High-Speed Variable Stiffness Torque Control Method and System for Improving the Precision of Collaborative Robots

Abstract

The present invention discloses a high-speed variable stiffness torque control method and system for improving the accuracy of a collaborative robot, belonging to the technical field of robot control. The method includes: detecting the magnitude of the force of the system through a torque sensor mounted on the robotic arm and feeding it back to the controller; the controller determines the working state of the system based on the monitored force and determines whether dynamic stiffness adjustment is required; when the system is in an environmental disturbance, impact or dragging state, a stiffness adjustment method that maintains torque continuity is used for dynamic stiffness adjustment. After obtaining a new stiffness value, it enters the normal state; when the system is in the normal working state, the stiffness value is obtained through normal calculation according to the variable stiffness dynamic curve determined by defining the adaptive stiffness function and the parameterization method, thereby controlling the rotation of the motor to achieve real-time high-speed variable stiffness accuracy control based on force control. Through the processing solution disclosed in the present invention, ultra-high-speed adjustment of the system stiffness can be achieved, enabling the surgical robot to meet the requirements of both safety and high precision at the same time.

Description

Technical Field

[0001] The present disclosure relates to the technical field of robot control, and particularly to a high-speed variable stiffness torque control method and system for improving the precision of collaborative robots. Background Art

[0002] With the continuous development of the economy and medical level, surgical robots are widely used in clinical surgeries. As a medical application, safety is of primary importance. Currently, due to safety considerations, surgical robots generally use collaborative robotic arms with low loads. The output force of the joints of such robotic arms is limited, and in case of a collision, it is relatively safe for medical staff. However, at the same time, surgical robots have high-precision requirements, usually higher than those of conventional collaborative robotic arms. High control precision requires high stiffness and the robotic arm to output greater force. Therefore, during surgery, safety and high precision are contradictory and difficult to balance. The present invention proposes a high-speed variable stiffness controller that can achieve ultra-high-speed adjustment of the system stiffness, enabling surgical robots to meet both safety and high-precision requirements. Summary of the Invention

[0003] In view of this, embodiments of the present disclosure provide a high-speed variable stiffness torque control method and system for improving the precision of collaborative robots to at least partially solve the problems existing in the prior art.

[0004] In a first aspect, embodiments of the present disclosure provide a high-speed variable stiffness torque control method for improving the precision of collaborative robots, including:

[0005] Detecting the magnitude of the force of the system through a torque sensor mounted on the robotic arm and feeding it back to the controller;

[0006] The controller determines the working state of the system based on the monitored force and determines whether dynamic stiffness adjustment is required;

[0007] When the system is in an environmental disturbance, collision, or dragging state, a rigid adjustment method that maintains torque continuity is used for dynamic stiffness adjustment. After obtaining a new stiffness value, it enters the normal state;

[0008] When the system is in a normal working state, the stiffness value is obtained through normal calculation according to the variable stiffness dynamic curve determined by defining the adaptive stiffness function and parameterization method, thereby controlling the rotation of the motor to achieve real-time high-speed variable stiffness precision control based on force control.

[0009] According to a specific implementation manner of embodiments of the present disclosure, the method further includes:

[0010] Constructing a motion control formula for the controller:

[0011] u = Ke = K(q - q d )

[0012] Among them, u is the control quantity, K is the proportional term representing rigidity, e is the error, q is the actual joint angle, and q d is the target joint angle.

[0013] Generally speaking, the control quantity (such as the torque of the motor) u changes with q - q d When e is very small, u is also very small, which will result in low system accuracy. For systems with high-precision requirements, in order to improve system accuracy, it is necessary to increase the value of K. However, due to safety requirements, u cannot be made too large, and the method of restricting u is to decrease the value of K. For surgical robots, high precision requires a high K value, while safety requires a low K value (with a low u), so it is difficult for the robot to achieve such control requirements.

