Rope-driven test system for variable-stiffness mechanical arm and variable-stiffness gripper

Abstract

A rope-driven test system for a variable-rigidity mechanical arm and a variable-rigidity gripper comprises a two-degree-of-freedom passive motion part, a three-degree-of-freedom active motion part, a pure-rigidity mechanical arm, a flexible joint, the variable-rigidity mechanical arm, the variable-rigidity gripper and a frame. The two-degree-of-freedom passive motion part allows manual posture adjustment, and the three-degree-of-freedom active motion part is driven by a motor to achieve accurate operation. Pure rigid robotic arms provide high stiffness operation, and flexible joints and variable stiffness robotic arms allow for dynamic stiffness adjustment to accommodate different tasks. The variable-stiffness gripper is used as an end effector and is in direct contact with an object. The whole system is installed on a frame, structural stability and modular design are achieved, and the performance of the mechanical arm and the performance of the gripper can be comprehensively evaluated. The rope-driven testing system is comprehensive in function, flexible in operation and convenient and fast to maintain, the performance of the variable-stiffness mechanical arm and the performance of the gripper can be effectively tested and verified, and important technical support is provided for practical application.

Description

Technical Field

[0001] The invention relates to robot technology, in particular to a rope-driven testing system for a variable-rigidity mechanical arm and a variable-rigidity gripper. Background Art

[0002] With the rapid development of robotics, robots are increasingly used in industry, medicine, services and other fields. Traditional robots generally have a rigid structure, which makes them excel in performing high-precision, high-rigidity tasks. However, rigid robots have limitations in certain application scenarios, especially in tasks that require complex interactions with flexible materials or irregular objects. In order to meet these challenges, variable stiffness technology has emerged.

[0003] The variable stiffness manipulator and variable stiffness gripper can dynamically adjust their stiffness according to the task requirements. This adjustable stiffness feature can not only improve the robot's operational flexibility, but also effectively enhance its adaptability in complex environments. For example, when it is necessary to operate through narrow spaces or flexible materials, the variable stiffness manipulator can soften its structure to avoid collision or damage to the target object; when it is necessary to perform high-precision operations or fix the target, the manipulator can quickly increase its stiffness to ensure the stability and accuracy of the operation.

[0004] At present, variable stiffness technology still faces many challenges in practical applications, including how to achieve accurate control and testing of variable stiffness manipulators and grippers. In order to test and verify the performance of such variable stiffness systems, it is particularly important to develop a dedicated test platform. Most existing test platforms are designed for rigid structures and lack support for variable stiffness systems.

[0005] There is a variable stiffness rigid-flexible coupling manipulator, which combines the high flexibility of the flexible manipulator and the high precision of the rigid manipulator, and realizes dynamic adjustment of stiffness by cooperating with the flexible bending arm and the rigid adjustment component. A rigidity adjustment cavity is provided in the flexible bending arm, and the rigidity of the bending arm is controlled by adjusting the insertion depth of the rigidity adjustment rod. This design enables the manipulator to switch between softness and rigidity, so as to adapt to different task requirements. The manipulator is also equipped with multiple sensors, which perform negative feedback adjustment by real-time monitoring of the bending degree of the flexible manipulator to ensure the accuracy and stability of the manipulator when performing tasks. Its disadvantages are: 1. Structural complexity and maintenance cost: The manipulator relies on complex rigidity adjustment components and multi-sensor systems, which not only increases the structural complexity of the manipulator, but also may lead to an increase in manufacturing and maintenance costs. 2. Response speed and control difficulty: The system needs to rely on multi-sensor feedback and pneumatic drive to achieve stiffness adjustment, which may limit the response speed of the system and increase the difficulty of control. Especially in the face of rapidly changing task environments, such a system may find it difficult to maintain stable performance. 3. Smoothness of switching between flexibility and rigidity: In this design, the stiffness adjustment is achieved by adjusting the insertion depth of the rigidity adjustment rod. This method may result in an unsmooth switching process between flexibility and rigidity, affecting the operational continuity of the robotic arm and the operator experience.

