Wrist joint of a robot arm, robot arm and robot

Abstract

A wrist joint of a mechanical arm, a mechanical arm and a robot are provided. The wrist joint can include: an end fixing plate for fixing an end effector; a central shaft fixing seat connected to the end fixing plate; a first wire wheel assembly and a second wire wheel assembly symmetrically arranged at first opposite sides of the central shaft fixing seat and rotating relative to an axis of the central shaft fixing seat and rotating according to a driving force based on a wire assembly, respectively; and a connecting mechanism connected with the first wire wheel assembly and the second wire wheel assembly, for connecting the first wire wheel assembly and the second wire wheel assembly to the end fixing plate respectively, so that the end fixing plate rotates according to the rotation of the first wire wheel assembly and the second wire wheel assembly. By arranging at least part of the driving module at the end of the large arm instead of at the joint, the moment of inertia of the end of the mechanical arm can be low, the rotation speed can be fast, and the wrist joint has a larger range of motion and flexibility.

Description

Technical Field

[0001] This application relates to the field of robotics, and more specifically, to a wrist joint of a robotic arm, a robotic arm, and a robot. Background Technology

[0002] With the development of robotics technology, humanoid robots have always been a major direction in robot development, such as the DLR humanoid robotic arm and the HRP series of humanoid robots. These robots share some commonalities: they are all designed by mimicking the structure of the human body and have broad application prospects in manufacturing, medical, and service industries.

[0003] Currently, the robotic arms of these humanoid robots have multiple joints, and each joint is equipped with a drive module (e.g., drive motor and reducer). The drive module is typically quite heavy, perhaps accounting for around 60% of the total weight of the robotic arm. This can result in an excessively large moment of inertia at the end effector, limiting the end effector's speed, preventing high-speed movement, and potentially causing loss of control. Furthermore, humanoid robots are used in human-robot interaction scenarios; in such cases, excessive moment of inertia could potentially cause injury to the person interacting with the robot.

[0004] Therefore, a robotic arm with low end-effector inertia is needed to improve the reliability and safety of the robot. Summary of the Invention

[0005] According to one aspect of this application, a wrist joint in a robotic arm is provided. The wrist joint includes an end effector plate for securing an end effector; a central shaft mount connected to the end effector plate; a first and a second threaded wheel assembly symmetrically disposed on first opposing sides of the central shaft mount and rotatable relative to the axis of the central shaft mount, and respectively rotating according to a driving force based on the threaded assembly; and a connecting mechanism connected to the first and second threaded wheel assemblies for connecting the first and second threaded wheel assemblies to the end effector plate, such that the end effector plate rotates according to the rotation of the first and second threaded wheel assemblies.

[0006] According to some embodiments, each of the first spool assembly and the second spool assembly includes: a spool, on which two linear components are wound in opposite directions, and a first end of each linear component is fixed to the spool shaft, and a second end is connected to an external drive module for rotating according to a driving force based on the linear components from the external drive module.

[0007] According to some embodiments, when the first spool assembly and the second spool assembly both rotate in the same direction of rotation, the end fixing plate can rotate in the tilt direction; and when the first spool assembly and the second spool assembly rotate in different directions of rotation, the end fixing plate can rotate in the pitch direction.

[0008] According to some embodiments, the connecting mechanism includes multiple links, the link sets corresponding to the first reel assembly and the second reel assembly are symmetrical with respect to the central shaft fixing seat, and each link set includes a first link, a second link, and a third link, wherein: the first link connects between a corresponding reel assembly and the second link; the second link connects between the first link and the third link; the third link connects between the second link and the end fixing plate; the first ends of the two fourth links in the connecting mechanism are respectively connected to the second opposite sides of the central shaft fixing seat in a direction perpendicular to the end fixing plate, excluding the first opposite sides, and the second ends are respectively connected to the end fixing plate.

[0009] According to some embodiments, each of the first and second reel assemblies further includes a speed sensor, configured in association with the reel, for detecting the speed of the reel to provide to the processing device.

[0010] According to another aspect of this application, a robotic arm is also provided. The robotic arm includes: a wrist joint, an elbow joint, and a shoulder joint, wherein the wrist joint is a wrist joint as described above; a first robotic arm and a second robotic arm, wherein the arm between the shoulder joint and the elbow joint is the first robotic arm, and the arm between the elbow joint and the wrist joint is the second robotic arm; and a drive module for driving the wrist joint, the elbow joint, and the shoulder joint.

[0011] According to some embodiments, the drive module includes: a first drive module disposed at one end of the first arm near the shoulder joint, and used to control the wrist joint by driving the extension and retraction of a first set of linear components; a second drive module used to drive the elbow joint; and a third drive module integrated with the shoulder joint used to drive the shoulder joint.

[0012] According to some embodiments, the elbow joint includes: a first connecting seat for connecting to the first arm; a second connecting seat for connecting to the second arm; and a pulley mechanism connected to the first and second connecting seats for moving the second arm toward the first arm and rotating it away from the first arm based on the retraction and extension of a second set of linear components, wherein the second set of linear components forms a movable pulley group with a plurality of linear wheels.

[0013] According to some embodiments, the plurality of spools includes a central large spool and a plurality of small spools. A first portion of the small spools, the central large spool, and a first linear component of the second group of linear components are used to form a first movable pulley group. A second portion of the small spools, the central large spool, and a second linear component of the second group of linear components are used to form a second movable pulley group. When the first linear component is tightened, the central large spool rotates around a pivot, causing the second machine arm to rotate toward the first machine arm. And when the second linear component is tightened, the central large spool rotates around a pivot, causing the second machine arm to rotate away from the first machine arm.

[0014] According to some embodiments, the second drive module is disposed at one end of the first arm near the shoulder joint, and may be integrated with or not integrated with the first drive module.

[0015] According to some embodiments, the first drive module includes two thread drive sub-modules corresponding to the first thread pulley assembly and the second thread pulley assembly, respectively, and the second drive module includes one thread drive sub-module. Each thread drive sub-module includes a thread drive motor and a thread drive shaft. Two thread components in the first group of thread components or the second group of thread components are wound in opposite directions on the corresponding thread drive shaft, and the thread drive shaft included in each thread drive sub-module is driven by the corresponding thread drive motor to drive the tightening of two thread components in the first group of thread components or the second group of thread components.

