CN114636387A - Circular grating encoder double-reading-head asymmetric installation eccentric error compensation method - Google Patents

Circular grating encoder double-reading-head asymmetric installation eccentric error compensation method Download PDF

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CN114636387A
CN114636387A CN202210240904.6A CN202210240904A CN114636387A CN 114636387 A CN114636387 A CN 114636387A CN 202210240904 A CN202210240904 A CN 202210240904A CN 114636387 A CN114636387 A CN 114636387A
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error
eccentricity
circular grating
installation
reading
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CN114636387B (en
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丁建军
李冠群
李常胜
刘昕东
金雨生
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Xian Jiaotong University
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical techniques
    • G01B11/26Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes
    • G01B11/27Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes for testing the alignment of axes
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D18/00Testing or calibrating apparatus or arrangements provided for in groups G01D1/00 - G01D15/00
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/266Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light by interferometric means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/347Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells using displacement encoding scales
    • G01D5/3473Circular or rotary encoders

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Abstract

The invention discloses a method for compensating an eccentric error of double-reading head asymmetric installation of a circular grating encoder, which is characterized in that a model function is used for performing linear approximation on a parameter to be estimated, the linear approximation is converted into a principle of linear least square problem, a circular grating eccentric simulation model is established to obtain an eccentric parameter, the calculation speed is high, and the result is accurate; by analyzing the angle measurement error compensation principle of the double-reading head under an ideal condition, establishing an average method error compensation ideal model of the double-reading head symmetrical installation, adding installation errors and random errors existing between the reading heads under an actual condition, and further improving the average method error compensation model to obtain an asymmetrical installation error compensation model of the double-reading head; and finally, substituting the eccentric parameters obtained by solving the circular grating eccentric simulation model into the double-reading-head asymmetric installation error compensation model, eliminating the influence of the reading head installation error on the angle measurement precision in actual measurement, and realizing the accurate compensation of the double-reading-head angle measurement eccentric error in the asymmetric installation of the circular grating encoder.

Description

Circular grating encoder double-reading-head asymmetric installation eccentric error compensation method
Technical Field
The invention belongs to the technical field of precision measurement, and particularly relates to a method for compensating an asymmetric installation eccentric error of a double-reading head of a circular grating encoder.
Background
The circular grating encoder has the advantages of high resolution, small volume, convenience in installation, high response speed, simple processing circuit and the like, and is widely applied to the fields of aerospace, intelligent robots, high-grade numerical control machines, high-precision coordinate measuring machines and the like. With the development of science and technology, various instruments tend to be miniaturized and have higher and higher requirements on angle measurement accuracy, and the small-size circular grating perfectly meets the requirements on miniaturization and high accuracy. Meanwhile, the photoelectric pulse signal of the circular grating encoder has strong anti-interference capability, and the running and machining precision of the numerical control machine tool can be well guaranteed. With the continuous development of the technology, the requirement on the measurement accuracy of the circular grating encoder is higher and higher. The research report of international high-end circular grating sensor manufacturing and selling tap enterprises, Heidenhain company of Germany clearly provides that the installation eccentricity error accounts for more than 80% of the angle measurement error, the installation eccentricity error has great influence on the angle measurement precision of a circular grating encoder, and the measurement for calculating the installation eccentricity error parameter and compensating the measurement error caused by the eccentricity error is very important. During installation, the circular grating inevitably generates eccentricity relative to a shaft system, and the installation eccentricity causes an encoder to generate an angle measurement error. Therefore, in order to ensure the system test accuracy, the measurement angle of the circular grating needs to be corrected.
At present, domestic researches on the influence of eccentric errors of circular grating encoder assembly on angle measurement precision are many, and various eccentric error compensation methods are provided, wherein the eccentric errors are eliminated simply and reliably by using double reading heads, and the cost is low. However, the study on the eccentricity error of the double-reading-head circular grating encoder generally considers that the double-reading heads which are radially arranged on the circumference of the grating are in an ideal state, namely the two reading heads are symmetrically arranged with an included angle of 180 degrees. However, in the actual installation process, no matter how the installation accuracy is improved, installation deviation exists between the two reading heads, and for the circular grating encoder with high angle measurement accuracy requirement, the influence of the installation deviation of the double reading heads on the angle measurement accuracy is not negligible.
Disclosure of Invention
The invention aims to solve the technical problem of providing a circular grating encoder double-reading head asymmetric installation eccentricity error compensation method aiming at the defects in the prior art, an error compensation model is constructed based on the principle that sinusoidal signals detected by reading heads at different positions at the same moment in the circular grating angle measurement process have phase difference, the eccentric error compensation principle of double-reading head symmetric installation in an ideal state is combined, a circular grating eccentric parameter solution model based on an L-M algorithm obtains circular grating installation eccentricity parameters in an nonideal state, and the circular grating encoder angle measurement eccentricity error compensation model is established based on the eccentric error compensation model, so that accurate compensation of the circular grating encoder double-reading head angle measurement eccentricity error is realized.
The invention adopts the following technical scheme:
a method for compensating the eccentric error of the asymmetric installation of the double reading heads of a circular grating encoder comprises the following steps:
s1, solving the eccentricity and the eccentricity direction of the circular grating based on an L-M algorithm according to the synthesis of sinusoidal signals with different phases in the circumferential direction of the circular grating, and establishing a circular grating eccentricity parameter simulation model;
s2, establishing a mean error compensation ideal model with symmetrically installed double reading heads;
s3, adding a reading head installation error and a random error into the ideal error compensation model of the averaging method established in the step S2, and establishing an asymmetric double-reading-head installation error compensation model;
s4, obtaining the eccentricity of the circular grating through microscope measurement, substituting the eccentricity as an initial value into the circular grating eccentricity parameter simulation model established in the step S1, and obtaining the real eccentricity through iteration;
and S5, substituting the real eccentricity obtained in the step S4 into the double-reading-head asymmetric installation error compensation model established in the step S3, and realizing accurate compensation of the angle measurement error caused by the installation eccentricity of the circular grating.