[0014] To solve the above problems, the present invention proposes a precision control method for real-time variable rigidity based on force control technology, which is used to adjust the system stiffness K so that it can simultaneously meet the requirements of safety and high precision during surgery. The basic principle is as follows:

[0015] 1) Dynamic force control adjustment:

[0016] ① In the case of environmental disturbances, by increasing the value of K, e becomes smaller to improve system accuracy;

[0017] ② In the case of impact or dragging, by decreasing the value of K, e becomes larger to improve system safety; 2) High-speed variable rigidity adjustment based on force control technology:

[0018] In the present invention, the dynamic adjustment of the K value is not achieved by directly modifying the control parameters of the motor, but is directly implemented by using force control technology in system control. Among them, u = K(q, q d ), and the controller is only a function of position. The K value is implicitly represented during the process of calculating force, and the K value can be modified in each control cycle.

[0019] According to a specific implementation manner of an embodiment of the present disclosure, the controller determines the system working state according to the monitored force and determines whether dynamic rigidity adjustment is required, including:

[0020] When the system is in the case of environmental disturbances, increase the rigidity of the system to improve system accuracy.

[0021] According to a specific implementation manner of an embodiment of the present disclosure, the controller determines the system working state according to the monitored force and determines whether dynamic rigidity adjustment is required, and further includes:

[0022] When the system is in the case of impact or dragging, decrease the rigidity of the system to make the system flexible to improve system safety.

[0023] According to a specific implementation manner of an embodiment of the present disclosure, the method further includes:

[0024] When performing real-time variable stiffness control, first define an adaptive stiffness function and a parameterization method, and determine a stiffness curve, so that the system can calculate the stiffness according to the defined stiffness curve, and actively adjust the stiffness of the joint by adjusting the system stiffness.

[0025] According to a specific implementation manner of an embodiment of the present disclosure, the method further includes:

[0026] Set a variable stiffness curve u = f(e), and at the same time satisfy u < u max , u max is the upper limit maximum value;

[0027] Set two force control curves f1 and f2. Both the force control curves f1 and f2 have the following characteristics: at the proximal end of the curve, the e value is small and the K value is large, showing that the curve is relatively steep. When e = 0, the control input is 0; at the distal end of the curve, the curve is flat, and the curve value increases with e, but does not exceed u max ;

[0028] The formula of a curve K m can be expressed as:

[0029]

[0030] Among them, u max represents the maximum value of the output, m represents the stiffness coefficient, q represents the actual joint angle, and q d represents the target joint angle.

[0031] Different m represents different curves, such as the force control curves f1 and f2. The K proposed by the present invention m is for reference only. Other curves also have similar situations: there is a supremum extreme value; the near quotient derivative is large and the far quotient derivative is close to 0; there exists a curve that can be parameterized.

[0032] According to a specific implementation manner of an embodiment of the present disclosure, when the system is in an environmental disturbance, impact or dragging state, a rigid adjustment method that maintains torque continuity is used for dynamic rigid adjustment. After obtaining a new stiffness value, it enters the normal state, including:

[0033] Since in the control, it is necessary to make the shaft torque continuous. When e changes, u can keep the output unchanged.

[0034] The new stiffness curve can be solved according to e and u. When using the K m curve, solve for m. The specific calculation method is as follows:

[0035] When the system environment is disturbed, the accuracy is improved by increasing the system rigidity. When e becomes smaller, u remains unchanged, and according to the K m curve, a new m is solved;

[0036] When the system is impacted or dragged, the system is made flexible by reducing the system stiffness. When e becomes larger, u remains unchanged, and according to the K m curve, a new m is solved.

[0037] According to a specific implementation manner of the embodiment of the present disclosure, the method further includes:

[0038] When the system is in a normal working state or enters a normal working state after system dynamic rigidity adjustment, normal control is performed, and u = f(q, q d ) is normally calculated according to the curve formula.