[0016] According to some embodiments, the first end of each linear component in the first group of linear components is fixed on the corresponding spool drive shaft, and the second end is fixed on the spool shaft after being wound around the spool shaft of one of the first spool assembly and the second spool assembly at the wrist joint via the elbow joint.

[0017] According to some embodiments, the shoulder joint is directly driven by the third drive module, which includes a first drive submodule, a second drive submodule, and a third drive submodule that are perpendicular to each other and correspond to the three degrees of freedom. The first drive submodule is connected to the end of the first arm near the shoulder joint. The second drive submodule is connected to the first arm through a first drive connector, and the third drive submodule is connected to the second drive submodule through a second drive connector.

[0018] According to some embodiments, each of the first drive submodule, the second drive submodule, and the third drive submodule includes a drive motor and an electric shaft corresponding to the drive motor. A first end of the first drive connector is connected to the electric shaft corresponding to the drive motor of the first drive submodule, and a second end is connected to the electric shaft corresponding to the drive motor of the second drive submodule. A first end of the second drive connector is connected to the electric shaft corresponding to the drive motor of the second drive submodule, and a second end is connected to the electric shaft corresponding to the drive motor of the third drive submodule.

[0019] According to another aspect of this application, a robot is also provided, which includes the robotic arm described above.

[0020] The wrist joint, robotic arm, and robot provided according to embodiments of this application, by placing at least a portion of the drive module at the upper arm end rather than at the joint, and employing a wrist joint with a linkage mechanism driven by a linear component, can achieve a lower moment of inertia at the end of the robotic arm, enabling faster rotational speeds, and providing a greater range of motion and flexibility. Furthermore, an elbow joint driven by a linear component and incorporating a pulley system can be optionally used, further reducing the moment of inertia at the end of the robotic arm and increasing the load-bearing capacity of the elbow joint. Additionally, the shoulder joint employs a direct-drive structure, and control is very simple when three degrees of freedom are satisfied. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The following drawings are not intentionally drawn to scale to actual size; their focus is on illustrating the main points of this disclosure.

[0022] Figure 1 A front view of a robotic arm according to an embodiment of this application is shown.

[0023] Figure 2 An overall view of a wrist joint for a robotic arm according to an embodiment of this application is shown. The various components of the wrist joint are illustrated for clarity.

[0024] Figure 3 yes Figure 2 The image shows an exploded view of the wrist joint after it has been horizontally rotated 180° in a horizontal plane.

[0025] Figure 4 A front view of an example elbow joint for a robotic arm according to an embodiment of this application is shown.

[0026] Figure 5 A rear view of an example elbow joint for a robotic arm according to an embodiment of this application is shown.

[0027] Figure 6 It shows Figures 4-5 An exploded view of the elbow joint is shown.

[0028] Figure 7 and Figure 8 A schematic diagram of the movable pulley block of the pulley mechanism is shown.

[0029] Figure 9 A cross-sectional schematic diagram of the first arm at a predetermined space where the first drive module or the second drive module is placed is shown.

[0030] Figure 10 A view of an example shoulder joint for a robotic arm according to an embodiment of this application is shown.

[0031] Explanation of reference numerals in the attached drawings: 1, 200 - Wrist joint; 2, 400 - Elbow joint; 3, 1000 - Shoulder joint; 11 - First arm; 12 - Second arm; 220 - Intermediate shaft mounting base; 230, 235 - Thread reel assembly; 210 - End plate; 240 - Connecting mechanism; 240-1 (245-1) - First link; 240-2 (245-2) - Second link; 240-3 (245-3) - Third link; 250 - Connector; 255 - First flange bearing; 260 - First washer; 265 - First screw; 270 - Lower fisheye bearing; 275 - Upper fisheye bearing; 280 - Second flange bearing; 285 - Second washer Plate; 290-Second screw; 295-Large flange bearing; 410-First connecting seat; 420-Second connecting seat; 430-Pulley mechanism; R1-R10-Small reel; RW-Central large reel; 450-Central support plate; 430-1-Connecting shaft; 430-2-Snap ring; 430-3-Flange bearing; 910-Reel drive motor; 920-Reel drive shaft; 930-Bearing; 1070-Bearing cover plate; 1010-First drive submodule; 1020-Second drive submodule; 1030-Third drive submodule; C1-First drive connecting seat; C2-Second drive connecting seat; 1050-Connector; 1060-Fixing seat Detailed Implementation

[0032] The technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are also within the scope of protection of this disclosure.

[0033] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0034] Furthermore, the following descriptions of the embodiments are with reference to the accompanying illustrations, used to illustrate specific embodiments in which the invention can be implemented. Directional terms used in this invention, such as "long," "left and right," and "up and down," are merely for reference to the accompanying illustrations. Therefore, the use of directional terms is for better and clearer explanation and understanding of the invention, and does not indicate or imply that the referred device or element must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Unless otherwise expressly specified and limited, the terms "installation," "setting," "connection," "linking," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. Those skilled in the art can understand the specific illustrative meaning of the above terms in this invention based on the specific circumstances.

[0035] Artificial intelligence (AI) is the theory, methods, technology, and application systems that use digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to achieve optimal results. In other words, AI is a comprehensive technology within computer science that attempts to understand the essence of intelligence and produce a new kind of intelligent machine that can react in a way similar to human intelligence. AI studies the design principles and implementation methods of various intelligent machines, enabling them to possess the functions of perception, reasoning, and decision-making.

[0036] As mentioned earlier, in order to improve the reliability and safety of robots, a robotic arm with low end-effector inertia is needed.

[0037] One approach is to replace the drive motor and reducer combination with geared motors at each joint. The geared motors directly control the joint rotation, which can reduce weight to some extent and thus lower the rotational inertia of the robotic arm's end effector. However, this method requires dedicated geared motors, increasing costs, and geared motors still have the issue of being slightly heavier.