[0006] There is another hybrid-driven foldable space soft robot arm, which adopts a hybrid drive mode combining rope drive and inflation drive. The robot arm is designed as a multi-stage structure, which is composed of multiple modular structural units in series. Each modular structural unit is connected by a central airbag and a driving rope is connected to the partition, and the driving rope is controlled by a driving motor. The central airbag is used to realize the inflation drive of the robot arm, while the driving rope provides structural support and motion control of the robot arm. During the working process, the robot arm is unfolded by inflation and folded by tightening the rope, so as to have variable stiffness and foldable performance. This design is particularly suitable for space mission applications, which can significantly reduce the volume when stored and provide sufficient stiffness and flexibility when unfolded. Its disadvantages are: 1. Complexity and stability of the drive mode: This hybrid drive mode involves dual control of airbags and ropes, which makes the control and coordination of the entire system more complicated. In particular, precise synchronization needs to be maintained between airbag inflation and rope tightening, which may cause stability problems when the system responds to needs quickly. 2. Limitations of applicable environments: The hybrid drive manipulator is designed mainly for space missions and has the advantage of operating in a vacuum environment, but its application in ground or industrial environments may be limited, especially when facing non-standard or dynamic environments, the system's adaptability and flexibility may be insufficient. 3. Maintenance and operational complexity: The system's multi-segment structure and complex drive mode make maintenance and operation more complicated, especially when the airbag or rope system needs to be maintained, the difficulty and cost of operation will increase.

[0007] It should be noted that the information disclosed in the above background technology section is only used for understanding the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention

[0008] The main purpose of the present invention is to overcome the defects existing in the above-mentioned background technology and provide a rope-driven testing system for a variable-stiffness mechanical arm and a variable-stiffness gripper.

[0009] To achieve the above object, the present invention adopts the following technical solutions:

[0010] A rope-driven testing system for a variable-stiffness manipulator and a variable-stiffness gripper, comprising:

[0011] Two-DOF passive motion part, used to manually adjust the posture of the robot arm and gripper;

[0012] The three-degree-of-freedom active motion part cooperates with the two-degree-of-freedom passive motion part to achieve precise operation of the robotic arm through motor drive;

[0013] A purely rigid robotic arm, located below the three-degree-of-freedom active motion part and connected to the flexible joint, is used to provide high rigidity and high precision of the operation;

[0014] A flexible joint connects the purely rigid robotic arm and the variable stiffness robotic arm, allowing the robotic arm part to have a certain degree of flexibility during operation;

[0015] A variable stiffness manipulator, located below the flexible joint and connected to a variable stiffness gripper, capable of dynamically adjusting its stiffness according to task requirements;

[0016] The variable stiffness gripper is located at the bottom of the system and is connected to the variable stiffness robotic arm for direct contact and manipulation of objects.

[0017] The frame supports the structure of the entire system and is used to install the two-degree-of-freedom passive motion part, the three-degree-of-freedom active motion part, the pure rigid robotic arm, the flexible joint, the variable stiffness robotic arm and the variable stiffness gripper, providing structural stability and modular design.

[0018] Furthermore, the two-degree-of-freedom passive motion part includes: a connecting plate, which is connected to the frame by screws; a retaining main board and a retaining bracket, which are used for stable support and are connected to each other by mortise and tenon structures and vertical plate connectors; a reinforced aluminum tube, which is connected to the retaining main board by an adapter, provides a first passive degree of freedom, and allows rotation adjustment around a certain axis; a fixed bracket, which is fixed between the frame and the retaining main board, and is used to fix the first passive degree of freedom, which can be released when removed; an adapter, which allows rotation adjustment in a direction perpendicular to the first passive degree of freedom, is connected to the connecting base plate by a bearing and a rotating shaft, and provides a second passive degree of freedom.

[0019] Furthermore, the three-degree-of-freedom active motion part includes: a Yaw-axis motor drive, which is connected to the base plate through a motor fixing bracket and an aluminum column, and outputs a rotational torque to the inner ring of a cross-roller bearing to achieve precise and stable rotation of the system in the Yaw-axis direction; the rotation is converted into the degree of freedom of a linear pull rope, which is driven by another two motors, which are installed on the base plate through a motor fixing bracket, connected to a motor winding drum to drive a wire rope, and transmit power to the robotic arm through an intermediate pulley to achieve precise operation of the robotic arm.

[0020] Furthermore, the flexible joint is controlled by pulling or releasing the wire rope through the rotation of the motor.