Specifically, in step S1, the sinusoidal signal phase difference Δ ψ detected by two reading heads at different positions in the circumferential direction at the same time12Comprises the following steps:
Figure BDA0003541570260000021
where d is the grating pitch, 360 represents the number of angles in one period of the electrical fringe signal,
Figure BDA0003541570260000022
is the mounting angle between the two reading heads, and e is the eccentricity.
Further, the eccentricity e is specifically as follows:
Figure BDA0003541570260000031
where Δ ψ is the total phase difference read by the two read heads.
Specifically, in step S2, the ideal model for error compensation by the averaging method specifically includes:
Figure BDA0003541570260000032
wherein the content of the first and second substances,
Figure BDA0003541570260000033
for the error compensation result of the averaging method, theta is the theoretical rotation angle without error, tau1Is the mounting position of the first reading head, τ2Is the mounting position of the second reading head, psi (theta)1) Angle measurement error, delta (theta), caused by inconsistencies within the first readhead1) For random errors due to other uncertainties of the first readhead, ψ (θ)2) Angle error, delta (theta), caused by inconsistencies within the second read head2) Due to other uncertainties of the second read headRandom error of start.
Specifically, in step S3, the asymmetric mounting error compensation model with dual reading heads specifically includes:
Figure BDA0003541570260000034
wherein the content of the first and second substances,
Figure BDA0003541570260000035
representing the measured value of the angle of rotation compensated by the new method,
Figure BDA0003541570260000036
for the compensated angle measurement error, e is the eccentricity, R is the code disc radius, omega is the eccentricity angle, theta1,θ2The rotation angle measured by the first reading head and the first reading head during the rotation process.
Further, the angle measurement errors of the first reading head and the second reading head are respectively:
Figure BDA0003541570260000037
Figure BDA0003541570260000038
wherein, theta is the theoretical rotation angle without error.
Specifically, in step S4, the solution of the eccentricity and the eccentricity direction of the circular grating based on the L-M algorithm specifically includes:
setting an initial value of an eccentricity e, an eccentricity angle omega and a code disc radius R; calculating a Jacobian matrix J and a function value; calculating an error, and if the error is smaller than a set threshold value, terminating; otherwise, continuing; calculating the value of the Hessian matrix: h ═ J' × J; calculating a search step length d; calculating new parameters and function values; calculating a new error; if the error ratio is reduced than the last time, updating the parameters and reducing the damping coefficient mu, if the error is increased, increasing the damping coefficient, not updating the parameters, returning to calculate the Jacobian matrix J and the function value, and continuing iteration.
Further, xiSearch step d of pointsiComprises the following steps:
Figure BDA0003541570260000041
wherein, JiIs a Jacobian matrix, muiFor damping coefficient, I is an identity matrix, F (x)i) Error theta for measuring angle of first reading head and second reading head21The functional expression of the formula.
Specifically, in step S5, the compensation model for the angle measurement error in the asymmetric installation of the dual-reading head specifically includes:
and the eccentricity direction calculated by the circular grating eccentricity parameter solving model are used as input variables, and the measured angle eccentricity error compensation value is used as an output variable, so that the accurate compensation of the measured angle error of the circular grating encoder caused by the installation eccentricity and the reading head installation deviation is realized.
In a second aspect, an embodiment of the present invention provides a system for compensating an eccentric error of a double-reading head asymmetric installation of a circular grating encoder, including:
the simulation module is used for solving the eccentricity and the eccentricity direction of the circular grating based on an L-M algorithm according to the synthesis of sinusoidal signals with different phases in the circumferential direction of the circular grating, and establishing a circular grating eccentricity parameter simulation model;
the ideal module is used for establishing an error compensation ideal model of a mean value method with symmetrically installed double reading heads;
the real module is used for adding a reading head installation error and a random error into the ideal model of the error compensation of the mean value method established by the ideal module and establishing a double-reading head asymmetric installation error compensation model;
the iteration module is used for obtaining the eccentricity of the circular grating through microscope measurement, substituting the eccentricity as an initial value into the circular grating eccentricity parameter simulation model established by the simulation module, and obtaining the real eccentricity through iteration;
and the compensation module substitutes the real eccentricity obtained by the iteration module into the double-reading-head asymmetric installation error compensation model established by the reality module to realize accurate compensation of the angle measurement error caused by the installation eccentricity of the circular grating.