[0038] Another approach could involve using pneumatic artificial muscle fibers and bionic robotic arms. These arms are driven by pneumatic artificial muscle bundles and have variable stiffness. When colliding with other objects, the flexibility of the pneumatic muscles helps to absorb some of the force, improving safety in human-computer interaction. However, this approach still reduces the overall stiffness of the robot, lowers control precision, and remains too costly.

[0039] In the field of human-computer interaction, another approach is to add joint force sensors to obtain external interaction information and take appropriate adjustment strategies when in contact with or interacting with people. However, this method is limited by the control response speed and the reliability of the sensors.

[0040] In addition, the range of motion and flexibility of the robotic arm's joints, as well as its load-bearing capacity, are also important factors in evaluating a robot's performance.

[0041] Therefore, to address the problems of existing methods, embodiments of this application provide a robotic arm that, by placing at least a portion of the drive module at the upper arm end rather than at the joint, employs a wrist joint with a linkage mechanism driven by a linear component. This results in a lower moment of inertia at the robotic arm's end, enabling faster rotational speeds, and providing a greater range of motion and flexibility. Furthermore, optionally utilizing an elbow joint driven by a linear component and incorporating a pulley system further reduces the moment of inertia at the robotic arm's end and increases the load-bearing capacity of the elbow joint. Additionally, the shoulder joint employs a direct-drive structure, and control is very simple when three degrees of freedom are satisfied.

[0042] The following, in conjunction with the accompanying drawings, provides further details regarding the wrist joint of the robotic arm, the robotic arm itself, and the robot of this application.

[0043] Figure 1 A front view of a robotic arm according to an embodiment of this application is shown.

[0044] like Figure 1 As shown, the robotic arm 100 includes: a wrist joint 1, an elbow joint 2, a shoulder joint 3, a first robotic arm 11, a second robotic arm 12, and a drive module ( Figure 1 (Not shown in the diagram). The arm between shoulder joint 3 and elbow joint 2 is the first arm, and the arm between elbow joint 2 and wrist joint 1 is the second arm; the drive module is used to drive the wrist joint, the elbow joint, and the shoulder joint.

[0045] Optionally, the first and second arms can be tubular parts, and the wrist joint 1, elbow joint 2, and shoulder joint 3 are connected together by screws.

[0046] Optionally, the drive module may include a first drive module, a second drive module, and a third drive module, which are used to control the wrist joint 1, the elbow joint 2, and the shoulder joint 3, respectively.

[0047] The following is in conjunction with the appendix Figures 2-8 The various parts of the robotic arm are described in detail below. It should be understood that although the details of the wrist joint, elbow joint, and shoulder joint are described separately below, this does not necessarily require that the wrist joint 1, elbow joint 2, and shoulder joint 3 of the robotic arm adopt the following structures simultaneously. Rather, it is possible to adopt only at least one of the wrist joint, elbow joint, and shoulder joint described below, while the remaining joints can adopt the structures of the prior art.

[0048] Figure 2 An overall view of a wrist joint for a robotic arm according to an embodiment of this application is shown. For ease of explanation of the various components of the wrist joint, Figure 3 yes Figure 2 The image shows an exploded view of the wrist joint after it has been horizontally rotated 180° in a horizontal plane.

[0049] like Figure 2 As shown, the wrist joint 200 in the robotic arm (corresponding to...) Figure 1 The wrist joint 1) includes: an end plate 210, a central shaft mounting base 220, a first reel assembly 230 and a second reel assembly 235, and a connecting mechanism 240.

[0050] The end effector 210 is used to fix an end effector. For example, the end effector can be a tool that is connected to the end of a robot's arm to perform a specific task, such as, but not limited to, a robot gripper, a robot welding torch, etc. For example, a robot gripper, a robot welding torch, etc., used to perform a specific task can be fixed to the side of the end effector 210 opposite to the first spool assembly 230 and the second spool assembly 225.

[0051] Combination Figure 3 The central shaft mounting base 220 is connected to the end mounting plate 210. For example, the central shaft mounting base 220 itself is a symmetrical structure, having first opposing sides (a pair of side surfaces) for mounting the first reel assembly 230 and the second reel assembly 235, and second opposing sides (a pair of side surfaces) for connecting the end mounting plate 210, with its axis parallel to the end mounting plate 210. Each of the second opposing sides of the central shaft mounting base can be connected to the end mounting plate 210 via a connecting rod. For example, the first end of each connecting rod is connected to a corresponding side of the second opposing side of the central shaft mounting base, and the second end is connected to the end mounting plate 210.

[0052] The first reel assembly 230 and the second reel assembly 235 are symmetrical with respect to the central shaft fixing seat. They have the same structure, are symmetrically arranged on opposite sides of the central shaft fixing seat and rotate relative to the axis of the central shaft fixing seat, and rotate according to the driving force based on the reel assembly.

[0053] Optionally, each of the first spool assembly 230 and the second spool assembly 235 includes: a spool on which two linear components are wound in opposite directions, and a first end of each linear component is fixed to the spool and a second end is connected to an external drive module for rotation based on a driving force from the external drive module.

[0054] For example, the spool shaft of a spool can be hollow.

[0055] For example, the linear components at the wrist joint can be cords, belts, chains, etc.

[0056] Optionally, to improve control accuracy by controlling the rotational speed of the reel assembly, the reel assembly may also include a speed sensor for detecting the rotational speed of the reels included in the reel assembly, providing this information to a control device. The control device can then provide a corresponding driving force based on the reel assembly (via a drive module) according to the sensed rotational speed. In some examples, the speed sensor may be a photoelectric encoder and is configured to rotate coaxially and at the same speed as the reel shaft.

[0057] Furthermore, when the wrist joint rotates based on the driving force from an external drive module using a linear component, a first drive module for driving the wrist joint can be positioned at one end of the first arm (i.e., the upper arm) near the shoulder joint, and can be used to control the wrist joint by driving the retraction and extension of a first set of linear components (e.g., corresponding to two linear components wound in opposite directions on a spool). For example, each linear component in the first set of linear components can be the same linear component as a corresponding linear component wound on the spool shaft, or each linear component in the first set of linear components can be connected to a corresponding linear component wound on the spool shaft. Optionally, the linear components in the first set of linear components are ropes.

