Active vibration isolation control method and system

Abstract

The invention provides an active vibration isolation control method and system, and belongs to the technical field of vibration isolation. Firstly, vibration information of the ultra-precision equipment is collected and preprocessed, then preprocessed vibration information data are input into a rectangular integral PID algorithm in a multi-core control system to obtain PID output, and then an actuator is controlled to respond based on the PID output to generate a reverse vibration signal; and finally, obtaining a vibration error of the ultra-precision equipment after vibration isolation so as to determine to adjust a rectangular integral PID algorithm or stop active vibration isolation control. According to the active vibration isolation control method, a multi-core control system is used, the system response speed can be increased, and a more complex control system is compatible; and meanwhile, the rectangular integral PID algorithm improves the large-load active vibration isolation effect, and the algorithm execution efficiency and the system response speed of the active vibration isolation system are both considered.

Description

Technical Field

[0001] This invention belongs to the field of vibration isolation technology, and particularly relates to an active vibration isolation control method and system. Background Technology

[0002] Active vibration isolation control is a method that actively applies a counterforce to counteract vibration by monitoring vibration signals in real time. It is widely used in semiconductor manufacturing, aerospace, and other fields, particularly for active vibration isolation of ultra-precision semiconductor equipment, which can improve equipment performance and ensure industrial automation efficiency. Existing technologies include active vibration isolation methods based on PID control; for example, the literature "PID Model Reference Adaptive Control Technology in Active Vibration Isolation Systems" applies PID control to active vibration isolation systems. However, the derivative term of traditional PID control amplifies high-frequency noise collected by the sensor, resulting in poor effectiveness for active vibration isolation under large loads. Furthermore, the cumulative error of the integral term in traditional PID control can lead to system response delays. In addition, existing technologies typically employ single-core control in the design of active vibration isolation control systems, limiting the execution efficiency of the system algorithm and the system response time. Summary of the Invention

[0003] To address the aforementioned problems in existing technologies, this invention proposes an active vibration isolation control method and system. It employs an improved PID algorithm based on rectangular integrals to at least partially solve the problems of low algorithm execution efficiency, system response delay, and poor vibration isolation effect under large loads in existing active vibration isolation technologies.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: an active vibration isolation control method, comprising the following steps: Step S1: collecting vibration information of ultra-precision equipment to obtain vibration information data; Step S2: importing the vibration information data into a multi-core control system and preprocessing it to obtain preprocessed vibration information data; Step S3: inputting the preprocessed vibration information data into a rectangular integral PID algorithm in the multi-core control system to obtain PID output; Step S4: obtaining control commands for the actuator based on the PID output, and controlling the actuator to respond according to the control commands to generate a reverse vibration signal; Step S5: obtaining the vibration error of the ultra-precision equipment after vibration isolation based on the reverse vibration signal; when the vibration error after vibration isolation does not meet the preset conditions, adjusting the initial parameters of the rectangular integral PID algorithm, and repeating steps S3-S4; when the vibration error after vibration isolation meets the preset conditions, ending the active vibration isolation control.

[0005] Further, in step S2, the vibration information data is imported into the multi-core control system and preprocessed, including: step S21: removing outliers from the vibration information data to obtain the removed vibration information data; step S22: performing anti-aliasing filtering on the removed vibration information data to obtain the preprocessed vibration information data.

[0006] Further, in step S3, the rectangular integral PID algorithm includes: Step S31: Defining the initial parameters of the PID algorithm, the initial parameters including the proportional parameter Kp, the integral parameter Ki, the derivative parameter Kd, and the vibration reference value; Step S32: Calculating the current error error based on the preprocessed vibration information data and the vibration reference value, and obtaining the previous error Lerror; Step S33: Setting the initial moving window Mwindow and the initial integral value I1; Step S34: Calculating the integral update value I2 based on the rectangular integral logic; Step S35: Comparing the absolute value of the difference between I1 and I2 with the size of a preset threshold, when the difference is greater than the preset threshold, adjusting the initial moving window Mwindow to obtain the adjusted moving window, and executing step S34 based on the adjusted moving window; when the difference is less than or equal to the preset threshold, using the integral update value I2 as the final integral update value I2f to obtain the PID output.

