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CN-122015745-A - Nonlinear periodic error correction method of displacement sensor and displacement sensor

CN122015745ACN 122015745 ACN122015745 ACN 122015745ACN-122015745-A

Abstract

The application discloses a nonlinear periodic error correction method of a displacement sensor and the displacement sensor, wherein in the method, an error acquisition range is an actual displacement range of the displacement sensor in a plurality of repeated periods, the displacement value is calculated at equal intervals according to a theoretical measuring range, and a plurality of corresponding error data are acquired; performing Fourier transformation on the error data to obtain a plurality of groups of harmonic parameters, wherein each group comprises harmonic frequency, harmonic amplitude and harmonic phase, sorting the harmonic parameters according to the magnitude of the harmonic amplitude, selecting a plurality of groups of harmonic parameters corresponding to larger amplitude to establish an error mathematical model, calculating an error value corresponding to any original displacement value based on the model, and correcting the original displacement value according to the error value to obtain a corrected target displacement value. According to the technical scheme, the nonlinear periodic error can be effectively compensated, the output precision of the displacement sensor is improved, and meanwhile, the dependence on a manufacturing process is reduced. The application can be widely applied to the technical field of sensors.

Inventors

  • WANG QIANG
  • YU HUI
  • HU SHUAI
  • TANG XIUQING
  • LEI QUN

Assignees

  • 广州市昊志测量仪器有限公司

Dates

Publication Date
20260512
Application Date
20260121

Claims (10)

