System and method for adjusting force control precision of motor

Abstract

The invention discloses a system and method for adjusting motor force control precision, and belongs to the technical field of electronic equipment testing. The system comprises a pressure amplifier, a pressure sensor, a motor, a motor driver and a force control subsystem, the pressure sensor senses the pressure applied to the to-be-tested device; the pressure amplifier inputs the amplified pressure signal into the force control subsystem; the force control subsystem determines a first control parameter for controlling the motor according to the amplified pressure signal and sends the first control parameter to the control execution unit, and the control execution unit controls the motor driver to drive the motor and adjust the rotating speed and the rotating direction of the motor and the current position of the motor; and enabling the pressure applied to the device to be tested to reach the target pressure value. Technical support is provided for application scenes needing high-precision force control.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic equipment testing, and in particular to a system and method for adjusting the force control accuracy of a motor. Background Art

[0002] When testing products in the computer, communication, consumer electronics, automotive and medical industries, force control testing and monitoring force feedback are required. When performing force control testing, the actuator's continuous force on the test device needs to reach the target value of + / -0.01N accuracy to ensure the accuracy and reliability of the test. However, the current market situation has brought two major challenges to users: First, the traditional motors widely used in the market do not support force control. Second, there is a shortage of motors that support force control, and the important force control accuracy varies. In view of the above, users face many problems such as design adaptation, cost and time when purchasing such products, which significantly increases the difficulty of purchasing and the overall time cost of users. Summary of the invention

[0003] The present invention provides a system and method for adjusting the force control accuracy of a motor, aiming to solve the technical problem that existing traditional motors do not support force control and the force control accuracy of motors that can support force control is insufficient.

[0004] A first aspect of the present invention provides a system for adjusting the force control accuracy of a motor, the system comprising: Pressure amplifier, pressure sensor, motor, motor driver, force control subsystem; The pressure sensor is deployed on the device under test, and after the system for adjusting the motor force control accuracy performs pre-pressure position self-learning, the pressure applied to the device under test is sensed; the pressure amplifier amplifies the pressure signal obtained by the pressure sensor, and the amplified pressure signal is input into the force control subsystem; the force control subsystem determines a first control parameter for controlling the motor according to the amplified pressure signal, and sends the first control parameter to the control execution unit, and the control execution unit controls the motor driver to drive the motor, adjusts the speed, rotation direction and current position of the motor, so that the pressure applied to the device under test reaches the target pressure value; The force control subsystem includes a host computer, a sampling unit, a micro control unit and a control execution unit; The microcontroller unit obtains the sampling signal and the target value set by the host computer, and calls the PID algorithm to output the control parameter; based on the control parameter, a first control parameter for controlling the motor is generated, and the control execution unit drives the motor based on the first control parameter; the sampling signal is obtained based on the amplified pressure signal obtained by the sampling unit; The sampling unit includes a first sampling unit and a second sampling unit, the sampling speed of the first sampling unit is greater than the sampling speed of the second sampling unit; the first sampling unit and the second sampling unit are used selectively, the first sampling unit has a multi-channel analog quantity acquisition interface, and the second sampling unit has a second RS485 communication interface; the sampling unit adjusts the sampling frequency based on the control instruction of the micro control unit; The first sampling unit and the second sampling unit support the coordinated use of multiple pressure amplifiers; when multiple pressure amplifiers are used in coordination, each analog interface of the first sampling unit can be connected to a pressure amplifier for amplifying pressure; the second RS485 communication interface of the second sampling unit can expand multiple connection paths, each connection path is used to connect a pressure amplifier for amplifying pressure.

[0005] According to the system of the first aspect of the present invention, the motor performs preload position self-learning after the system for adjusting the motor force control accuracy is initialized. The preload position self-learning is performed in the following manner: The host computer sends a self-learning bias value set by the user to the microcontroller unit, and then sends a pre-stress position self-learning instruction. The system for adjusting the motor force control accuracy controls the motor to start running, and obtains the value of the pressure amplifier in real time. When it is detected that the value of the pressure amplifier is equal to or greater than 1N, it is determined that the pressure head of the mechanism connected to the motor has contacted the device to be tested, and the motor is adjusted to a position with a deviation less than a preset threshold, and the preset threshold is 1N; after the system for adjusting the motor force control accuracy determines that the value of the pressure amplifier is within the preset threshold for 10 consecutive times, the position value corresponding to the current position of the motor minus the self-learning bias value is used as the pre-stress position value, and the position corresponding to the pre-stress position value is used as the pre-stress position.