[0007] Further, in step S34, the integral update value I2 is calculated based on rectangular integral logic, specifically as follows: Step S341: Perform iterative calculations according to the following logic: ; Where i represents the iteration number, i = 0, 1, ..., round(1 / Mwindow)-1, round represents the rounding function, Mwindow represents the initial moving window, I2 represents the integral update value, and I1 represents the integral update value. i Let I10 represent the iteration variable, k1 represent the first adjustment coefficient, k2 represent the second adjustment coefficient, Lerror represent the previous error, and error represent the current error. Step S342: Transfer the completed iteration I1 i+1 This is the integral update value I2.

[0008] Furthermore, in step S35, adjusting the initial moving window Mwindow specifically involves multiplying the initial moving window Mwindow by a first proportional coefficient kp1 to obtain the adjusted moving window.

[0009] Further, obtaining the PID output in step S35 specifically involves: ; Where OUTpid represents the PID output.

[0010] The present invention also provides an active vibration isolation control system for executing the above-described active vibration isolation control method. The active vibration isolation control system includes a sensor, a multi-core control system, and an actuator. The sensor is connected to the multi-core control system, and the multi-core control system is connected to the actuator.

[0011] The multi-core control system may include an FPGA and a DSP. The FPGA is used to preprocess the vibration information of the ultra-precision equipment acquired by the sensors and send the preprocessed vibration information data to the DSP. The DSP is used to execute the rectangular integral PID algorithm. The multi-core control system may also include an ARM and a DSP. The ARM is used to preprocess the vibration information of the ultra-precision equipment acquired by the sensors and send the preprocessed vibration information data to the DSP. The DSP is used to execute the rectangular integral PID algorithm.

[0012] The beneficial technical effects of this invention compared with the prior art are as follows: (1) Using a multi-core control system based on FPGA and DSP, or ARM and DSP combination, can improve system response speed and be compatible with more complex control systems; (2) The improved PID algorithm based on rectangular integral can smooth the influence of high frequency noise by designing a moving window variable, thereby improving the effect of active vibration isolation under large load; the size of the moving window can be adjusted according to the different error changes, so as to take into account both the algorithm execution efficiency and system response speed of the active vibration isolation system. Attached Figure Description

[0013] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0014] Figure 1 This is a simplified flowchart of the active vibration isolation control method of the present invention; Figure 2 This is a simplified flowchart of the rectangular integral PID algorithm of the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0017] Refer to the instruction manual. Figure 1 The present invention adopts the following technical solution: an active vibration isolation control method, comprising the following steps: Step S1: collecting the operation and control information of the ultra-precision equipment and the ground vibration information of the ultra-precision equipment to determine the vibration information data; Step S2: importing the vibration information data into a multi-core control system and performing preprocessing to obtain preprocessed vibration information data; including: Step S21: removing outliers from the vibration information data based on the 3sigma principle (normal distribution statistics) to obtain removed vibration information data; Step S22: inputting the removed vibration information data into a Butterworth filter (preferably 6th order or higher) to perform anti-aliasing filtering on the removed vibration information data to eliminate the distortion of vibration information data caused by frequency aliasing during sampling, thereby obtaining preprocessed vibration information data.

[0018] Step S3: Input the preprocessed vibration information data into the rectangular integral PID algorithm in the multi-core control system to obtain the PID output; Step S4: Obtain the control command of the actuator based on the PID output, and control the actuator to respond according to the control command to generate a reverse vibration signal to cancel the vibration; Step S5: Obtain the vibration error of the ultra-precision equipment after vibration isolation based on the reverse vibration signal. When the vibration error after vibration isolation does not meet the preset conditions, adjust the initial parameters of the rectangular integral PID algorithm (including proportional parameter Kp, integral parameter Ki, and derivative parameter Kd), and repeat steps S3-S4. When the vibration error after vibration isolation meets the preset conditions, end the active vibration isolation control.