[0039] According to a specific implementation manner of the embodiment of the present disclosure, the method further includes:

[0040] According to the obtained K value for dynamic adjustment, without directly modifying the control parameters of the motor, the force parameters are directly modified in the system control, so as to control the rotation of the motor, and finally the accuracy control of real-time high-speed variable rigidity based on force control is realized.

[0041] In a second aspect, the embodiment of the present disclosure provides a high-speed variable stiffness torque control system for improving the accuracy of a collaborative robot, including:

[0042] A detection device for detecting the force magnitude of the system through a torque sensor mounted on the robotic arm and feeding it back to the controller;

[0043] A judgment device for the controller to judge the working state of the system according to the monitored force and judge whether dynamic rigidity adjustment is required;

[0044] A first control device for, when the system is in an environment disturbance, impact or drag state, performing dynamic rigidity adjustment by using a rigid adjustment method that maintains torque continuity, and entering a normal state after obtaining a new stiffness value;

[0045] A second control device for, when the system is in a normal working state, normally calculating a stiffness value according to a variable rigidity dynamic curve determined by defining an adaptive rigidity function and a parameterization method, so as to control the rotation of the motor and realize the accuracy control of real-time high-speed variable rigidity based on force control.

[0046] In a third aspect, the embodiment of the present disclosure further provides a non-transitory computer-readable storage medium, which stores computer instructions for causing the computer to execute the high-speed variable stiffness torque control method for improving the accuracy of a collaborative robot in the foregoing first aspect or any implementation manner of the first aspect.

[0047] In a fourth aspect, an embodiment of the present disclosure further provides a computer program product. The computer program product includes a computing program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions that, when executed by a computer, cause the computer to execute the high-speed variable stiffness torque control method for improving the accuracy of a collaborative robot in the foregoing first aspect or any implementation manner of the first aspect.

[0048] The high-speed variable stiffness torque control solution for improving the accuracy of a collaborative robot in the embodiment of the present disclosure includes: detecting the magnitude of the force of the system through a torque sensor mounted on the robotic arm and feeding it back to the controller; the controller determines the working state of the system based on the monitored force and determines whether dynamic stiffness adjustment is required; when the system is in an environmental disturbance, impact or dragging state, a rigid adjustment method that maintains torque continuity is used for dynamic stiffness adjustment, and after obtaining a new stiffness value, it enters the normal state; when the system is in a normal working state, the stiffness value is obtained through normal calculation according to the variable stiffness dynamic curve determined by defining the adaptive stiffness function and the parameterization method, so as to control the rotation of the motor and achieve real-time high-speed variable stiffness accuracy control based on force control. Through the processing solution of the present disclosure, ultra-high-speed adjustment of the system stiffness can be achieved, enabling the surgical robot to meet the requirements of both safety and high precision simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0050] Figure 1 Structural diagram of a high-speed variable stiffness torque control system for improving the accuracy of a collaborative robot provided by an embodiment of the present disclosure;

[0051] Figure 2 Schematic flow chart of a high-speed variable stiffness torque control method for improving the accuracy of a collaborative robot provided by an embodiment of the present disclosure;

[0052] Figure 3 Schematic flow chart of another high-speed variable stiffness torque control method for improving the accuracy of a collaborative robot provided by an embodiment of the present disclosure;

[0053] Figure 4 Schematic diagram of a control curve provided by an embodiment of the present disclosure;

[0054] Figure 5 Structural diagram of another high-speed variable stiffness torque control system for improving the accuracy of a collaborative robot provided by an embodiment of the present disclosure. Detailed implementation manners

[0055] The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0056] The following uses specific specific examples to illustrate the implementation manners of the present disclosure. Those skilled in the art can easily understand other advantages and effects of the present disclosure from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. The present disclosure can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present disclosure without creative efforts fall within the scope of protection of the present disclosure.

[0057] It should be noted that the following describes various aspects of the embodiments within the scope of the appended claims. It should be obvious that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is illustrative only. Based on the present disclosure, those skilled in the art should understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement the device and / or practice the method. In addition, this device and / or this method can be implemented using other structures and / or functions in addition to one or more of the aspects described herein.

