion trajectory. When the transition tooth belt 322 is in operation, the strip tooth can be angled along the arc direction of the desired arc guide surface when it passes through the arc guide surface of the long tooth 3221. Even after the first drive unit 12 controls the first hob 17 to rotate around the X-axis to the desired angle, the second drive unit 14 can drive the first hob 17 to rotate, so that the strip tooth can mesh with the meshing tooth 321 in the circumferential direction of the corresponding arc guide surface and the circumferential direction parallel to it. In this way, the multi-directional rotation output of the spherical tooth 32 can be controlled, and the second hob 27 operates in the same logic. When the first hob 17 or the second hob 27 needs to be adjusted by a large angle, it can also be achieved through the sliding engagement of the intermittent ring tooth and the meshing tooth 321 or the sliding engagement of the intermittent ring tooth and the long tooth 3221. The first ring tooth and the second ring tooth 323 are also used for angle adjustment.

[0100] The spherical tooth 32 has an output end 324 for connecting to an external robotic arm or other equipment. The output end 324 is a flange shaft 3241 that extends out of the spherical tooth 32 and the third output port 317, and the output end 324 is located at the middle of the transition toothed band 322 between the two second ring teeth 323.

[0101] During assembly of the second joint drive unit 2 of the present invention, the sixth bearing 2416 on the two second end plates 1413 is first installed, and then the fourth stator 242, the fourth rotor 243, and the second hobbing gear 27 are installed in place. Then, the fourth drive unit 24 and the second hobbing gear 27 are placed between the two second connecting surfaces 2141. After the fourth drive unit 24 is fixed to the second transmission arm 212 via the second connecting hole 2142 using a connector, the third channel 251 and the fourth channel 252 allow the wiring of the fourth drive unit 24 to be laid out and converge into the second conductive slip ring 26. Then, the fourth rotor 243 is fitted onto the second mating surface 2131 along a third direction, with the second abutment surface 2132 restricting its movement. The fourth rotor 243 is assembled by sequentially mounting the third magnetic ring 224 and the fourth bearing 2322 onto the fourth surrounding section 213b, installing the third bearing 2315 into the sixth groove 2312, and installing the fourth stator 242 into the second housing section 231b. After sequentially installing the fourth magnetic encoder 244, the second rear cover 232, and the second conductive slip ring 26, the second housing 231 and the second rear cover 232 are finally connected and fixed, so that the wiring of the fourth drive unit 24 passes through the second conductive slip ring 26, and the wiring of the third drive unit 22 passes through the hole structure on the fourth magnetic encoder 244. Finally, the second housing assembly 23 surrounds the second transmission arm 212, thus completing the integrated installation of the second joint drive unit 2.

[0102] One embodiment of the robot joint module of the present invention operates as follows: For ease of understanding, the space is divided into three mutually perpendicular axes: X-axis, Y-axis, and Z-axis, with the first direction considered as the X-axis and the third direction as the Y-axis (e.g., ...). Figure 1 (As shown) so that the first joint drive unit 1 and the second joint drive unit 2 can be L-shaped, thereby effectively reducing the space ratio when installed on the robot.

[0103] First, please refer to Figure 26 and Figure 27 In the initial state, the second direction of the first hobbing tooth 17 and the fourth direction of the second hobbing tooth 27 are both distributed along the Z-axis, and the first ring tooth 1722 is engaged with one of the second ring teeth 323, and the second hobbing tooth 27 is engaged with the other second ring tooth 323.

[0104] Second, the first drive unit 12 operates, causing the first hobbing gear 17 to rotate 90° around the X-axis (first direction) in the positive direction, and the third drive unit 22 operates, causing the second hobbing gear 27 to rotate 90° around the Y-axis (third direction) in the positive direction, as follows. Figure 26 As shown in A; during rotation, the sliding engagement of the first ring tooth and the second ring tooth 323 ensures that the rotation of the first hobbing tooth 17 and the second hobbing tooth 27 does not affect the spherical tooth 32, and the state after rotation is as follows. Figure 26 As shown in B, the second direction is arranged along the Y-axis and the fourth direction is arranged along the X-axis.

