CN-121979312-A - Method and system for adjusting holding pressure

CN121979312ACN 121979312 ACN121979312 ACN 121979312ACN-121979312-A

Abstract

The embodiment of the invention provides a pressure maintaining pressure adjusting method, which is applied to an upper computer and a servo driver, and comprises the steps that the upper computer configures mapping parameters of a pressure value and an analog value and sends the mapping parameters to the servo driver, and the servo driver controls a servo motor to execute self-learning to determine a contact point origin machine of a pressing process based on a linear calibration model; the upper computer reads the process data packet through the Modbus bus and analyzes the process data packet to obtain a pressure-time relation waveform chart, and based on the built-in high-precision calibration and closed-loop force control of the driver, the servo driver realizes the complete synchronous acquisition and tracing of the process data through the cooperation of the double buses, thereby improving the precision, stability and analyzability of the pressure maintaining process.

Inventors

SUN FENG
JIN HUI

Assignees

苏州赛腾精密电子股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260122

Claims (10)

1. The method for adjusting the holding pressure is applied to an upper computer and a servo driver, and comprises the following steps: the upper computer configures mapping parameters of the pressure value and the analog value and sends the mapping parameters to the servo driver so as to establish a linear calibration model in the servo driver; The servo driver controls the servo motor to execute self-learning point searching operation based on the linear calibration model so as to determine a contact point origin of the pressing process and feed back the contact point origin to the upper computer; the upper computer transmits a force control instruction containing a target pressure value to the servo driver through an EtherCAT bus; the servo driver converts an analog quantity signal fed back by the pressure sensor based on the linear calibration model to obtain a real-time pressure value, compares the real-time pressure value with the target pressure value by taking the origin of the contact point as a reference, adjusts the torque of the servo motor according to a comparison result, and feeds back a state to the upper computer through an EtherCAT (Ethernet control for industrial automation technology) bus; And the upper computer circularly reads the process data packet from the servo driver through the Modbus bus and analyzes the process data packet to obtain a pressure-time relation oscillogram.
2. The method according to claim 1, wherein the method further comprises: and after the pressing cycle is finished, the upper computer stores the process data packet and the corresponding pressure-time relation oscillogram as a structured data file.
3. The method of claim 1, wherein the step of configuring the mapping parameters of the pressure value and the analog value by the host computer specifically comprises: setting two groups of set values in the upper computer through LabVIEW so that the pressure feedback resolution in the servo driver is in the range of 0.1g to 1g, wherein the two groups of set values comprise a first set group and a second set group, the first set group comprises a first pressure set value and a first analog set value, and the second set group comprises a second pressure set value and a second analog set value; And the servo driver establishes a linear mapping function between the pressure and the analog quantity signal according to the two groups of set values.
4. The method of claim 1, wherein controlling the servo motor to perform a self-learning point finding operation to determine a point of origin of a contact point of a lamination process comprises: And controlling the servo motor to press down at a preset low speed, monitoring a pressure value obtained by conversion of the linear calibration model, and recording the current servo motor position as a contact point origin of the pressing process when the monitored pressure value reaches or exceeds a preset landing threshold for the first time.
5. The method of claim 1, wherein the host computer issues a force control command containing a target pressure value to the servo driver via an EtherCAT bus, specifically comprising: In the pressing preparation stage, the upper computer writes force control mode parameters into the servo driver through the EtherCAT bus and starts a force control process sequence, wherein the force control mode parameters at least comprise target pressure values.
6. The method of claim 1, wherein adjusting the servo motor torque according to the comparison result while feeding back the state to the upper computer through the EtherCAT bus comprises: And the servo driver calculates a control quantity according to a comparison result of the real-time pressure value and the target pressure value through a built-in PID algorithm, adjusts the torque of the servo motor according to the control quantity, and periodically feeds back the motor state through an EtherCAT bus.
7. The method of claim 2, wherein the process data packet includes at least a time stamp, a target pressure value, a real-time feedback pressure value, and a servo motor status word.
8. The method of claim 1, wherein after analyzing the process data packet to obtain a pressure-time relationship waveform, further comprising: in the pressing and pressure maintaining stage, the upper computer calculates the pressure fluctuation statistical characteristic of the pressure-time relation oscillogram; when the upper computer judges that the pressure fluctuation statistical characteristic is lower than a preset stability threshold, the upper computer sends a pressure maintaining ending instruction to the servo driver through an EtherCAT bus; And the servo driver responds to the pressure maintaining ending instruction to stop pressure maintaining timing and force control output.
9. The method of claim 1, wherein prior to first performing the controlling the servo motor to perform a self-learning point finding operation, the method comprises: The upper computer issues a testing force control instruction to the servo driver through a Modbus bus; The servo driver responds to the testability force control instruction, performs pressure establishment and release circulation, and feeds back a real-time pressure value and a corresponding motor current value in the circulation process to the upper computer as a test data packet; and the upper computer calculates PID parameters through an offline identification algorithm based on the test data packet, and updates the PID parameters into a built-in PID algorithm of the servo driver.
10. A packing pressure adjustment system, comprising: the upper computer is operated with a LabVIEW program; the servo driver is connected with the upper computer through an Ethernet, wherein the Ethernet connection bears EtherCAT protocol communication and Modbus TCP protocol communication; the host computer configured to perform the steps performed by the host computer in the method of any one of claims 1-9; the servo drive is configured to perform the steps performed by the servo drive in the method of any one of claims 1-9.