Compared with the prior art, the invention has at least the following beneficial effects:
the invention relates to a method for compensating an eccentric error of double-reading head asymmetric installation of a circular grating encoder, which comprises the steps of establishing a circular grating eccentric simulation model, establishing an average method error compensation ideal model of the double-reading head symmetric installation, establishing a double-reading head asymmetric installation error compensation model and establishing an eccentric parameter simulation model based on an L-M algorithm, wherein the adjustment band of a circular grating is 30 microns, so that the difficulty of measuring an eccentric distance by using a microscope is high and inaccurate, the accurate eccentric parameter can be obtained by establishing the circular grating eccentric simulation model, the key of the L-M algorithm is to use a model function to perform linear approximation on a parameter to be estimated in the field of the L-M algorithm, a derivative term above the second order is omitted, the L-M algorithm is converted into a linear least square problem, and the convergence speed is high; under an ideal condition, no installation error exists between the two reading heads, an average method error compensation ideal model of the double-reading-head symmetrical installation is established on the basis of the ideal condition, and the installation error between the reading heads is not considered under an actual condition, so that the average method error compensation model needs to be improved, and the installation error and the random error between the reading heads are added to obtain an asymmetric installation error compensation model of the double-reading-head; and substituting the eccentricity calculated by the circular grating eccentricity simulation model as an initial value into the double-reading-head asymmetric installation error compensation model to realize accurate compensation of the angle measurement error caused by the circular grating installation eccentricity.
Further, as can be seen from the principle of circular grating angle measurement, monochromatic light emitted by the laser passes through the grid lines of the grating disk to generate interference fringes, and the photoelectric receiver can generate a sinusoidal signal in the oscilloscope after receiving light and dark fringe light signals generated by interference. When the circular grating has eccentricity, sinusoidal signals detected by reading heads at different positions in the circumferential direction at the same moment have phase difference. By utilizing the characteristic, the eccentric direction and the eccentric distance of the circular grating can be detected according to the synthesis of sinusoidal signals with different phases.
Furthermore, the eccentricity of the circular grating can be calculated by using the total phase difference delta psi read by the 2 reading heads when the circular grating rotates 180 degrees anticlockwise from the minimum value point to the maximum value point, namely, a circular grating eccentricity simulation model is established on the basis of the data of the two reading heads so as to solve the eccentricity, so that the measurement error caused by the method of measuring the eccentricity by using a microscope is avoided, and the result is more accurate. .
Furthermore, under the ideal condition, namely under the condition that no installation error exists between the two reading heads, the ideal model of the mean error compensation of the symmetrical installation of the double reading heads is established, the theoretical analysis of the angle measurement error of the double reading heads can be simply and clearly carried out, and the foundation is laid for establishing the error compensation model under the actual condition.
Furthermore, in actual conditions, a certain installation error exists between the two reading heads more or less, so that the ideal error compensation model for the symmetrical installation of the double reading heads by the averaging method cannot completely compensate the angle measurement error of the double reading heads, the installation error of the two reading heads can be considered by establishing the asymmetrical installation error compensation model of the double reading heads, the angle measurement error is compensated better, and the measurement precision is improved on the basis of ensuring the accuracy of the measurement result.
Furthermore, installation error solving formulas of the first reading head and the second reading head are respectively given, so that the two formulas are connected, namely, the data of the two reading heads are connected together, and a foundation is laid for solving the eccentricity through an eccentric simulation model.
Furthermore, the key of the L-M algorithm is that a model function is used for performing linear approximation on the parameter to be estimated in the field of the parameter to be estimated, derivative terms above the second order are omitted, and therefore the linear least square problem is converted, and the convergence speed is high. Therefore, the eccentricity and the eccentricity direction of the circular grating are solved based on the L-M algorithm, so that the calculation speed is high, and the calculation result is accurate.
Further, the Gauss-Newton algorithm requires that the Jacobian matrix must be column full rank, and therefore for xiSearch step d of pointsiThe improvement is carried out to obtain an L-M algorithmThe method breaks through the limitation that the Jacobian matrix must be column full rank, and improves the flexibility of the algorithm.
Furthermore, in practical situations, due to the influence of factors such as machining and manufacturing errors of parts, irregular installation and the like, the double-reading head is difficult to ensure complete radial installation in the installation process, so that installation errors between the two reading heads are inevitable, the installation errors of the double-reading head are taken into consideration by establishing an asymmetrical double-reading head installation angle measurement error compensation model, and the influence of the double-reading head installation errors on the circular grating angle measurement precision is further effectively eliminated.
In summary, the invention makes linear approximation to the parameter to be estimated in the field by using the model function, omits the derivative term above the second order, and thus converts the linear least square problem into the principle to establish the circular grating eccentric simulation model and further solve to obtain the accurate eccentric parameter, so that the calculation speed is high, and the calculation result is also accurate; by analyzing the angle measurement error compensation principle of the double-reading head under an ideal condition, establishing an average method error compensation ideal model of the double-reading head symmetrical installation, adding installation errors and random errors existing between the reading heads under an actual condition on the basis of the model, and further improving the average method error compensation model to obtain a double-reading head asymmetric installation error compensation model; and finally, substituting the eccentric parameters obtained by solving the circular grating eccentric simulation model into the double-reading-head asymmetric installation error compensation model, eliminating the influence of the reading head installation error on the angle measurement precision in actual measurement, and finally realizing the accurate compensation of the double-reading-head angle measurement eccentric error in the asymmetric installation of the circular grating encoder.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
FIG. 1 is a schematic view of eccentric installation of a circular grating encoder;
FIG. 2 is a schematic diagram of the eccentricity error of a circular grating encoder;
FIG. 3 is a schematic diagram of eccentric error measurement by a dual-reading head;
FIG. 4 is a graph of measurement error introduced by eccentricity;
FIG. 5 is a diagram of a measurement system;
FIG. 6 is a flow chart of eccentricity parameter solving based on L-M algorithm;
FIG. 7 is a graph of angular error before and after compensation of a circular grating encoder.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be understood that the terms "comprises" and/or "comprising" indicate the presence of the stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
It is also to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
It should be further understood that the term "and/or" as used in this specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and including such combinations, e.g., a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.