[0105] Third, the fourth drive unit 24 operates, causing the second hobbing gear 27 to rotate 180° in the positive direction of the fourth direction (X-axis at this time), so that the second annular tooth 2722 and the strip tooth gradually engage with the meshing tooth 321, causing the spherical tooth 32 to rotate 90°. At this time, the second annular tooth 2722 and the second annular tooth 323 continue to slide to ensure independent engagement between the second hobbing gear 27 and the spherical tooth 32. The second annular tooth 2722 can also ensure that the spherical tooth 32 does not deflect at this time and is stably engaged with the second hobbing gear 27, keeping it stable. At this time, the strip tooth of the second hobbing gear 27 matches the meshing tooth 321, and the transition tooth band 322 corresponds circumferentially to the first hobbing gear 17, such as... Figure 26 As shown in C, for this purpose, the meshing of any hob with the spherical tooth 32 can be used to adjust the positional relationship between another hob and the transition tooth band 322 on the spherical tooth 32.

[0106] Fourth, the second drive unit 14 drives the first hobbing gear 17 to rotate 180° in the positive direction of the second direction (Y-axis at this time), so that the first annular tooth 1722 and the strip tooth gradually mesh with the transition tooth belt 322, causing the spherical tooth 32 to rotate 90° around the Y-axis. During the rotation, the second hobbing gear 27 couples with the meshing tooth 321 through the strip tooth. The third drive unit 22 then drives the second hobbing gear 27 to rotate 90° in the positive direction of the Y-axis (third direction). The state after rotation is as follows. Figure 26 As shown in D in the diagram. At this time, the second direction is arranged along the Y-axis, the fourth direction is arranged along the Z-axis, and the strip teeth of the first hobbing gear 17 are engaged with the transition tooth belt 322.

[0107] Fifth, the first drive unit 12 drives the first hobbing gear 17 to rotate 90° around the X-axis. The strip tooth, through coupling with the second ring tooth 323, drives the spherical tooth 32 to rotate 90° around the X-axis. At this time, the meshing clearance of the strip tooth of the second hobbing gear 27 is adapted to the circumferential direction of the corresponding meshing tooth 321 of the spherical tooth 32, so that the strip tooth of the second hobbing gear 27 slides with the meshing tooth 321. The state after rotation is as follows. Figure 26 As shown in E in the diagram. At this time, the first hobbing tooth 17 and the second hobbing tooth 27 respectively mesh with a second ring tooth 323, that is, the meshing tooth 321 extends into the meshing gap, and the second direction of the first hobbing tooth 17 and the fourth direction of the second hobbing tooth 27 are both arranged along the Z-axis.

[0108] Sixth, the second drive unit 14 operates, causing the first hobbing gear 17 to rotate 180° around the second direction and mesh with the transition tooth belt 322; the fourth drive unit 24 operates, causing the second hobbing gear 27 to rotate 180° around the fourth direction and mesh with the transition tooth belt 322; the spherical tooth 32 rotates 90 degrees around the Z-axis. The state after rotation is as follows. Figure 27 As shown in F, the first ring tooth 1722 engages with one of the second ring teeth 323, and the second ring tooth 2722 engages with the other second ring tooth 323. In summary, the alternating engagement, coupling, and sliding engagement of the first hobbing tooth 17 and the second hobbing tooth 27 with the spherical tooth 32 enables the spherical tooth 32 to rotate alternately on the X-axis, Y-axis, and Z-axis.

[0109] Seventh, the first drive unit 12 is driven to rotate the first hobbing gear 17 45° around the X-axis, and the third drive unit 22 is driven to rotate the second hobbing gear 27 45° around the Y-axis. Since both the first ring gear 1722 and the second ring gear 2722 are engaged with the second ring gear 323 at this time, the spherical gear 32 is unaffected during movement. The rotated state is as follows: Figure 27 As shown in G.