[0019] The following is in conjunction with the instruction manual appendix. Figure 2The steps of the rectangular integral PID algorithm of the present invention are described below. The rectangular integral PID algorithm specifically includes: Step S31: Define the initial parameters of the PID algorithm, including the proportional parameter Kp, the integral parameter Ki, the derivative parameter Kd, and the vibration reference value; Step S32: Calculate the current error error (i.e., subtract the vibration reference value from the preprocessed vibration information data) based on the preprocessed vibration information data and the vibration reference value, and obtain the previous error Lerror, which can be the average error of the previous sampling period; Step S33: Set the initial moving window Mwindow and the initial integral value I1; Step S34: Calculate the integral update value I2 based on the rectangular integral logic; Step S35: Compare the absolute value of the difference between I1 and I2 with the size of a preset threshold. When the difference is greater than the preset threshold, adjust the initial moving window Mwindow to obtain the adjusted moving window, and execute step S34 based on the adjusted moving window; when the difference is less than or equal to the preset threshold, use the integral update value I2 as the final integral update value I2f to obtain the PID output.

[0020] In step S34, the integral update value I2 is calculated based on the rectangular integral logic, specifically as follows: Step S341: Perform iterative calculation according to the following logic: ; Where i represents the iteration number, i = 0, 1, ..., round(1 / Mwindow)-1, round represents the rounding function, Mwindow represents the initial moving window, I2 represents the integral update value, and I1 represents the integral update value. i Let I10 = I1 represent the iteration variable, k1 represent the first adjustment coefficient (preferably a positive number greater than 0 and less than 1), k2 represent the second adjustment coefficient (preferably a positive number greater than 1 and less than 3), Lerror represent the previous error, and error represent the current error; Step S342: Set the I1 after iteration... i+1 This is the integral update value I2.

[0021] Further, in step S35, adjusting the initial moving window Mwindow specifically involves multiplying the initial moving window Mwindow by a first scaling factor kp1 to obtain the adjusted moving window. Preferably, the first scaling factor kp1 is a positive number less than 1 and greater than 0. Through this adjustment of the moving window, a larger moving window is initially used to quickly calculate the integral value, while the moving window is gradually shrunk to address drastic error changes, thus ensuring calculation accuracy while optimizing calculation efficiency.

[0022] Further, obtaining the PID output in step S35 specifically involves: ; Where OUTpid represents the PID output, it can be seen that the above PID output is the sum of the proportional term, integral term and derivative term. The proportional term can respond to the error and adjust the output result, the integral term can eliminate steady-state error, and the derivative term can suppress the overshoot of the output result.

[0023] The present invention also provides an active vibration isolation control system for executing the above-described active vibration isolation control method. The active vibration isolation control system includes a sensor, a multi-core control system, and an actuator. The sensor is connected to the multi-core control system, and the multi-core control system is connected to the actuator.

[0024] The multi-core control system may include an FPGA and a DSP. The FPGA is used to preprocess the vibration information of the ultra-precision equipment acquired by sensors and send the preprocessed vibration information data to the DSP. The DSP is used to execute the rectangular integral PID algorithm. The multi-core control system may also include an ARM and a DSP. The ARM is used to preprocess the vibration information of the ultra-precision equipment acquired by sensors and send the preprocessed vibration information data to the DSP. The DSP is used to execute the rectangular integral PID algorithm. The active vibration isolation control system of the present invention is compatible with different models of ARM, DSP, and FPGA.