[0006] According to the system of the first aspect of the present invention, the control execution unit includes multiple pulse interfaces and a first RS485 communication interface, and the motor is connected to one of the multiple pulse interfaces or to the first RS485 communication interface; the control execution unit controls the motor driver to drive the motor based on the first control parameter, and feeds back the current state of the motor to the micro control unit.

[0007] According to the system of the first aspect of the present invention, the microcontroller unit samples the amplified pressure signal obtained by the sampling unit to obtain a sampling signal; the target value set by the host computer includes a target pressure value, a target pre-pressure position, a parameter that needs to be adjusted by the PID algorithm, and a self-learning bias value; the microcontroller unit calls the PID algorithm, and determines a control increment based on the sampling signal and the target value set by the host computer, and determines a control parameter based on the control increment; generates a first control parameter for controlling the motor based on the control parameter, and sends the first control parameter to the control execution unit; The host computer is connected to the micro control unit via the USB port of the micro control unit, and the host computer sends the parameters set by the user and the remote control instructions to the micro control unit; the parameters set by the user are the target values ​​set by the host computer.

[0008] According to the system of the first aspect of the present invention, the system for adjusting the motor force control accuracy is initialized in the following manner: The pulse parameters of the control execution unit are configured, and the pulse parameters include the pulse type, frequency, width, duty cycle and phase difference of the motor driver; the control execution unit uses the RS485 Modbus RTU protocol to configure the first RS485 parameter of the control execution unit, and the first RS485 parameter includes the baud rate, site ID address, displacement register, return register, current position register, disable and enable register of the motor driver; Using the RS485 Modbus RTU protocol, configure the second RS485 parameters of the second sampling unit, wherein the second RS485 parameters include the baud rate of the pressure amplifier, the site ID address, the current pressure value register, the pressure value reset register, and the sampling rate output register; The PID algorithm preset parameters are configured in the host computer, and the PID algorithm preset parameters include a P proportional coefficient preset value, an I integral coefficient preset value, and a D differential coefficient preset value.

[0009] Preferably, the PID algorithm is:

[0010] in, To control the increment, k is the current number of iterations, is the error corresponding to k iterations, is the error corresponding to k-1 iterations, is the error corresponding to k-2 iterations, , , These are the parameters that need to be adjusted by the PID algorithm. is the P proportionality coefficient, is the I integral coefficient, is the D proportionality coefficient; , is the target pressure value, The pressure sensor value obtained for the pressure amplifier.

[0011] A second aspect of the present invention provides a method for adjusting the force control accuracy of a motor. Based on the system for adjusting the force control accuracy of a motor as described above, the method includes: The user uses the host computer to issue a force control instruction, and the system for adjusting the motor force control accuracy drives the motor, adjusts the motor speed, rotation direction and current position of the motor, so that the pressure applied to the device under test reaches the target pressure value; Obtain force control test data of the device under test.

[0012] The present invention provides a computer-readable storage medium, wherein a plurality of instructions are stored in the computer-readable storage medium; the plurality of instructions are used for a processor to load and execute the method described in the first aspect of the present invention.

[0013] An electronic device provided by the present invention is characterized in that the electronic device comprises: A processor, which is used to execute multiple instructions; A memory for storing a plurality of instructions; The plurality of instructions are used to be stored by the memory, and loaded and executed by the processor according to the method described in the first aspect of the present invention.

[0014] The beneficial technical effects brought by the present invention include: (1) The present invention realizes the adaptation and compatibility of motors supporting pulse and RS485 communication protocols and pressure amplifiers with analog interfaces, thereby greatly broadening the user's choice range and reducing the inconvenience and cost burden caused by manufacturer restrictions; (2) The present invention not only supports standard pulse and 485 communication interfaces, but also provides abundant interface resources, greatly facilitating users’ secondary development and customization needs. The present invention achieves cost control while ensuring high performance, providing users with a highly cost-effective force control solution.