[0110] Eighth, next, the first drive unit 12, the second drive unit 14, the third drive unit 22, and the fourth drive unit 24 will jointly drive the first hobbing gear 17 and the second hobbing gear 27 to operate. The second drive unit 14 drives the first hobbing gear 17 to mainly mesh with the meshing tooth 321, thereby causing the spherical tooth 32 to rotate in the opposite direction to the rotation direction of the first hobbing gear 17. The fourth drive unit 24 drives the second hobbing gear 27 to mainly mesh with the meshing tooth 321, thereby causing the spherical tooth 32 to rotate in the opposite direction to the rotation direction of the second hobbing gear 27. However, it should be ensured that the rotation of the first hobbing gear 17 and the second hobbing gear 27 does not interfere with each other. When the strip tooth of the first hobbing gear 17 rotates to mesh with the transition tooth belt 322, the first drive unit 12 drives the first hobbing gear 17 to rotate and adjust its direction, thereby ensuring that the engagement between the first hobbing gear 17 and the second hobbing gear 27 does not cause obstruction and avoids interference. Figure 27 H to Figure 27As shown in Figure I. When the strip tooth of the second hobbing tooth 27 rotates to engage with the transition tooth strip 322, the third drive unit 22 also drives the second hobbing tooth 27 to adjust its direction, thereby avoiding interference while ensuring that the first hobbing tooth 17 and the second hobbing tooth 27 can continue to engage with the spherical tooth 32. During the engagement of the strip tooth with the long tooth 3221 of the transition tooth strip 322, the long tooth 3221 extends into the meshing tooth 321, and the strip tooth usually slides with the longer long tooth 3221 between two adjacent second ring teeth 323 (guided sliding is achieved through the curvature of the arc guide surface, thereby changing the direction of the spherical tooth 32 to a certain extent). At the same time, the first hobbing tooth 17 also rotates around the X-axis during the sliding engagement through the operation of the first drive unit 12, so as to change the orientation of the second direction and compound coupling by rotating the first hobbing tooth 17. After changing the rotation direction of the spherical tooth 32, the sliding engagement continues until the strip tooth meshes with the meshing tooth 321. Simultaneously, the rotation angle of the first hob 17 needs to accommodate the continued engagement of the second hob 27 with the spherical tooth 32. Therefore, when the first hob 17 changes its orientation in the second direction, the second hob 27 also needs to adapt to the rotation of the spherical tooth 32 and the first hob 17 by changing its orientation in the fourth direction through the transition tooth strip 322, to avoid interference and locking of the first hob 17 and the second hob 27 in driving the spherical tooth 32. When significant interference is imminent after the first hob 17 or the second hob 27 rotates, and a small arc cannot prevent interference, one of the second ring teeth 323 of the spherical tooth 32 can be rotated to engage with the first ring tooth of any hob. For example, after the first ring tooth 1722 of the first hob 17 engages with the second ring tooth 323, the first drive unit 12 drives the first hob 17 to rotate 180° (not limited to 180°) around the X-axis. Figure 27 I to ​As shown in J, the first ring tooth 1722 and the second ring tooth 323 slide into a sliding engagement, with the second ring tooth 323 sliding along the arc-shaped tooth groove. The outward-facing first ring tooth 1722 allows the second ring tooth 323 to slide out of the arc-shaped tooth groove. This large-angle change in the orientation of the second direction allows the engagement between the first hobbing tooth 17 and the spherical tooth 32 to return to a basic engagement state, as described in the first to seventh descriptions above, thereby adjusting the control range of the spherical tooth 32. Thus, either the first hobbing tooth 17 or the second hobbing tooth 27 can become the meshing drive component driving the spherical tooth 32 itself, thereby providing meshing transmission along a specific direction to the spherical tooth 32. The other hobbing tooth 17 or the second hobbing tooth 27, through the drive of the first drive unit 12 or the third drive unit 22, changes the coupling component of the equivalent line of action direction, used to adjust the equivalent drive axis of the drive unit on the spherical tooth 32. This allows both the first joint drive unit 1 and the second joint drive unit 2 to possess two-dimensional drive capabilities, and through the orthogonal superposition of drive capabilities, controllable three-dimensional drive posture output is achieved. Combined with the setting position of the output end 324, the output shaft achieves multi-axis, multi-degree-of-freedom output oscillation through the coordinated adjustment of the first hobbing tooth 17 and the second hobbing tooth 27.