  1. 1. A nonlinear periodic error correction method of a displacement sensor is characterized in that an error acquisition range is an actual displacement range of the displacement sensor in a plurality of repeated periods, and the method comprises the following steps: Calculating an equidistant displacement value of the actual displacement range according to a theoretical measuring range, and collecting a plurality of error data corresponding to the displacement sensor; performing Fourier transform on the error data to obtain a plurality of groups of harmonic parameters, wherein each group of harmonic parameters comprises harmonic frequency, harmonic amplitude and harmonic phase; Sorting the harmonic parameters according to the magnitude of the harmonic amplitude, and selecting a plurality of groups of harmonic parameters corresponding to the harmonic amplitude with larger magnitude to establish an error mathematical model; Calculating an error value corresponding to any original displacement value based on the error mathematical model; and correcting the original displacement value according to the error value to obtain a corrected target displacement value.
  2. 2. The method for correcting nonlinear periodic errors of a displacement sensor according to claim 1, wherein the error acquisition range is an actual displacement range of the displacement sensor in p repetition periods, wherein p is a positive integer, the actual displacement range of the displacement sensor in the kth repetition period is [ 0], K is a positive integer and less than or equal to p, , For the theoretical range of the displacement sensor at each of the repetition periods, For the error value at full scale for the kth repetition period, L is the full range of the displacement sensor.
  3. 3. The method for correcting nonlinear periodic errors of a displacement sensor according to claim 2, wherein the method comprises the steps of: Calculating the equidistant displacement value of the actual displacement range according to a theoretical measuring range, and collecting a plurality of error data corresponding to the displacement sensor, wherein the method comprises the following steps: calculating equal interval displacement values according to the theoretical measuring range in the actual displacement range of the kth repetition period, and collecting m error data, wherein m is an even number greater than or equal to 2, and the equal interval displacement values corresponding to the m error data of the kth repetition period are respectively 0, 、 ... ; The error data is subjected to Fourier transformation to obtain a plurality of groups of harmonic parameters, including Performing Fourier transform on M error data to obtain M 1 groups of harmonic parameters, wherein M 1 =m/2, and the harmonic parameters comprise harmonic frequencies Harmonic amplitude Harmonic phase ; The harmonic parameters are ordered according to the magnitude of the harmonic amplitude, a plurality of groups of harmonic parameters corresponding to the harmonic amplitude with larger magnitude are selected to establish an error mathematical model, and the method comprises the following steps: the M 1 groups of harmonic parameters are processed according to the harmonic amplitude Sequencing from large to small, taking the first n 1 groups of harmonic parameters to establish an error mathematical model of a plurality of repetition period errors, and setting up any original displacement value in the kth repetition period Corresponding error value Determined by the following mathematical model of error: Wherein, the The value range of (2) is [ 0], ; The original displacement value is corrected according to the error value, and a corrected target displacement value is obtained, which comprises the following steps: The corrected target displacement value is determined by the following formula: ; In the formula, Is the corrected target displacement value.
  4. 4. The method for correcting nonlinear periodic errors of a displacement sensor according to claim 2, wherein the method comprises the steps of: Calculating the equidistant displacement value of the actual displacement range according to a theoretical measuring range, and collecting a plurality of error data corresponding to the displacement sensor, wherein the method comprises the following steps: Calculating equidistant displacement values according to the theoretical measuring range in the actual displacement ranges of p repetition periods, and collecting m error data to obtain error data with total q, wherein m is an even number greater than or equal to 2, and the equidistant displacement values corresponding to the m error data of each repetition period are respectively 0, 、 ... ,q=mp; The error data is subjected to Fourier transformation to obtain a plurality of groups of harmonic parameters, including Respectively summing error data corresponding to the equal interval displacement values of each repetition period to obtain m errors and data; Performing Fourier transform on the M errors and the data to obtain M 2 groups of harmonic parameters, wherein M 2 =m/2, and the harmonic parameters comprise harmonic frequencies Harmonic amplitude Harmonic phase ; The harmonic parameters are ordered according to the magnitude of the harmonic amplitude, a plurality of groups of harmonic parameters corresponding to the harmonic amplitude with larger magnitude are selected to establish an error mathematical model, and the method comprises the following steps: the M 2 groups of harmonic parameters are processed according to the harmonic amplitude Sequencing from large to small, taking the first n 2 groups of harmonic parameters to establish an error mathematical model of a plurality of repetition period errors, and setting up any original displacement value in each repetition period Corresponding error value Determined by the following mathematical model of error: Wherein the original displacement value in the kth repetition period The value range of (2) is [ 0], ; The original displacement value is corrected according to the error value, and a corrected target displacement value is obtained, which comprises the following steps: The corrected target displacement value is determined by the following formula: ; In the formula, Is the corrected target displacement value.
  5. 5. The method for correcting nonlinear periodic errors of a displacement sensor according to claim 2, wherein the method comprises the steps of: Calculating the equidistant displacement value of the actual displacement range according to a theoretical measuring range, and collecting a plurality of error data corresponding to the displacement sensor, wherein the method comprises the following steps: Calculating equidistant displacement values according to the theoretical measuring range in the actual displacement ranges of p repetition periods, and collecting m error data to obtain error data with total q, wherein m is an even number greater than or equal to 2, and the equidistant displacement values corresponding to the m error data of each repetition period are respectively 0, 、 ... ,q=mp; The error data is subjected to Fourier transformation to obtain a plurality of groups of harmonic parameters, including Respectively summing error data corresponding to the equal interval displacement values of each repetition period to obtain m errors and data; Taking p times of average for each error and data to obtain error and average data; performing Fourier transform on M errors and average data to obtain M 3 groups of harmonic parameters, wherein M 3 =m/2, and the harmonic parameters comprise harmonic frequency Harmonic amplitude Harmonic phase ; The harmonic parameters are ordered according to the magnitude of the harmonic amplitude, a plurality of groups of harmonic parameters corresponding to the harmonic amplitude with larger magnitude are selected to establish an error mathematical model, and the method comprises the following steps: The M 3 groups of harmonic parameters are processed according to the harmonic amplitude Sequencing from large to small, taking the first n 3 groups of harmonic parameters to establish an error mathematical model of a plurality of repetition period errors, and setting up any original displacement value in each repetition period Corresponding error value Determined by the following mathematical model of error: Wherein the original displacement value in the kth repetition period The value range of (2) is [ 0], ; The original displacement value is corrected according to the error value, and a corrected target displacement value is obtained, which comprises the following steps: The corrected target displacement value is determined by the following formula: ; In the formula, Is the corrected target displacement value.
