Evaluation Method for Uncertainties in Measuring the Speed, Distance and Three-Dimensional Topography of a Rotating Body

Abstract

The present invention discloses a method for evaluating the measurement uncertainties of the speed, distance, and three-dimensional topography of a rotating body. The measurement data of the speed and distance of the rotating body are arranged according to the rotation period, the direction of the rotation axis, and the circumferential direction. The uncertainties of the speed and distance are evaluated according to different rotation periods to eliminate the influence of the speckle effect, the spindle rotation error, and the roundness error of the object, and the uncertainty caused by noise is obtained. The uncertainties of the speed and distance are evaluated along the direction of the rotation axis to eliminate the interference of the spindle rotation error and the roundness error of the object itself on the uncertainty, and the uncertainty component caused by the speckle effect is obtained by combining the uncertainty component caused by noise, and then the total measurement uncertainties of the speed and distance are obtained. Based on the relationship between the surface speed and distance of the rotating body and the three-dimensional absolute topography, the uncertainty components caused by the speckle effect and noise are introduced to obtain the measurement uncertainty of the three-dimensional absolute topography. This method can make a more comprehensive and reasonable evaluation of the measurement uncertainty of the measurement system.

Description

Technical Field

[0001] The present invention relates to the field of measurement technology, and more particularly, to a method for evaluating the uncertainty of the speed, distance, and three-dimensional topography of a rotating body. Background Art

[0002] The existing uncertainty evaluation method only calculates the standard uncertainty of the measurement result, which cannot eliminate the interference of the spindle rotation error and the roundness error of the object itself on the measurement uncertainty in the measurement of the rotating body. Moreover, the existing evaluation method does not consider the uncertainty caused by factors such as the spindle speed and the speckle effect and its propagation to the total measurement uncertainty, resulting in a large error in the evaluation result of the measurement uncertainty. Summary of the Invention

[0003] In view of the technical problems raised in the above background art, a method for evaluating the uncertainty of the speed, distance, and three-dimensional topography of a rotating body is provided. The present invention mainly uses a new method for evaluating measurement uncertainty. This method can comprehensively consider and measure the influence of various uncertainty components on the final measurement result, and at the same time eliminate the interference of the spindle rotation error and the roundness error of the rotating body itself on the accuracy of the uncertainty evaluation, and is applicable to accurately evaluating the uncertainty of the measurement results of the surface speed, distance, and three-dimensional topography of rotating objects such as rotating workpieces and cutting tools in machine tools. The technical means adopted by the present invention are as follows:

[0004] A method for evaluating the uncertainty of the speed, distance, and three-dimensional topography of a rotating body, comprising the following steps:

[0005] Step 1: Arrange the measurement results of the surface speed v and the surface distance z of the rotating object obtained by laser velocity and distance measurement according to the rotation period, the rotation axis direction, and the circumferential direction of the rotating object, to obtain a data set containing N×M H ×M C elements, where N is the number of rotation periods, M H is the number of data arrangements in the rotation axis direction, and M C is the number of data arrangements in the circumferential direction; define n = 1, 2,..., N; h = 1, 2,..., M H ; i = 1, 2,..., M C ; where n, h, and i respectively represent the variables of the rotation period, the number of data arrangements in the rotation axis direction, and the number of data arrangements in the circumferential direction;

[0006] Step 2: Calculate the uncertainty of the surface speed v of the rotating object and the uncertainty of the surface distance z of the rotating object to remove the speckle effect, as well as the spindle rotation error and the object roundness error;

[0007] Step 3: Evaluate the velocity uncertainty component σ caused by noise according to the uncertainty obtained in Step 2 v,noise and the distance uncertainty component σ caused by noise z,noise ;

[0008] Step 4: Evaluate the uncertainty of velocity along the direction of the rotation axis and the uncertainty of distance

[0009] Step 5: Evaluate the uncertainty components σ caused by the speckle effect according to the uncertainties obtained in Step 3 and Step 4 v,speckle and σ z,speckle , and then obtain the total velocity measurement uncertainty and the total distance measurement uncertainty

[0010] Step 6: Based on the three-dimensional absolute topography relationship formula of the rotating body for velocity and distance measurement Obtain the three-dimensional absolute topography uncertainty σ r(h,i) , and then obtain the three-dimensional absolute topography measurement uncertainty σ r(h,i) .

[0011] Compared with the prior art, the present invention has the following advantages:

[0012] 1. The present invention proposes a mathematical model of a systematic measurement uncertainty relationship for the measurement of the surface velocity, distance, and three-dimensional absolute topography of a rotating object based on laser velocity and distance measurement technology. On the basis of the velocity and distance measurement uncertainties, it further includes the uncertainty components caused by the speckle effect, noise, and the uncertainty of the spindle rotation speed, and more comprehensively considers and measures the propagation of each uncertainty component and the number of measurements on the three-dimensional absolute topography measurement uncertainty, and obtains a complete uncertainty propagation equation.