[0058] It should also be noted that the drawings provided in the following embodiments only illustrate the basic concept of the present disclosure in a schematic manner. Only the components related to the present disclosure are shown in the drawings, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in its actual implementation can be an arbitrary change, and the component layout type may also be more complex.

[0059] In addition, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the described aspects can be practiced without these specific details.

[0060] The embodiments of the present disclosure provide a high-speed variable stiffness torque control system for improving the accuracy of a collaborative robot. The high-speed variable stiffness torque control system for improving the accuracy of a collaborative robot provided in this embodiment can be executed by a computing device, which can be implemented as software, or implemented as a combination of software and hardware. The computing device can be integrally provided in a server, a client, etc.

[0061] See Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5 , a high-speed variable stiffness torque control method for improving the accuracy of a collaborative robot disclosed by the present invention includes the following steps:

[0062] Detect the force magnitude of the system through a torque sensor mounted on the robotic arm and feedback it to the controller;

[0063] The controller determines the working state of the system based on the monitored force and determines whether dynamic stiffness adjustment is required;

[0064] When the system is in an environmental disturbance, impact or dragging state, a rigid adjustment method that maintains torque continuity is used for dynamic stiffness adjustment, and after obtaining a new stiffness value, it enters the normal state;

[0065] When the system is in a normal working state, the stiffness value is obtained through normal calculation according to the variable stiffness dynamic curve determined by defining the adaptive stiffness function and the parameterization method, so as to control the rotation of the motor and achieve real-time high-speed variable stiffness precision control based on force control.

[0066] Specifically, torque sensors can be provided on each joint of the robot to measure the operating parameters of the robot joints during operation. At the same time, a robot real-time torque controller is also provided to perform force control on the robotic arm at a preset frequency (for example, a frequency of 1000 Hz per second).

[0067] According to a specific implementation manner of the present disclosure embodiment, the method further includes:

[0068] Construct a motion control formula for the controller:

[0069] u = Ke = K(q - q d )

[0070] where u is the control quantity, K is the proportional term representing stiffness, e is the error, q is the actual joint angle, and q d is the target joint angle.

[0071] According to a specific implementation manner of the present disclosure embodiment, the controller determines the working state of the system based on the monitored force and determines whether dynamic stiffness adjustment is required, including:

[0072] When the system is in an environmental disturbance situation, increase the stiffness of the system to improve the accuracy of the system.

[0073] According to a specific implementation manner of the present disclosure embodiment, the controller determines the working state of the system based on the monitored force and determines whether dynamic stiffness adjustment is required, and further includes:

[0074] When the system is impacted or dragged, reduce the rigidity of the system to make it flexible, so as to improve the safety of the system.

[0075] According to a specific implementation manner of an embodiment of the present disclosure, the method further includes:

[0076] When performing real-time variable rigidity control, first define an adaptive rigidity function and a parameterization method, determine the rigidity curve, so that the system calculates the stiffness according to the defined rigidity curve, and actively adjusts the stiffness of the joint by adjusting the system stiffness.

[0077] According to a specific implementation manner of an embodiment of the present disclosure, the method further includes:

[0078] Set the variable rigidity curve u = f(e), and at the same time satisfy u < u max , u max is the upper limit maximum value;

[0079] Set two force control curves f1 and f2. Both the force control curves f1 and f2 have the following characteristics: at the proximal end of the curve, the e value is small and the K value is large, showing that the curve is relatively steep. When e = 0, the control input is 0; at the distal end of the curve, the curve is flat, and the curve value increases with e, but does not exceed u max ;

[0080] The formula K of a curve m can be expressed as:

[0081]

[0082] where u max represents the maximum value of the output, m represents the rigidity coefficient, q represents the actual joint angle, and q d represents the target joint angle.

[0083] Different m represents different curves, such as the force control curves f1 and f2. The K proposed by the present invention m is for reference only. Other curves also have similar situations: there is a supremum extreme value; the near quotient derivative is large and the far quotient derivative is close to 0; there exists a curve that can be parameterized.

