Deflection angle detection system and method of displacement execution device and deflection angle compensation method

Abstract

The invention discloses a deflection angle detection system and method of a displacement execution device and a deflection angle compensation method, and the system comprises a reference assembly which is disposed on a moving part of the displacement execution device and is used for following the moving part to move from a first position to a second position; the reference assembly is provided with at least one reference surface, and a preset angle is formed between the reference surface and the theoretical movement axial direction of the displacement execution device; the measuring device is used for measuring the detection distances between the reference surface and the measuring point when the reference surface is located at the first position and the second position; and the processor is used for calculating the actual angle between the actual movement axial direction of the displacement execution device and the reference surface according to the detection distance and the movement distance between the first position and the second position, and obtaining the deviation angle of the actual movement axial direction relative to the theoretical movement axial direction under the condition relative to the reference surface based on the actual angle and a preset angle. According to the method, the deviation angle of the reference surface corresponding to the displacement execution device can be calculated, and measurement parameters are provided for subsequent adjustment and calibration.

Description

Technical Field

[0001] The present invention relates to the technical field of displacement actuator detection, and in particular to a displacement actuator deflection detection system, method and deflection compensation method. Background Art

[0002] In the field of displacement actuators (such as drivers and push rods), there is an angular deviation between the actual axial movement of the moving part (such as telescopic rods and shafts) of the displacement actuator and the theoretical axial movement due to machining accuracy.

[0003] In the field of detection, a displacement actuator is required to drive the movement of the object to be tested or the image detector. The real-time position of the object to be tested or the image detector needs to be calculated based on the output of the displacement actuator. When the above-mentioned angle deviation exists, there will be errors in the position calculation. In order to improve the accuracy of the position calculation, it is necessary to determine the axial angle deviation of the displacement actuator to facilitate the subsequent compensation of the displacement parameters.

[0004] Therefore, how to detect the axial angle deviation of the displacement actuator is a problem that needs to be solved. Summary of the invention

[0005] The main technical problem solved by the present invention is that there is an angular deviation between the actual movement axis and the theoretical movement axis of the existing displacement actuator, which needs to be detected.

[0006] According to the first aspect, an embodiment provides a deflection angle detection system for a displacement actuator, comprising:

[0007] A reference component is provided on the moving part of the displacement actuator and is used to follow the moving part to move from the first position to the second position; the reference component has at least one reference surface, and a preset angle is formed between the reference surface and the theoretical movement axis of the displacement actuator;

[0008] A measuring device, used to measure the detection distance between the reference surface and the measuring point when the reference surface is located at the first position and the second position respectively;

[0009] The processor is used to calculate the actual angle between the actual movement axis of the displacement actuator and the reference surface according to the detection distance and the movement distance between the first position and the second position, and based on the actual angle and the preset angle, obtain the deviation angle of the actual movement axis relative to the theoretical movement axis under the condition relative to the reference surface.

[0010] According to the second aspect, an embodiment provides a method for detecting an angle of deflection of a displacement actuator, comprising:

[0011] Obtaining a movement distance of a moving part of the displacement actuator from a first position to a second position in an actual movement axis direction; wherein a reference component is provided on the moving part, the reference component has a reference surface, and the reference has a preset angle with the theoretical movement axis direction of the displacement actuator;

[0012] Acquire the detection distances of the reference surface from the measurement point when the reference surface is located at the first position and the second position respectively;

[0013] Calculate the actual angle between the actual moving axis of the displacement actuator and the reference surface according to the detection distance and the moving distance;

[0014] According to the actual angle and the preset angle, the deviation angle of the actual motion axis relative to the theoretical motion axis under the condition of relative to the reference surface is obtained.

[0015] According to the third aspect, an embodiment provides a method for compensating for an angle of deflection of a displacement actuator, wherein the displacement actuator has an identification direction, and the identification direction is used to identify a theoretical motion axis of the displacement actuator;

[0016] Compensation methods include:

[0017] According to the deflection angle detection method described in the second aspect of the claim, the deviation angle of the actual movement axis of the displacement actuator relative to the theoretical movement axis relative to the reference surface is obtained;

[0018] Adjust the position of the displacement actuator to make the marking direction deflect in the opposite direction by the deviation angle;

[0019] Alternatively, the spatial coordinate position of the moving part of the displacement actuator is corrected based on the deviation angle.