[0111] It should be noted that the robot joint module also includes a controller electrically connected to the fourth drive unit 24 of the first drive unit 12. The controller is configured to: receive target attitude parameters from the output terminal 324; calculate the target angles of the four drive units based on a preset inverse kinematics mapping relationship; and perform synchronous interpolation and closed-loop synchronous control based on feedback from each magnetic encoder and magnetic ring on the four drive units to drive the output terminal 324 to achieve the target yaw, pitch, and roll attitudes. In terms of control implementation, this embodiment can adopt encoder-based closed-loop synchronous control. The controller describes the target attitude (roll, yaw, pitch) of the output terminal 324 using Euler angles of the X-axis, Y-axis, and Z-axis, and defines the angle quantities of the four drive units (corresponding to the first direction, second direction, third direction, and fourth direction) as the output angles of the first joint drive unit 1 corresponding to the first drive unit 12 and the second drive unit 14, and the output angles of the second joint drive unit 2 corresponding to the third drive unit 22 and the fourth drive unit 24; the relative geometric orientation of the first joint drive unit 1 and the second joint drive unit 2 is determined by the mechanical design and fixed as an installation constant in the control parameters. The control process can be executed according to the following logic: First, initialization and calibration are performed, the zero positions of the first magnetic encoder 123 to the fourth magnetic encoder 244 are read, and a one-to-one correspondence between the angles of each drive unit and the initial pose of the mechanism assembly is established; then, the desired attitude command is received and the attitude range is limited; then, inverse kinematics calculation is performed to obtain the target angles of the four drive units (preferably using dual-parameter arctangent to ensure quadrant correctness); then, trajectory planning and synchronous interpolation are performed to generate a sequence of target angles of the four drive units in the same period to avoid meshing impact caused by the single drive unit moving first; then, the four drive units respectively execute closed-loop control and introduce synchronous constraint terms to ensure that the two drive units in the same joint drive unit meet the preset coupling relationship, and at the same time, phase coordination is performed between the two joint drive units (referring to the first joint drive unit 1 and the second joint drive unit 2) to suppress backlash switching jitter; finally, position determination and continuous tracking are performed to realize continuous attitude control of yaw, pitch, and roll.

[0112] The inverse kinematics calculation takes the target attitude (roll, yaw, pitch) and the installation phase constant Π as input, and outputs a set of target angles for the four drive units. Π includes parameters such as the assembly orientation of the two joint drive units, the convention for the positive direction sign of each drive unit, and the zero-position offset. The inverse kinematics mapping relationship can be implemented using analytical mapping, piecewise mapping, or lookup table interpolation. The lookup table data can be obtained through calibration and embedded in the control parameters. To ensure motion continuity, the target angles of the four drive units output by the inverse kinematics calculation are preferably normalized and the branch continuity is selected. During the synchronous interpolation stage, the four drive units undergo same-period interpolation to meet the synchronous positioning constraint.

