Robot, mechanical arm, mechanical arm detection control device and method thereof

Abstract

The invention discloses a robot, a mechanical arm and a mechanical arm detection control device and method, and belongs to the technical field of robots. The mechanical arm detection control method comprises the steps that S100, an actual torque signal of a motor unit is detected; s200, obtaining a detected actual torque signal of the motor unit, and processing and calibrating the actual torque signal to obtain an actual torque output by the motor unit; and S300, zero-force control is conducted on the mechanical arm according to the actual torque output by the motor unit and the mechanical arm compensation torque, and the mechanical arm compensation torque comprises the gravity torque of the mechanical arm, the joint friction torque of the mechanical arm and the inertia torque of the mechanical arm. The torque detection unit is directly integrated into the motor unit, installation and maintenance are simplified, the requirement for zero-force control of the mechanical arm is met, and controllability and safety of the robot are improved.

Description

Technical Field

[0001] The present invention application relates to the field of mechanical arms or robot technology, and more specifically, to a robot, a mechanical arm, a mechanical arm detection and control device and a method thereof. Background Art

[0002] The robotic arm is the most widely used automated mechanical device in the field of robotics, and is widely used in industrial manufacturing, medical treatment, entertainment services, military aerospace, semiconductor manufacturing, etc. In various application scenarios of the robotic arm, it is usually necessary to obtain the torque of the robotic arm in order to achieve high-precision control of the output torque of the robotic arm.

[0003] In the prior art, the common ways to obtain the torque of the mechanical arm include: the first way is to integrate a torque sensor at the end of the mechanical arm and use the torque sensor to detect the torque of the mechanical arm; the second way is to use the internal FOC (Field Oriented Control) current loop indirect detection method to indirectly calculate and obtain the torque of the mechanical arm. However, these methods usually have the following problems: 1) The cost of the torque sensor is high, which will greatly increase the hardware cost of the mechanical arm; the external integrated torque sensor is complex to install and maintain; the system integration of the entire mechanical arm is low, which increases the complexity and cost of the mechanical structure and control system of the mechanical arm; 2) The indirect detection method of the internal FOC current loop, which indirectly calculates the output torque by multiplying the phase current and the torque constant, has low accuracy and high delay, resulting in insufficient system response, and it is difficult to meet the application requirements of quickly adjusting the output torque and responding to external changes. The accuracy is low and the delay is high, which is difficult to meet the control requirements of high accuracy and low delay; 3) The zero-force control method of the mechanical arm is only suitable for robots with small-mass mechanical arms. Therefore, in order to partially or completely solve these technical problems, the present invention application provides a mechanical arm detection control device and method, a mechanical arm, and a robot. Summary of the invention

[0004] Based on this, the present invention application provides a robot, a robotic arm, a robotic arm detection control device and a method thereof, aiming to partially or completely solve the above technical problems. The present invention application is implemented through the following technical solutions:

[0005] In the first aspect, a robot arm detection control device includes: a motor unit, the motor unit is connected to a deceleration unit, and is used to drive the deceleration unit to decelerate; a braking unit, the braking unit is connected to the motor unit, and is used to brake the motor unit; a torque detection unit, the torque detection unit is connected to the motor unit, and is used to detect an actual torque signal of the motor unit; a deceleration unit, the deceleration unit is connected to a robot arm joint, and is used to drive the robot arm joint to move; a control unit, which obtains the actual torque signal of the motor unit detected by the torque detection unit, processes and calibrates the actual torque signal to obtain the actual torque output by the motor unit, and performs zero-force control on the robot arm according to the actual torque output by the motor unit and the robot arm compensation torque, and the robot arm compensation torque includes the gravity torque of the robot arm, the friction torque of the robot arm joint, and the inertia torque of the robot arm.

[0006] Optionally, the control unit includes: a gravity torque compensation module, a friction torque compensation module, an inertia torque compensation module, a compensation torque setting module and a compensation torque ratio calculation module, the gravity torque compensation module calculates the first compensation gravity torque Tg1 and the second compensation gravity torque Tg2 of the mechanical arm, the compensation torque setting module sets the additional compensation torque Ta, the friction torque compensation module calculates the compensation friction torque Tf of the mechanical arm, the inertia torque compensation module calculates the first compensation inertia torque Tm1 and the second compensation inertia torque Tm2 of the mechanical arm, and the compensation torque ratio calculation module includes a first compensation calculation unit and a second compensation calculation unit, the first compensation calculation unit calculates a first compensation torque ratio △T1, the first compensation torque ratio △T1 is a ratio of an actual torque Tp1 output by the motor unit to a sum Tq1 of the first compensation gravity torque Tg1, the additional compensation torque Ta and the first compensation inertia torque Tm1, the second compensation calculation unit calculates a second compensation torque ratio △T2, the second compensation torque ratio △T2 is a ratio of an actual torque Tp2 output by the motor unit to a sum Tq2 of the second compensation gravity torque Tg2, the compensation friction torque Tf and the second compensation inertia torque Tm2, ​​and satisfies:

[0007] When the speed w of the motor unit output shaft is less than or equal to wt, △T1=Tp1 / Tq1=Tp1 / (Tg1+Ta+Tm1)≦P1;

[0008] When the speed w of the motor unit output shaft is greater than wt, △T2=Tp2 / Tq2=Tp2 / (Tg2+Tf+Tm2)≦P2;

[0009] Among them, wt is the set speed. When the speed of the output shaft of the motor unit w≤wt, Tp1 is the actual torque output by the motor unit; Tq1 is the sum of the first compensating gravity torque Tg1, the additional compensating torque Ta and the first compensating inertia torque Tm1; Tg1 is the first compensating gravity torque of the robotic arm; Tm1 is the first compensating inertia torque of the robotic arm; P1 is the first preset value; when the speed of the output shaft of the motor unit w>wt, Tp2 is the actual torque output by the motor unit; Tq2 is the sum of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2; Tg2 is the second compensating gravity torque of the robotic arm, Tm2 is the second compensating inertia torque of the robotic arm, and Tf is the compensating friction torque of the robotic arm; P2 is the second preset value.

[0010] Optionally, the control unit also includes a compliance tracking coefficient calculation module and an additional compensation torque database, the additional compensation torque database including the first additional compensation torque Ta1, the second additional compensation torque Ta2, ..., the third additional compensation torque Ta3, ..., the nth additional compensation torque Tan, i = 1, 2, 3, ..., n, n is a positive integer; the compliance tracking coefficient calculation module calculates the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., the n-th compliance tracking coefficient Kn according to the first additional compensation torque Ta1, the second additional compensation torque Ta2, ..., the third additional compensation torque Ta3, ..., the n-th additional compensation torque Tan, satisfying: Ki = |(Tg1+Ta i+Tm1)-Tjmax| / Tjmax+|Tai-Tf| / Tf, wherein Tjmax is the maximum static friction torque, which is preset after being obtained through experiments or theoretical derivation.