[0020] According to the deflection detection system, method and deflection compensation method of the displacement actuator of the above-mentioned embodiment, by installing a reference component on the moving part of the displacement actuator and measuring the detection distance of the reference surface of the reference component corresponding to the first position and the second position of the moving part, the deviation angle of the actual movement axis of the displacement actuator relative to the theoretical movement axis with respect to the reference surface can be calculated. That is, the deviation angle of the displacement actuator in a direction (corresponding to the reference surface) can be calculated, which provides measurement parameters for subsequent adjustment and calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of the structure of a deflection detection system provided by an embodiment of the present application;

[0022] Figure 2 A schematic diagram of the structure of a reference component provided for an embodiment of the present application;

[0023] Figure 3 A schematic diagram of the actual movement axis provided by an embodiment of the present application;

[0024] Figure 4 A schematic diagram of a first deviation angle and a second deviation angle provided in an embodiment of the present application;

[0025] Figure 5 A schematic diagram of a first actual angle provided for an embodiment of the present application;

[0026] Figure 6 A schematic diagram of a first deviation distance provided in an embodiment of the present application;

[0027] Figure 7 A schematic diagram of a second actual angle provided for an embodiment of the present application;

[0028] Figure 8 A schematic diagram of a second deviation distance provided in an embodiment of the present application;

[0029] Fig. 9 A flowchart of a method for detecting an angle of deflection provided in one embodiment of the present application (I);

[0030] Fig.10 Flow chart of a method for detecting an angle of deviation provided in one embodiment of the present application (II);

[0031] Fig.11 A flowchart of a method for angle compensation provided in one embodiment of the present application.

[0032] Reference numerals: 10 - displacement actuator; 200 - reference assembly; 20 - reference plane; 21 - first reflection plane; 22 - second reflection plane; 30 - measuring device; 40 - processor. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below by specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments adopt associated similar element numbers. In the following embodiments, many detailed descriptions are for making the present application better understood. However, those skilled in the art can easily recognize that some features can be omitted in different situations, or can be replaced by other elements, materials, methods. In some cases, some operations related to the present application are not shown or described in the specification, this is to avoid the core part of the present application being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations according to the description in the specification and the general technical knowledge in the art.

[0034] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various implementations. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a required sequence, unless otherwise specified that a certain sequence must be followed.

[0035] The serial numbers of the components in this document, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings).

[0036] In the field of optical detection, when it comes to light path adjustment or the movement of optical components, displacement actuators are generally used for driving. In high-precision optical detection, the general movement accuracy needs to reach the micron level or even sub-nanometer level. For displacement actuators, there must be a random deviation angle between the actual movement axis of its moving part and the theoretical movement axis.

[0037] On the other hand, during use, there are usually high requirements for the installation of the moving axis of the displacement actuator. If the moving axis of the displacement actuator is inconsistent with the ideal installation direction, even if the driver itself has high linearity, lateral deviation will still occur during movement. The displacement actuator usually has a reference direction (which can be called the theoretical moving axis) marked in the external structure as a reference for installation and adjustment. However, for high-precision requirements of <0.01°, mechanical tolerances are often difficult to guarantee. In addition, using a displacement meter to measure the axial offset of the motion process and then calculate the angular deviation is a conventional detection method, but the displacement meter cannot measure errors corresponding to the micron or even sub-nanometer level.

[0038] For example, taking piezoelectric ceramic drivers as an example, piezoelectric ceramic drivers have the advantages of high resolution and good stability, can achieve sub-nanometer repeatability, and are widely used in high-precision optical detection. Piezoelectric ceramic driver devices can be single-axis or multi-axis motion. There may be a slight angular deviation between the direction of the motion axis marked on the device and the actual direction of the motion axis. Even a deviation at the millisecond radian level will affect the motion adjustment of the optical element. However, assuming a driver with a total stroke of <100um, there is an axial tilt of 0.01°, which can only introduce a radial offset of 17.45nm, which is difficult to detect with conventional methods such as displacement meters.

[0039] Therefore, it is necessary to measure the deviation angle between the actual movement axis and the theoretical movement axis of the moving part of the displacement actuator and calibrate its movement angle to provide a reference for subsequent installation on the detection equipment and ensure the accuracy and quality of optical detection.

[0040] It should be noted that the theoretical movement axis of the moving part of the displacement actuator can be the movement direction marked at the factory, which is used as the base direction or reference direction for device installation. Usually, the theoretical movement axis is very close to the actual movement direction of the moving part (i.e., the actual movement axis). However, for applications with high precision requirements, the angular error caused by this directional proximity cannot be tolerated. Therefore, it is necessary to detect this tiny angular error in order to perform motion compensation for the moving part.

[0041] like Figure 1 As shown, an embodiment of the present application provides a system for detecting an angle of deflection of a displacement actuator 10 , which may include: a reference component 200 , a measuring device 30 , and a processor 40 .

[0042] The reference component 200 is disposed on the moving part of the displacement actuator 10 and is used to follow the moving part to move from the first position to the second position. The reference component 200 has at least one reference surface, and there is a preset angle between the reference surface and the theoretical movement axis of the displacement actuator 10.