[0021] Furthermore, the flexible joint includes four steel cables, and one motor drives two steel cables simultaneously, so that the joint can move flexibly in different directions.

[0022] Furthermore, it also includes: a copper column, which is used to connect the purely rigid robotic arm and the connecting print to provide structural stability; a universal joint, which is used to connect to the connecting print below, with a threaded shaft embedded in the middle for fixation, a spring in the middle for passing the wire rope, and pre-tightening the wire rope through the pre-tightening print, allowing the connected joint to rotate freely in different directions.

[0023] Furthermore, it also includes a raising plate for raising the fixing frame of the pulley so that the steel wire ropes are staggered to avoid mutual interference.

[0024] Furthermore, the variable stiffness robotic arm is a mechanism capable of adjusting mechanical stiffness so as to dynamically adjust its own stiffness according to task requirements.

[0025] Furthermore, the variable stiffness gripper serves as an end effector and changes its stiffness through an internal adjustment mechanism such as vacuuming or inflation, so as to increase the stiffness to firmly grasp the object when in contact with the object, and reduce the stiffness when not in contact with the object or when flexible adjustment is required.

[0026] Furthermore, the frame is the aluminum profile frame.

[0027] The present invention has the following beneficial effects:

[0028] The rope-driven test system of the present invention provides an innovative test platform for variable stiffness manipulators and variable stiffness grippers, and its main technical advantage lies in its high flexibility and adaptability. By combining rope-driven technology and multi-degree-of-freedom control, the system can simulate and test various complex operation tasks, thereby providing important technical support and reference for the practical application of variable stiffness technology. The design of the system allows the manipulator and gripper to be dynamically adjusted under different stiffness conditions, so that they can perform precise operations in a variety of environments while maintaining the safety and flexibility of operation. In addition, the manual adjustment function of the system enables the operator to directly control the position and posture of the manipulator and gripper, which is convenient for instant adjustment during the test process. The modular design makes the entire system easy to assemble, debug and maintain, and can be adjusted and expanded according to different test requirements. The design of the system not only simplifies the control process and reduces potential failure points, but also improves the overall stability and reliability, and reduces the manufacturing and maintenance costs. Therefore, the system of the present invention is particularly suitable for complex and dynamic applications on the ground or in industrial environments, and can provide comprehensive performance evaluation and data support for future technological advances and practical applications.

[0029] Compared with the aforementioned prior art 1, the advantages of the present invention are at least as follows: the rope drive technology adopted is relatively simple, maintenance is more convenient, and the complexity and cost of the overall system are reduced; the system of the present invention can respond to operational requirements more quickly through direct rope drive and mechanical structure adjustment, and is also more intuitive and easy to implement in terms of control; the system of the present invention can achieve a smoother transition through rope drive and variable stiffness control, ensuring the continuity and stability of operation.

[0030] Compared with the above-mentioned prior art 2, the advantages of the present invention are at least as follows: the system is driven only by ropes, which simplifies the control process, reduces potential failure points, and improves the overall stability and reliability of the system. The system design of the present invention is more suitable for various complex and dynamic ground environments, especially for ground applications. The system structure of the present invention is relatively simple, maintenance is more convenient, operation is more intuitive, and it is suitable for long-term use and rapid deployment.

[0031] Other beneficial effects of the embodiments of the present invention will be further described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the overall structure of a rope drive test system according to an embodiment of the present invention.

[0033] Figure 2 FIG. 4 is a schematic diagram of a two-degree-of-freedom passive motion portion of an embodiment of the present invention.

[0034] Figure 3 It is an exploded view of the two-degree-of-freedom passive motion part of an embodiment of the present invention.

[0035] Figure 4 Schematic diagram of the active axis, pure rigid robot arm and flexible joint of the three-degree-of-freedom active motion part of an embodiment of the present invention.

[0036] Figure 5 It is an exploded diagram of the active axis, pure rigid robot arm and flexible joint of the three-degree-of-freedom active motion part of an embodiment of the present invention.

[0037] Figure 6 It is a partial schematic diagram of a flexible joint according to an embodiment of the present invention.

[0038] Figure 7 This is a wiring configuration diagram of a flexible joint according to an embodiment of the present invention.

[0039] Figure 8 Schematic diagram of the variable stiffness system arrangement of an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The following is a detailed description of the embodiments of the present invention. It should be emphasized that the following description is only exemplary and is not intended to limit the scope and application of the present invention.