[0084] According to a specific implementation manner of an embodiment of the present disclosure, when the system is in an environmental disturbance, impacted or dragged state, a rigidity adjustment method that maintains torque continuity is adopted for dynamic rigidity adjustment. After obtaining a new stiffness value, it enters the normal state, including:

[0085] Since in the control, it is necessary to make the shaft torque continuous. When e changes, it is sufficient to keep the u output unchanged.

[0086] The new rigid curve can be solved according to e and u. When using the K m curve, m is solved. The specific calculation method is as follows:

[0087] When the system environment is disturbed, the accuracy is improved by increasing the system rigidity. When e becomes smaller, u remains unchanged. According to the K m curve, the new m is solved;

[0088] When the system is impacted or dragged, the system is made flexible by reducing the system stiffness. When e becomes larger, u remains unchanged. According to the K m curve, the new m is solved.

[0089] According to a specific implementation manner of the embodiment of the present disclosure, the method further includes:

[0090] When the system is in a normal working state or enters a normal working state after system dynamic rigidity adjustment, normal control is performed, and u = f(q, q d ) is normally calculated according to the curve formula.

[0091] According to a specific implementation manner of the embodiment of the present disclosure, the method further includes:

[0092] According to the obtained K value for dynamic adjustment, instead of directly modifying the control parameters of the motor, the force parameters are directly modified in the system control, so as to control the rotation of the motor, and finally realize the precision control of real-time high-speed variable rigidity based on force control.

[0093] Corresponding to the above method embodiment, see Figure 5 , the present invention also provides a high-speed variable stiffness torque control system 50 for improving the accuracy of a collaborative robot, including:

[0094] A detection device 501, configured to detect the force magnitude of the system through a torque sensor mounted on the robotic arm and feed it back to the controller;

[0095] A judgment device 502, configured to judge the working state of the system by the controller according to the monitored force and judge whether dynamic rigidity adjustment is required;

[0096] A first control device 503, configured to perform dynamic rigidity adjustment by using a rigid adjustment method that maintains torque continuity when the system is in an environmental disturbance, impact or drag state, and enter a normal state after obtaining a new stiffness value;

[0097] A second control device 504, configured to perform normal calculation to obtain a stiffness value according to a variable rigidity dynamic curve determined by defining an adaptive rigidity function and a parameterization method when the system is in a normal working state, so as to control the rotation of the motor and realize the precision control of real-time high-speed variable rigidity based on force control.

[0098] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, a segment of a program, or a portion of code that contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions noted in the blocks may occur in a different order than noted in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, or they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0099] The units involved in the embodiments described in the present disclosure can be implemented in software or in hardware. Among them, the name of the unit does not constitute a limitation on the unit itself in some cases. For example, the first acquisition unit can also be described as "the unit for acquiring at least two Internet protocol addresses".

[0100] It should be understood that the various parts of the present disclosure can be implemented by hardware, software, firmware, or a combination thereof.

[0101] As described above, the above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present disclosure should be covered by the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims

1. A high-speed variable stiffness torque control method for improving the accuracy of collaborative robots, characterized in that, Including: Detect the magnitude of the force of the system through the torque sensor mounted on the robotic arm and feed it back to the controller; The controller judges the working state of the system according to the monitored force and judges whether dynamic stiffness adjustment is needed; When the system is in an environmental disturbance, impact or dragging state, a rigid adjustment method that maintains torque continuity is used for dynamic stiffness adjustment. After obtaining a new stiffness value, it enters the normal state, including: when the system is environmentally disturbed, without changing the control quantity u of the controller, the accuracy is improved by increasing the system stiffness. When the system is impacted or dragged, without changing the control quantity u of the controller, the system is made flexible by reducing the system stiffness; When the system is in a normal working state, the stiffness value is obtained through normal calculation according to the variable stiffness dynamic curve determined by defining the adaptive stiffness function and the parameterization method, so as to control the rotation of the motor and realize the precision control of real-time high-speed variable stiffness based on force control.