[0011] Optionally, the control unit includes an additional compensation torque scheduling module, which sets the compensation torque module to obtain the minimum compliance tracking coefficient Kmin=min[K1, K2, ..., Kn] according to the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., the n-th compliance tracking coefficient Kn, and sets the additional compensation torque Ta according to the minimum compliance tracking coefficient Kmin; when the speed w of the output shaft of the motor unit>wt, the additional compensation torque scheduling module will set the additional compensation torque Ta set by the compensation torque module to 0.

[0012] Optionally, the robot arm detection control device M also includes: a temperature sensor, which collects temperature data of the motor unit when it is working; the torque detection unit includes a strain gauge module and a detection circuit module, the strain gauge module is installed on the output shaft of the motor unit, the strain gauge module collects strain data of the output shaft of the motor unit, and the strain gauge is connected to the detection circuit module; the control unit includes a strain-torque index module and a calibration module, the strain-torque index module establishes a strain-torque mapping table of the strain value measured by the strain gauge and the calculated torque value; the calibration module compensates and calibrates the strain value measured by the strain gauge to obtain the compensated strain value, and uses the strain-torque mapping table to obtain the actual torque output of the motor unit according to the compensated strain value.

[0013] In a second aspect, a robot arm detection control method includes the robot arm detection control device described in any one of the first aspects above, including the following steps:

[0014] Step S100: detecting the actual torque signal of the motor unit;

[0015] Step S200: acquiring the detected actual torque signal of the motor unit, processing and calibrating the actual torque signal to acquire the actual torque output by the motor unit;

[0016] Step S300: performing zero-force control on the robotic arm according to the actual torque output by the motor unit and the robotic arm compensation torque, wherein the robotic arm compensation torque includes the gravity torque of the robotic arm, the friction torque of the robotic arm joint, and the inertia torque of the robotic arm.

[0017] Optionally, in step S300, performing zero-force control on the robotic arm according to the actual torque output by the motor unit and the robotic arm compensation torque includes:

[0018] When the rotation speed w≤wt of the output shaft of the motor unit, the additional compensation torque Ta is set, and the first compensation torque ratio △T1 is calculated, △T1=Tp1 / Tq1=Tp1 / (Tg1+Ta+Tm1), and the first compensation torque ratio △T1 is less than or equal to the first preset value P1; or, when the rotation speed w>wt of the output shaft of the motor unit, the second compensation torque ratio △T2 is calculated, △T2=Tp2 / Tq2=Tp2 / (Tg2+Tf+Tm2), and the second compensation torque ratio △T2 is less than or equal to the second preset value P2;

[0019] Among them, wt is the set speed. When the speed of the output shaft of the motor unit w≤wt, Tp1 is the actual torque output by the motor unit; Tq1 is the sum of the first compensating gravity torque Tg1, the additional compensating torque Ta and the first compensating inertia torque Tm1; Tg1 is the first compensating gravity torque of the robotic arm; Tm1 is the first compensating inertia torque of the robotic arm; when the speed of the output shaft of the motor unit w>wt, Tp2 is the actual torque output by the motor unit; Tq2 is the sum of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2; Tg2 is the second compensating gravity torque of the robotic arm, Tm2 is the second compensating inertia torque of the robotic arm, and Tf is the compensating friction torque of the robotic arm.

[0020] Optionally, in step S300, setting the additional compensation torque Ta includes:

[0021] Calculate the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., the n-th compliance tracking coefficient Kn, satisfying:

[0022] Ki=|(Tg1+Ta i+Tm1)-Tjmax| / Tjmax+|Ta i-Tf| / Tf;

[0023] Wherein, Tjmax is the maximum static friction torque, which is preset after being obtained through experiments or theoretical derivation, Ta1 is the first additional compensation torque stored in advance, Ta2 is the second additional compensation torque stored in advance, ..., Ta i is the third additional compensation torque stored in advance, ..., Tan is the nth additional compensation torque stored in advance, i=1, 2, 3, ..., n, and n is a positive integer;

[0024] According to the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the ith compliance tracking coefficient Ki, ..., the nth compliance tracking coefficient Kn, the minimum compliance tracking coefficient Kmin = min[K1, K2, ..., Kn] is obtained, and the additional compensation torque Ta is obtained according to the minimum compliance tracking coefficient Kmin.

[0025] In a third aspect, a robotic arm comprises the robotic arm detection and control device described in any one of the first aspects or uses the robotic arm detection and control method described in any one of the second aspects.

[0026] A fourth aspect provides a robot, comprising the robotic arm described in the third aspect.

[0027] Beneficial technical effects of the present invention:

[0028] (1) In the present invention application, the torque detection unit is directly integrated into the motor unit, which simplifies the installation and maintenance of the torque detection unit. Ordinary strain gauges are used as components of the torque detection unit, which reduces the overall structural cost of the torque detection control device and the robotic arm, simplifies the hardware and software interfaces, and is suitable for robotic arms in various application scenarios and for zero-force control requirements, thereby improving the controllability and safety of the robotic arm or robot.

[0029] (2) In the present invention application, firstly, the compensation torque of the robot arm includes the gravity torque of the robot arm, the friction torque of the robot arm joint, the inertia torque of the robot arm and the set additional compensation torque. The torque detection unit detects the torque signal output by the motor unit in real time, and the control unit can obtain and process the calibrated actual torque. The control unit can also control the motor unit according to the robot arm compensation torque and the actual torque, so as to achieve zero-force control of the robot arm joint under the action of external force, thereby ensuring the controllability and stability of the robot arm movement. In addition, precise torque control reduces unnecessary energy consumption, improves energy utilization, and makes the movement of the robot arm more precise, meeting the actual high-demand operation requirements of the robot arm. The motor unit cooperates with the reduction unit to drive the robot arm, optimizes power transmission, and improves the movement efficiency of the robot arm. The braking unit can brake the motor unit to avoid dangers caused by abnormal conditions, enhance system safety, and protect equipment and personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of a mechanical arm detection control device applied by the present invention;

[0031] Figure 2 It is a schematic diagram of a robot arm detection control method applied by the present invention;

[0032] Figure 3 It is a schematic diagram of the working principle of the control unit applied for by the present invention;

[0033] Figure 4 It is a schematic diagram of the partial composition of the control unit of the present invention;

[0034] Description of the drawings: motor unit—10, brake unit—20, temperature sensor—30, first encoder—40, second encoder—50, torque detection unit—60, deceleration unit—70, control unit-80, robot arm detection control device—M. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure more clear, the embodiments of the present disclosure are further described in detail below in conjunction with the accompanying drawings and embodiments; it should be understood that the specific embodiments described herein are only used to explain the embodiments of the present disclosure and are not used to limit the embodiments of the present disclosure;

[0036] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any structural modification, change in proportion relationship or adjustment in size, without affecting the effects and purposes that can be produced by the present invention, should still fall within the scope of the technical contents disclosed by the present invention; at the same time, the terms such as "and" and "or" quoted in this specification are only for the convenience of description, and are not used to limit the scope of implementation. The change or adjustment of their relative relationship should also be regarded as the scope of implementation of the present invention without substantially changing the technical contents; in addition, the various embodiments of the present invention are not independent of each other, but can be combined;

[0037] The terms "first", "second" and "third" are used for descriptive purposes only and should not be understood as indicating or suggesting relative importance or implicitly indicating the number of the indicated technical features; thus, the features defined as "first", "second" and "third" may explicitly or implicitly include one or more of the features, and in the description of the present application, unless otherwise specified, "multiple" means two or more.