[0041] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, connection can be used for fixing as well as for coupling or communication.

[0042] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0043] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0044] See also Figures 1 to 8The embodiment of the present invention provides a rope-driven testing system for a variable-rigidity manipulator 6 and a variable-rigidity gripper 7, comprising: a two-degree-of-freedom passive motion part 2, for manually adjusting the posture of the manipulator and the gripper; a three-degree-of-freedom active motion part 3, which cooperates with the two-degree-of-freedom passive motion part 2 to achieve precise operation of the manipulator through motor drive; a pure rigid manipulator 4, located below the three-degree-of-freedom active motion part 3, connected to the top of a flexible joint 5, for providing high rigidity and high precision of operation; a flexible joint 5, connected between the pure rigid manipulator 4 and the variable-rigidity manipulator 6, allowing the manipulator The part has a certain flexibility in operation; the variable stiffness manipulator arm 6 is located below the flexible joint 5 and is connected to the variable stiffness gripper 7, and can dynamically adjust its own stiffness according to task requirements; the variable stiffness gripper 7 is located at the bottom of the system and is connected to the variable stiffness manipulator arm 6 for directly contacting and operating with objects; the frame 1, which can be an aluminum profile frame, supports the structure of the entire system, and installs the two-degree-of-freedom passive motion part 2, the three-degree-of-freedom active motion part 3, the pure rigid manipulator arm 4, the flexible joint 5, the variable stiffness manipulator arm 6 and the variable stiffness gripper 7, to provide structural stability and modular design.

[0045] See also Figure 2 and Figure 3 In a preferred embodiment, the two-degree-of-freedom passive motion part 2 includes: a connecting plate 8, which is connected to the frame 1 by screws; a retaining main board 9 and a retaining bracket 10, which are used for stable support and are interconnected by a mortise and tenon structure and a vertical plate connector 14 to ensure the stability of the structure during adjustment; a reinforcing aluminum tube 12, which is connected to the retaining main board 9 by an adapter 13, provides a first passive degree of freedom, and allows rotation adjustment around a certain axis; a fixing bracket 11, which is fixed between the frame 1 and the retaining main board 9, and is used to fix the first passive degree of freedom, which can be released when removed; an adapter 15, which allows rotation adjustment in a direction perpendicular to the first passive degree of freedom, and is connected to the connecting base plate 19 by a sleeve 16, a bearing 17, and a rotating shaft 18, to provide a second passive degree of freedom.

[0046] See also Figure 4 and Figure 5 In a preferred embodiment, the three-degree-of-freedom active motion part 3 includes: a Yaw axis motor 20 driving, which is connected to the base plate 23 through a motor fixing frame 21 and an aluminum column 22, and outputs a rotation torque to the inner ring of a cross roller bearing 37 to achieve accurate and stable rotation of the system in the Yaw axis direction; the rotation is converted into the degree of freedom of a linear pull rope, which is driven by another two motors 25, which are installed on another base plate 24 through a motor fixing seat 26, connected to a motor winding disk 27 to drive a steel wire rope 28, and transmits power to the robot arm through an intermediate pulley to achieve accurate operation of the robot arm. The motor can be equipped with a motor speed regulator 39.

[0047] See also Figures 4 to 7 , the flexible joint 5 is controlled by pulling or releasing the wire rope 28 through the rotation of the motor. In a preferred embodiment, the flexible joint 5 includes four wire ropes 28, and one motor drives two wire ropes 28 at the same time, so that the joint can move flexibly in different directions. In a preferred embodiment, the system also includes: a copper column for connecting the purely rigid robotic arm 4 and the connecting print 30 to provide structural stability; a universal joint 31 for connecting with the lower connecting print 30, with a threaded shaft 32 embedded in the middle for fixing, a spring 38 in the middle for passing the wire rope 28, and pre-tightening the wire rope 28 through the pre-tightening print 33, allowing the connected joint to rotate freely in different directions. The system also includes a padding plate 34 for padding the pulley fixing frame 29 so that the wire ropes 28 are staggered to avoid mutual interference.