[0043] In some embodiments, the reference component 200 may have three reference surfaces, one of which serves as a reference surface 20 and one of which serves as a first reflection surface 21. The reference surface 20 and the first reflection surface 21 have a preset component angle relationship. When the reference component 200 is installed on the moving part, the first reflection surface 21 has a first preset angle with the theoretical movement axis of the displacement actuator 10.

[0044] For example, Figure 2 As shown, the reference plane 20 of the reference component 200 and the first reflection surface 21 can be vertically arranged. When the reference component 200 is installed on the moving part, the reference plane 20 is perpendicular to the theoretical movement axis of the displacement actuator 10, and the first preset angle corresponds to 0°.

[0045] The measuring device 30 is configured to measure the detection distance of the reference surface from the measuring point when it is located at the first position and the second position, respectively. For example, the measuring device 30 can be a laser rangefinder, an interferometer, etc. When performing distance measurement at the micron level, it can be achieved by using a laser rangefinder or an interferometer; and when measuring at the sub-nanometer level or nanometer level, it can be achieved by using an interferometer. For example, the first position can correspond to the position where the stroke of the displacement actuator 10 is zero, and the second position corresponds to the position where the stroke is the largest. At this time, regardless of measuring the detection distance of the corresponding measuring point of the first reflective surface 21 or the second reflective surface 22, the first position and the second position can be reproduced to ensure the control variable of the measurement.

[0046] The processor 40 is configured to calculate the actual angle between the actual moving axis of the displacement actuator 10 and the reference plane based on the detection distance and the moving distance between the first position and the second position, and obtain the deviation angle of the actual moving axis relative to the theoretical moving axis under the condition of relative to the reference plane based on the actual angle and the preset angle. The processor 40 is used to control the operation of the displacement actuator 10 on the one hand, and to calculate based on the measurement data provided by the measuring device 30 on the other hand to obtain the above deviation angle.

[0047] For example, a reference surface of the reference component is configured as a first reflection surface, and the first reflection surface has a first preset angle with the theoretical movement axis of the displacement actuator.

[0048] The measuring device is configured at a first measuring point, which is arranged opposite to the first reflecting surface, and is used to measure a first detection distance from the first measuring point when the first reflecting surface is located at a first position and a second position respectively.

[0049] The processor is configured to calculate the difference of the first detection distance to obtain a first deviation distance caused by the moving part moving from the first position to the second position in the actual moving axis, and calculate the first actual angle between the actual moving axis and the first reflecting surface according to the first deviation distance and the moving distance; based on the first actual angle and the first preset angle, obtain the first deviation angle of the actual moving axis relative to the theoretical moving axis under the condition relative to the first reflecting surface.

[0050] In actual use, according to the needs of optical detection, there is a situation where the motion deviation in one direction is only concerned. In this case, it is only necessary to detect the deviation angle of the displacement motion actuator in this direction. Figure 3 and Figure 4As shown, taking the XYZ geometric coordinate system of the displacement motion actuator as an example, the theoretical motion axis of the moving part of the displacement motion actuator is parallel to the Z axis, and the actual motion axis has a first deviation angle θ1 and a second deviation angle θ2 with the XZ plane and the YZ plane. If, in the optical detection project, only the first deviation angle θ1 relative to the XZ plane is concerned, then the second deviation angle θ2 relative to the YZ plane does not need to be calculated.

[0051] In order to realize the measurement of the first deviation angle θ1, the present application installs a reference component 200 on the moving part, and the reference component 200 also has an xyz geometric coordinate system, and a reference surface is configured as a first reflection surface 21. By measuring the first actual angle θx between the actual moving axis and the first reflection surface 21, it is necessary to set the first reflection surface 21 to be parallel to the XZ plane. Combined with the conversion relationship between the xyz geometric coordinate system and the XYZ geometric coordinate system, the first deviation angle θ1 can be calculated.

[0052] In actual measurement, Figure 5 As shown, theoretically, when the moving part moves from the first position to the second position, the first reflection surface 21 of the reference component 200 moves from point x0 to point x2, but due to the existence of the first deviation angle, the first reflection surface 21 moves from point x0 to point x1, and the movement interval is L. The first detection distances of the first reflection surface at the first position and the second position from the first measurement point are measured by the measuring device 30, and the first deviation distance Dx generated by the first reflection surface 21 when the moving part moves from the first position to the second position is calculated according to the difference of the first detection distances corresponding to the two positions, and the first actual angle θx between the actual movement axis and the first reflection surface 21 can be calculated by the triangular function. Then, according to the first actual angle θx and the first preset angle (that is, obtained according to the spatial relationship between the XYZ coordinate system and the xyz coordinate system), the first deviation angle θ1 of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis with respect to the first reflection surface 21 is obtained.

[0053] For example, when the reference plane 20 is perpendicular to the theoretical motion axis Z axis, and the first reflection plane 21 is parallel to the XZ plane, the first actual angle θx measured at this time is equal to the first deviation angle θ1.