[0025] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0026] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. An active vibration isolation control method, characterized in that, Includes the following steps: Step S1: Collect vibration information from the ultra-precision equipment to obtain vibration data; Step S2: Import the vibration information data into the multi-core control system and preprocess it to obtain preprocessed vibration information data; Step S3: In the multi-core control system, the preprocessed vibration information data is input into the rectangular integral PID algorithm to obtain the PID output; Step S4: Obtain the control command for the actuator based on the PID output, and control the actuator to respond according to the control command to generate a reverse vibration signal; Step S5: Obtain the vibration error of the ultra-precision equipment after vibration isolation based on the reverse vibration signal. When the vibration error after vibration isolation does not meet the preset conditions, adjust the initial parameters of the rectangular integral PID algorithm and repeat steps S3-S4. When the vibration error after vibration isolation meets the preset conditions, end the active vibration isolation control.

2. The active vibration isolation control method according to claim 1, characterized in that, Step S2 involves importing the vibration information data into the multi-core control system and performing preprocessing, including: Step S21: Remove outliers from the vibration information data to obtain the removed vibration information data; Step S22: Perform anti-aliasing filtering on the removed vibration information data to obtain preprocessed vibration information data.

3. The active vibration isolation control method according to claim 1, characterized in that, In step S3, the rectangular integral PID algorithm includes: Step S31: Define the initial parameters of the PID algorithm, including the proportional parameter Kp, the integral parameter Ki, the derivative parameter Kd, and the vibration reference value; Step S32: Based on the preprocessed vibration information data and vibration reference values, calculate the current error error and obtain the previous error Lerror; Step S33: Set the initial moving window Mwindow and the initial integral value I1; Step S34: Calculate the integral update value I2 based on rectangular integral logic; Step S35: Compare the absolute value of the difference between I1 and I2 with the size of a preset threshold. When the difference is greater than the preset threshold, adjust the initial moving window Mwindow to obtain the adjusted moving window, and execute step S34 based on the adjusted moving window. When the difference is less than or equal to the preset threshold, use the integral update value I2 as the final integral update value I2f to obtain the PID output.

4. The active vibration isolation control method according to claim 3, characterized in that, The step S34, which calculates the integral update value I2 based on rectangular integral logic, specifically involves: Step S341: Perform iterative calculations according to the following logic: ； Where i represents the iteration number, i = 0, 1, ..., round(1 / Mwindow)-1, round represents the rounding function, Mwindow represents the initial moving window, I2 represents the integral update value, and I1 represents the integral update value. i Let I10 represent the iteration variable, k1 represent the first adjustment coefficient, k2 represent the second adjustment coefficient, Lerror represent the previous error, and error represent the current error. Step S342: Transfer the completed iteration I1 i+1 This is the integral update value I2.

5. The active vibration isolation control method according to claim 4, characterized in that, In step S35, adjusting the initial moving window Mwindow specifically involves multiplying the initial moving window Mwindow by a first proportional coefficient kp1 to obtain the adjusted moving window.

6. The active vibration isolation control method according to claim 5, characterized in that, The PID output is obtained in step S35 as follows: ； Where OUTpid represents the PID output.

7. An active vibration isolation control system, used to execute the active vibration isolation control method according to any one of claims 1-6, characterized in that, The active vibration isolation control system includes a sensor, a multi-core control system, and an actuator. The sensor is connected to the multi-core control system, and the multi-core control system is connected to the actuator.

8. An active vibration isolation control system according to claim 7, characterized in that, The multi-core control system includes an FPGA and a DSP. The FPGA is used to preprocess the vibration information of the ultra-precision equipment acquired by the sensor and send the preprocessed vibration information data to the DSP. The DSP is used to execute the rectangular integral PID algorithm.

9. An active vibration isolation control system according to claim 7, characterized in that, The multi-core control system includes an ARM and a DSP. The ARM is used to preprocess the vibration information of the ultra-precision equipment acquired by the sensor and send the preprocessed vibration information data to the DSP. The DSP is used to execute the rectangular integral PID algorithm.

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