It should be understood that although the terms first, second, third, etc. may be used to describe preset ranges, etc. in embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, the first preset range may also be referred to as a second preset range, and similarly, the second preset range may also be referred to as the first preset range, without departing from the scope of the embodiments of the present invention.
The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination" or "in response to a detection", depending on the context. Similarly, the phrases "if determined" or "if detected (a stated condition or event)" may be interpreted as "when determined" or "in response to a determination" or "when detected (a stated condition or event)" or "in response to a detection (a stated condition or event)", depending on the context.
Various structural schematics according to the disclosed embodiments of the invention are shown in the drawings. The figures are not drawn to scale, wherein certain details are exaggerated and possibly omitted for clarity of presentation. The shapes of various regions, layers and their relative sizes and positional relationships shown in the drawings are merely exemplary, and deviations may occur in practice due to manufacturing tolerances or technical limitations, and a person skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions, according to actual needs.
The invention provides a method for compensating eccentric error of double-reading head asymmetric installation of a circular grating encoder, which is characterized in that an error compensation model is constructed by utilizing the principle that sinusoidal signals detected by reading heads at different positions at the same moment in the angle measurement process of the circular grating and combining the eccentric error compensation principle of the double-reading head symmetric installation in an ideal state, the eccentric parameter of the circular grating is solved based on an L-M algorithm to obtain the eccentric parameter of the circular grating installation in the non-ideal state, and the angle measurement eccentric error compensation model of the circular grating encoder is established on the basis of the eccentric parameter of the circular grating, so that the accurate compensation of the eccentric error of the double-reading head asymmetric installation state of the circular grating encoder is realized.
Referring to fig. 1, the method for compensating the eccentric error of the asymmetric installation of the dual-reading head of the circular grating encoder of the present invention includes the following steps:
s1, based on the principle of circular grating angle measurement error, when the circular grating has eccentricity, the sinusoidal signals detected by the reading heads at different positions in the circumferential direction at the same moment have phase difference, and a circular grating eccentricity parameter simulation model is established according to the synthesis of the sinusoidal signals with different phase differences;
based on the principle of angle measurement error of the circular grating, monochromatic light emitted by a laser generates interference fringes through grid lines of a grating disc, and a photoelectric receiver generates a sinusoidal signal in an oscilloscope after receiving the interference fringe light; when the circular grating is eccentric, sinusoidal signals detected by the reading heads at different positions in the circumferential direction at the same moment have phase differences; by utilizing the characteristic, the eccentric direction and the eccentric distance of the circular grating are detected according to the synthesis of sinusoidal signals with different phases, and then a circular grating eccentric detection model is established.
2 photoelectric reading heads are used for collecting fringe signals, and the first reading head and the second reading head are respectively arranged at A1、A2The positions are radially arranged by taking the rotation center OD as a center. Due to the fact that the geometric center of the circular grating is eccentric relative to the rotating shaft, the grating number of the first reading head and the grating number of the second reading head which pass through the same time are different, namely the lengths of the 2 photoelectric reading heads which pass through the optical circumference in the same time are different. Therefore, the sinusoidal signals detected by the first reading head and the second reading head have differences in frequency and phase.
When the rotating shaft rotates along a fixed direction, the difference of the lengths of the first reading head and the second reading head passing through the optical circumference at the same time is
Figure BDA0003541570260000091
From the theory of small angle approximation, it can be known that
Figure BDA0003541570260000092
And O isME⊥A1A2According to the geometric similarity relationship shown in FIG. 2, the length difference
Figure BDA0003541570260000093
Expressed as:
Figure BDA0003541570260000094
wherein the content of the first and second substances,
Figure BDA0003541570260000095
is eccentric direction and A1A2The included angle between the directions.
Difference in length
Figure BDA0003541570260000096
The number of angles corresponding to the period of the electrical fringe signals is the phase difference between the sinusoidal signals detected by the 2 reading heads, and the relative phase difference between the signals received by the first reading head and the second reading head is expressed as:
Figure BDA0003541570260000097
where d is the grating pitch and 360 represents the number of angles in one period of the electrical fringe signal. The phase difference between the first reading head and the second reading head changes along with the change of the rotation angle of the rotating shaft.
In the process of one rotation of the measured shaft, the difference of the eccentric distance between the first reading head and the second reading head reaches the extreme point 2 times, as shown in fig. 2, corresponding to the eccentric direction and a1A2The direction is orthogonal for 2 points read by the receiver 2. Circular grating from minimum point PminRotated 180 DEG counterclockwise to reach a maximum point PmaxThe total phase difference read by the 2 reading heads is delta psi; and further converting the arrangement formula to obtain a calculation formula of the eccentricity e.
Figure BDA0003541570260000101
When the second reading head reads an extreme point, the recording is started, and after the circular grating rotates 90 degrees, the eccentric direction will be equal to A1A2The directions are consistent. Therefore, after capturing the phase extremum point in the oscilloscope,the eccentric direction of the circular grating can be determined according to the orthogonal relation.
S2, correcting and compensating the angle measurement error caused by the eccentric installation of the circular grating by adopting a double-reading-head symmetrical installation method, effectively compensating and correcting the angle measurement error, and establishing an average error compensation ideal model of the double-reading-head symmetrical installation based on the principle;
the method for correcting and compensating the angle measurement error caused by the installation eccentricity of the circular grating by adopting the double-reading head method can effectively compensate and correct the angle measurement error, and under the ideal installation condition, the establishment of the double-reading head symmetrical error compensation model can effectively eliminate the installation eccentricity of the circular grating and the radial motion deviation of a shaft system.