[0054] In one embodiment, the optical detection needs to focus on the third deviation angle of the moving part in space, not just the first deviation angle or the second deviation angle. Figure 2As shown, the reference component 200 may also have another reference surface configured as a second reflection surface 22, and the reference surface 20, the first reflection surface 21, and the second reflection surface 22 have a preset component angle relationship between each other; when the reference component 200 is installed on the moving part, the second reflection surface 22 has a second preset angle with the theoretical motion axis of the displacement actuator 10. Generally, in order to simplify the calculation, the second reflection surface 22 is set to be parallel to the theoretical motion axis, and the second preset angle is 0°.

[0055] like Figure 7 As shown, the measuring device 30 is also configured at a second measuring point, which is arranged opposite to the second reflecting surface, and is used to measure a second detection distance relative to the second measuring point when the second reflecting surface is located at the first position and the second position respectively.

[0056] The processor 40 is further configured to obtain a second deviation distance Dy generated when the moving part moves from the first position to the second position in the actual moving axis according to the difference of the second detection distances corresponding to the two positions. According to the second deviation distance Dy, a second actual angle θy between the actual moving axis and the second reflecting surface 22 is calculated; and according to the second actual angle and the second preset angle, a second deviation angle of the actual moving axis of the displacement actuator 10 relative to the theoretical moving axis relative to the second reflecting surface 22 is obtained.

[0057] According to the first deviation angle θ1 and the second deviation angle θ2, a third deviation angle of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis with respect to the reference plane 20 is obtained.

[0058] Similarly, if Figure 7 and Figure 8 As shown, in combination with the second reflecting surface 22, the second deviation angle θ2 of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis in the YZ plane direction can be calculated, and in combination with the first deviation angle θ1, the third deviation angle θ3 of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis in three-dimensional space can be calculated.

[0059] Generally, the displacement actuator 10 will be provided with relevant information such as identification direction, which is used to indicate the theoretical movement axis of the current displacement actuator 10. The present application combines the above-mentioned deviation angles (the first deviation angle θ1, the second deviation angle θ2 and the third deviation angle θ3) as a reference for adjustment, thereby improving the control accuracy of the moving part of the displacement actuator 10 and ensuring the quality of optical detection.

[0060] In one embodiment, in order to simplify the calculation, the first reflection surface 21 may be perpendicular to the reference surface 20, the second reflection surface 22 may be perpendicular to the reference surface 20, and the reference surface 20 is perpendicular to the theoretical motion axis of the displacement actuator 10. Furthermore, the first reflection surface 21 may also be perpendicular to the second reflection surface 22. In this case, the reference assembly 200 may be an absolutely vertical reflection mirror combination.

[0061] In one embodiment, the reference component 200 can be a corner reflector (or a hollow retroreflector), which has three mutually perpendicular reflecting surfaces, one reflecting surface serving as a reference surface 20, and the other two reflecting surfaces serving as a first reflecting surface 21 and a second reflecting surface 22, respectively. The reference surface 20 is perpendicular to the theoretical movement axis of the displacement actuator 10, and the first reflecting surface 21 and the second reflecting surface 22 are both parallel to the theoretical movement axis of the displacement actuator 10.

[0062] When the first reflecting surface 21 and the second reflecting surface 22 are respectively parallel to the theoretical motion axis, and the first reflecting surface 21 is parallel to the XZ plane of the displacement actuator 10, the calculated first actual angle can be directly used as the first deviation angle, and the second actual angle can be used as the second deviation angle, thereby reducing the calculation workload.

[0063] In one embodiment, the displacement actuator 10 may be a piezoelectric driver, the processor 40 may be a corresponding drive processor, and the processor 40 outputs a movement distance from the first position to the second position.

[0064] The processor 40 calculates a first deviation angle between the actual movement axis and the first reflecting surface 21 based on the first deviation distance and the movement spacing; calculates a second deviation angle between the actual movement axis and the second reflecting surface 22 based on the second deviation distance and the movement spacing; and calculates a third deviation angle of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis relative to the reference plane 20 based on the first deviation angle, the second deviation angle and the component angle relationship.

[0065] In the current field of optical detection, piezoelectric drivers (such as piezoelectric PZT elements) are commonly used displacement actuators 10. Piezoelectric drivers require a corresponding processor 40 to achieve motion control, and the motion spacing can be obtained through the processor 40. Based on the processor 40 of the piezoelectric driver, the present application outputs the measurement parameters of the measuring device 30, and the deviation angle can be calculated by the processor 40.

[0066] In one embodiment, corresponding to high-precision optical detection, the theoretical maximum value of the deviation angle of the moving axis of the displacement actuator 10 is less than or equal to 0.01°, and the measuring device 30 may include a laser interferometer or a white light interferometer. The laser interferometer or the white light interferometer is used to emit a detection beam to the reference surface and receive a reflected beam generated by the reference surface, and obtain a detection distance between the reference surface and the measurement point by analyzing the reflected beam.