[0038] In the first aspect, a robot arm detection control device M includes: a motor unit 10, the motor unit 10 is connected to a deceleration unit 70, and is used to drive the deceleration unit 70 to decelerate; a braking unit 20, the braking unit 20 is connected to the motor unit 10, and is used to brake the motor unit 10; a torque detection unit 60, the torque detection unit 60 is connected to the motor unit 10, and is used to detect an actual torque signal of the motor unit 10; a deceleration unit 70, the deceleration unit 70 is connected to a robot arm joint, and is used to drive the robot arm joint to move; a control unit 80, which obtains the actual torque signal of the motor unit 10 detected by the torque detection unit 60, processes and calibrates the actual torque signal to obtain the actual torque output by the motor unit 10, and performs zero-force control on the robot arm according to the actual torque of the motor unit 10 and the robot arm compensation torque, and the robot arm compensation torque includes the gravity torque of the robot arm, the friction torque of the robot arm joint, and the inertia torque of the robot arm.

[0039] In existing robot teaching scenarios, zero-force control of the robotic arm can be understood as zero-force control of the robotic arm or the joints of the robotic arm. The target torque of the robotic arm can usually include the gravity torque of the robotic arm and the friction torque of the robotic arm joint. The actual torque output by the motor unit can usually be equal to the sum of the friction torque and the gravity torque. In this way, when an external force acts on the end of the robotic arm, the external force only needs to be used to overcome the inertia force and nonlinear coupling force of the robotic arm, and the robot will move in accordance with the external force. The friction and inertia forces in the robotic arm joints can be reduced or eliminated as much as possible to achieve zero-force control of the robotic arm joints in an environment not affected by friction and gravity, thereby improving the response speed, control accuracy and stability of the robotic arm.

[0040] However, the control method based on compensating gravity torque and friction torque is usually only applicable to robots with small mass manipulators. For serial joint robots with large mass manipulators, they usually have large inertia torques, and it is also necessary to compensate for the inertia torques and other torques of robots with large mass manipulators. Moreover, when the manipulator is in a stationary state and is dragged by an external force, the manipulator is affected by the static friction torque, and the external force dragging will be hindered by the static friction torque, which affects the zero-force control mode, and there will also be an impact between the gravity torque and the static friction torque. Therefore, the applicant discovered the above-mentioned multiple technical problems and proposed a technical solution for zero-force control of the manipulator that takes into account the gravity torque, friction torque and inertia torque of the manipulator at the same time and sets an additional compensation torque.

[0041] In the present application, firstly, the compensation torque of the robot arm includes the gravity torque of the robot arm, the friction torque of the robot arm joint, and the inertia torque of the robot arm, and an additional compensation torque is configured and set at the same time. The torque detection unit 60 detects the torque signal output by the motor unit in real time, and the control unit can accurately obtain and process the actual torque, and control the motor unit 10 according to the compensation torque of the robot arm and the actual torque, so as to achieve zero-force control of the robot arm joint under the action of external force, thereby ensuring the controllability and stability of the robot arm movement; in addition, precise torque control reduces unnecessary energy consumption, improves energy utilization, and makes the movement of the robot arm more precise, meeting the actual high-demand operation requirements of the robot arm. The motor unit 10 cooperates with the deceleration unit to drive the robot arm, optimizes power transmission, and improves the movement efficiency of the robot arm. The braking unit 20 can brake the motor unit 10 to avoid dangers caused by abnormal conditions and enhance the safety of the robot arm, the robot arm and the operator.

[0042] Optionally, the control unit includes a gravity torque compensation module 801, a friction torque compensation module 802, an inertia torque compensation module 803, a compensation torque setting module 804 and a compensation torque ratio calculation module 805, wherein the gravity torque compensation module 801 calculates the first compensation gravity torque Tg1 and the second compensation gravity torque Tg2 of the mechanical arm, the compensation torque setting module sets the additional compensation torque Ta, the friction torque compensation module calculates the compensation friction torque Tf of the mechanical arm, the inertia torque compensation module calculates the first compensation inertia torque Tm1 and the second compensation inertia torque Tm2 of the mechanical arm, and the compensation torque ratio calculation module includes The first compensation calculation unit includes a first compensation calculation unit and a second compensation calculation unit. The first compensation calculation unit calculates a first compensation torque ratio △T1, which is a ratio of an actual torque Tp1 output by the motor unit to a sum Tq1 of the first compensation gravity torque Tg1, the additional compensation torque Ta and the first compensation inertia torque Tm1. The second compensation calculation unit calculates a second compensation torque ratio △T2, which is a ratio of an actual torque Tp2 output by the motor unit to a sum Tq2 of the second compensation gravity torque Tg2, the compensation friction torque Tf and the second compensation inertia torque Tm2, ​​and satisfies:

[0043] When the speed w of the motor unit output shaft is less than or equal to wt, △T1=Tp1 / Tq1=Tp1 / (Tg1+Ta+Tm1)≦P1;

[0044] When the speed w of the motor unit output shaft is greater than wt, △T2=Tp2 / Tq2=Tp2 / (Tg2+Tf+Tm2)≦P2;

[0045] Among them, wt is the set speed. When the speed of the output shaft of the motor unit w≤wt, Tp1 is the actual torque output by the motor unit; Tq1 is the sum of the first compensating gravity torque Tg1, the additional compensating torque Ta and the first compensating inertia torque Tm1; Tg1 is the first compensating gravity torque of the robotic arm; Tm1 is the first compensating inertia torque of the robotic arm; P1 is the first preset value; when the speed of the output shaft of the motor unit w>wt, Tp2 is the actual torque output by the motor unit; Tq2 is the sum of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2; Tg2 is the second compensating gravity torque of the robotic arm, Tm2 is the second compensating inertia torque of the robotic arm, and Tf is the compensating friction torque of the robotic arm; P2 is the second preset value.

[0046] In some embodiments, wt is a set speed. For example, wt can be equal to 0 or not equal to 0. The range of wt is 0-2rad / s, i.e., 0rad / s, 1rad / s, 2rad / s or any numerical range between two. The range of the first preset value P1 can satisfy: 0.8≤P1≤1.3. The first preset value P1 can be equal to 1.0, 1.1, 1.2, etc. The range of the second preset value P2 can satisfy: 0.8≤P1≤1.3. The second preset value P2 can be equal to 1.0, 1.1, 1.2, etc. Of course, those skilled in the art can reasonably set the size of the first preset value P1 and the second preset value P2 according to actual conditions. The first preset value P1 and the second preset value P2 can also be other values ​​or other numerical ranges. In the zero-force control mode of the manipulator, the specific mathematical calculations of the gravity torque of the manipulator, the friction torque of the manipulator joint, and the inertia torque of the manipulator belong to the technical knowledge that can be obtained by ordinary technology, and the present invention application will not be repeated here.