[0013] 2. The present invention utilizes the generation characteristics of the spindle rotation error and the roundness error of the measured object itself during the measurement process, and eliminates the interference of the spindle rotation error and the roundness error of the object itself on the measurement uncertainty evaluation by evaluating the measurement uncertainties of velocity and distance along the direction of the rotation axis, making the evaluation result more reliable.

[0014] 3. The present invention utilizes the surface measurement point distribution characteristics during the rotation of the measured object, and realizes the evaluation of the uncertainty components caused by the speckle effect and noise by performing uncertainty evaluation on the measurement data in different directions on the surface, further expanding the evaluation method of measurement uncertainty. Description of the Drawings

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0016] Figure 1 It is a schematic diagram of the overall process of the present invention. Specific embodiments

[0017] In order to enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0018] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above accompanying drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily need to be limited to those clearly listed steps or units, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0019] As Figure 1 shown, the present invention provides a method for evaluating the uncertainties of the speed, distance, and three-dimensional topography of a rotating body, including the following steps:

[0020] Step 1: Arrange the measurement results of the surface speed v and the surface distance z of the rotating object obtained by laser speed and distance measurement according to the rotation period, rotation axis direction, and circumferential direction of the rotating object to obtain a data set containing N×M H ×M C elements, where N is the number of rotation periods, M H is the number of data arrangements in the rotation axis direction, and M C is the number of data arrangements in the circumferential direction; define n = 1, 2,..., N; h = 1, 2,..., M H ; i = 1, 2,..., M C; where n, h, and i are variables representing the rotation period, the number of data arrangements in the rotation axis direction, and the number of data arrangements in the circumferential direction, respectively.

[0021] Step 2: Calculate the uncertainty of the surface velocity v of the rotating object according to different rotation periods and the uncertainty of the distance where and are the means of the velocity and distance in the circumferential direction, and is the mean of and in the rotation axis direction. The uncertainty obtained in this step excludes the influence of the speckle effect, the spindle rotation error, and the roundness error of the object.

[0022] Step 3: Based on the uncertainty obtained in Step 2, evaluate the velocity uncertainty component caused by noise and the distance uncertainty component caused by noise

[0023] Step 4: Evaluate the uncertainty of the velocity and the uncertainty of the distance where and are the means of and in the rotation axis direction. The uncertainty obtained in this step excludes the influence of the spindle rotation error and the roundness error of the object, and at the same time includes the uncertainty caused by the speckle effect and noise.

[0024] Step 5: According to the uncertainties obtained in Step 3 and 4, evaluate the uncertainty components caused by the speckle effect and and then obtain the total velocity measurement uncertainty and the total distance measurement uncertainty

[0025] Step 6: Based on the three-dimensional absolute topography relationship of the rotating body for velocity and distance measurements where V is the mean velocity, Z is the mean distance, and ω is the rotational speed, obtain the three-dimensional absolute topography uncertainty where R is the average radius of the rotating body, σ ω is the uncertainty of the spindle rotational speed, introduce the uncertainty components caused by the speckle effect and noise, and obtain a more comprehensive three-dimensional absolute topography measurement uncertainty equation:

[0026] and then obtain the three-dimensional absolute topography measurement uncertainty σ r(h,i) .

[0027] Example 1

[0028] Arrange the measurement results of the surface velocity v and distance z of the rotating object obtained by laser velocimetry ranging according to the rotation period, the rotation axis direction, and the circumferential direction to obtain a data set containing N×M H ×M C elements; where N is the number of rotation periods, and M H is the number of data arrangements found on the rotation axis, and M C is the number of data arrangements in the circumferential direction;

[0029] Calculate the mean value of the velocity and the mean value of the distance in the circumferential direction, and then calculate the uncertainty of the velocity based on different rotation periods:

[0030]

[0031] and the uncertainty of the distance:

[0032]

[0033] where

[0034] the uncertainty obtained by this process excludes the influence of the speckle effect, the spindle runout error, and the roundness error of the object in equations (1) and (2).

[0035] Evaluate the uncertainty component caused by noise according to the uncertainty obtained by equations (1) and (2):

[0036]

[0037] and

[0038]

[0039] Evaluate the uncertainty of the velocity along the rotation axis direction:

[0040]

[0041] and the uncertainty of the distance:

[0042]

[0043] where

[0044] the uncertainty obtained by this process excludes the influence of the spindle runout error and the roundness error of the object, and at the same time includes the uncertainty caused by the speckle effect and noise in equations (5) and (6).