[0058] The connecting mechanism 240 is connected to the first spool assembly 230 and the second spool assembly 235, and is used to connect the first spool assembly 230 and the second spool assembly 235 to the end fixing plate 210 respectively, so that the end fixing plate rotates according to the rotation of the spools included in the first spool assembly and the second spool assembly.

[0059] Optionally, when the reels included in the first reel assembly 230 and the second reel assembly 235 rotate in the same direction of rotation (e.g., both clockwise or counterclockwise), the end plate 210 can rotate in the tilt direction; and when the reels included in the first reel assembly 230 and the second reel assembly 235 rotate in different directions of rotation, the end plate 210 can rotate in the pitch direction.

[0060] For example, when the reel in the first reel assembly 230 rotates clockwise and the reel in the second reel assembly 235 rotates counterclockwise, since both the first reel assembly 230 and the second reel assembly 235 are connected to the end plate via a connecting mechanism, the first reel assembly 230 can provide an upward force to the end plate via the connecting mechanism, and the second reel assembly 235 can also provide an upward force to the end plate via the connecting mechanism. Therefore, at this time, the first reel assembly 230 and the second reel assembly 235 together cause the end plate to be positioned on the first side ( Figure 2 The first spool assembly 230 rotates counterclockwise while the second spool assembly 235 rotates clockwise. Together, the first spool assembly 230 and the second spool assembly 235 provide a downward force to the end plate, causing the end plate to tilt downward on the first side (and tilt upward on the second side opposite to the first side).

[0061] For example, when both the reels in the first reel assembly 230 and the second reel assembly 235 rotate clockwise, since both are connected to the end plate via a connecting mechanism, the first reel assembly 230 can provide an upward force to the end plate via the connecting mechanism, and the second reel assembly 235 can provide a downward force to the end plate via the connecting mechanism. Therefore, the combined torque of these two forces causes the end plate to tilt upward (to the right) on the third side. Conversely, when both the reels in the first reel assembly 230 and the second reel assembly 235 rotate counterclockwise, the first reel assembly 230 and the second reel assembly 235 can cause the end plate to tilt upward (to the left) on the fourth side (opposite to the third side).

[0062] In this way, the end plate of the wrist joint can rotate in the pitch and roll directions, having a two-degree-of-freedom structure and a large range of motion angles, such as a roll angle of -75° to +75° and a pitch angle of -120° to +110°.

[0063] Optionally, the connecting mechanism may include multiple links, with the link sets corresponding to the first reel assembly 230 and the second reel assembly 235 being symmetrical with respect to the central shaft fixing seat. Each link set includes a first link 240-1 (or 245-1 not shown), a second link 240-2 (or 245-2 not shown), and a third link 240-3 (or 245-3 not shown). The first link 240-1 (or 245-1 not shown) is connected to the first reel assembly and the second reel assembly. Between a corresponding spool assembly and a second link in a two-spool assembly; the second link 240-2 (or 245-2 not shown) is connected between the first link 240-1 (or 245-1 not shown) and the third link 240-3 (or 245-3 not shown); and the first end of the third link 240-3 (or 245-3 not shown) is connected to the second link 240-2 (or 245-2 not shown), and the second end is connected to the end fixing plate 210.

[0064] Furthermore, as mentioned above, the connecting rod can be used to connect the central shaft fixing seat to the end fixing plate 210. Therefore, the first ends of the two fourth connecting rods 240-4 or 245-4 (not shown) in the connecting mechanism 240 are symmetrically connected to the remaining opposite sides of the central shaft fixing seat in the direction perpendicular to the end fixing plate 210, except for the opposite sides, and the second ends are respectively connected to the end fixing plate 210.

[0065] Optionally, the first link may include two parts: one part may have a ring structure for fixing to the reel shaft, and the other part is a structure extending from the ring structure for connecting to the second link; the second link may include three parts: the middle part has an angle with the two end parts, and the two end parts are bent to the same side relative to the middle part to facilitate connection with the first and third links respectively; the third link includes two parts: one part is parallel to the end fixing plate for connection to the end fixing plate, and the other part is bent upwards to facilitate connection with the second link respectively. Optionally, a fisheye bearing is provided at the connection between the links to support the rotating mechanical body (link) and / or reduce the coefficient of friction of mechanical load during rotation. Of course, the structure and dimensions of these links can be set according to actual needs, and this application does not limit them.

[0066] Such a connecting mechanism, each reel assembly, end fixing plate, and central shaft fixing seat can be regarded as a spherical linkage mechanism, wherein the movement of the end fixing plate can be simultaneously in the pitch and roll directions and rotate about the same rotation center (the center of the first opposite side line on the axis of the central shaft fixing seat), and thus can be regarded as rotating on a sphere with the center of the sphere being the rotation center.

[0067] Of course, the connecting mechanism is not limited to such Figure 2 and 3 The spherical linkage mechanism shown is an example, but other connecting mechanisms are also possible. For instance, it could be a parallel linkage mechanism, where parallel links are provided for each reel assembly to connect the reel assembly to the end plate, which could also enable the end plate to move simultaneously in both the pitch and roll directions.

[0068] Alternatively, the wrist joint 200 may also include a connector 250 for connecting to the second arm of the robotic arm, and the wrist joint should also be provided with a through hole for transmitting a linear component from the second arm to the reel, so as to drive the reel to rotate according to the driving force of the linear component from the external drive module.

[0069] Additionally, refer to Figures 2-3 The wrist joint may also include: a first side bearing 255, a first washer 260, a first screw 265, a lower fisheye bearing 270, an upper fisheye bearing 275, a second side bearing 280, a second washer 285, a second screw 290, and a large side bearing 295.