2. The method according to claim 1, wherein The method further includes: For the controller, construct a motion control formula: u = Ke = K(q - q d ) where u is the control quantity, K is the proportional term representing rigidity, e is the error, q is the actual joint angle, and q d is the target joint angle.

3. The method according to claim 2, wherein The controller judges the working state of the system according to the monitored force and judges whether dynamic stiffness adjustment is needed, including: When the system is in an environmental disturbance situation, increase the stiffness of the system to improve the accuracy of the system.

4. The method according to claim 3, wherein The controller judges the working state of the system according to the monitored force and judges whether dynamic stiffness adjustment is needed, and further includes: When the system is impacted or dragged, reduce the stiffness of the system to make the system flexible to improve the safety of the system.

5. The method according to claim 4, wherein The method further includes: When performing real-time variable stiffness control, first define the adaptive stiffness function and the parameterization method to determine the stiffness curve, so that the system can calculate the stiffness according to the defined stiffness curve, and realize the active adjustment of the joint stiffness by adjusting the system stiffness.

6. The method according to claim 5, wherein The method further includes: Set the variable stiffness curve u = f(e), while satisfying u < u max , u max is the upper limit maximum value; Set two force control curves f1 and f2, and both the force control curves f1 and f2 have the following characteristics: at the proximal end of the curve, the e value is small and the K value is large, showing that the curve is relatively steep. When e = 0, the control input is 0; at the distal end of the curve, the curve is flat, and the curve value increases with the increase of e, but will not exceed u max ; Curve formula K m It is expressed as: , where u max represents the maximum value of the output, m represents the stiffness coefficient, q represents the actual joint angle, and q d represents the target joint angle.

7. The method according to claim 6, wherein When the system is in an environmental disturbance, impact or dragging state, a rigid adjustment method that maintains torque continuity is used for dynamic stiffness adjustment. After obtaining a new stiffness value, it enters the normal state, including: When the system environment is disturbed, the accuracy is improved by increasing the system rigidity. When e becomes smaller, u remains unchanged, and according to the K m curve, the new m is solved; When the system is impacted or dragged, the system becomes flexible by reducing the system stiffness. When e increases, u remains unchanged, and according to the K m curve, solve for the new m.

8. The method according to claim 7, wherein The method further includes: When the system is in a normal working state or enters a normal working state after system dynamic rigidity adjustment, normal control is carried out, and u = f(q, q d ) is calculated normally according to the curve formula.

9. The method according to claim 8, wherein The method further includes: According to the obtained K value for dynamic adjustment, instead of directly modifying the control parameters of the motor, directly modify the force parameters in the system control, so as to control the rotation of the motor, and finally realize the precision control of real-time high-speed variable stiffness based on force control.

10. A high-speed variable stiffness torque control system for improving the accuracy of collaborative robots, characterized in that, Including: A detection device for detecting the magnitude of the force of the system through the torque sensor mounted on the robotic arm and feeding it back to the controller; A judgment device for the controller to judge the working state of the system according to the monitored force and judge whether dynamic stiffness adjustment is needed; A first control device for, when the system is in an environmental disturbance, impact or dragging state, using a rigid adjustment method that maintains torque continuity for dynamic stiffness adjustment. After obtaining a new stiffness value, it enters the normal state, including: when the system is environmentally disturbed, without changing the control quantity u of the controller, the accuracy is improved by increasing the system stiffness. When the system is impacted or dragged, without changing the control quantity u of the controller, the system is made flexible by reducing the system stiffness; The second control device is used to perform normal calculations to obtain a stiffness value according to the variable stiffness dynamic curve determined by defining an adaptive stiffness function and a parameterization method when the system is in a normal working state, so as to control the rotation of the motor and achieve the precision control of real-time high-speed variable stiffness based on force control.

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