[0047] In some embodiments, when the rotation speed w>wt of the output shaft of the motor unit, the friction torque is a dynamic friction torque, and the sum Tq2 of the second compensating gravity torque Tg2, the compensating friction torque Tf (corresponding to the dynamic friction torque of the robot joint or the robot arm) and the second compensating inertia torque Tm2 can be easily calculated, and the size of the second compensating torque ratio △T2 can be set under the limit of the second preset value P2, so as to determine the size of the actual torque Tp2 output by the motor unit to control the motor unit 10. For example, the sum Tq2 of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second inertia torque Tm2 can be proportional to or close to or equal to the actual torque Tp2 output by the motor unit, so as to realize the zero-force control mode of the robot arm under the action of external force. The zero-force control mode allows the external force to only overcome the nonlinear coupling force, so that the robot arm can better adapt to external forces and motion changes, improve the dynamic response capability and tracking performance of the motor unit, and expand the performance and application range of the robot arm, so that the robot arm can move faster.

[0048] In some embodiments, of course, when the output shaft of the motor unit runs at a speed w, the ratio between the actual torque Tp2 output by the current motor unit and the sum Tq2 of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second moment of inertia Tm2 can also be calculated to obtain the second compensating torque ratio △T2, and the motor unit 10 can be controlled according to the second compensating torque ratio △T2, the second preset value P2 and the current speed w of the motor unit. For example, the speed w of the current motor unit can be changed, and the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2 can be calculated, so that the sum Tq2 of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second moment of inertia Tm2 is proportional to or close to or equal to the actual torque Tp2 output by the motor unit, thereby realizing the zero-force control mode of the robotic arm under the action of external force.

[0049] In some embodiments, when the speed w≤wt of the output shaft of the motor unit (which can be considered as a low-speed stage), the friction torque can be considered as a static friction torque, and the drag torque will be hindered by the static friction torque, so that the zero-force control mode of the robot arm is affected. Accordingly, an additional compensation torque Ta can be set to consider the influence of the static friction torque on the external force drag. The sum Tq1 of the first compensation gravity torque Tg1, the additional compensation torque Ta and the first compensation inertia torque Tm1 can be calculated, and the first compensation torque ratio △T1 can be set under the limit of the first preset value P1, so as to determine the output torque of the motor. The size of the actual torque Tp1 output by the machine unit is used to control the motor unit 10. For example, the sum Tq1 of the first compensating gravity torque Tg1, the additional compensating torque Ta and the first compensating inertia torque Tm1 can be made proportional to or close to or equal to the actual torque Tp1 output by the motor unit, thereby realizing the starting of the motor and the zero-force control mode of the robot arm under the action of external force. Similarly, the zero-force control mode of the robot arm can enable the external force to overcome the nonlinear coupling force, etc., so that the robot arm can adapt to external forces and motion changes, thereby improving the dynamic response capability and tracking performance of the motor unit, and making the robot arm move faster.

[0050] However, in actual robot arm teaching scenarios, after considering the inertia torque, when the speed of the motor unit output shaft is w≤wt (which can be considered as a low-speed stage) and the friction torque is in the static friction torque stage, generally speaking, when the additional compensation torque Ta is smaller and much smaller than the static friction torque Tj, the actual torque Tp1 (i.e., Tg1+Ta+Tm1) output by the motor unit is also smaller, which may cause the actual torque Tp1 output by the motor unit to be smaller than the static friction torque Tj, and the dragging of the robot arm joints is affected, resulting in the mechanical The arm joint is difficult to follow the change of external force, and the zero-force control mode is affected and deteriorated; when the additional compensation torque Ta is larger and much larger than the static friction torque Tj, the actual torque Tp1 (i.e., Tg1+Ta+Tm1) calculated by the motor unit output is also larger, which will cause the actual torque Tp1 output by the motor unit to be too large, which will bring a certain impact to the robot arm, and the noise and vibration will also increase appropriately, resulting in energy waste, high startup energy consumption, and reduced control accuracy, affecting the accuracy of speed and position control, although when the external force acts on the joint of the robot arm, the zero-force control mode of the robot arm can be achieved. Therefore, the size of the adjustment torque can be reasonably set so that the actual torque Tp output by the motor unit meets both the motor unit startup performance and the zero-force control requirements.

[0051] Optionally, the control unit further includes a compliance tracking coefficient calculation module 806 and an additional compensation torque database, the additional compensation torque database including a first additional compensation torque Ta1, a second additional compensation torque Ta2, ..., a third additional compensation torque Ta3, ..., an nth additional compensation torque Tan, i=1, 2, 3, ..., n, where n is a positive integer; the compliance tracking coefficient calculation module calculates a first compliance tracking coefficient K1, a second compliance tracking coefficient K2, ..., an i-th compliance tracking coefficient Ki, ..., an n-th compliance tracking coefficient Kn according to the first additional compensation torque Ta1, the second additional compensation torque Ta2, ..., the third additional compensation torque Ta3, ..., and the n-th additional compensation torque Tan, satisfying:

[0052] Ki=|(Tg1+Ta i+Tm1)-Tjmax| / Tjmax+|Ta i-Tf| / Tf.

[0053] Among them, Tjmax is the maximum static friction torque, which is preset after being obtained according to experiments or theoretical derivation.

[0054] In some embodiments, the additional compensation torque database may store in advance the first additional compensation torque Ta1, the second additional compensation torque Ta2, ..., the third additional compensation torque Ta3, ..., the nth additional compensation torque Tan, i=1, 2, 3, ..., n, n is a positive integer, so as to realize that the additional compensation torque database includes the first additional compensation torque Ta1, the second additional compensation torque Ta2, ..., the third additional compensation torque Ta3, ..., the nth additional compensation torque Tan;

[0055] In the present invention, when the friction force is in the static friction stage, when the external force on the mechanical arm joint is less than the maximum static friction force, the mechanical arm joint does not slide relative to each other, but a small displacement occurs between the protrusions between the contact surfaces, and the actual torque output by the motor unit can be controlled to exert an external force on the contact surface. Generally speaking, the faster the external force is applied, the shorter the static friction force stays, and the smaller the maximum static friction force is. The slower the external force is applied, the longer the static friction force stays, and the greater the maximum static friction force is. Therefore, when the speed w≤wt of the output shaft of the motor unit, the present invention considers using different additional compensation torques to calculate the actual torque Tp1 required to be output by the motor unit, and according to the ratio of the actual torque Tp1 output by the motor unit and the static friction torque, the formula ((Tg1+Ta i+Tm1)-Tjmax) / Tjmax is set to improve the dragging performance of the motor unit at startup and reduce the dragging obstacle of the external force to the mechanical arm. At the moment of starting and reversing the joint of the robot arm, the relative speed between the contact surfaces will suddenly change, causing the friction torque to fluctuate when the static friction is converted to dynamic friction, affecting the zero-force control mode effect of the robot arm under the action of external force. Therefore, the present invention application considers the possible changes in the dynamic friction torque (which can correspond to the compensation friction torque Tf) and the static friction torque in the static friction stage when the speed of the output shaft of the motor unit w>wt and the friction force is in the dynamic friction stage, and then sets the formula (Ta i-Tf) / Tf to evaluate the degree of fluctuation of the friction torque during the static friction conversion, so as to improve the accuracy and stability of the zero-force control mode and reduce the fluctuation caused by the motor unit. On this basis, the present invention application fully considers the zero-force control of the robotic arm in the static friction stage and the dynamic friction stage, and uses the additional compensation torque to calculate the first compliance tracking coefficient K1, the second compliance tracking coefficient K2,..., the i-th compliance tracking coefficient Ki,..., the n-th compliance tracking coefficient Kn, and according to the first compliance tracking coefficient K1, the second compliance tracking coefficient K2,..., the i-th compliance tracking coefficient Ki,..., the n-th compliance tracking coefficient Kn, the zero-force control of the robotic arm can be optimized.