[0067] For example, the laser interferometer can emit laser light directly at a certain surface of the corner reflector. The reflected laser light on a certain surface of the corner reflector interferes with the emitted laser light and the interference fringes are measured by the laser interferometer. The distance from the laser interferometer to a certain surface of the corner reflector is calculated based on the change of the interference fringes, which can achieve sub-nanometer or even nanometer-level precise measurement. When it is necessary to measure other surfaces of the corner reflector, it is only necessary to adjust the position of the laser interferometer.

[0068] The following is an explanation of the specific process of the angle detection method performed by the angle detection system. Fig. 9 As shown, the angle detection method may include the following steps:

[0069] Step 1, obtaining the movement distance of the moving part of the displacement actuator from the first position to the second position in the actual movement axis; wherein a reference component is provided on the moving part, the reference component has a reference surface, and the reference has a preset angle with the theoretical movement axis of the displacement actuator.

[0070] Step 2: Obtain the detection distances of the reference surface from the measurement point when the reference surface is located at the first position and the second position, respectively.

[0071] Step 3: Calculate the actual angle between the actual moving axis of the displacement actuator and the reference surface based on the detection distance and the moving distance.

[0072] Step 4: Based on the actual angle and the preset angle, obtain the deviation angle of the actual motion axis relative to the theoretical motion axis under the condition of relative to the reference surface.

[0073] For example, when a reference surface of the reference component is configured as a first reflection surface, the above steps 2 to 4 may include steps 201 to 401 correspondingly.

[0074] In step 201, a first detection distance between a first reflective surface and a first measuring point is measured when the first reflective surface is located at a first position and a second position, respectively.

[0075] Among them, step 301, calculate the difference of the first detection distance to obtain the first deviation distance generated by the moving part moving from the first position to the second position in the actual moving axis; calculate the first actual angle between the actual moving axis and the first reflecting surface according to the first deviation distance and the moving distance.

[0076] In step 401, based on the first actual angle and the first preset angle, a first deviation angle of the actual moving axis relative to the theoretical moving axis under the condition of being relative to the first reflecting surface is obtained.

[0077] For example, Figure 3 As shown, when the moving part moves from the first position to the second position, as shown in Figure 5 and Figure 6 As shown, theoretically, the first reflection surface 21 of the reference component 200 moves from point x0 to point x2, but due to the existence of the first deviation angle, the first reflection surface 21 moves from point x0 to point x1, and the movement distance is L. The first detection distances corresponding to the first position and the second position of the first reflection surface 21 are measured by the measuring device 30, and the first deviation distance Dx generated when the moving part moves from the first position to the second position is calculated according to the difference of the first detection distance, and the first actual angle θx between the actual movement axis and the first reflection surface 21 can be calculated by the triangular function. Then, according to the first actual angle θx and the first preset angle, the first deviation angle θ1 of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis with respect to the first reflection surface 21 is obtained.

[0078] In one embodiment, the reference component 200 may also have another reference surface configured as a second reflective surface 22, and the reference surface 20, the first reflective surface 21, and the second reflective surface 22 have a preset component angle relationship between each other; the second reflective surface 22 has a second preset angle with the theoretical motion axis of the displacement actuator 10. The component angle relationship is determined according to the actual situation of the reference component 200. Generally, optical elements such as calibrated standard corner reflectors can be directly used, and the angle between each reflective surface is determined.

[0079] like Fig.10 As shown, the angle detection method may further include:

[0080] Step 5: Measure a second detection distance of the second reflective surface relative to the second measuring point when the second reflective surface is located at the first position and the second position respectively.

[0081] Step 6: Calculate the difference of the second detection distance to obtain a second deviation distance generated when the moving part moves from the first position to the second position in the actual moving axis.

[0082] Step 7: Calculate a second actual angle between the actual movement axis and the second reflection surface according to the second deviation distance and the movement spacing.

[0083] Step 8: According to the second actual angle and the second preset angle, a second deviation angle of the actual movement axis of the displacement actuator relative to the theoretical movement axis relative to the second reflection surface is obtained.

[0084] For example, Figure 3 As shown, when the moving part moves from the first position to the second position, as shown in Figure 7 and Figure 8 As shown, theoretically, the second reflection surface 22 of the reference component 200 moves from point y0 to point y2, but due to the existence of the second deviation angle, the second reflection surface 22 moves from point y0 to point y1, and the movement distance is L. The second deviation distance Dy generated by the second reflection surface 22 when the moving part moves from the first position to the second position is measured by the measuring device 30, and the second actual angle θy between the actual movement axis and the second reflection surface 22 can be calculated by the trigonometric function. Then, according to the second actual angle θy and the second preset angle, the second deviation angle θ2 of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis with respect to the second reflection surface 22 is obtained.