[0113] Compared with the prior art, the robot joint module of the present invention integrates the first drive unit 12 and the second drive unit 14 radially on the inner and outer sides of the first drive arm 112 and realizes dual power output, so that the entire first joint drive unit 1 has a smaller axial size, which is suitable for the part of the robot joint module directly exposed outside the torso, reducing obstruction with a smaller volume and space ratio; the second drive arm 212 realizes dual power output in the axial direction by integrating the third drive unit 22 and the fourth drive unit 24, so that the entire second joint drive unit 2 has a smaller radial size, which is suitable for the part of the robot joint module installed inside the torso, that is, the smaller radial size facilitates installation in a relatively narrow space, and the first joint drive unit 1 is shorter than the second joint drive unit 2, which is more reasonable in terms of spatial arrangement; through the cooperative drive of the first joint drive unit 1 and the second joint drive unit 2, a redundant drive structure of four drive units and three degrees of freedom output is formed, so that the first hob 17 and the second hob 27 pass through the intersection of each drive unit. Alternating or compound drives, through meshing, coupling, or sliding engagement, alter the relative positions of the meshing teeth 321 and transition tooth strip 322 on the spherical tooth 32 with respect to the two hobs, thereby changing the relative magnitude and direction of the driving components of the two joint drive units. Without increasing the number of joint series stages, the two-axis driving components of the two joint drive units are superimposed and coordinated to form a three-degree-of-freedom rotational attitude output on the spherical tooth 32. This helps to reduce axial stacking, structural redundancy, and space occupation caused by multi-joint series, and improves system integration and installation compactness. In terms of control implementation, magnetic encoders and magnetic rings are used as feedback. The target attitude is mapped to the target angle of the four drive units through inverse kinematics. Combined with synchronous interpolation and closed-loop synchronous control, the four drive units are coordinated to execute within the same cycle. This helps to avoid meshing impact caused by the linearity of a single drive unit. Furthermore, the synchronous constraints and phase coordination under redundant drives reduce the jitter caused by the switching of meshing backlash direction, thereby improving the stability and repeatability of attitude tracking.

Claims

1. A robot joint module, characterized in that, The utility model relates to a joint driving device, comprising: a first joint driving unit, the first joint driving unit comprising a first shift fork structure, a first rack gear connected to the first shift fork structure, a first driving part connected to the first shift fork structure and used for driving the first shift fork structure to rotate around a first direction to output, a second driving part connected to the first shift fork structure and used for driving the first rack gear on the first shift fork structure to rotate around a second direction to output, and a first housing assembly sleeved on the first driving part; a second joint driving unit, the second joint driving unit comprising a second shift fork structure, a second rack gear connected to the second shift fork structure, a third driving part connected to the second shift fork structure and used for driving the second shift fork structure to rotate around a third direction to output, a fourth driving part connected to the second shift fork structure and used for driving the second rack gear to rotate around a fourth direction to output, and a second housing assembly sleeved on the second shift fork structure and the third driving part; and a joint output unit, the joint output unit comprising a third housing assembly connected to the first housing assembly and the second housing assembly respectively, and a spherical gear in the third housing assembly and transmission matched to the first rack gear and the second rack gear respectively, the spherical gear having an output end outputting power with multiple degrees of freedom when the first rack gear and the second rack gear rotate.

2. The robotic joint module of claim 1, wherein: The first joint driving unit is arranged along the first direction, and the second joint driving unit is arranged along the third direction. The first joint driving unit is shorter than the second joint driving unit.

3. The robot joint module according to claim 1 or 2, characterized in that: The first shift fork structure comprises a first base and two first transmission arms connected to the first base and arranged along the second direction, the first driving part is mounted on the first base, and the first driving part is arranged around the periphery of the first transmission arms, and the second driving part is mounted between the two first transmission arms. The second shift fork structure comprises a second base and two second transmission arms connected to the second base and arranged along the fourth direction, the second base is formed with an extension shaft extending along the third direction, the third driving part is coaxially mounted on the extension shaft, and the fourth driving part is mounted between the two second transmission arms.

4. The robotic joint module of claim 1, wherein: The first driving part comprises a first rotor sleeved on the first shift fork structure and a first stator arranged around the periphery of the first rotor, and the first rotor is sleeved with a first magnetic encoder and a first magnetic ring. The first housing assembly comprises a first housing sleeved on the periphery of the first rotor and a first back cover sleeved on the periphery of the first rotor and coaxially connected to the first housing, the first stator is mounted in the first housing, and the first housing is provided with a first output port for part of the first rack gear to extend out; a first bearing is arranged between the first housing and the first rotor to enable the first rotor to rotate relative to the first housing, a second bearing is arranged between the first back cover and the first rotor to enable the first rotor to rotate relative to the first back cover, a first pre-tightening space is arranged around the second bearing, the first rotor and the first back cover, a first spring is arranged in the first pre-tightening space and elastically abuts against the second bearing and the first back cover along the first direction, and the first spring is configured as a first wave spring.