[0070] In the context of the embodiments of this application, to avoid obscuring the inventive concept and the key points to be highlighted, detailed descriptions of some components in the wrist joint are omitted, and only the names of these components, such as screws, bearings, etc., are schematically labeled. However, those skilled in the art should understand that in order to implement the above references Figures 2-3 The wrist joint features described may be adapted to include or omit certain related elements, and the shape and size of these elements may be adjusted accordingly to achieve the desired function, without departing from the scope of protection claimed in this application.

[0071] By reference Figures 2-3 The wrist joint described, when used in a robotic arm, reduces the rotational inertia of the robotic arm's end effector because the drive module is not located at the wrist joint. It also employs two pulley assemblies to drive the rotation of the end effector plate, which can rotate in both pitch and tilt directions, making it a two-degree-of-freedom structure with a large range of motion angles.

[0072] The following combination Figures 4-8 Further details about elbow joint 2 are described.

[0073] Figure 4 A front view of an example elbow joint for a robotic arm according to an embodiment of this application is shown. Figure 5 yes Figure 4 The image shows a rear view of the elbow joint. To facilitate explanation of the various components of the elbow joint, Figure 6 It shows Figures 4-5 An exploded view of the elbow joint is shown. Figure 7 and Figure 8 A schematic diagram of the movable pulley block of the pulley mechanism is shown.

[0074] like Figures 4-6 As shown, the elbow joint 400 in the robotic arm (corresponding to...) Figure 1 The wrist joint 1) includes: a first connecting seat 410, a second connecting seat 420 and a pulley mechanism 430.

[0075] The first connecting seat 410 is used to connect with the first machine arm, and the second connecting seat 420 is used to connect with the second machine arm; and the pulley mechanism 430 is connected to the first connecting seat 410 and the second connecting seat 420, and is used to move the second machine arm toward the first machine arm and rotate it away from the first machine arm respectively based on the extension and retraction of the second set of linear components (e.g., two linear components (L1 and L2)), wherein the second set of linear components forms a movable pulley group with a plurality of linear wheels.

[0076] Optionally, when the elbow joint uses a pulley mechanism 430, a second drive module for driving the elbow joint is also located at one end of the first arm near the shoulder joint. It can be integrated with or not integrated with the first drive module, and the second drive module is used to control the elbow joint by driving the extension and retraction of the second set of linear components (two linear components).

[0077] Furthermore, the plurality of pulleys used to form a movable pulley system with the two linear components may include a central large pulley and a plurality of small pulleys. A first portion of the small pulleys, the central large pulley, and the first linear component of the two linear components are used to form a first movable pulley system. A second portion of the small pulleys, the central large pulley, and the second linear component of the two linear components are used to form a second movable pulley system. When the first linear component is tightened, the central large pulley rotates about the pivot, causing the second arm to rotate toward the first arm. When the second linear component is tightened, the central large pulley rotates about the pivot, causing the second arm to rotate away from the first arm.

[0078] For example, the elbow joint may include multiple small spools that can be arranged on the screw, the first connecting seat, the second connecting seat, the central support plate, etc.

[0079] For example, such as Figure 6As shown, the first set of small pulleys (for forming the first movable pulley group) may include a small pulley arranged on the first connecting seat 410, four small pulleys on the screw, and two small pulleys on the central support plate (e.g., fixed carbon plate) 450; and the second set of small pulleys (for forming the second movable pulley group) may include another small pulley arranged on the first connecting seat 410 and two small pulleys arranged on the second connecting seat 420.

[0080] The first linear component in the second group of linear components is wound between the central large reel and the first set of small reels. When the first linear component tightens (correspondingly, the second component also loosens), the central large reel rotates around the pivot, causing the second arm to rotate toward the first arm. The second linear component in the second group of linear components is wound between the central large reel and the second set of small reels. When the second linear component tightens (correspondingly, the first component also loosens), the central large reel rotates around the pivot, causing the second arm to rotate toward the first arm.

[0081] certainly, Figures 4-6 The arrangement of the movable pulley system and the position and number of the small pulleys shown are merely illustrative and can be changed according to actual needs. For example, if a greater load is required, the number of small pulleys can be increased.

[0082] Figure 7 References are shown Figures 4-6 A schematic diagram of the first movable pulley group in the pulley mechanism described in the elbow joint. Figure 7 and Figure 8 For clarity, the first and second connecting seats have been simplified.

[0083] As described above, the first set of small thread pulleys (including one small thread pulley arranged on the first connecting seat 410, four small thread pulleys on the screw, and two small thread pulleys on the central support plate (e.g., a fixed carbon plate) 450), the central large thread pulley, and the first thread-like assembly form the first movable pulley group. Figure 7 A schematic diagram of the first movable pulley system is shown.

[0084] like Figure 7 As shown, a small spool arranged on the first connecting seat 410 is designated as R1, four small spools on the screw are designated as R2-R5, and two small spools on the central support plate (e.g., fixed carbon plate) 450 are designated as R6-R7.

[0085] Figure 7 The view shown is the front view, and Figure 4Corresponding to the front view shown, the first linear assembly L1 extends from the second drive module via the first connecting seat 410 to the first small spool R2 on the screw (winding from the back of the small spool), then winds from the front of the central large spool (i.e., the portion included between the first and second arms when the first and second arms are formed at an angle of 0 to 180°) to the back of the central large spool, passes through the first small spool R6 on the central support plate (e.g., a fixed carbon plate) 450, and then winds from the back of the central large spool to the front of the central large spool. Continue winding the yarn to the second small spool R3 on the screw (winding the yarn from the back of the small spool), then to the small spool R1 on the first connecting seat 410, then to the third small spool R4 on the screw from the small spool R1, then to the back of the central large spool, and then to the second small spool R7 on the central support plate (e.g., fixed carbon plate) 450, and finally to the front of the central large spool and to the fourth small spool R5 on the screw, and finally fixed to a specific position on the first fixed seat.

[0086] exist Figure 7 And the following Figure 8 In the diagram, solid black lines indicate observable windings and components, while dashed black lines indicate obscured windings and components. For example, in a front view, the windings on the back of the central large reel would not be observable.