[0048] See also Figure 8 The variable stiffness manipulator 6 is a mechanism that can adjust the mechanical stiffness to dynamically adjust its stiffness according to the task requirements. The variable stiffness gripper 7, as the end effector, changes its stiffness through an internal adjustment mechanism such as air extraction or inflation, so as to increase the stiffness to firmly grasp the object when it contacts the object, and reduce the stiffness when it does not contact the object or needs flexible adjustment.

[0049] The present invention provides a rope-driven test system that can effectively test the performance of variable-stiffness manipulators and variable-stiffness grippers. The system can simulate and test various complex operating tasks by combining rope drive and multi-degree-of-freedom control, providing a fully functional and flexible platform for testing variable-stiffness technology, and can effectively test and verify the performance of variable-stiffness manipulators and grippers in various tasks and environments. Through this system, key performance indicators such as stiffness adjustment, operational flexibility, and load capacity of manipulators and grippers can be comprehensively evaluated, thereby providing important technical support for practical applications.

[0050] The characteristics of the present invention are as follows: 1. Multi-degree-of-freedom operation: The test system of the present invention has up to three degrees of freedom driven by motors and two degrees of freedom for manual passive adjustment, which can realize complex spatial motion and flexibly respond to various test requirements. 2. Rope drive system: The rope drive technology is adopted to pull and control the flexible joints through dual motors to realize the precise operation of the manipulator and gripper. This design can not only simulate various complex operation tasks, but also reduce the rigidity of the mechanical system, thereby improving the safety and flexibility of the test. 3. Testing under variable stiffness conditions: The system supports dynamic adjustment of the stiffness of the manipulator and gripper, so that the manipulator and gripper can still perform operations under different stiffness conditions. This feature enables the system to simulate and test the performance of the manipulator and gripper under different stiffness, providing data support for practical applications. 4. Manual adjustment function: The two axes at the top can be manually and passively adjusted, so that the operator can directly control the position and posture of the manipulator and gripper. This function facilitates the operator to make instant adjustments during the test, especially in scenarios where manual operation or fine adjustment is required. 5. Modular design: The entire system adopts a modular design, which is easy to assemble, debug and maintain. The frame structure built with profiles is light and highly adaptable, and can be adjusted and expanded according to different test requirements. 6. Adapt to a variety of test tasks: The system can flexibly respond to various complex environments and task requirements, including flexible operation, narrow space operation, grasping test of different objects, etc., providing strong support for the practical application of variable stiffness technology.

[0051] The specific embodiments of the present invention are further described below.

[0052] Figure 1 The overall structure diagram of the rope drive test system of the embodiment of the present invention is shown in FIG. The rope drive test system comprises three major parts: a passive motion part, an active motion part and a variable stiffness system, and specifically comprises a two-degree-of-freedom passive motion part 2, a three-degree-of-freedom active motion part 3, a pure rigid manipulator 4, a flexible joint 5, a variable stiffness manipulator 6, a variable stiffness gripper 7, and an aluminum profile frame.

[0053] The two-degree-of-freedom passive motion part 2 is located at the top of the system. This part provides two degrees of freedom of passive motion. These two degrees of freedom can be adjusted manually, allowing the operator to quickly adjust the posture of the robot arm and gripper without relying on motor drive. This design is particularly suitable for operating scenarios that require frequent posture changes or fine adjustments, such as manual debugging and calibration tasks.

[0054] The three-degree-of-freedom active motion part 3 is located below the two-degree-of-freedom passive motion part 2. This part provides three-degree-of-freedom active motion capabilities, including the rotation of the top YAW axis and the two degrees of freedom of rotation converted into linear pull ropes. These degrees of freedom are driven by motors and can be precisely operated by the control system. Their main function is to allow the robot arm to perform complex tasks within a wider operating range and to automatically adjust the position and posture according to the task requirements. And this part is the core driving part of the entire system, ensuring high-precision motion control of the robot arm and gripper.

[0055] The purely rigid manipulator 4 is located below the active motion part and connected to the top of the flexible joint 5. This part is made of purely rigid material, has high rigidity and high precision, and is suitable for important tasks that require strong support and stability. This rigid structure ensures that the manipulator can maintain a stable state when performing tasks with high loads or requiring precise positioning. The purely rigid manipulator 4 can withstand large forces and avoid deformation under high stress conditions, ensuring the reliability of the task.

[0056] The flexible joint 5 is connected between the purely rigid manipulator 4 and the variable stiffness manipulator 6. The manipulator part is allowed to have a certain degree of flexibility in operation. By rope drive, the flexible joint 5 can adjust its posture to adapt to different operation requirements.