[0015] (3) The present invention adopts the PID algorithm, which ensures the stable force control accuracy can reach + / -0.01N of the target value through precise algorithm tuning and hardware design, providing strong technical support for application scenarios that require high-precision force control (such as precision manufacturing, automated assembly lines, experimental equipment, etc.). BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A test schematic diagram of a system for adjusting the motor force control accuracy according to the present invention.

[0017] Figure 2 Schematic diagram of the structure of the system for adjusting the motor force control accuracy according to the present invention. DETAILED DESCRIPTION

[0018] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0019] like Figure 1 As shown, the present invention proposes a system for adjusting the force control accuracy of a motor, comprising: Pressure amplifier, pressure sensor, motor, motor driver, force control subsystem; The pressure sensor is deployed on the device under test, and after the system for adjusting the motor force control accuracy performs pre-pressure position self-learning, the pressure applied to the device under test is sensed; the pressure amplifier amplifies the pressure signal obtained by the pressure sensor, and the amplified pressure signal is input into the force control subsystem; the force control subsystem determines a first control parameter for controlling the motor according to the amplified pressure signal, and sends the first control parameter to the control execution unit, and the control execution unit controls the motor driver to drive the motor, adjusts the speed, rotation direction and current position of the motor, so that the pressure applied to the device under test reaches the target pressure value; The force control subsystem includes a host computer, a sampling unit, a micro control unit and a control execution unit; The microcontroller unit obtains the sampling signal and the target value set by the host computer, and calls the PID algorithm to output the control parameter; based on the control parameter, a first control parameter for controlling the motor is generated, and the control execution unit drives the motor based on the first control parameter; the sampling signal is obtained based on the amplified pressure signal obtained by the sampling unit.

[0020] Furthermore, the control execution unit includes a plurality of pulse interfaces and a first RS485 communication interface, and the motor is connected to one of the plurality of pulse interfaces or to the first RS485 communication interface; the control execution unit controls the motor driver to drive the motor based on the first control parameter, and feeds back the current state of the motor to the micro control unit; The sampling unit includes a first sampling unit and a second sampling unit, the sampling speed of the first sampling unit is greater than the sampling speed of the second sampling unit; the first sampling unit and the second sampling unit are used selectively, the first sampling unit has a multi-channel analog quantity acquisition interface, and the second sampling unit has a second RS485 communication interface; when the first sampling unit is selected, the pressure amplifier is connected to one of the multi-channel analog quantity acquisition interfaces; when the second sampling unit is selected, the pressure amplifier is connected to the second RS485 communication interface; the sampling unit adjusts the sampling frequency based on the control instruction of the micro control unit; The microcontroller unit samples the amplified pressure signal obtained by the sampling unit to obtain a sampling signal; the target value set by the host computer includes a target pressure value, a target pre-pressure position, parameters that need to be adjusted by the PID algorithm, and a self-learning bias value; the microcontroller unit calls the PID algorithm, and determines a control increment based on the sampling signal and the target value set by the host computer, and determines a control parameter based on the control increment; generates a first control parameter for controlling the motor based on the control parameter, and sends the first control parameter to the control execution unit; The host computer is connected to the micro control unit via the USB port of the micro control unit, and the host computer sends the parameters set by the user and the remote control instructions to the micro control unit; the parameters set by the user are the target values ​​set by the host computer.