[0087] Thus, when the second drive module tightens the first linear component, as... Figure 7 As shown in the schematic diagram of the left and right sides, the first arm serves as a reference position. The first linear component, through the first movable pulley group formed above, will cause the central large linear wheel to rotate in the direction of the arrow in the diagram, thereby allowing the second arm to rotate in the direction of the first arm.

[0088] Figure 8 References are shown Figures 4-6 A schematic diagram of the second movable pulley group in the pulley mechanism of the described elbow joint.

[0089] As described above, the second set of small pulleys (including another small pulley arranged on the first connecting seat 410 and two small pulleys arranged on the second connecting seat 420), the central large pulley, and the second linear assembly form the first movable pulley group. Figure 8 A schematic diagram of the second movable pulley system is shown.

[0090] like Figure 8 As shown, the other small spool arranged on the first connecting seat 410 is designated as R8, and the two small spools arranged on the second connecting seat 420 are designated as R9-R10.

[0091] Figure 8 The view shown is the rear view, with Figure 5 Corresponding to the rear view shown, Figure 5 The view in the image shows the housing, and the small reel is fixed to the housing.

[0092] exist Figure 8 In the process, the second linear component L2 is wound from the second drive module via the first connecting seat 410 from the back of the central large spool to the first small spool R9 of the second connecting seat 420, then from the back of the central large spool to the small spool R8 on the first connecting seat 410, then from the back of the central large spool to the second small spool R10 of the second connecting seat 420, and finally fixed to a specific position on the first fixed seat after being wound on the small spool R10.

[0093] Thus, as Figure 7 As shown in the left and right side diagrams, with the first arm as a reference position, when the second drive module tightens the first linear component, the second linear component will cause the central large linear wheel to rotate in the direction of the arrow in the diagram through the second movable pulley group formed above, thereby allowing the second arm to rotate away from the first arm.

[0094] At this time, Figure 7 and Figure 8 In the winding structure shown, the states of the first and second wire components are opposite; that is, when the first wire component is tightened, the second wire component is correspondingly loosened; and when the second wire component is tightened, the first wire component is correspondingly loosened.

[0095] certainly, Figure 7 and Figure 8 The above is just an example. Depending on the actual needs, the specific way of setting up the movable pulley system can be set up in other ways. Different combinations of pulleys can be used to form different types of movable pulley systems. Furthermore, the movable pulley system can include more or fewer pulleys to match different load requirements.

[0096] Additionally, refer to Figures 4-6 The pulley mechanism of the wrist joint may also include components such as a connecting shaft 430-1, a snap ring 430-2, and a side bearing 430-3, for connecting the first connecting seat and the second connecting seat, and for fixing the central large pulley to the second connecting seat, or to the first connecting seat, or to the first machine arm, or to the second machine arm, etc.

[0097] Optionally, the second connecting seat (second arm (forearm) side) and the first connecting seat (first arm (upper arm) side) can be limited by a connecting shaft, a retaining bearing and a snap ring to ensure rotational freedom between the first arm and the second arm.

[0098] In addition, as mentioned above, since the wire components required for the wrist joint also pass through the elbow joint, wire grooves can be provided on both sides of the central large wire reel to transmit the wire components for the wrist joint.

[0099] In the context of the embodiments of this application, in order to avoid obscuring the inventive concept and the key points to be highlighted, detailed descriptions of certain elements or their components in the elbow joint have been omitted. However, those skilled in the art should understand that, in order to implement the above-referenced... Figures 4-8 The described elbow joint features may be adapted to include or omit certain related elements, and the shape and size of these elements may be adjusted accordingly to achieve the desired function, while still remaining within the scope of protection claimed in this application.

[0100] By reference Figures 4-8 The described elbow joint, when used in a robotic arm, reduces the rotational inertia of the robotic arm's end effector because the drive module is not located at the elbow joint. Furthermore, the use of a moving pulley system composed of multiple spools improves the robotic arm's load-bearing capacity and provides a large range of motion angles, such as up to 150°.

[0101] In some examples, as described above, at least one of the first drive module or the second drive module may be disposed near the shoulder joint of the first arm, thus providing a predetermined space in the first arm to accommodate at least one of the first drive module or the second drive module. Furthermore, for driving... Figures 2-4 The first drive module of the wrist joint shown may include two thread drive sub-modules corresponding to the first thread pulley assembly and the second thread pulley assembly respectively, and the second drive module for driving the elbow joint includes one thread drive sub-module.

[0102] Figure 9 A cross-sectional schematic diagram of the first arm at a predetermined space where the first drive module or the second drive module is placed is shown.

[0103] Figure 9 A line wheel drive submodule within a predetermined space is shown, and will be referenced later. Figure 10 The shoulder joint is shown together with the description. (See example.) Figure 9 As shown, the thread drive submodule includes a thread drive motor 910 and a thread drive shaft 920. Two thread-like components can be wound on the thread drive shaft in opposite directions. The rotation of the thread drive shaft is driven by the corresponding drive motor, which is used to drive the winding and unwinding of each thread-like component.

[0104] Although Figure 9 The three possible wheel drive submodules are not shown, but it is easy to understand that the other two wheel drive submodules are based on the same principle.

[0105] For example, when two linear components on the spool drive shaft in the spool drive submodule also serve as linear components wound in opposite directions on the spool of the wrist joint, one end of each of the two linear components is fixed to and wound on the spool shaft of the wrist joint, and the other end is fixed to and wound on the spool drive shaft in the spool drive submodule.

[0106] For example, when the two linear components on the linear drive shaft in the linear drive submodule are not linear components on the linear wheel of the wrist joint, one end of each of the two linear components will be connected to and wound around another linear component on and around the linear drive shaft of the wrist joint, and the other end will be fixed to and wound around the linear drive shaft in the linear drive submodule.

[0107] For example, when driving the elbow joint, one end of each of the two linear components on the spool drive shaft in the spool drive submodule can be fixed at a specific position in the first connecting seat in the elbow joint, and a movable pulley group is formed by multiple small spools and a central large spool in the manner described above, while the other end is fixed to the spool drive shaft in the spool drive submodule and wound on the spool drive shaft.