[0057] The variable stiffness manipulator 6 is located below the flexible joint 5 and connected to the variable stiffness gripper 7. The variable stiffness manipulator 6 can dynamically adjust its stiffness according to the task requirements. This design enables the manipulator to exhibit different characteristics in different scenarios: in some tasks, it can maintain a lower stiffness for flexible operation; in other tasks, it can increase stiffness to increase stability and load capacity. This variable stiffness capability enables the manipulator to have higher adaptability when facing complex tasks.

[0058] The variable stiffness gripper 7 is located at the bottom of the system and is connected to the variable stiffness robotic arm 6. The variable stiffness gripper 7 is the end effector of the system and is responsible for directly contacting and operating the object. The gripper can change its stiffness through an internal adjustment mechanism (such as vacuuming or inflating, etc.). When the gripper contacts the object, it can increase the stiffness to firmly grasp the object and prevent the object from slipping; when there is no contact with the object or flexible adjustment is required, the stiffness can be reduced to increase the flexibility of operation. This design greatly enhances the operating ability and adaptability of the gripper, and is suitable for a variety of different grasping and operating tasks.

[0059] The aluminum profile frame supports the structural part of the entire system. The aluminum profile frame is the skeleton of the entire system, responsible for supporting and protecting the various components of the system. The aluminum profile is light but strong, which can provide good structural stability while improving the portability and flexibility of the system. The modular design of the frame 1 makes the system easy to assemble, debug and maintain, and can be expanded and adjusted according to different test requirements.

[0060] Figure 2 Schematic diagram of a two-degree-of-freedom passive motion part 2 according to an embodiment of the present invention. Figure 3 1 is an exploded view of the two-degree-of-freedom passive motion part 2 of an embodiment of the present invention.

[0061] This design part allows the operator to adjust the connected mechanical arm or device on two axes through a clever mechanical structure. The connecting plate 8 can be connected to the aluminum profile bracket by screws. The retaining main board 9 and the retaining bracket 10 are used to firmly support the rest of the entire system. They are connected by a mortise and tenon structure and a vertical plate connector 14, and ensure that the structure will not loosen or deflect during adjustment. The aluminum tube 12 is then connected and reinforced by an adapter 13 to make the structure more stable. It allows rotation adjustment around a certain axis, providing the first passive degree of freedom. The design of the aluminum tube is not only light and has high strength, but also can maintain minimal deformation when subjected to external force, while allowing adjustment along the connection direction. In addition, the fixing bracket 11 can be fixed between the aluminum profile bracket and the retaining main board 9 to fix the first passive degree of freedom. When it is removed, the first degree of freedom can be liberated.

[0062] The adapter 15 allows rotational adjustment in a direction perpendicular to the first passive degree of freedom, and provides a second passive degree of freedom through the bearing 17, the shaft 18 and the connection between the adapter 15 and the connecting base plate 19. A spacer 36 is provided along the axial direction.

[0063] Figure 4 It is a schematic diagram of the active axis of the three-degree-of-freedom active motion part 3, the pure rigid robot arm 4 and the flexible joint 5 of an embodiment of the present invention. Figure 5 It is an exploded view of the active axis of the three-degree-of-freedom active motion part 3, the pure rigid robot arm 4 and the flexible joint 5 of an embodiment of the present invention. Figure 6 It is a partial schematic diagram of the flexible joint 5 according to an embodiment of the present invention. Figure 7 FIG. 4 is a diagram showing the wiring arrangement of the flexible joint 5 according to an embodiment of the present invention.

[0064] like Figures 4 to 5 As shown, the Yaw axis motor 20 (GM6020 motor) is responsible for driving the rotational motion of the entire system in the Yaw axis direction. It is connected to a base plate 23 through a motor fixing frame 21 and an aluminum column 22, and outputs a strong rotational torque to the inner ring of the cross roller bearing 37, ensuring that the system can rotate accurately and stably in the Yaw axis direction.