For a double-reading head circular grating angle measurement system, the method of averaging is a conventional error correction method. The ideal error compensation model by the averaging method is as follows:
Figure BDA0003541570260000102
the average method is simple to calculate, but has higher requirement on the installation accuracy of the two reading heads; when the reading head has no installation error, wherein1=0°,τ2=180°。
At this time, the above formula may be deformed as:
Figure BDA0003541570260000103
the angle measurement error caused by the installation eccentricity of the circular grating and the radial runout of the shafting is eliminated. However, when there is a mounting error in the reading head, the averaging method cannot completely eliminate the influence of the two errors. Through the analysis of the error source and the influence mechanism in the circular grating angle measuring system, the application of the double-reading-head averaging method in the environment with larger installation errors of the reading head has certain limitation.
S3, adding a reading head installation error and a random error into the ideal error compensation model of the averaging method established in the step S2, and establishing an asymmetric double-reading-head installation error compensation model;
in the actual installation process, the double reading heads cannot reach an ideal state, namely, installation deviation exists between the two reading heads, so that the adverse effect of installation eccentricity on angle measurement precision cannot be effectively eliminated.
The method for correcting the eccentric error of the circular grating with the double reading heads installed in a non-diameter-aligning manner can reduce the adverse effect of the diameter-aligning installation error on a measurement result; on the other hand, the limitation that the reading head must be installed in a diameter direction is broken through, and the degree of freedom of the instrument and equipment in structural design is improved.
Under precision measurement conditions, the magnitudes of random and systematic errors are often close; after the system error is corrected correctly, the amplitude of the random error may exceed the amplitude of the system error, and the random error component is added into the double-reading-head symmetrical installation error compensation model, so that the influence of the random error on the compensation result can be effectively eliminated.
Please refer to fig. 3, O1Is the rotation center of a shaft system, O is the geometric center of a circular grating disc, and C, D is the installation positions of two reading heads; OO1The eccentricity of the circular grating disk is denoted by e; less than O1OD is the eccentric angle of the circular grating disc and is represented by omega; arc angle O1OC is represented by eta; for convenience of presentation, the shaft and circular grating disk are fixed in FIG. 3, and the reading head is wound around the rotation center O1Rotating counterclockwise by an angle theta from point C, D to points A and B; theta.theta.1,θ2The rotation angles measured by the two reading heads in the rotation process; mounting angle CO of two reading heads1For D
Figure BDA0003541570260000111
Representing; when the double reading head is strictly installed in a diameter-alignment way, namely, no reading head installation position error exists,
Figure BDA0003541570260000112
the angle measurement error of the first reading head can be obtained by the fact that the triangle outer angle is equal to the sum of two non-adjacent inner angles:
Figure BDA0003541570260000113
and obtaining the angle measurement error of the second reading head in the same way:
Figure BDA0003541570260000114
from FIG. 3, it can be seen that
sinη[sinα+cos(ω+γ+φ)sin(ω-θ1)]+cosηsin(ω+γ+φ)sin(ω-θ1)=0
Let m be sin α + cos (ω + γ + φ) sin (ω - θ)1),n=sin(ω+γ+φ)·sin(ω-θ1) And then:
m·sinη+n·cosη=0
obtaining the following formula according to the auxiliary angle:
Figure BDA0003541570260000121
Figure BDA0003541570260000122
the relation between the measured values of the two reading heads and the eccentricity parameter can be obtained by the following formula:
Figure BDA0003541570260000123
wherein, only the reading of two reading heads and the installation eccentricity parameter of the circular grating are included. Two of the readheads read θ1,θ2The acquisition may be performed by a data acquisition system. Rotating the shaft system for one circle to obtain a series of theta1,θ2The circular grating installation eccentric parameters can be fitted by using a least square method, so that the calibration of the circular grating installation eccentric parameters is realized
The asymmetric installation error compensation model of the double-reading head is obtained through the analysis as follows:
Figure BDA0003541570260000124
wherein, the first and the second end of the pipe are connected with each other,
Figure BDA0003541570260000125
representing the measured value of the rotation angle compensated by the new method, and the compensated angle measurement error can be expressed as
Figure BDA0003541570260000126
In practical application, the measured shaft drives the circular grating to rotate for one circle to obtain the installation eccentricity parameter of the circular grating and the installation position error parameter of the two reading heads, and then the readings theta of the two reading heads are used1,θ2And substituting to obtain a compensated angle measurement result, wherein the adverse effects of circular grating installation eccentricity and reading head diameter installation error are eliminated.
S4, obtaining the eccentricity of the circular grating through microscope measurement, substituting the eccentricity as an initial value into the circular grating eccentricity parameter simulation model established in the step S1, and obtaining the real eccentricity through iteration;
the circular grating eccentric parameter solving model specifically comprises the following steps:
based on a Gauss-Newton algorithm, the search step length is improved, the limitation that a Jacobian matrix in the Gauss-Newton algorithm must be column full rank is eliminated, and then a circular grating eccentricity parameter solving model based on an L-M algorithm is obtained.
The study used the L-M algorithm to solve for the eccentricity parameters of the circular grating.