[0085] In one embodiment, in step 2, obtaining the detection distances of the reference surface from the measurement point when the reference surface is located at the first position and the second position respectively may include:

[0086] When the moving part is at the first position, the first distance between the first measuring point and the first reflecting surface 21 is obtained, and when the moving part is at the second position, the second distance between the first measuring point and the first reflecting surface 21 is obtained; the first deviation distance is the difference between the first distance and the second distance. In other words, the first detection distance includes the above-mentioned first distance and second distance.

[0087] like Figure 6 As shown, when the moving part is located at the first position, the first distance Dx0 between the first measuring point and the first reflecting surface 21 is obtained, and when the moving part is located at the second position, the second distance Dx1 between the first measuring point and the first reflecting surface 21 is obtained; the first deviation distance Dx is the difference between the first distance Dx0 and the second distance Dx1, that is, Dx=|Dx0-Dx1|.

[0088] In one embodiment, in step 5, measuring the second detection distance of the second reflective surface relative to the second measurement point when the second reflective surface is located at the first position and the second position respectively may include:

[0089] When the moving part is at the first position, the third distance between the second measuring point and the second reflecting surface 22 is obtained, and when the moving part is at the second position, the fourth distance between the second measuring point and the second reflecting surface 22 is obtained; the second deviation distance is the difference between the third distance and the fourth distance. In other words, the second detection distance includes the third distance and the fourth distance.

[0090] like Figure 8As shown, when the moving part is located at the first position, the first distance Dy0 between the second measuring point and the second reflecting surface 22 is obtained, and when the moving part is located at the second position, the second distance Dy1 between the second measuring point and the second reflecting surface 22 is obtained; the second deviation distance Dy is the difference between the first distance Dy0 and the second distance Dy1, that is, Dy=|Dy0-Dy1|.

[0091] In one embodiment, in step 3, calculating the actual angle between the actual movement axis of the displacement actuator and the reference surface according to the detection distance and the movement spacing may include:

[0092] The difference of the first detection distance is calculated to obtain a first deviation distance generated when the moving part moves from the first position to the second position in the actual moving axis; and the first actual angle between the actual moving axis and the first reflective surface is calculated according to the first deviation distance and the moving distance. The moving distance L can be calculated by reading the parameters of the processor 40 and using trigonometric functions to perform angle calculation.

[0093] For example, the first actual angle θx is calculated according to the following formula:

[0094] or In fact, the first deviation angle θ1 is very small. When the first reflection surface 21 is set to be parallel to the theoretical motion axis, the first actual angle θx is equal to the first deviation angle θ1. At this time, Figure 5 As shown, When θ1 is very small,

[0095] Wherein, Dx0 is the first distance between the first measuring point and the first reflecting surface 21 when the moving part is located at the first position; Dx1 is the second distance between the first measuring point and the first reflecting surface 21 when the moving part is located at the second position; and L is the moving distance.

[0096] In one embodiment, in step 7, calculating the second actual angle between the actual movement axis and the second reflection surface according to the second deviation distance and the movement spacing may include:

[0097] The difference of the second detection distance is calculated to obtain a second deviation distance generated when the moving part moves from the first position to the second position in the actual moving axis; and the second actual angle between the actual moving axis and the second reflecting surface is calculated according to the second deviation distance and the moving distance.

[0098] For example, the second actual angle θy is calculated according to the following formula:

[0099] or In fact, the second deviation angle θ2 is very small. When the second reflecting surface 22 is set to be parallel to the theoretical motion axis, the second actual angle θy is equal to the second deviation angle θ2 is very small. At this time, Figure 8 As shown, When θ2 is very small,

[0100] Wherein, Dy0 is the third distance between the second measuring point and the second reflecting surface 22 when the moving part is located at the first position; Dy1 is the fourth distance between the second measuring point and the second reflecting surface 22 when the moving part is located at the second position; and L is the moving distance.

[0101] In the above embodiment, in step 6, obtaining a third deviation angle of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis relative to the reference plane 20 according to the first deviation angle and the second deviation angle may include:

[0102] According to the first deviation angle, the second deviation angle and the component angle relationship, a third deviation angle of the actual movement axis of the displacement actuator 10 relative to the theoretical movement axis with respect to the reference plane 20 is calculated.

[0103] In one embodiment, the first reflection surface 21 is perpendicular to the reference surface 20, the second reflection surface 22 is perpendicular to the reference surface 20, the reference surface 20 is perpendicular to the theoretical motion axis of the displacement actuator 10; the first reflection surface 21 is perpendicular to the second reflection surface 22. Alternatively, the reference component 200 is a corner reflector, and the corner reflector has three reflection surfaces, one of which serves as the reference surface 20, and the other two reflection surfaces serve as the first reflection surface 21 and the second reflection surface 22. At this time, the angle relationship of the above components is the simplest, and the reference surface 20 can be directly perpendicular to the theoretical motion axis, and the third deviation angle can be obtained.