Description

Method and system for adjusting holding pressure Technical Field The invention relates to the technical field of industrial automation control, in particular to a method and a system for adjusting the holding pressure. Background In the field of high-precision automated manufacturing, such as precision electronic component assembly, semiconductor packaging, and air tightness detection, the application of controllable and stable pressure maintaining force to a workpiece is a core requirement for ensuring product performance and consistency. The traditional force control method mainly depends on mechanical structure limit, pneumatic pressure or simple electrical switch control, and has the problems of low control precision, incapability of dynamically adjusting force values, difficulty in quantitative traceability of process parameters and the like, and difficulty in meeting the high standard of modern industry on process precision and traceability. In order to improve the control precision, the related technical scheme adopts a mode of combining a pressure sensor and a servo motor, an upper computer sends a position or speed instruction to a servo driver through an analog quantity, meanwhile, analog signals of the pressure sensor are collected, PID (Proportional-Integral-DERIVATIVE CONTROLLER) operation is carried out in upper computer software, and then the calculated correction quantity is added to an original instruction. Such control loops span multiple hardware levels and communication interfaces, and the system delay is large, making real-time closed-loop regulation difficult to achieve in a true sense. In addition, the instruction stream for real-time control and the process data stream for monitoring and recording in the related art are generally mixed in the same communication channel, which may result in poor synchronization of data recording and control, and failure to completely and accurately reproduce the whole process of force control, thus causing difficulties for subsequent process analysis and quality tracing. Disclosure of Invention In view of the above-mentioned problems, a method for adjusting a holding pressure is proposed to overcome or at least partially solve the problems of the related art, and the method is applied to a host computer and a servo driver, and includes: the upper computer configures mapping parameters of the pressure value and the analog value and sends the mapping parameters to the servo driver so as to establish a linear calibration model in the servo driver; The servo driver controls the servo motor to execute self-learning point searching operation based on the linear calibration model so as to determine a contact point origin of the pressing process and feed back the contact point origin to the upper computer; the upper computer transmits a force control instruction containing a target pressure value to the servo driver through an EtherCAT bus; the servo driver converts an analog quantity signal fed back by the pressure sensor based on the linear calibration model to obtain a real-time pressure value, compares the real-time pressure value with the target pressure value by taking the origin of the contact point as a reference, adjusts the torque of the servo motor according to a comparison result, and feeds back a state to the upper computer through an EtherCAT (Ethernet control for industrial automation technology) bus; and the upper computer circularly reads a process data packet containing a time stamp and a pressure value from the servo driver through a Modbus bus, and analyzes the process data packet to obtain a pressure-time relation oscillogram. In an alternative embodiment of the invention, the method further comprises: and after the pressing cycle is finished, the upper computer stores the process data packet and the corresponding pressure-time relation oscillogram as a structured data file. In an optional embodiment of the present invention, the step of configuring, by the upper computer, a mapping parameter of a pressure value and an analog value specifically includes: setting two groups of set values in the upper computer through LabVIEW so that the pressure feedback resolution in the servo driver is in the range of 0.1g to 1g, wherein the two groups of set values comprise a first set group and a second set group, the first set group comprises a first pressure set value and a first analog set value, and the second set group comprises a second pressure set value and a second analog set value; And the servo driver establishes a linear mapping function between the pressure and the analog quantity signal according to the two groups of set values. In an alternative embodiment of the present invention, the controlling the servo motor to perform a self-learning point seeking operation to determine a point of origin of a contact point of a lamination process includes: And controlling the servo motor to press down at a preset low speed, monitoring a pressure va