Will be provided with
Figure BDA0003541570260000131
Is denoted as F (x)i) 0, wherein xi=[ei,Ri,ωi]. The eccentricity error parameter identification problem is then expressed as:
Figure BDA0003541570260000132
the gradient and the Hessian matrix of the objective function f are respectively:
Figure BDA0003541570260000133
Figure BDA0003541570260000134
wherein the content of the first and second substances,
Figure BDA0003541570260000135
is a matrix of the Jacobian ratio,
Figure BDA0003541570260000136
using Newton iteration method to obtain:
Figure BDA0003541570260000137
ignoring s (x) therein, we get:
xi+1=xi+di
wherein the content of the first and second substances,
Figure BDA0003541570260000138
is f (x) at xiThe search step size of the point. The above equation is the Gauss-Newton algorithm, but this algorithm requires that the jacobian matrix must be column full rank.
For search step length dkThe improvement is as follows:
Figure BDA0003541570260000139
wherein I is a unit matrix, muiIs the damping coefficient. The equation obtained at this time is the L-M algorithm.
Referring to fig. 6, the specific steps of solving the eccentricity parameter by the L-M algorithm are as follows:
1) setting an initial value of an eccentricity e, an eccentricity angle omega and a code disc radius R;
2) calculating a Jacobian matrix J and a function value;
3) and calculating an error, and if the error is less than a set threshold value, terminating. Otherwise, continuing;
4) calculating the value of the Hessian matrix, wherein H is J' multiplied by J;
5) calculating a search step length d;
6) calculating new parameters and function values;
7) calculating a new error;
8) if the error is smaller than the last time, updating the parameters and reducing the damping coefficient mu, if the error is larger, increasing the damping coefficient, not updating the parameters, and returning to the step 2) to continue iteration.
The L-M algorithm can be implemented using the nlinfit function in MATLAB software. The solution of the eccentricity error compensation model needs to set initial values of 3 parameters, namely eccentricity e, eccentricity angle omega and code disc radius R. The initial values of the eccentricity e and the eccentricity angle omega are set by random numbers, and the radius of the code disc is set according to the size of the actually selected circular grating.
And S5, substituting the real eccentricity obtained in the step S4 into the double-reading-head asymmetric installation error compensation model established in the step S3, and realizing accurate compensation of the angle measurement error caused by the installation eccentricity of the circular grating.
The double-reading head asymmetric installation angle measurement error compensation model specifically comprises the following steps:
and the eccentricity direction calculated by the circular grating eccentricity parameter solving model are used as input variables, and the measured angle eccentricity error compensation value is used as an output variable, so that the accurate compensation of the measured angle error of the circular grating encoder caused by the installation eccentricity and the reading head installation deviation is realized.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 5, the constant-speed driving device drives the platform to rotate through the coupler, the circular grating is mounted on the rotating platform and rotates with the platform, and the first reading head and the second reading head are mounted above the grid line of the circular grating to measure the rotating angle of the circular grating.
Referring to fig. 4, a curve shows the influence of the circular grating installation eccentricity on the angle measurement accuracy when a single reading head measures an angle, and the influence of the circular grating installation eccentricity on the angle measurement accuracy can be seen from the graph to be very obvious, so that the angle measurement error caused by the eccentricity is corrected by adopting a measurement method of symmetrically installing double reading heads.
Referring to fig. 7, two curves are respectively measurement errors introduced by the installation eccentricity of the circular grating before and after compensation, and it can be seen that after the compensation is performed by using the double-reading head asymmetric installation error compensation model, the angle measurement accuracy of the circular grating system is significantly improved.
And (3) comprehensively analyzing the model result, setting the eccentricity e to be 10 mu m, setting the radius R of the circular grating disc to be 26mm, setting the eccentric angle to be 60 degrees and setting the installation error of the two reading heads to be 2 degrees, substituting the preset parameters into the model, fitting the simulation data by using a least square method to obtain the eccentricity e to be 10.070 mu m, setting the eccentric angle to be 59.465867 degrees and setting the installation error of the two reading heads to be 2.000030 degrees, basically conforming to the input parameters, and proving the accuracy of the eccentric parameter fitting algorithm. Therefore, the measurement can be carried out on the circular grating carried on the air floatation rotary table. Two reading heads A and B are arranged in the radial direction, and a circular grating encoder of RCDM20-108 series of Ranisha company is used, and the diameter of the circular grating is 108 mm. And rotating the circular grating, observing the value of the reading head A, recording the values of the reading heads A and B at intervals of 15 degrees until 24 groups of data are obtained after one rotation, and solving the eccentric parameters of the circular grating by using an L-M algorithm according to experimental data. Solving needs to set initial values of 3 parameters of eccentricity ratio a, eccentricity angle w and included angle alpha of the two reading heads, because the two reading heads are installed in an approximate diameter-matching mode, the initial value of the included angle alpha of the two reading heads is set to be 180 degrees. The initial values of the eccentricity a and the eccentricity w are set by random numbers, and finally, the eccentricity parameters of the circular grating are solved by 69 times of iteration, wherein the eccentricity e is 1.8 mu m, and the included angle alpha of the two reading heads is 179.250 degrees. Substituting the solved parameters into the following formula
Figure BDA0003541570260000151
Through model analysis, the eccentricity error is generated due to the fact that the geometric center of the circular grating and the rotation center of the measured shaft are not coincident in the installation process, and is a regular system error, and the error value of the eccentricity error changes periodically along with the rotation angle of the rotating shaft. The larger the eccentricity is, the larger the angle measurement error is; under the same eccentric quantity, the larger the diameter of the grating ring is, the smaller the angle measurement error is; the angle measurement eccentricity error is periodically changed along with the rotation of the grating ring, the axis system rotates for a circle, and the error is changed for a period and is expressed as a first harmonic in an error frequency spectrum. The double-reading-head symmetric error compensation model can effectively eliminate the installation eccentricity of the circular grating and the radial motion deviation of a shaft system, so that the circular grating installation eccentricity compensation model is theoretically constructed. In consideration of the tiny installation deviation between the two reading heads in the actual installation process, the adverse effect of the diameter-aligning installation error on the measurement result can be reduced on the one hand by adopting a circular grating eccentric error correction method for installing the double reading heads in a non-diameter-aligning way; on the other hand, the limitation that the reading head must be installed in a diameter direction is broken through, and the degree of freedom of the instrument and equipment in structural design is improved. And based on a circular grating eccentricity parameter solving model, the eccentricity and the eccentricity direction calculated by the model are used as input variables, and the measured angle eccentricity error compensation value is used as an output variable, so that the accurate compensation of the measured angle error of the circular grating encoder caused by the installation eccentricity and the reading head installation deviation is realized. According to the experimental result, the average error of the angle measurement of the circular grating encoder before compensation is 6.81 ', the average error of the angle measurement of the circular grating encoder after compensation is 2.28 ', the angle measurement error caused by eccentricity can be effectively compensated by adopting a circular grating eccentricity error correction method of installing double reading heads in a non-diameter-aligning mode, and the angle measurement precision of the encoder is improved by 4.53 '. The pitch error peak-to-valley value before compensation was 10.52 ", the pitch error peak-to-valley value after compensation was 2.83", and the precision was improved by 7.69 ". In conclusion, the circular grating eccentricity error correction model with the non-diameter-alignment-mounted double-reading head can effectively eliminate the influence of the mounting eccentricity of the code wheel on the accuracy of circular grating angle measurement, and has important significance for improving the accuracy of circular grating encoder angle measurement.