[0056] In some embodiments, the i-th compliance tracking coefficient Ki may be further optimized in detail. The optimized i-th compliance tracking coefficient Kei is:

[0057] Ke i=|(Tg1+Tai+Tm1)-Tjmax| / Tjmax+|Tai-Tf| / Tf-|Tjmax-Tf| /

[0058] (Tf+Tjmax)

[0059] In some embodiments, when considering evaluating the degree of fluctuation of the friction torque during the static friction conversion, the relative relationship between Tjmax and Tf can be further considered, and the relationship between |Tai-Tf| / Tf-|Tjmax-Tf| / (Tf+Tjmax) can be integrated to more carefully grasp the fluctuation details of the friction torque during the static friction conversion process, thereby effectively improving the control accuracy of the zero-force control mode in practical applications.

[0060] Optionally, the control unit includes an additional compensation torque scheduling module, which sets the compensation torque module to obtain the minimum compliance tracking coefficient Kmin=min[K1, K2, ..., Kn] according to the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., the n-th compliance tracking coefficient Kn, and sets the additional compensation torque Ta according to the minimum compliance tracking coefficient Kmin. When the speed w of the output shaft of the motor unit is greater than wt, the additional compensation torque scheduling module will schedule the additional compensation torque Ta set by the compensation torque module to 0.

[0061] In some embodiments, first, after the compliance tracking coefficient calculation module calculates the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., and the n-th compliance tracking coefficient Kn, the compensation torque setting module can obtain the minimum compliance tracking coefficient Kmin=min[K1, K2, ..., Kn]. The minimum compliance tracking coefficient Kmin usually means: a smaller degree of fluctuation of the friction torque in the static friction conversion process and / or a lower starting drag cost of the motor unit. The minimum compliance tracking coefficient Kmin corresponds to the additional compensation torque in the additional compensation torque database, that is, the additional compensation torque Ta that needs to be set by the compensation torque setting module; in addition, when the friction torque is converted from static friction to dynamic friction, that is, when the speed w>wt of the output shaft of the motor unit, the actual torque of the motor unit 10 can be controlled by the compensation friction torque Tf. At this time, the additional compensation torque scheduling module can schedule the additional compensation torque Ta set by the compensation torque setting module to 0.

[0062] Optionally, the robot arm detection control device M also includes: the robot arm detection control device M also includes: a temperature sensor 30, the temperature sensor collects temperature data of the motor unit when it is working; the torque detection unit 60 includes a strain gauge module and a detection circuit module, the strain gauge module is installed on the output shaft of the motor unit 10, the strain gauge module collects strain data of the output shaft of the motor unit 10, and the strain gauge is connected to the detection circuit module; the control unit includes a strain-torque index module 807 and a calibration module 808, the strain-torque index module establishes a strain-torque mapping table of the strain value measured by the strain gauge and the calculated torque value; the calibration module compensates and calibrates the strain value measured by the strain gauge to obtain the compensated strain value, and uses the strain-torque mapping table to obtain the actual torque output of the motor unit 10 according to the compensated strain value.

[0063] In the present application, the strain gauge module is arranged on the rotor output shaft of the motor unit 10. The strain gauge is a high-sensitivity metal foil strain gauge. The strain gauge can be firmly attached to the metal surface of the pre-treated rotor output shaft using high-strength epoxy resin glue. The strain gauge module includes 4 strain gauges, which are distributed in a ring array; the detection circuit module includes: a Wheatstone bridge circuit, an amplifier and an ADC analog-to-digital converter. The strain gauges are connected into a full-bridge structure. A high-gain, low-noise instrument amplifier can be used to amplify the weak strain analog signal, and a 24-bit or 16-bit high-precision ADC (such as ADS1220 or AD7190) is used to convert the strain analog signal into a digital electrical signal. In this way, the actual torque signal of the motor unit 10 detected by the torque detection unit 60 will be transmitted to the control unit as the above-mentioned digital electrical signal.

[0064] However, in actual processes, strain gauges are usually affected by factors such as temperature and creep. After the torque detection unit 60 detects the actual torque signal of the motor unit 10, the actual torque signal needs to be processed and calibrated to obtain the actual torque of the motor unit 10. The applicant has discovered the technical problem of how to perform torque calibration and proposed a corresponding technical solution.

[0065] In some embodiments, the strain-torque indexing module 807 establishes a strain-torque mapping table of the strain value measured by the strain gauge and the torque value calculated. Specifically, it includes:

[0066] In some embodiments, establishing a strain-torque mapping table of strain values ​​measured by strain gauges and calculated torque values ​​includes: dividing the strain value range into n intervals, recorded as strain interval 1, strain interval 2, ..., strain interval i..., strain interval n, i = 1, 2, 3..., n, n is a positive integer; dividing the torque strain value range into n intervals, recorded as torque interval 1, torque interval 2, ..., torque interval j..., torque interval n, j = 1, 2, 3..., n, n is a positive integer, and torque interval j can store information such as torque average value, torque value range, and torque linear fitting value; then, creating a two-dimensional strain-torque mapping index table L, where L[i][j] in the strain-torque mapping index table L represents the corresponding mapping relationship when the strain value measured by the strain gauge is in strain interval i and the actual torque value is in torque interval [j]. It should be noted that the strain data of the rotor output shaft of the motor unit 10 can be automatically collected multiple times under different temperatures and different loads, so as to obtain sufficient samples, and then the strain-torque mapping table can be established.

[0067] In some embodiments, the calibration module performs compensation calibration on the strain measured by the strain gauge to obtain a compensated strain value, and obtains the actual torque output by the motor unit 10 using a strain-torque mapping table according to the compensated strain value. Specifically, it includes:

[0068] In some embodiments, specifically, the strain value g measured by the strain gauge can be subjected to temperature and creep compensation by a strain compensation formula to obtain a compensated strain value f. The strain compensation formula includes:

[0069] f=g-E1△TC(1-e -t / P );

[0070] Where E1 is the thermal expansion coefficient of the strain gauge, △T is the temperature change, C is the creep coefficient, P is the time constant, and t is the working time of the strain gauge.