[0108] In addition, Figure 9 In the thread drive submodule, one end of the thread drive shaft 920 is directly connected to the thread drive motor 910 to control its rotation, and the other end is connected to the bearing 930 and the bearing cover plate. Figure 10 The 1070 in the middle is fixed on the first arm.

[0109] In this way, a relatively simple wheel drive submodule set at one end of the first arm can be used to drive at least one of the wrist and elbow joints, and the rotational inertia of the end of the robotic arm can be reduced by reducing the weight of at least one of the wrist and elbow joints.

[0110] The following combination Figure 10 More details about shoulder joint 3 are described.

[0111] Figure 10 A view of an example shoulder joint for a robotic arm according to an embodiment of this application is shown.

[0112] like Figure 10 As shown, shoulder joint 1000 (corresponding to) Figure 1 The shoulder joint 3) needs to achieve three degrees of freedom, which can be driven by three driving sub-modules respectively. The shoulder joint can be directly driven by the third driving module, that is, it can be directly constructed by the three driving sub-modules that can achieve three degrees of freedom included in the third driving module. Therefore, in this case, the shoulder joint can also be considered to be implemented by the third driving module.

[0113] Optionally, the third drive module may include a first drive submodule 1010, a second drive submodule 1020, and a third drive submodule 1030, which are arranged perpendicularly to each other and correspond to the three degrees of freedom. The first drive submodule 1010 is connected to the end of the first arm 11 near the shoulder joint. The second drive submodule 1020 is connected to the first arm via a first drive connector C1 (e.g., via a connector or directly). The third drive submodule 1030 is connected to the second drive submodule 1020 via a second drive connector C2.

[0114] Optionally, each of the first drive submodule 1010, the second drive submodule 1020, and the third drive submodule 1030 may include a drive motor and an electric shaft corresponding to the drive motor. The first end of the first drive connector C1 is connected to the electric shaft corresponding to the drive motor of the first drive submodule 1010, and the second end is connected to the electric shaft corresponding to the drive motor of the second drive submodule 1020. The first end of the second drive connector C2 is connected to the electric shaft corresponding to the drive motor of the second drive submodule 1020, and the second end is connected to the electric shaft corresponding to the drive motor of the third drive submodule 1030.

[0115] For example, both the first drive connector and the second drive connector are right-angled connectors. When the electric shaft corresponding to the drive motor of the first drive submodule 1010 rotates, since the first drive submodule 1010 (the electric shaft corresponding to the drive motor) is connected to the first machine arm 11, the first machine arm will rotate according to the rotation direction of the electric shaft corresponding to the drive motor of the first drive submodule 1010. When the electric shaft in the second drive submodule rotates, due to the force transmission of the first drive connector C1, the electric shaft will drive the first machine arm to rotate according to the rotation direction of the electric shaft corresponding to the drive motor of the second drive submodule 1020. And when the electric shaft corresponding to the drive motor of the third drive submodule 1030 rotates, due to the force transmission of the first drive connector C1 and the second drive connector C2, the electric shaft will drive the first machine arm to rotate according to the rotation direction of the electric shaft corresponding to the drive motor of the third drive submodule 1030.

[0116] Optionally, a connector 1050 may be provided between the first drive submodule 1010 and the first arm 11 to facilitate the drive motor in the first drive submodule to drive the first arm. Each drive submodule may also include a mounting base 1060, which is disposed on the outer periphery and / or upper surface of the drive motor to fix the drive motor into the mounting base to prevent wear.

[0117] Therefore, refer to Figure 10The described shoulder joint structure can achieve three degrees of freedom by direct drive of a drive motor, forming a shoulder joint that can rotate 360° in each of the three degrees of freedom. Therefore, the structural design and control process are relatively simple.

[0118] According to another aspect of this application, a robot is also disclosed, wherein the robot has a robotic arm, the robotic arm being capable of having the features described in the preceding reference. Figures 2-3 Description of the wrist joint, reference Figures 4-9 Description of the elbow joint and reference Figure 10 A robotic arm describing at least one of the shoulder joints.

[0119] Alternatively, the robot may be configured with associated processing devices, located locally or externally to the robot body, for providing drive control commands to the drive unit in the robotic arm.

[0120] The processing device may include a processor (e.g., a central processing unit (CPU), a digital signal processing circuit (DSP), an application-specific integrated circuit (ASIC), etc.) that can parse various instructions within the robot (including drive control instructions for the robotic arm) and process various data from the robot. Furthermore, the processing device may also include memory for storing programs and data, for example, it may be stored in a computer-readable storage medium, which may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, etc. It is understood that the memory here may include both the robot's built-in memory and, of course, extended memory supported by the robot.

[0121] This application uses specific terms to describe embodiments of the application. Terms such as "first / second embodiment," "an embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the application. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Furthermore, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0122] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in a common dictionary shall be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as being interpreted in an idealized or highly formalized sense, unless expressly defined herein.

[0123] The foregoing description is illustrative of the invention and should not be construed as limiting it. Although several exemplary embodiments of the invention have been described, those skilled in the art will readily understand that many modifications can be made to the exemplary embodiments without departing from the novel teachings and advantages of the invention. Therefore, all such modifications are intended to be included within the scope of the invention as defined in the claims. It should be understood that the foregoing description is illustrative of the invention and should not be construed as limiting it to the specific embodiments disclosed, and modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the appended claims. The invention is defined by the claims and their equivalents.