5. The robotic joint module of claim 4, wherein: The third driving part comprises a third rotor sleeved on the second shift fork structure and a third stator surrounding the third rotor, and the third rotor is sleeved with a third magnetic encoder and a third magnetic ring; The second shell assembly comprises a second shell sleeved on the outer periphery of the second shift fork structure and a second back cover sleeved on the outer periphery of the second shift fork structure and coaxially connected to the second shell, and the third stator is installed in the second shell, and the second shell has a second output port for part of the second gear hob to protrude out; The third bearing is arranged between the second shell and the second shift fork structure to enable the second shift fork structure to rotate relative to the second shell, and the fourth bearing is arranged between the second back cover and the second shift fork structure to enable the second shift fork structure to rotate relative to the second back cover, and a second pre-tightening space is formed between the fourth bearing, the second shift fork structure and the second back cover, and a second spring is arranged in the second pre-tightening space to elastically abut against the fourth bearing and the second back cover in the third direction, and the second spring is configured as a second wave spring.

6. The robotic joint module of claim 5, wherein: The first back cover has a first wall surface connected to the outer ring of the second bearing, and the first rotor has a first matching surface connected to the inner ring of the second bearing and abutting against the second bearing away from the second spring in the first direction; The second back cover has a second wall surface connected to the outer ring of the fourth bearing, and one end of the second shift fork structure has a second matching surface connected to the inner ring of the fourth bearing and abutting against the fourth bearing away from the second spring in the first direction.

7. The robotic joint module of claim 3, wherein: The two first transmission arms each have a first connecting surface formed on one side facing each other, the second driving part comprises a first fixed seat connected to the two first connecting surfaces respectively, a second stator sleeved on the first fixed seat and a second rotor movably sleeved on the outer periphery of the second stator, the second magnetic encoder is arranged on the first transmission arm, the fifth bearing is arranged between the two ends of the second rotor and the two ends of the fixed seat to enable the second rotor to rotate relative to the first fixed seat, and the first gear hob is sleeved on the second rotor and connected to the fifth bearing; The two second transmission arms each have a second connecting surface formed on one side facing each other, the fourth driving part comprises a second fixed seat connected to the two second connecting surfaces respectively, a fourth stator sleeved on the second fixed seat and a fourth rotor movably sleeved on the outer periphery of the fourth stator, the fourth magnetic encoder is arranged on the second transmission arm, the sixth bearing is arranged between the two ends of the fourth rotor and the two ends of the second fixed seat to enable the fourth rotor to rotate relative to the second fixed seat, and the second gear hob is sleeved on the fourth rotor and connected to the sixth bearing.