In summary, according to the method for compensating the eccentric error of the double-reading head asymmetric installation of the circular grating encoder, the double-reading head symmetric error compensation model can effectively eliminate the installation eccentricity of the circular grating and the radial motion deviation of the shafting, so that the circular grating installation eccentric error compensation model is theoretically constructed. In consideration of the tiny installation deviation between the two reading heads in the actual installation process, the method for correcting the eccentric error of the circular grating with the non-diameter-aligning double reading heads can reduce the adverse effect of the diameter-aligning installation error on the measurement result on one hand; on the other hand, the limitation that the reading head must be installed in a diameter direction is broken through, and the degree of freedom of the instrument and equipment in structural design is improved. And based on a circular grating eccentricity parameter solving model, the eccentricity and the eccentricity direction calculated by the model are used as input variables, and the measured angle eccentricity error compensation value is used as an output variable, so that the accurate compensation of the measured angle error of the circular grating encoder caused by the installation eccentricity and the reading head installation deviation is realized. According to the experimental result, the average error of the angle measurement of the circular grating encoder before compensation is 6.81 ', the average error of the angle measurement of the circular grating encoder after compensation is 2.28 ', the angle measurement error caused by eccentricity can be effectively compensated by adopting a circular grating eccentricity error correction method of installing double reading heads in a non-diameter-aligning mode, and the angle measurement precision of the encoder is improved by 4.53 '. The pitch error peak-to-valley value before compensation was 10.52 ", the pitch error peak-to-valley value after compensation was 2.83", and the precision was improved by 7.69 ". In conclusion, the circular grating eccentricity error correction model with the non-radial installation of the double-reading head can effectively eliminate the influence of the installation eccentricity of the code disc on the accuracy of the circular grating angle measurement, and has important significance for improving the angle measurement accuracy of the circular grating encoder.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.

Claims (9)

1. A method for compensating an eccentric error of double-reading head asymmetric installation of a circular grating encoder is characterized by comprising the following steps:
s1, solving the eccentricity and eccentricity direction of the circular grating based on an L-M algorithm according to the synthesis of sinusoidal signals with different phases in the circumferential direction of the circular grating, and establishing a circular grating eccentricity parameter simulation model;
s2, establishing an error compensation ideal model of the averaging method with symmetrically installed double reading heads;
s3, adding a reading head installation error and a random error into the ideal error compensation model of the averaging method established in the step S2, and establishing a double-reading-head asymmetric installation error compensation model;
s4, obtaining the eccentricity of the circular grating through microscope measurement, substituting the eccentricity as an initial value into the circular grating eccentricity parameter simulation model established in the step S1, and obtaining the real eccentricity through iteration;
and S5, substituting the real eccentricity obtained in the step S4 into the double-reading-head asymmetric installation error compensation model established in the step S3, and realizing accurate compensation of the angle measurement error caused by the installation eccentricity of the circular grating.
2. The method for compensating the eccentric error of the asymmetric installation of the dual reading heads of the circular grating encoder as claimed in claim 1, wherein in step S1, the phase difference Δ ψ of the sinusoidal signals detected by the two reading heads at the same time at different positions in the circumferential direction12Comprises the following steps:
Figure FDA0003541570250000011
where d is the grating pitch, 360 represents the number of angles in one period of the electrical fringe signal,
Figure FDA0003541570250000012
is the mounting angle between the two reading heads, and e is the eccentricity.
3. The method for compensating the asymmetric installation eccentricity error of the double-reading head of the circular grating encoder as claimed in claim 2, wherein the eccentricity e is specifically as follows:
Figure FDA0003541570250000013
where Δ ψ is the total phase difference read by the two read heads.