  6. 6. A method for correcting nonlinear periodic errors of a displacement sensor according to claim 3, wherein: before collecting the plurality of error data corresponding to the displacement sensor, the method further includes: Splicing the actual displacement ranges of p repetition periods into continuous actual displacement ranges within the full range, wherein the actual displacement corresponding to the kth repetition period is [ [ , The continuous actual displacement range after p repeated periods are spliced is 0, ]; The fourier transforming the error data to obtain a plurality of groups of harmonic parameters, further includes: Performing Fourier transform on M error data to obtain M 4 groups of harmonic parameters, wherein M 4 =m/2, and the harmonic parameters comprise harmonic frequencies Harmonic amplitude Harmonic phase ; The harmonic parameters are ordered according to the magnitude of the harmonic amplitude, a plurality of groups of harmonic parameters corresponding to the harmonic amplitude with larger magnitude are selected to establish an error mathematical model, and the method further comprises the following steps: the M 4 groups of harmonic parameters are processed according to the harmonic amplitude Sequencing from large to small, taking the first n 4 groups of harmonic parameters to establish an error mathematical model of a continuous actual displacement range after a plurality of repeated periods are spliced, and setting up any original displacement value in the continuous actual displacement range after the repeated periods are spliced Corresponding error value Determined by the following mathematical model of error: Wherein, the The value range of (2) is [ 0], ; The original displacement value is corrected according to the error value, and a corrected target displacement value is obtained, which comprises the following steps: The corrected target displacement value is determined by the following formula: In the formula, Is the corrected target displacement value.
  7. 7. The method for correcting nonlinear periodic errors of a displacement sensor according to claim 4, wherein the method comprises the steps of: before collecting the plurality of error data corresponding to the displacement sensor, the method further includes: Splicing the actual displacement ranges of p repetition periods into continuous actual displacement ranges within the full range, wherein the actual displacement corresponding to the kth repetition period is [ [ , The continuous actual displacement range after p repeated periods are spliced is 0, ]; The fourier transforming the error data to obtain a plurality of groups of harmonic parameters, further includes: respectively summing error data corresponding to the equal interval displacement values of each repetition period to obtain m errors and data; Performing Fourier transform on M error data to obtain M 5 groups of harmonic parameters, wherein M 5 =m/2, and the harmonic parameters comprise harmonic frequencies Harmonic amplitude Harmonic phase ; The harmonic parameters are ordered according to the magnitude of the harmonic amplitude, a plurality of groups of harmonic parameters corresponding to the harmonic amplitude with larger magnitude are selected to establish an error mathematical model, and the method further comprises the following steps: The M 5 groups of harmonic parameters are processed according to the harmonic amplitude Sequencing from large to small, taking the first n 5 groups of harmonic parameters to establish an error mathematical model of a continuous actual displacement range after a plurality of repeated periods are spliced, and setting up any original displacement value in the continuous actual displacement range after the repeated periods are spliced Corresponding error value Determined by the following mathematical model of error: Wherein, the The value range of (2) is [ 0], ]; The original displacement value is corrected according to the error value, and a corrected target displacement value is obtained, which comprises the following steps: The corrected target displacement value is determined by the following formula: In the formula, Is the corrected target displacement value.
  8. 8. The method for correcting nonlinear periodic errors of a displacement sensor according to claim 5, wherein the method comprises the steps of: before collecting the plurality of error data corresponding to the displacement sensor, the method further includes: Splicing the actual displacement ranges of p repetition periods into continuous actual displacement ranges within the full range, wherein the actual displacement corresponding to the kth repetition period is [ [ , The continuous actual displacement range after p repeated periods are spliced is 0, ]; The fourier transforming the error data to obtain a plurality of groups of harmonic parameters, further includes: respectively summing error data corresponding to the equal interval displacement values of each repetition period to obtain m errors and data; Taking p times of average for each error and data to obtain error and average data; Performing Fourier transform on M errors and average data to obtain M 6 groups of harmonic parameters, wherein M 6 =m/2, and the harmonic parameters comprise harmonic frequency Harmonic amplitude Harmonic phase ; The harmonic parameters are ordered according to the magnitude of the harmonic amplitude, a plurality of groups of harmonic parameters corresponding to the harmonic amplitude with larger magnitude are selected to establish an error mathematical model, and the method comprises the following steps: The M 6 groups of harmonic parameters are processed according to the harmonic amplitude Sequencing from large to small, taking the first n 6 groups of harmonic parameters to establish an error mathematical model of a continuous actual displacement range after a plurality of repeated periods are spliced, and setting up any original displacement value in the continuous actual displacement range after the repeated periods are spliced Corresponding error value Determined by the following mathematical model of error: wherein the original displacement value The value range of (2) is [ 0], ; The original displacement value is corrected according to the error value, and a corrected target displacement value is obtained, which comprises the following steps: The corrected target displacement value is determined by the following formula: ; In the formula, Is the corrected target displacement value.
  9. 9. The method of claim 1, wherein the nonlinear periodic error of the displacement sensor over the full range L is a single periodic error, and wherein the method further comprises: sampling m error data according to displacement values at equal intervals in the full range L of the displacement sensor; Performing Fourier transform on M error data to obtain M 7 groups of harmonic parameters, wherein M 7 =m/2, and the harmonic parameters comprise harmonic frequencies Harmonic amplitude Harmonic phase ; The M 7 groups of harmonic parameters are processed according to the harmonic amplitude Sequencing from large to small, taking the first n 7 groups of harmonic parameters to establish an error mathematical model of single period error, wherein the displacement sensor has an arbitrary original displacement value within the full range L Corresponding error value Determined by the following mathematical model of error: In the formula, The value range is [ 0], ; The corrected target displacement value is determined by the following formula: ; In the formula, Is the corrected target displacement value.
  10. 10. A displacement sensor, which is used for a displacement sensor, characterized by comprising the following steps: At least one processor; at least one memory for storing at least one program; when said at least one program is executed by said at least one processor, said at least one processor is caused to implement a displacement sensor nonlinear periodic error correction method as claimed in any one of claims 1-9.