[0065] The other two motors (M2006 motors) 25 are installed on another base plate 24 through a motor fixing seat 26, and the motor winding disk 27 is connected to drive the wire rope 28 to transmit power to the bottom through the middle pulley. The purely rigid robotic arm 4 and the connecting print 30 are connected through a copper column 35, and are connected to the lower connecting print 30 through a universal joint 31. A threaded shaft 32 is embedded in the middle of the universal joint 31 for fixing, and a spring 38 is provided in the middle for passing the wire rope 28, and finally the wire rope 28 is pre-tightened through the pre-tightening print 33. The universal joint 31 allows the connected joints to rotate freely in different directions, providing higher flexibility. With the spring 38 passing between them, this design enables the flexible joint 5 to adapt to complex movement requirements while maintaining good structural stability.

[0066] By rotating the motor to pull or release the wire rope 28, multiple wire ropes 28 (such as Figure 6 to Figure 7 The wires 1, 2, 3 and 4 in the joint work together, and one motor drives two steel wires 28 at the same time, so that the joint can move flexibly in different directions. The pulley fixing frame 29 at one place is raised by the raising plate 34, so that the wires 2 and 4 are staggered to avoid interference.

[0067] At the same time, this design also ensures the stability and durability of the system during operation.

[0068] Figure 8 FIG. 1 is a layout diagram of a variable stiffness system according to an embodiment of the present invention. Figure 8 As shown, the variable stiffness manipulator 6 is the core component of the system and has adjustable mechanical stiffness. The manipulator changes its stiffness through internal air extraction and other operations, thereby providing optimal operational stability and flexibility under different operating conditions. This design enables the manipulator to dynamically adjust when performing tasks to adapt to different loads or operating environments.

[0069] The variable stiffness gripper 7 at the end of the variable stiffness manipulator 6 can adjust its stiffness according to the shape and characteristics of the contacted object. The design of the variable stiffness gripper 7 allows switching between flexible operation and rigid grasping, for example, it remains soft when grasping fragile or irregularly shaped objects, and becomes firm when a stable grip is required. The variable stiffness gripper 7 achieves efficient completion of complex tasks by working in coordination with the variable stiffness manipulator 6. At the same time, the stiffness of the gripper is adjusted by pumping air to harden it.

[0070] The copper column 35 provides a solid support and connection for the variable stiffness manipulator 6 and the variable stiffness gripper 7. The high-strength material and structural design ensure the stability of the entire system during operation, while also allowing the variable stiffness manipulator 6 and the variable stiffness gripper 7 to move flexibly. The variable stiffness manipulator 6 and the variable stiffness gripper 7 can be connected via a transfer printed part 40.

[0071] The rope drive test system of the present invention has the following characteristics in terms of technical innovation mechanism and advantages:

[0072] 1.Multi-degree-of-freedom adjustment mechanism:

[0073] The present invention designs a multi-degree-of-freedom adjustment mechanism including active and passive adjustment parts, which provides flexibility and adaptability of the manipulator and gripper in space. This mechanism ensures the precise control capability of the system in complex operating environments, can realize complex spatial motion, and meet various testing requirements.

[0074] 2. Rope drive and flexible joint control:

[0075] The system uses rope drive technology combined with flexible joint control to achieve precise operation and dynamic adjustment of the robot arm and gripper. This design improves the stability and accuracy of the system when performing various operation tasks, and enhances the system's adaptability and operational continuity.

[0076] 3. Dynamic stiffness adjustment:

[0077] The present invention supports the operation of the manipulator and gripper under different stiffness conditions, and can dynamically adjust the stiffness according to the task requirements. This capability enables the system to adapt to a variety of complex operating scenarios and different load conditions, enhancing the practicality and flexibility of the system.

[0078] 4. Modular design:

[0079] The system adopts modular design, which is convenient for disassembly, replacement and maintenance of components. This design simplifies the use of the system, prolongs its service life, reduces maintenance costs, and improves the economy and maintainability of the system.

[0080] 5. Manual adjustment function:

[0081] The system is designed with a manual adjustment mechanism on the top, allowing the operator to quickly adjust the system's posture and position during testing or operation. This feature improves the flexibility of system operation and enables the operator to make adjustments instantly, especially in scenarios that require manual operation or fine adjustment.

[0082] In summary, the present invention provides a rope-driven testing system with comprehensive functions, flexible operation and convenient maintenance, which can effectively test and verify the performance of variable-stiffness manipulator arms and grippers, and provides important technical support for practical applications.