[0021] Furthermore, the system for adjusting the motor force control accuracy supports coordinated control of multiple motors; when multiple motors are coordinated, each pulse interface of the control execution unit can be connected to one motor for motor force control; the first RS485 communication interface can expand multiple connection paths, each connection path is used to connect a motor for motor force control or other motor control. Furthermore, the first sampling unit and the second sampling unit support the coordinated use of multi-channel pressure amplifiers; when the multi-channel pressure amplifiers are used in coordination, each analog interface of the first sampling unit can be connected to a pressure amplifier for amplifying pressure; the second RS485 communication interface of the second sampling unit can expand multiple connection paths, each connection path is used to connect a pressure amplifier for amplifying pressure. The purpose of setting up the sampling unit of the present invention is to select a specific sampling unit according to actual use needs, and the two sampling units are designed to provide multiple expansion interfaces to realize the use and expansion of the multi-channel pressure amplifier, thereby realizing the amplification of small pressure values ​​and high-precision pressure.

[0022] In this embodiment, the control execution unit provides multiple pulse interfaces and a first RS485 communication interface, so that it can adapt to a variety of motors. Users can choose the connection method according to actual needs, ensuring the diversity and wide adaptability of the motor control method, and meeting the user's single-channel and multi-channel motor pulse control usage scenarios. There are 4 pulse interfaces, which can support simultaneous force control of 4 motors. The first RS485 communication interface supports the expansion of a maximum of 4 motors for force control. In non-force control scenarios, the pulse interface can also support conventional control of 4 motors, and the first RS48 communication interface supports the expansion of conventional control of a maximum of 32 motors.

[0023] The first sampling unit and the second sampling unit also enable users to freely select the interface of the pressure amplifier according to actual needs and application scenarios. This ensures the diversity and wide adaptability of the pressure amplifier control method. For example, the first sampling unit supports 4-channel pressure amplifier output analog quantity acquisition (2-channel differential or 4-channel pseudo-differential input), meeting the user's single-channel and multi-channel use scenarios that require high sampling rates; The second RS485 communication interface of the second sampling unit supports expansion of a maximum of 4 pressure amplifier accesses for force control, and supports expansion of a maximum of 32 accesses in non-force control scenarios.

[0024] The pressure amplifier is calibrated before use, and the calibration method of the pressure amplifier is as follows: Select a pressure sensor based on the test requirements. The total range of the pressure sensor should be greater than or equal to twice the maximum pressure expected to be applied by the device under test. The pressure sensor was calibrated using a standard weight.

[0025] The initialization method of the system for adjusting the motor force control accuracy is: The pulse parameters of the control execution unit are configured, and the pulse parameters include the pulse type, frequency, width, duty cycle and phase difference of the motor driver; the control execution unit uses the RS485 Modbus RTU protocol to configure the first RS485 parameter of the control execution unit, and the first RS485 parameter includes the baud rate, site ID address, displacement register, return register, current position register, disable and enable register of the motor driver; Using the RS485 Modbus RTU protocol, configure the second RS485 parameters of the second sampling unit, wherein the second RS485 parameters include the baud rate of the pressure amplifier, the site ID address, the current pressure value register, the pressure value reset register, and the sampling rate output register; The PID algorithm preset parameters are configured in the host computer, and the PID algorithm preset parameters include a P proportional coefficient preset value, an I integral coefficient preset value, and a D differential coefficient preset value.

[0026] After the system for adjusting the force control accuracy of the motor is initialized, the motor performs self-learning of the pre-stress position, and the pre-stress position is the contact position between the pressure head of the mechanism connected to the motor and the device under test. The purpose of self-learning the pre-stress position is to allow the system for adjusting the force control accuracy of the motor to obtain and save the pre-stress position. Before the force control process, the system for adjusting the force control accuracy of the motor first calls the pre-stress position to allow the motor connection pressure head to quickly reach the pre-stress position of the device under test, and then enters the force control process to improve the execution efficiency of the entire action cycle.

[0027] The method of self-learning the preload position is: The host computer sends the self-learning bias value set by the user to the microcontroller unit, and then sends a pre-stress position self-learning instruction. The system for adjusting the motor force control accuracy controls the motor to start running, and obtains the value of the pressure amplifier in real time. When it is detected that the value of the pressure amplifier is equal to or greater than 1N, it is determined that the pressure head of the mechanism connected to the motor has contacted the device to be tested, and the motor is adjusted to a position with a deviation less than a preset threshold value, and the preset threshold value is 1N; after the system for adjusting the motor force control accuracy determines that the value of the pressure amplifier is within the preset threshold value for 10 consecutive times, the position value corresponding to the current position of the motor is subtracted from the self-learning bias value as the pre-stress position value, and the position corresponding to the pre-stress position value is used as the pre-stress position. The self-learning mechanism of the present invention is carried out through the self-learning bias value set by the host computer. The above-mentioned pre-stress position self-learning method can achieve high-precision pressure regulation, so that the continuous force of the actuator on the test device reaches the target value with an accuracy of + / -0.01N.