[0104] In one embodiment, the theoretical maximum value of the deviation angle of the moving axis of the displacement actuator 10 is less than or equal to 0.01°; a laser interferometer or a white light interferometer is used to measure the first detection distance and the second detection distance.

[0105] like Fig.11 As shown, the embodiment of the present application further provides a method for compensating the deflection angle of a displacement actuator 10 , wherein the displacement actuator has an identification direction, and the identification direction is used to identify the direction of the theoretical movement axis of the displacement actuator.

[0106] Compensation methods may include:

[0107] Step 9: According to the angle detection method in the above embodiment, the deviation angle of the actual movement axis of the displacement actuator relative to the theoretical movement axis relative to the reference surface is obtained.

[0108] Step 10: Adjust the position of the displacement actuator to make the marking direction deflect in the opposite direction by the deviation angle. The position of the displacement actuator can be adjusted by compensating the deviation angle so that the actual movement axis of the displacement actuator after adjustment is consistent with the required movement direction, ensuring the accuracy of displacement control and the quality of optical detection.

[0109] Alternatively, the spatial coordinate position of the moving part of the displacement actuator is corrected based on the deviation angle.

[0110] For example, in optical detection, it is generally necessary to collect the detection image through an image detector. Some implementation methods are to drive the test piece to move so that the image detector traverses the test piece; other implementation methods are to drive the image detector to move so that the image detector traverses the test piece; in some implementation methods, the detection area is changed by driving the optical component to change the optical path of the image detector. Regardless of which implementation method is used, a displacement actuator needs to be used as the driving source. At this time, the deviation angle of the moving part will cause the detection accuracy, such as inaccurate positioning, inaccurate optical path and other problems. At this time, it is necessary to compensate the spatial position of the moving part according to the deviation angle to achieve high-precision optical detection.

[0111] In summary, the deflection detection system, method and deflection compensation method of the displacement actuator provided in the embodiments of the present application, by installing a reference component on the moving part of the displacement actuator, calculates the first deviation distance generated by the first reflection surface of the reference component when the moving part moves from a first position to a second position, and can calculate the first deviation angle of the actual movement axis of the displacement actuator relative to the theoretical movement axis relative to the first reflection surface. That is, the deviation angle of the displacement actuator in one direction (corresponding to the first reflection surface) can be calculated, and the second deviation angle in another direction and the third deviation angle in the spatial position can also be calculated, which provide measurement parameters for subsequent adjustment and calibration.

[0112] The deflection detection method and compensation method provided in the present application can be implemented by a terminal device, which may include a memory and a processor. For example, the terminal device may be a computer, a server, or other device with computing and data processing capabilities.

[0113] The memory is used to store programs. The processor is used to implement the angle detection method and compensation method described in the above embodiments by executing the programs stored in the memory.

[0114] Those skilled in the art will appreciate that all or part of the functions of the various methods in the above-mentioned embodiments can be implemented by hardware or by computer programs. When all or part of the functions in the above-mentioned embodiments are implemented by computer programs, the program can be stored in a computer-readable storage medium, and the storage medium can include: read-only memory, random access memory, disk, optical disk, hard disk, etc., and the program is executed by a computer to implement the above-mentioned functions. For example, the program is stored in the memory of the device, and when the program in the memory is executed by the processor, all or part of the above-mentioned functions can be implemented. In addition, when all or part of the functions in the above-mentioned embodiments are implemented by computer programs, the program can also be stored in a storage medium such as a server, another computer, disk, optical disk, flash disk or mobile hard disk, and can be downloaded or copied and saved in the memory of the local device, or the system of the local device is updated, and when the program in the memory is executed by the processor, all or part of the functions in the above-mentioned embodiments can be implemented.

[0115] This document is described with reference to various exemplary embodiments. However, those skilled in the art will recognize that changes and modifications may be made to the exemplary embodiments without departing from the scope of this document. For example, various operating steps and components for performing the operating steps may be implemented in different ways (e.g., one or more steps may be deleted, modified, or incorporated into other steps) depending on the specific application or considering any number of cost functions associated with the operation of the system.

[0116] Although the principles of this invention have been shown in various embodiments, many modifications of structures, arrangements, proportions, elements, materials and components particularly suitable for specific environments and operational requirements can be used without departing from the principles and scope of this invention. The above modifications and other changes or amendments will be included in the scope of this invention.