[0071] In some embodiments, the working time of the strain gauge can be the cumulative working time or the single working time, etc. When the strain gauge measures the actual strain value g of the output shaft of the motor unit 10, the temperature data measurement of the motor unit when working and the working time of the strain gauge are determined, the above-mentioned strain compensation formula can be used to calculate the compensated strain value f. When the two-dimensional strain-torque mapping index table L is used to index the corresponding torque value that will fall within the torque interval s, the torque information in the torque interval s can be searched accordingly to obtain the torque value, that is, the processing and calibration of the actual torque signal is completed to obtain the actual torque output by the motor unit 10.

[0072] In some embodiments, the robot arm detection control device M may further include a first encoder 40 and a second encoder 50. One of the first encoder 40 and the second encoder 50 collects the rotation speed of the motor unit, and the other collects the position of the motor unit (for example, the rotation angle). In this way, simultaneously collecting the rotation speed information and the position information of the motor unit can realize more comprehensive state monitoring of the motor unit. The rotation speed information helps to understand the running speed stability of the motor unit, and the position information can accurately control the movement trajectory of the motor unit. At the same time, the two can also cooperate with each other to more accurately feedback the working condition of the motor unit, thereby providing a basis for the precise control of the robot arm and reducing the control error of the robot arm.

[0073] Therefore, in the present invention application, the torque detection unit is directly integrated into the motor unit, which simplifies installation and maintenance. Ordinary strain gauges are used as the components of the torque detection unit, which reduces the overall structural cost of the torque detection control device and the robotic arm, simplifies the hardware and software interfaces, and is suitable for robotic arms in various application scenarios and for the requirements of zero-force control of robotic arms, thereby improving the controllability and safety of the robotic arm or robot.

[0074] In a second aspect, a robot arm detection control method includes the robot arm detection control device described in any one of the first aspects above, including the following steps:

[0075] Step S100: Detecting the actual torque signal of the motor unit 10;

[0076] Step S200: acquiring the detected actual torque signal of the motor unit 10, processing and calibrating the actual torque signal to acquire the actual torque output by the motor unit 10;

[0077] Step S300: performing zero-force control on the robotic arm according to the actual torque output by the motor unit 10 and the robotic arm compensation torque, wherein the robotic arm compensation torque includes the gravity torque of the robotic arm, the friction torque of the robotic arm joint, and the inertia torque of the robotic arm.

[0078] It should be noted that a robot arm detection and control method applied for in the present invention includes any one of the robot arm detection and control devices in the first aspect, and accordingly also includes: all the technical problems, technical solutions and technical effects recorded in any one of the robot arm detection and control devices in the first aspect, which will not be repeated in the present application.

[0079] In the present application, firstly, the compensation torque of the robot arm includes the gravity torque of the robot arm, the friction torque of the robot arm joint, and the inertia torque of the robot arm, and the additional compensation torque is configured and set at the same time. The torque signal output by the motor unit is detected in real time, and the actual torque of the motor unit 10 is obtained by processing and calibration. The motor unit 10 is controlled according to the robot arm compensation torque and the actual torque. Zero-force control of the robot arm joint under external force can be achieved, thereby ensuring the controllability and stability of the robot arm movement. Accurate torque control reduces unnecessary energy consumption, improves energy utilization, and makes the movement of the robot arm more precise, meeting the actual operation needs of the robot arm.

[0080] Optionally, in step S300, performing zero-force control on the motor unit 10 according to the actual torque output by the motor unit 10 and the compensation torque of the robot arm includes:

[0081] When the rotation speed w≤wt of the output shaft of the motor unit, the additional compensation torque Ta is set, and the first compensation torque ratio △T1 is calculated, △T1=Tp1 / Tq1=Tp1 / (Tg1+Ta+Tm1), and the first compensation torque ratio △T1 is less than or equal to the first preset value P1; or, when the rotation speed w>wt of the output shaft of the motor unit, the second compensation torque ratio △T2 is calculated, △T2=Tp2 / Tq2=Tp2 / (Tg2+Tf+Tm2), and the second compensation torque ratio △T2 is less than or equal to the second preset value P2;

[0082] Among them, wt is the set speed. When the speed of the output shaft of the motor unit w≤wt, Tp1 is the actual torque output by the motor unit; Tq1 is the sum of the first compensating gravity torque Tg1, the additional compensating torque Ta and the first compensating inertia torque Tm1; Tg1 is the first compensating gravity torque of the robotic arm; Tm1 is the first compensating inertia torque of the robotic arm; when the speed of the output shaft of the motor unit w>wt, Tp2 is the actual torque output by the motor unit; Tq2 is the sum of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2; Tg2 is the second compensating gravity torque of the robotic arm, Tm2 is the second compensating inertia torque of the robotic arm, and Tf is the compensating friction torque of the robotic arm.

[0083] In some embodiments, when the rotation speed w>wt of the output shaft of the motor unit, the friction torque is a dynamic friction torque, and the sum Tq2 of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2 can be easily calculated, and the size of the second compensating torque ratio △T2 can be set under the restriction of the second preset value P2, and then the size of the actual torque Tp2 output by the motor unit can be determined to control the motor unit 10. For example, the sum Tq2 of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second inertia torque Tm2 can be proportional to or close to or equal to the actual torque Tp2 output by the motor unit, and then the zero-force control mode of the robotic arm under the action of external force can be realized. The zero-force control mode allows the external force to only overcome the nonlinear coupling force, so that the robotic arm can better adapt to external forces and motion changes, improve the dynamic response capability and tracking performance of the motor unit, and expand the performance and application range of the robotic arm, so that the robotic arm moves faster.

[0084] Of course, when the output shaft of the motor unit runs at a speed w, the ratio between the actual torque Tp2 output by the current motor unit and the sum Tq2 of the second compensating gravity torque Tg2, the compensating friction torque Tf (which can correspond to the dynamic friction torque of the robotic arm joint or robotic arm) and the second moment of inertia Tm2 can also be calculated to obtain the second compensating torque ratio △T2, and the motor unit 10 can be controlled according to the second preset value P2, the second compensating torque ratio △T2 and the current speed w of the motor unit to change the size of the current speed w of the motor unit, and the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2 can be calculated so that the sum Tq2 of the compensating friction torque Tf and the second moment of inertia Tm2 is proportional to or close to or equal to the actual torque Tp2 output by the motor unit, thereby realizing the zero-force control mode of the robotic arm under the action of external force.

[0085] In some embodiments, when the speed w≤wt of the output shaft of the motor unit, the friction torque can be considered as the static friction torque, and the drag torque will be hindered by the static friction torque, so that the zero-force control mode of the robot arm is affected. Accordingly, an additional compensation torque Ta can be set to consider the influence of the static friction torque on the external force drag. The sum Tq1 of the first compensation gravity torque Tg1, the additional compensation torque Ta and the first compensation inertia torque Tm1 can be calculated, and the first compensation torque ratio △T1 can be set under the restriction of the first preset value P1, so as to determine the output torque of the motor unit. The size of the actual torque Tp1 output can be used to control the motor unit 10. For example, the sum Tq1 of the first compensating gravity torque Tg1, the additional compensating torque Ta and the first compensating inertia torque Tm1 can be made proportional to or close to or equal to the actual torque Tp1 output by the motor unit, thereby realizing the start-up of the motor and the zero-force control mode of the robot arm under the action of external force. The zero-force control mode of the robot arm can enable the external force to overcome the nonlinear coupling force, etc., and enable the robot arm to adapt to external forces and motion changes, thereby improving the dynamic response capability and tracking performance of the motor unit and making the robot arm move faster.