4. The method for compensating for the eccentric error of the asymmetric installation of the dual-reading head of the circular grating encoder as claimed in claim 1, wherein in the step S2, the ideal model for compensating the error of the averaging method specifically comprises:
Figure FDA0003541570250000014
wherein, the first and the second end of the pipe are connected with each other,
Figure FDA0003541570250000015
for the error compensation result of the averaging method, theta is the theoretical rotation angle without error, tau1Is the mounting position of the first reading head, τ2Is the mounting position of the second reading head, psi (theta)1) Angle measurement error, delta (theta), caused by inconsistencies within the first readhead1) For random errors due to other uncertainties of the first readhead, ψ (θ)2) Is a secondAngular error, delta (theta), caused by inconsistencies within the readhead2) Random errors due to other uncertainties of the second read head.
5. The method for compensating the asymmetric installation eccentricity error of the dual-reading head of the circular grating encoder as claimed in claim 1, wherein in step S3, the asymmetric installation error compensation model of the dual-reading head specifically comprises:
Figure FDA0003541570250000021
wherein the content of the first and second substances,
Figure FDA0003541570250000022
representing the measured value of the angle of rotation compensated by the new method,
Figure FDA0003541570250000023
in order to measure the angle error after compensation, e is the eccentricity, R is the radius of the code disc, omega is the eccentricity angle, and theta is1,θ2The rotation angle measured by the first reading head and the first reading head during the rotation process.
6. The method for compensating the asymmetric installation eccentricity error of the double reading heads of the circular grating encoder as claimed in claim 5, wherein the angle measurement errors of the first reading head and the second reading head are respectively as follows:
Figure FDA0003541570250000024
Figure FDA0003541570250000025
wherein, theta is the theoretical rotation angle without error.
7. The method for compensating the eccentric error of the asymmetric installation of the dual-reading head of the circular grating encoder as claimed in claim 1, wherein the step S4 of solving the eccentricity and the eccentricity direction of the circular grating based on the L-M algorithm specifically comprises:
setting an initial value of an eccentricity e, an eccentricity angle omega and a code disc radius R; calculating a Jacobian matrix J and a function value; calculating an error, and if the error is smaller than a set threshold value, terminating; otherwise, continuing; calculating the value of the Hessian matrix: h ═ J' × J; calculating a search step length d; calculating new parameters and function values; calculating a new error; if the error ratio is reduced than the last time, updating the parameters and reducing the damping coefficient mu, if the error is increased, increasing the damping coefficient, not updating the parameters, returning to calculate the Jacobian matrix J and the function value, and continuing iteration.
8. The method of claim 7, wherein x is xiSearch step d of pointsiComprises the following steps:
Figure FDA0003541570250000031
wherein, JiIs a Jacobian matrix, muiIs damping coefficient, I is identity matrix, F (x)i) Error theta for measuring angle of first reading head and second reading head21The functional expression of the expression.
9. The method for compensating for the asymmetric installation eccentricity error of the dual-reading head of the circular grating encoder as claimed in claim 1, wherein in step S5, the asymmetric installation angle measurement error compensation model of the dual-reading head specifically comprises:
and the eccentricity direction obtained by calculation of the circular grating eccentricity parameter solving model are used as input variables, and the angle measurement eccentricity error compensation value is used as an output variable, so that the accurate compensation of the angle measurement error caused by the installation eccentricity and the reading head installation deviation of the circular grating encoder is realized.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2466271A1 (en) * 2010-12-20 2012-06-20 Mitutoyo Corporation Method, computer program product and rotary encoder for estimation of eccentric value
CN102519723A (en) * 2012-01-09 2012-06-27 唐进元 Measurement and control system for dynamic transmission error of gear
CN102680016A (en) * 2012-05-14 2012-09-19 北京理工大学 Error compensating method of photoelectric encoder
CN104460320A (en) * 2014-12-05 2015-03-25 西安理工大学 Circle shear overlap amount controller parameter optimizing method based on brainstorming
CN104614982A (en) * 2014-12-05 2015-05-13 西安理工大学 Method for adjusting overlap parameters of cycle shear based on multi-target brainstorming
CN107063091A (en) * 2017-04-11 2017-08-18 合肥工业大学 For big L/D ratio pipe fitting endoporus measuring multiple parameters device and method
CN112902877A (en) * 2021-01-15 2021-06-04 河南科技大学 Non-radial installation double-reading head circular grating angle measurement error correction method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2466271A1 (en) * 2010-12-20 2012-06-20 Mitutoyo Corporation Method, computer program product and rotary encoder for estimation of eccentric value
CN102519723A (en) * 2012-01-09 2012-06-27 唐进元 Measurement and control system for dynamic transmission error of gear
CN102680016A (en) * 2012-05-14 2012-09-19 北京理工大学 Error compensating method of photoelectric encoder
CN104460320A (en) * 2014-12-05 2015-03-25 西安理工大学 Circle shear overlap amount controller parameter optimizing method based on brainstorming
CN104614982A (en) * 2014-12-05 2015-05-13 西安理工大学 Method for adjusting overlap parameters of cycle shear based on multi-target brainstorming
CN107063091A (en) * 2017-04-11 2017-08-18 合肥工业大学 For big L/D ratio pipe fitting endoporus measuring multiple parameters device and method
CN112902877A (en) * 2021-01-15 2021-06-04 河南科技大学 Non-radial installation double-reading head circular grating angle measurement error correction method

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
LI: "Densification effects on the fracture in fused silica under Vickers indentation", 《CERAMICS INTERNATIONAL》 *
冯超鹏: "一种新的圆光栅偏心参数自标定方法", 《仪器仪表学报》 *
王笑一: "非对径安装双读数头圆光栅偏西测角误差修正", 《光学精密工程》 *

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