8. The robotic joint module of claim 7, wherein: The first wiring channel and the second wiring channel are further included; The first wiring channel comprises a first channel opened in the first fixed seat and communicated to the second stator, and a second channel communicated to the first channel and opened to the first shift fork structure, and the first joint driving unit further comprises a first conductive slip ring connected to the first shell assembly and communicated to the second channel in the first direction; The third driving part comprises a third rotor sleeved on the second shift fork structure and a third stator surrounding the third rotor, and the third rotor is sleeved with a third magnetic encoder and a third magnetic ring; The second shell assembly comprises a second shell sleeved on the outer periphery of the second shift fork structure and a second back cover sleeved on the outer periphery of the second shift fork structure and coaxially connected to the second shell, and the third stator is installed in the second shell, and the second shell has a second output port for part of the second gear hob to protrude out; The third bearing is arranged between the second shell and the second shift fork structure to enable the second shift fork structure to rotate relative to the second shell, and the fourth bearing is arranged between the second back cover and the second shift fork structure to enable the second shift fork structure to rotate relative to the second back cover, and a second pre-tightening space is formed between the fourth bearing, the second shift fork structure and the second back cover, and a second spring is arranged in the second pre-tightening space to elastically abut against the fourth bearing and the second back cover in the third direction, and the second spring is configured as a second wave spring. The first back cover has a first wall surface connected to the outer ring of the second bearing, and the first rotor has a first matching surface connected to the inner ring of the second bearing and abutting against the second bearing away from the second spring in the first direction; The second back cover has a second wall surface connected to the outer ring of the fourth bearing, and one end of the second shift fork structure has a second matching surface connected to the inner ring of the fourth bearing and abutting against the fourth bearing away from the second spring in the first direction. The two first transmission arms each have a first connecting surface formed on one side facing each other, the second driving part comprises a first fixed seat connected to the two first connecting surfaces respectively, a second stator sleeved on the first fixed seat and a second rotor movably sleeved on the outer periphery of the second stator, the second magnetic encoder is arranged on the first transmission arm, the fifth bearing is arranged between the two ends of the second rotor and the two ends of the fixed seat to enable the second rotor to rotate relative to the first fixed seat, and the first gear hob is sleeved on the second rotor and connected to the fifth bearing; The two second transmission arms each have a second connecting surface formed on one side facing each other, the fourth driving part comprises a second fixed seat connected to the two second connecting surfaces respectively, a fourth stator sleeved on the second fixed seat and a fourth rotor movably sleeved on the outer periphery of the fourth stator, the fourth magnetic encoder is arranged on the second transmission arm, the sixth bearing is arranged between the two ends of the fourth rotor and the two ends of the second fixed seat to enable the fourth rotor to rotate relative to the second fixed seat, and the second gear hob is sleeved on the fourth rotor and connected to the sixth bearing. The second wiring channel comprises a third channel in the second fixing seat and communicated to the fourth stator, and a fourth channel communicated to the third channel and opened to the second fork structure, and the second joint driving unit further comprises a second conductive slip ring connected to the second shell assembly and communicated to the fourth channel in the third direction.

9. The robotic joint module of claim 1, wherein: The surface of the spherical tooth has a spherical surface, and a plurality of engagement teeth are distributed on the spherical surface in a circumferential direction of the spherical surface; The outer side wall of the first and second gear teeth is formed with a strip-shaped tooth distributed in a circumferential direction of the axis and used for engaging, coupling and sliding with the engagement teeth; The strip-shaped tooth has a first curved tooth edge recessed in a middle part in a length direction.

10. The robotic joint module of claim 9, wherein: The outer side wall of the first and second gear teeth is further formed with a first ring tooth in a multilayer annular shape, and the spherical tooth is formed with a plurality of transition tooth belts coupled with the strip-shaped tooth and engaged with the first ring tooth along a circumferential direction of the spherical tooth, and the transition tooth belt is formed with at least two second ring teeth slidingly engaged with the first ring tooth and used for coupling the strip-shaped tooth. The first ring tooth has a second curved tooth edge spaced from the transition tooth belt in a circumferential direction of the gear tooth. The third shell assembly is formed with a third output port through which the output end of the spherical tooth is movably arranged, and the third output port has a surrounding edge simulating a spherical cavity to limit a rotation angle of the output end.

11. The robotic joint module of claim 10, wherein: The first ring tooth comprises a tooth protrusion and an annular tooth annularly arranged outside the tooth protrusion, the annular tooth has a plurality of continuous annular teeth in an annular and continuous shape and a plurality of discontinuous annular teeth symmetrically arranged outside the continuous annular teeth, and an arc-shaped tooth groove is formed between adjacent tooth protrusions, continuous annular teeth, adjacent continuous annular teeth and discontinuous annular teeth, and adjacent discontinuous annular teeth. The curvature of each discontinuous annular tooth gradually decreases outward from the tooth protrusion.

12. The robotic joint module of any of claims 10 to 11, wherein: The transition tooth belt comprises a plurality of long teeth adapted to the strip-shaped tooth and sequentially distributed in a circumferential direction, the long teeth are used for engaging and sliding with the strip-shaped tooth, and the long teeth between any adjacent two second ring teeth are arranged from a side of the second ring tooth to a middle part by gradually increasing in length. The two sides of the long tooth have oppositely distributed arc-shaped guide surfaces, and the bending directions of the two arc-shaped guide surfaces are distributed on two intersecting circumferential directions of the spherical tooth, respectively.

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