[0083] The above content is a further detailed description of the present invention in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, without departing from the concept of the present invention, it can also make several substitutions or modifications to these described embodiments, and these substitutions or modifications should be regarded as belonging to the protection scope of the present invention. In the description of this specification, the description of the reference terms "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In the absence of mutual contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. A rope-driven test system for a variable stiffness manipulator and a variable stiffness gripper, characterized in that: include: Two-DOF passive motion part, used to manually adjust the posture of the robot arm and gripper; The three-degree-of-freedom active motion part cooperates with the two-degree-of-freedom passive motion part to achieve precise operation of the robotic arm through motor drive; A purely rigid robotic arm, located below the three-degree-of-freedom active motion part and connected to the flexible joint, is used to provide high rigidity and high precision of the operation; A flexible joint connects the purely rigid robotic arm and the variable stiffness robotic arm, allowing the robotic arm part to have a certain degree of flexibility during operation; A variable stiffness manipulator, located below the flexible joint and connected to a variable stiffness gripper, capable of dynamically adjusting its stiffness according to task requirements; The variable stiffness gripper is located at the bottom of the system and is connected to the variable stiffness robotic arm for direct contact and manipulation of objects. The frame supports the structure of the entire system and is used to install the two-degree-of-freedom passive motion part, the three-degree-of-freedom active motion part, the pure rigid manipulator, the flexible joint, the variable stiffness manipulator and the variable stiffness gripper.

2. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to claim 1, characterized in that: The two-degree-of-freedom passive motion part includes: a connecting plate, which is connected to the frame by screws; a retaining main board and a retaining bracket, which are used for stable support and are connected to each other by a mortise and tenon structure and a vertical plate connector; a reinforced aluminum tube, which is connected to the retaining main board by an adapter, provides a first passive degree of freedom, and allows rotation adjustment around a certain axis; a fixed bracket, which is fixed between the frame and the retaining main board, is used to fix the first passive degree of freedom, and can release this degree of freedom when removed; an adapter, which allows rotation adjustment in a direction perpendicular to the first passive degree of freedom, is connected to the connecting base plate by a bearing and a rotating shaft, and provides a second passive degree of freedom.

3. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to claim 1 or 2, characterized in that: The three-degree-of-freedom active motion part includes: a Yaw-axis motor drive, which is connected to the base plate with an aluminum column through a motor fixing frame, and outputs a rotational torque to the inner ring of a cross roller bearing to achieve precise and stable rotation of the system in the Yaw-axis direction; the rotation is converted into the degree of freedom of a linear pull rope, which is driven by another two motors, which are installed on the base plate through a motor fixing seat, connected to a motor winding drum to drive a wire rope, and transmit power to the robotic arm through an intermediate pulley to achieve precise operation of the robotic arm.

4. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to claim 3, characterized in that: The flexible joint is controlled by pulling or releasing the wire rope through the rotation of the motor.

5. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to claim 4, characterized in that: The flexible joint includes four steel cables, and one motor drives two steel cables simultaneously, so that the joint can move flexibly in different directions.

6. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to any one of claims 3 to 5, characterized in that: Also includes: Copper columns are used to connect the purely rigid robotic arm and the printed parts to provide structural stability; The universal joint is used to connect with the connecting printed part below. A threaded shaft is embedded in the middle for fixation. There is a spring in the middle for passing the wire rope. The wire rope is pre-tightened through the pre-tightening printed part, allowing the connected joint to rotate freely in different directions.

7. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to any one of claims 3 to 6, characterized in that: It also includes a raising plate, which is used to raise the fixing frame of the pulley so that the steel wire ropes can be staggered to avoid mutual interference.

8. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to any one of claims 1 to 7, characterized in that: The variable stiffness mechanical arm is a mechanism capable of adjusting mechanical stiffness so as to dynamically adjust its own stiffness according to task requirements.

9. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to any one of claims 1 to 8, characterized in that: The variable stiffness gripper serves as an end effector and changes its stiffness through an internal adjustment mechanism such as vacuuming or inflation, so as to increase the stiffness to firmly grasp the object when it contacts the object, and reduce the stiffness when it does not contact the object or needs flexible adjustment.

10. The rope-driven testing system for a variable stiffness manipulator and a variable stiffness gripper according to any one of claims 1 to 9, characterized in that: The frame is the aluminum profile frame.

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