Description

Nonlinear periodic error correction method of displacement sensor and displacement sensor Technical Field The application relates to the technical field of sensors, in particular to a nonlinear periodic error correction method of a displacement sensor and the displacement sensor. Background With the development of electronic circuits and information technologies, sensor technologies have been rapidly developed, wherein displacement sensors include angular displacement sensors and linear displacement sensors, which play an important role in high-end equipment and numerical control machine tools, and the accuracy level of a machined workpiece is determined by the accuracy level. Since the manufacturing process of the displacement sensor has a large influence on the systematic error of the sensor, the systematic error is an error which remains in the sensor and is fixed, and is generally eliminated by improving the manufacturing precision of the sensor, which puts very high demands on processing equipment and processing process, such as high-precision submicron-level PCB processing equipment, high-precision nanometer-level mechanical processing equipment and the like, which can definitely increase the manufacturing cost of the sensor in series, even if the high-precision sensor is manufactured, the sensor cannot be popularized and applied due to cost reasons, and moreover, the nanometer-level and submicron-level mechanical equipment for sensor processing is difficult or even impossible to realize. Under the condition of not improving the requirements on processing equipment and processing technology, the accuracy of the displacement sensor is improved, and an economic and effective method is an error correction technology. In the related art, error correction is one of the effective methods commonly used for eliminating sensor system errors, and when the system errors in the displacement sensor are linear errors or tiny units can be approximated to be linear errors, simple linear correction or least square correction can be adopted to eliminate the system errors, and although the error correction methods are simple, the corrected accuracy is not high, the residual errors are larger, so that the output accuracy of the sensor after error correction is not high. Under the condition that the systematic error in the displacement sensor is a nonlinear periodic error, the error correction method cannot achieve a high-precision error correction effect or even cannot correct the error, and mainly because harmonic components contained in the nonlinear periodic error are more complex, an error mathematical model cannot be accurately built by using simple linear fitting, so that error correction is performed by reconstructing an error curve, and the detection precision of the displacement sensor is affected. In view of the above, there is a need to solve the problems of the related art. Disclosure of Invention The present application aims to solve at least one of the technical problems existing in the related art to a certain extent. Therefore, an objective of the embodiments of the present application is to provide a nonlinear periodic error correction method for a displacement sensor and a displacement sensor. In order to achieve the technical purpose, the technical scheme adopted by the embodiment of the application comprises the following steps: On one hand, the embodiment of the application provides a nonlinear periodic error correction method of a displacement sensor, wherein an error acquisition range is an actual displacement range of the displacement sensor in a plurality of repeated periods, and the method comprises the following steps: Calculating an equidistant displacement value of the actual displacement range according to a theoretical measuring range, and collecting a plurality of error data corresponding to the displacement sensor; performing Fourier transform on the error data to obtain a plurality of groups of harmonic parameters, wherein each group of harmonic parameters comprises harmonic frequency, harmonic amplitude and harmonic phase; Sorting the harmonic parameters according to the magnitude of the harmonic amplitude, and selecting a plurality of groups of harmonic parameters corresponding to the harmonic amplitude with larger magnitude to establish an error mathematical model; Calculating an error value corresponding to any original displacement value based on the error mathematical model; and correcting the original displacement value according to the error value to obtain a corrected target displacement value. In another aspect, an embodiment of the present application provides a displacement sensor, including: At least one processor; at least one memory for storing at least one program; the at least one program, when executed by the at least one processor, causes the at least one processor to implement a method for correcting nonlinear periodic errors of a displacement sensor as described abov