[0028] In the present invention, after the self-learning of the pre-compression position is completed, the system for adjusting the motor force control accuracy can directly obtain the pre-compression position when it is used subsequently, without the need to repeat the learning of the pre-compression position.

[0029] The PID algorithm is:

[0030] in, To control the increment, k is the current number of iterations, is the error corresponding to k iterations, is the error corresponding to k-1 iterations, is the error corresponding to k-2 iterations, , , These are the parameters that need to be adjusted by the PID algorithm. is the P proportionality coefficient, is the I integral coefficient, is the D proportionality coefficient; , is the target pressure value, The pressure sensor value obtained for the pressure amplifier.

[0031] In the present invention, the micro-control unit controls the increment The control execution unit adjusts the current position of the motor so that the pressure value acting on the device under test approaches .

[0032] The present invention also provides a method for adjusting the force control accuracy of a motor. Based on the system for adjusting the force control accuracy of a motor as described above, the method comprises: The user uses the host computer to issue a force control instruction, and the system for adjusting the motor force control accuracy drives the motor, adjusts the motor speed, rotation direction and current position of the motor, so that the pressure applied to the device under test reaches the target pressure value; Obtain force control test data of the device under test.

[0033] The above specific embodiments only describe the design principle of the present invention. The shapes and names of the components in the description may be different and are not limited. Therefore, those skilled in the art in the field of the present invention may modify or replace the technical solutions recorded in the above embodiments; and these modifications and replacements do not deviate from the creative purpose and technical solutions of the present invention and should all fall within the protection scope of the present invention.

Claims

1. A system for adjusting the force control accuracy of a motor, characterized in that: The system comprises: Pressure amplifier, pressure sensor, motor, motor driver, force control subsystem; The pressure sensor is deployed on the device under test, and after the system for adjusting the motor force control accuracy performs pre-pressure position self-learning, the pressure applied to the device under test is sensed; the pressure amplifier amplifies the pressure signal obtained by the pressure sensor, and the amplified pressure signal is input into the force control subsystem; the force control subsystem determines a first control parameter for controlling the motor according to the amplified pressure signal, and sends the first control parameter to the control execution unit, and the control execution unit controls the motor driver to drive the motor, adjusts the speed, rotation direction and current position of the motor, so that the pressure applied to the device under test reaches the target pressure value; The force control subsystem includes a host computer, a sampling unit, a micro control unit and a control execution unit; The microcontroller unit obtains the sampling signal and the target value set by the host computer, and calls the PID algorithm to output the control parameter; based on the control parameter, a first control parameter for controlling the motor is generated, and the control execution unit drives the motor based on the first control parameter; the sampling signal is obtained based on the amplified pressure signal obtained by the sampling unit; The sampling unit includes a first sampling unit and a second sampling unit, the sampling speed of the first sampling unit is greater than the sampling speed of the second sampling unit; the first sampling unit and the second sampling unit are used selectively, the first sampling unit has a multi-channel analog quantity acquisition interface, and the second sampling unit has a second RS485 communication interface; the sampling unit adjusts the sampling frequency based on the control instruction of the micro control unit; The first sampling unit and the second sampling unit support the coordinated use of multiple pressure amplifiers; when multiple pressure amplifiers are used in coordination, each analog interface of the first sampling unit can be connected to a pressure amplifier for amplifying pressure; the second RS485 communication interface of the second sampling unit can expand multiple connection paths, each connection path is used to connect a pressure amplifier for amplifying pressure.