Claims

1. A wrist joint in a robotic arm, comprising: End-effector mounting plate, used to secure the end effector; A central shaft fixing seat is connected to the end fixing plate; The first and second thread pulley assemblies are symmetrically arranged on the first opposite sides of the central shaft fixing seat and rotate relative to the axis of the central shaft fixing seat, and rotate according to the driving force based on the thread assembly. as well as A connecting mechanism, connected to the first and second thread reel assemblies, is used to connect the first and second thread reel assemblies to the end fixing plate respectively, such that the end fixing plate rotates according to the rotation of the first and second thread reel assemblies. Each of the first reel assembly and the second reel assembly includes: A spool has two thread-like components wound in opposite directions on its spool shaft. The first end of each thread-like component is fixed to the spool shaft, and the second end is connected to an external drive module for rotating according to the driving force from the external drive module based on the thread-like components. The external drive module is located at the upper end of the robotic arm and is used to drive the spool shaft to rotate, causing the two thread-like components wound in opposite directions to produce a contraction and expansion motion, thereby driving the spool to rotate. The connecting mechanism includes multiple links, and the rotation of the spools in the first spool assembly and the second spool assembly is converted into the rotation of the end fixing plate relative to the central shaft fixing seat in two degrees of freedom: pitch and tilt, via the connecting mechanism. In this connection mechanism, the linkage sets in the connecting mechanisms corresponding to the first and second reel assemblies are symmetrical with respect to the central shaft fixing seat, and each linkage set includes a first linkage, a second linkage, and a third linkage, wherein: the first linkage connects a corresponding reel assembly and the second linkage; the second linkage connects the first linkage and the third linkage; the third linkage connects the second linkage and the end fixing plate; the first ends of the two fourth linkages in the connecting mechanism are respectively connected to the second opposite sides of the central shaft fixing seat in a direction perpendicular to the end fixing plate, excluding the first opposite sides, and the second ends are respectively connected to the end fixing plate; The first connecting rod comprises two parts: one part has a ring structure for fixing to the reel shaft, and the other part is a structure extending from the ring structure for connecting to the second connecting rod; the second connecting rod comprises three parts: the middle part has an included angle with the two end parts, and the two end parts are bent toward the same side relative to the middle part for connecting to the first connecting rod and the third connecting rod respectively; the third connecting rod comprises two parts: one part is parallel to the end fixing plate for connecting to the end fixing plate, and the other part is bent upwards for connecting to the second connecting rod.

2. The wrist joint according to claim 1, wherein, When both the reels in the first reel assembly and the reels in the second reel assembly rotate in the same direction of rotation, the end fixing plate can rotate in the lateral tilt direction; and When the spools in the first spool assembly and the spools in the second spool assembly rotate in different directions, the end fixing plate can rotate in the pitch direction.

3. The wrist joint according to claim 1, wherein, Each of the first reel assembly and the second reel assembly further includes: A speed sensor, configured in association with the reel, is used to detect the speed of the reel in order to provide information to the processing device.

4. A robotic arm, comprising: Wrist joint, elbow joint and shoulder joint, wherein the wrist joint is the wrist joint according to any one of claims 1-3; The first arm and the second arm, wherein the arm between the shoulder joint and the elbow joint is the first arm, and the arm between the elbow joint and the wrist joint is the second arm; A drive module for driving the wrist joint, the elbow joint, and the shoulder joint.

5. The robotic arm according to claim 4, wherein, The driving module includes: A first drive module is disposed at one end of the first arm near the shoulder joint and is used to control the wrist joint by driving the extension and retraction of a first set of linear components. A second drive module is used to drive the elbow joint; and The third drive module is integrated with the shoulder joint and is used to drive the shoulder joint.

6. The robotic arm according to claim 5, wherein, The elbow joint includes: A first connecting seat is used to connect to the first machine arm; The second connecting seat is used to connect to the second machine arm; A pulley mechanism, connected to the first connecting seat and the second connecting seat, is used to move the second arm toward the first arm and rotate it away from the first arm, respectively, based on the retraction and extension of the second set of linear components. The second group of linear components forms a movable pulley group with multiple linear wheels.

7. The robotic arm according to claim 6, wherein, The plurality of spools includes a central large spool and a plurality of smaller spools. The first group of small spools, the central large spool, and the first linear assembly in the second group of linear assemblies are used to form a first movable pulley group. The second small spool among the plurality of small spools, the central large spool, and the second linear assembly in the second group of linear assemblies are used to form a second movable pulley group. Specifically, when the first linear component is tightened, the central large threaded wheel rotates around the pivot, causing the second arm to rotate toward the first arm; and when the second linear component is tightened, the central large threaded wheel rotates around the pivot, causing the second arm to rotate away from the first arm.

8. The robotic arm according to claim 6, wherein, The second drive module is located at one end of the first arm near the shoulder joint, and may be integrated with or not integrated with the first drive module.

9. The robotic arm according to claim 7 or 8, wherein, The first drive module includes two thread drive sub-modules corresponding to the first thread pulley assembly and the second thread pulley assembly, respectively, and the second drive module includes one thread drive sub-module. Each threaded drive submodule includes a threaded drive motor and a threaded drive shaft. Two threaded components from the first group of threaded assemblies or the second group of threaded assemblies are wound in opposite directions on the corresponding threaded drive shaft. Each thread drive submodule includes a thread drive shaft driven by a corresponding thread drive motor, used to drive the tightening of two thread components in the first group of thread components or the second group of thread components.

10. The robotic arm according to claim 9, wherein, The first end of each of the first group of linear components is fixed to the corresponding spool drive shaft, and the second end is wound around the spool shaft of one of the first and second spool components of the wrist joint via the elbow joint and then fixed to the spool shaft.

11. The robotic arm according to claim 7, wherein, The shoulder joint is directly driven by the third drive module. The third drive module includes a first drive submodule, a second drive submodule, and a third drive submodule, which are arranged perpendicularly to each other and correspond to the three degrees of freedom. The first drive submodule is connected to the end of the first arm near the shoulder joint; the second drive submodule is connected to the first arm via a first drive connector, and the third drive submodule is connected to the second drive submodule via a second drive connector.

12. The robotic arm according to claim 11, wherein, Each of the first drive submodule, the second drive submodule, and the third drive submodule includes a drive motor and an electric shaft corresponding to the drive motor. The first end of the first drive connector is connected to the electric shaft corresponding to the drive motor of the first drive submodule, and the second end is connected to the electric shaft corresponding to the drive motor of the second drive submodule. The first end of the second drive connector is connected to the electric shaft corresponding to the drive motor of the second drive submodule, and the second end is connected to the electric shaft corresponding to the drive motor of the third drive submodule.

13. A robot comprising the robotic arm as described in any one of claims 4 to 12.

Images