[0045] Evaluate the uncertainty component caused by the speckle effect according to the uncertainties obtained from Equations (3) to (6):

[0046]

[0047] and

[0048]

[0049] Calculate the total velocity measurement uncertainty according to the uncertainty components caused by noise and speckle effect obtained from Equations (3), (4), (7), and (8):

[0050]

[0051] and the total distance measurement uncertainty:

[0052]

[0053] Three-dimensional absolute shape relationship of a rotating body based on velocity and distance measurements where V is the average velocity and Z is the average distance, and the three-dimensional absolute shape uncertainty is derived as:

[0054]

[0055] where R is the average radius of the rotating body, and σ ω is the uncertainty of the spindle speed. By introducing the uncertainty components caused by the speckle effect and noise, a more comprehensive three-dimensional absolute shape measurement uncertainty equation is obtained:

[0056]

[0057] Obtain the three-dimensional absolute shape measurement uncertainty σ r(h,i) .

[0058] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments.

[0059] In the above embodiments of the present invention, the descriptions of the respective embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0060] In several embodiments provided by the present application, it should be understood that the disclosed technical content can be implemented in other ways.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. Evaluation method for the uncertainty of the speed, distance and three-dimensional topography of a rotating body, characterized in that, it includes the following steps: Step 1: Arrange the measurement results of the surface velocity v and the surface distance z of the rotating object obtained by laser velocity and distance measurement according to the rotation period, the rotation axis direction, and the circumferential direction of the rotating object, to obtain a data set containing N×M H ×M C elements, where N is the number of rotation periods, M H is the number of data arrangements in the rotation axis direction, and M C is the number of data arrangements in the circumferential direction; define n = 1, 2, …, N; h = 1, 2, …, M H ; i = 1, 2, …, M C ; where n, h, and i respectively represent the variables of the rotation period, the number of data arrangements in the rotation axis direction, and the number of data arrangements in the circumferential direction; Step 2: Calculate the uncertainty of the surface velocity v of the rotating object according to different rotation periods and the uncertainty of the distance z from the surface of the rotating object Step 3: Evaluate the velocity uncertainty component σ caused by noise based on the uncertainty obtained in Step 2 v,noise and the distance uncertainty component σ caused by noise z,noise ; Step 4: Evaluate the uncertainty of velocity along the direction of the rotation axis and the uncertainty of distance Step 5: Evaluate the uncertainty components σ v,speckle and σ z,speckle caused by the speckle effect according to the uncertainties obtained in Step 3 and Step 4, and further obtain the total velocity measurement uncertainty and the total distance measurement uncertainty Step 6: Three-dimensional absolute topography relational expression based on speed and distance measurement Obtain the three-dimensional absolute topography uncertainty σ r(h,i) , and then obtain the three-dimensional absolute topography measurement uncertainty σ r(h,i) .

2. The evaluation method for the uncertainty of the speed, distance and three-dimensional topography of a rotating body according to claim 1, characterized in that, the uncertainty of the surface speed v of the rotating object is: and the uncertainty of the distance to the surface of the rotating object is: Among them, and respectively represent the average values of the velocity and distance in the circumferential direction; and respectively represent the and average values in the direction of the rotation axis; n and h respectively represent the variables of the rotation period and the number of data arrangements in the direction of the rotation axis.

3. The evaluation method for the uncertainty of the speed, distance and three-dimensional topography of a rotating body according to claim 1, characterized in that, The velocity uncertainty component σ caused by the noise v,noise is as follows: The distance uncertainty component σ caused by noise z,noise Among them, M H is the number of data arrangements in the rotation axis direction, and M C is the number of data arrangements in the circumferential direction.

4. The evaluation method for the uncertainty of the speed, distance and three-dimensional topography of a rotating body according to claim 1, characterized in that, The uncertainty of the velocity along the direction of the rotation axis is as follows: The uncertainty of the said distance is as follows: Wherein, and respectively represent the means in the directions of the rotation axes and of.

5. The evaluation method for the uncertainty of the speed, distance and three-dimensional topography of a rotating body according to claim 1, characterized in that, The uncertainty components σ v,speckle and σ z,speckle caused by the evaluated speckle effect are respectively as follows:

6. The evaluation method for the uncertainty of the speed, distance and three-dimensional topography of a rotating body according to claim 1, characterized in that, The three-dimensional absolute profile uncertainty σ r(h,i) is as follows: where R represents the average radius of the rotating body, σ ω represents the uncertainty of the spindle speed, and by introducing the uncertainty components caused by the speckle effect and noise, a more comprehensive three-dimensional absolute topography measurement uncertainty equation is obtained. V represents the average velocity, Z represents the average distance, and ω represents the rotational speed.

7. The evaluation method for the uncertainty of the speed, distance and three-dimensional topography of a rotating body according to claim 1, characterized in that, The three-dimensional absolute profile measurement uncertainty σ r(h,i) is as follows:

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