2. The system according to claim 1, characterized in that After the system for adjusting the motor force control accuracy is initialized, the motor performs preload position self-learning, and the preload position self-learning method is: The host computer sends a self-learning bias value set by the user to the microcontroller unit, and then sends a pre-stress position self-learning instruction. The system for adjusting the motor force control accuracy controls the motor to start running, and obtains the value of the pressure amplifier in real time. When it is detected that the value of the pressure amplifier is equal to or greater than 1N, it is determined that the pressure head of the mechanism connected to the motor has contacted the device to be tested, and the motor is adjusted to a position with a deviation less than a preset threshold, and the preset threshold is 1N; after the system for adjusting the motor force control accuracy determines that the value of the pressure amplifier is within the preset threshold for 10 consecutive times, the position value corresponding to the current position of the motor minus the self-learning bias value is used as the pre-stress position value, and the position corresponding to the pre-stress position value is used as the pre-stress position.

3. The system according to claim 1, characterized in that The control execution unit includes multiple pulse interfaces and a first RS485 communication interface, and the motor is connected to one of the multiple pulse interfaces or to the first RS485 communication interface; the control execution unit controls the motor driver to drive the motor based on the first control parameter, and feeds back the current state of the motor to the micro control unit.

4. The system according to claim 1, characterized in that The microcontroller unit samples the amplified pressure signal obtained by the sampling unit to obtain a sampling signal; the target value set by the host computer includes a target pressure value, a target pre-pressure position, parameters that need to be adjusted by the PID algorithm, and a self-learning bias value; the microcontroller unit calls the PID algorithm, and determines a control increment based on the sampling signal and the target value set by the host computer, and determines a control parameter based on the control increment; generates a first control parameter for controlling the motor based on the control parameter, and sends the first control parameter to the control execution unit; The host computer is connected to the micro control unit via the USB port of the micro control unit, and the host computer sends the parameters set by the user and the remote control instructions to the micro control unit; the parameters set by the user are the target values ​​set by the host computer.

5. The system according to claim 1, wherein: The initialization method of the system for adjusting the motor force control accuracy is: The pulse parameters of the control execution unit are configured, and the pulse parameters include the pulse type, frequency, width, duty cycle and phase difference of the motor driver; the control execution unit uses the RS485 Modbus RTU protocol to configure the first RS485 parameter of the control execution unit, and the first RS485 parameter includes the baud rate, site ID address, displacement register, return register, current position register, disable and enable register of the motor driver; Using the RS485 Modbus RTU protocol, configure the second RS485 parameters of the second sampling unit, wherein the second RS485 parameters include the baud rate of the pressure amplifier, the site ID address, the current pressure value register, the pressure value reset register, and the sampling rate output register; The PID algorithm preset parameters are configured in the host computer, and the PID algorithm preset parameters include a P proportional coefficient preset value, an I integral coefficient preset value, and a D differential coefficient preset value.

6. The system according to any one of claims 1 to 5, characterized in that: The PID algorithm is: in, To control the increment, k is the current number of iterations, is the error corresponding to k iterations, is the error corresponding to k-1 iterations, is the error corresponding to k-2 iterations, , , These are the parameters that need to be adjusted by the PID algorithm. is the P proportionality coefficient, is the I integral coefficient, is the D proportionality coefficient; , is the target pressure value, The pressure sensor value obtained for the pressure amplifier.

7. A method for adjusting the force control accuracy of a motor, based on a system for adjusting the force control accuracy of a motor as claimed in any one of claims 1 to 6, characterized in that: The method comprises: The user uses the host computer to issue a force control instruction, and the system for adjusting the motor force control accuracy drives the motor, adjusts the motor speed, rotation direction and current position of the motor, so that the pressure applied to the device under test reaches the target pressure value; Obtain force control test data of the device under test.

8. A computer-readable storage medium, characterized in that: The storage medium stores a plurality of instructions; the plurality of instructions are used for the processor to load and execute the method as claimed in claim 7.

9. An electronic device, characterized in that: The electronic device comprises: A processor, which is used to execute multiple instructions; A memory for storing a plurality of instructions; Wherein, the multiple instructions are used to be stored by the memory, and loaded and executed by the processor as described in claim 7.

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