[0086] Optionally, setting the additional compensation torque Ta includes:

[0087] Calculate the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., the n-th compliance tracking coefficient Kn, satisfying:

[0088] Ki=|(Tg1+Ta i+Tm1)-Tjmax| / Tjmax+|Tai-Tf| / Tf;

[0089] Wherein, Tjmax is the maximum static friction torque, which is preset after being obtained through experiments or theoretical derivation, Ta1 is the first additional compensation torque stored in advance, Ta2 is the second additional compensation torque stored in advance, ..., Ta i is the third additional compensation torque stored in advance, ..., Tan is the nth additional compensation torque stored in advance, i=1, 2, 3, ..., n, and n is a positive integer;

[0090] According to the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the ith compliance tracking coefficient Ki, ..., the nth compliance tracking coefficient Kn, the minimum compliance tracking coefficient Kmin = min[K1, K2, ..., Kn] is obtained, and the additional compensation torque Ta is obtained according to the minimum compliance tracking coefficient Kmin.

[0091] In the present application, after the compliance tracking coefficient calculation module calculates the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., and the n-th compliance tracking coefficient Kn, the compensation torque setting module can obtain the minimum compliance tracking coefficient Kmin=min[K1, K2, ..., Kn]. The minimum compliance tracking coefficient Kmin usually means: a smaller degree of fluctuation of the friction torque in the static friction conversion process and / or a lower starting drag cost of the motor unit. The minimum compliance tracking coefficient Kmin corresponds to the additional compensation torque in the additional compensation torque database, that is, the additional compensation torque Ta that the compensation torque setting module needs to set.

[0092] In some embodiments, the i-th compliance tracking coefficient Ki may be further optimized in detail. The optimized i-th compliance tracking coefficient Kei is:

[0093] Ke i=|(Tg1+Tai+Tm1)-Tjmax| / Tjmax+|Tai-Tf| / Tf-|Tjmax-Tf| /

[0094] (Tf+Tjmax)

[0095] In some embodiments, when considering evaluating the degree of fluctuation of the friction torque during the static friction conversion, the relative relationship between Tjmax and Tf can be further considered, and the relationship between |Tai-Tf| / Tf-|Tjmax-Tf| / (Tf+Tjmax) can be integrated to more carefully grasp the fluctuation details of the friction torque during the static friction conversion process, thereby effectively improving the control accuracy of the zero-force control mode in practical applications.

[0096] Optionally, in step S300, performing zero-force control on the motor unit 10 according to the actual torque of the motor unit 10 and the compensation torque of the robot arm also includes: when the rotation speed w>wt of the output shaft of the motor unit, scheduling the additional compensation torque Ta set by the compensation torque module to 0.

[0097] In some embodiments, after the friction torque is converted from static friction to dynamic friction, the actual torque of the motor unit 10 can be controlled by the compensation friction torque Tf accordingly. At this time, the additional compensation torque Ta can be scheduled to be 0.

[0098] In a third aspect, a robotic arm comprises the robotic arm detection and control device described in any one of the first aspects or uses the robotic arm detection and control method described in any one of the second aspects.

[0099] Similarly, it should be noted that the robot arm detection control device including any one of the first aspects or the robot arm detection control method using any one of the second aspects correspondingly also includes: all the technical problems, technical solutions and technical effects recorded in any one of the robot arm detection control devices in the first aspect, or all the technical problems, technical solutions and technical effects recorded in any one of the robot arm detection control methods in the second aspect, and the present invention application will not be repeated here.

[0100] A fourth aspect provides a robot, comprising the robotic arm described in the third aspect.

[0101] In the robot applied for in the present invention, the robot's mechanical arm compensation torque includes the mechanical arm's gravity torque, the mechanical arm joint friction torque, the mechanical arm's inertia torque, and an additional compensation torque is configured and set at the same time. The torque detection unit detects the torque signal output by the motor unit in real time, and the control unit can accurately obtain and process the actual torque, and control the motor unit according to the mechanical arm compensation torque and the actual torque, so as to achieve zero-force control of the robot's mechanical arm joints under external forces, thereby ensuring the stability and accuracy of the robot's movement; precise torque control reduces unnecessary energy consumption, improves energy utilization, and makes the robot's movement more precise, meeting the actual operation needs of the robot, avoiding dangers caused by abnormal situations, enhancing the safety of robot operation, and protecting the mechanical arm and operator.

[0102] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] Those skilled in the art can understand that the steps, measures, and schemes in the various operations, methods, and processes discussed in the present application can be alternated, changed, combined, or deleted; further, other steps, measures, and schemes in the various operations, methods, and processes discussed in the present application can also be alternated, changed, rearranged, decomposed, combined, or deleted; further, the steps, measures, and schemes in the various operations, methods, and processes disclosed in the present application in the prior art can also be alternated, changed, rearranged, decomposed, combined, or deleted;

[0104] The above-described embodiments only express several implementation methods of the embodiments of the present disclosure, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the patent scope of the embodiments of the present disclosure. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the embodiments of the present disclosure, which all belong to the protection scope of the embodiments of the present disclosure. Therefore, the protection scope of the embodiments of the present disclosure shall be based on the attached claims.

Claims

1. A robot arm detection control device, characterized in that: include: The motor unit is connected to the reduction unit and is used to drive the reduction unit to reduce speed; A brake unit, the brake unit is connected to the motor unit and is used to brake the motor unit; A torque detection unit, the torque detection unit is connected to the motor unit and is used to detect an actual torque signal of the motor unit; A reduction unit, the reduction unit is connected to the joints of the robotic arm and is used to drive the joints of the robotic arm to move; The control unit obtains the actual torque signal of the motor unit detected by the torque detection unit, processes and calibrates the actual torque signal to obtain the actual torque output by the motor unit, and performs zero-force control on the robotic arm according to the actual torque output by the motor unit and the compensation torque of the robotic arm. The compensation torque of the robotic arm includes the gravity torque of the robotic arm, the friction torque of the robotic arm joint, and the inertia torque of the robotic arm.

2. A robot arm detection control device according to claim 1, characterized in that: The control unit includes: a gravity moment compensation module, a friction moment compensation module, an inertia moment compensation module, a compensation moment setting module and a compensation moment ratio calculation module. The gravity moment compensation module calculates the first compensation gravity moment Tg1 and the second compensation gravity moment Tg2 of the mechanical arm. The compensation moment setting module sets the additional compensation moment Ta. The friction moment compensation module calculates the compensation friction moment Tf of the mechanical arm. The inertia moment compensation module calculates the first compensation inertia moment Tm1 and the second compensation inertia moment Tm2 of the mechanical arm. The compensation moment ratio calculation module includes a first compensation calculation unit and a second compensation calculation unit. The second compensation calculation unit, the first compensation calculation unit calculates the first compensation torque ratio △T1, the first compensation torque ratio △T1 is the ratio of the actual torque Tp1 output by the motor unit to the sum Tq1 of the first compensation gravity torque Tg1, the additional compensation torque Ta and the first compensation inertia torque Tm1, the second compensation calculation unit calculates the second compensation torque ratio △T2, the second compensation torque ratio △T2 is the ratio of the actual torque Tp2 output by the motor unit to the sum Tq2 of the second compensation gravity torque Tg2, the compensation friction torque Tf and the second compensation inertia torque Tm2, ​​and satisfies: When the speed w of the motor unit output shaft is less than or equal to wt, △T1=Tp1 / Tq1=Tp1 / (Tg1+Ta+Tm1)≦P1; When the speed w of the motor unit output shaft is greater than wt, △T2=Tp2 / Tq2=Tp2 / (Tg2+Tf+Tm2)≦P2; Among them, wt is the set speed. When the speed of the output shaft of the motor unit w≤wt, Tp1 is the actual torque output by the motor unit; Tq1 is the sum of the first compensating gravity torque Tg1, the additional compensating torque Ta and the first compensating inertia torque Tm1; Tg1 is the first compensating gravity torque of the robotic arm; Tm1 is the first compensating inertia torque of the robotic arm; P1 is the first preset value; when the speed of the output shaft of the motor unit w>wt, Tp2 is the actual torque output by the motor unit; Tq2 is the sum of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2; Tg2 is the second compensating gravity torque of the robotic arm, Tm2 is the second compensating inertia torque of the robotic arm, and Tf is the compensating friction torque of the robotic arm; P2 is the second preset value.

3. A robot arm detection control device according to claim 2, characterized in that: The control unit also includes a compliance tracking coefficient calculation module and an additional compensation torque database, the additional compensation torque database includes a first additional compensation torque Ta1, a second additional compensation torque Ta2, ..., a third additional compensation torque Ta3, ..., and an nth additional compensation torque Tan, i=1, 2, 3, ..., n, where n is a positive integer; the compliance tracking coefficient calculation module calculates the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., and the n-th compliance tracking coefficient Kn according to the first additional compensation torque Ta1, the second additional compensation torque Ta2, ..., the third additional compensation torque Ta3, ..., and the n-th additional compensation torque Tan, satisfying: Ki=|(Tg1+Tai+Tm1)-Tjmax| / Tjmax+|Tai-Tf| / Tf, wherein Tjmax is the maximum static friction torque, which is preset after being obtained through experiments or theoretical derivation.

4. A robot arm detection control device according to claim 3, characterized in that: The control unit includes an additional compensation torque scheduling module, which sets the compensation torque module to obtain a minimum compliance tracking coefficient Kmin=min[K1, K2, ..., Kn] according to the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., the n-th compliance tracking coefficient Kn, and sets the additional compensation torque Ta according to the minimum compliance tracking coefficient Kmin; when the rotational speed w of the output shaft of the motor unit>wt, the additional compensation torque scheduling module will schedule the additional compensation torque Ta set by the compensation torque module to 0.

5. A robot arm detection control device according to claim 4, characterized in that: The robot arm detection control device also includes: a temperature sensor, which collects temperature data of the motor unit when it is working; a torque detection unit includes a strain gauge module and a detection circuit module, the strain gauge module is installed on the output shaft of the motor unit, the strain gauge module collects strain data of the output shaft of the motor unit, and the strain gauge is connected to the detection circuit module; the control unit includes a strain-torque index module and a calibration module, the strain-torque index module establishes a strain-torque mapping table of the strain value measured by the strain gauge and the calculated torque value; the calibration module compensates and calibrates the strain value measured by the strain gauge to obtain the compensated strain value, and uses the strain-torque mapping table to obtain the actual torque output of the motor unit according to the compensated strain value.

6. A robot arm detection control method, comprising a robot arm detection control device according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step S100: detecting the actual torque signal of the motor unit; Step S200: acquiring the detected actual torque signal of the motor unit, processing and calibrating the actual torque signal to acquire the actual torque output by the motor unit; Step S300: performing zero-force control on the robotic arm according to the actual torque output by the motor unit and the robotic arm compensation torque, wherein the robotic arm compensation torque includes the gravity torque of the robotic arm, the friction torque of the robotic arm joint, and the inertia torque of the robotic arm.

7. A robot arm detection control method according to claim 6, characterized in that: In step S300, performing zero-force control on the robotic arm according to the actual torque output by the motor unit and the robotic arm compensation torque includes: When the rotation speed w≤wt of the output shaft of the motor unit, the additional compensation torque Ta is set, and the first compensation torque ratio △T1 is calculated, △T1=Tp1 / Tq1=Tp1 / (Tg1+Ta+Tm1), and the first compensation torque ratio △T1 is less than or equal to the first preset value P1; or, when the rotation speed w>wt of the output shaft of the motor unit, the second compensation torque ratio △T2 is calculated, △T2=Tp2 / Tq2=Tp2 / (Tg2+Tf+Tm2), and the second compensation torque ratio △T2 is less than or equal to the second preset value P2; Among them, wt is the set speed. When the speed of the output shaft of the motor unit w≤wt, Tp1 is the actual torque output by the motor unit; Tq1 is the sum of the first compensating gravity torque Tg1, the additional compensating torque Ta and the first compensating inertia torque Tm1; Tg1 is the first compensating gravity torque of the robotic arm; Tm1 is the first compensating inertia torque of the robotic arm; when the speed of the output shaft of the motor unit w>wt, Tp2 is the actual torque output by the motor unit; Tq2 is the sum of the second compensating gravity torque Tg2, the compensating friction torque Tf and the second compensating inertia torque Tm2; Tg2 is the second compensating gravity torque of the robotic arm, Tm2 is the second compensating inertia torque of the robotic arm, and Tf is the compensating friction torque of the robotic arm.

8. A robot arm detection control method according to claim 7, characterized in that: In step S300, setting the additional compensation torque Ta includes: Calculate the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the i-th compliance tracking coefficient Ki, ..., the n-th compliance tracking coefficient Kn, satisfying: Ki=|(Tg1+Tai+Tm1)-Tjmax| / Tjmax+|Ta i-Tf| / Tf; Wherein, Tjmax is the maximum static friction torque, which is preset after being obtained through experiments or theoretical derivation, Ta1 is the first additional compensation torque stored in advance, Ta2 is the second additional compensation torque stored in advance, ..., Tai is the third additional compensation torque stored in advance, ..., Tan is the nth additional compensation torque stored in advance, i=1, 2, 3, ..., n, and n is a positive integer; According to the first compliance tracking coefficient K1, the second compliance tracking coefficient K2, ..., the ith compliance tracking coefficient Ki, ..., the nth compliance tracking coefficient Kn, the minimum compliance tracking coefficient Kmin = min[K1, K2, ..., Kn] is obtained, and the additional compensation torque Ta is obtained according to the minimum compliance tracking coefficient Kmin.

9. A robotic arm, comprising the robotic arm detection control device described in any one of claims 1 to 5 or using the robotic arm detection control method described in any one of claims 6 to 8.

10. A robot used for teaching, comprising the robotic arm as claimed in claim 9.

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