[0117] The foregoing specific description has been described with reference to various embodiments. However, those skilled in the art will recognize that various modifications and changes can be made without departing from the scope of the present disclosure. Therefore, the consideration of the present disclosure will be illustrative rather than restrictive, and all these modifications will be included in its scope. Similarly, the advantages, other advantages and solutions to the problems of various embodiments have been described above. However, the benefits, advantages, solutions to the problems and any elements that can produce these, or make them more clear, should not be interpreted as critical, necessary or necessary. The term "include" and any other variants used in this article are all non-exclusive inclusions, so that the process, method, article or device including the list of elements not only includes these elements, but also includes other elements that are not explicitly listed or do not belong to the process, method, system, article or device. In addition, the term "coupled" and any other variants used in this article refer to physical connections, electrical connections, magnetic connections, optical connections, communication connections, functional connections and / or any other connections.

[0118] Those skilled in the art will appreciate that many changes may be made to the details of the above-described embodiments without departing from the basic principles of the invention. Therefore, the scope of the present invention should be determined solely by the claims.

Claims

1. A deflection angle detection system for a displacement actuator, characterized in that: include: A reference component, disposed on the moving part of the displacement actuator, and used to follow the moving part to move from the first position to the second position; The reference component has at least one reference surface, and a preset angle exists between the reference surface and the theoretical motion axis of the displacement actuator; A measuring device, used to measure the detection distance between the reference surface and a measuring point when the reference surface is located at the first position and the second position respectively; The processor is used to calculate the actual angle between the actual movement axis of the displacement actuator and the reference plane based on the detection distance and the movement distance between the first position and the second position, and obtain the deviation angle of the actual movement axis relative to the theoretical movement axis under the condition relative to the reference plane based on the actual angle and the preset angle.

2. The deflection angle detection system according to claim 1, wherein one of the reference surfaces of the reference component is configured as a first reflection surface, and the first reflection surface has a first preset angle with the theoretical motion axis of the displacement actuator; The measuring device is configured to be arranged at a first measuring point, the first measuring point is arranged opposite to the first reflecting surface, and is used to measure a first detection distance from the first reflecting surface to the first measuring point when the first reflecting surface is located at the first position and the second position respectively; The processor is configured to calculate the difference of the first detection distance to obtain a first deviation distance caused by the moving part moving from a first position to a second position along the actual moving axis, and calculate a first actual angle between the actual moving axis and the first reflecting surface according to the first deviation distance and the moving distance; and obtain a first deviation angle of the actual moving axis relative to the theoretical moving axis under the condition relative to the first reflecting surface according to the first actual angle and a first preset angle.

3. The deflection angle detection system according to claim 2, characterized in that: The reference component further has another reference surface configured as a second reflection surface, and a preset component angle relationship exists between the first reflection surface and the second reflection surface; the second reflection surface has a second preset angle with the theoretical motion axis; The measuring device is further configured to be arranged at a second measuring point, the second measuring point being arranged opposite to the second reflecting surface, and used to measure a second detection distance of the second reflecting surface relative to the second measuring point when the second reflecting surface is located at the first position and the second position respectively; The processor is also configured to calculate the difference in the second detection distance to obtain a second deviation distance caused by the moving part moving from the first position to the second position along the actual movement axis, and calculate a second actual angle between the actual movement axis and the second reflecting surface according to the second deviation distance and the movement spacing; and obtain a second deviation angle of the actual movement axis of the displacement actuator relative to the theoretical movement axis relative to the second reflecting surface according to the second actual angle and the second preset angle.

4. The deflection angle detection system according to claim 3, characterized in that: The first reflecting surface and the second reflecting surface are perpendicular to each other and parallel to the theoretical movement axis of the displacement actuator.

5. The deflection angle detection system according to claim 4, characterized in that: The reference component is a corner reflector having three mutually perpendicular reflection surfaces, one of which serves as a reference surface, and the other two reflection surfaces serve as the first reflection surface and the second reflection surface respectively. The reference surface is perpendicular to the theoretical motion axis of the displacement actuator.

6. The deflection angle detection system according to claim 1, characterized in that: The measuring device comprises a laser interferometer or a white light interferometer, which is used to emit a detection beam to the reference surface and receive a reflected beam generated by the reference surface, and obtain a detection distance between the reference surface and a measuring point by analyzing the reflected beam.

7. A method for detecting the deflection angle of a displacement actuator, characterized in that: include: Obtaining a movement distance of a moving part of the displacement actuator from a first position to a second position in an actual movement axis direction; wherein a reference component is provided on the moving part, and the reference component has at least one reference surface, and the reference surface has a preset angle with the theoretical movement axis direction of the displacement actuator; Acquire the detection distances of the reference surface from the measurement point when the reference surface is located at the first position and the second position respectively; Calculate the actual angle between the actual moving axis of the displacement actuator and the reference surface according to the detection distance and the moving distance; According to the actual angle and the preset angle, a deviation angle of the actual movement axis relative to the theoretical movement axis under the condition of relative to the reference surface is obtained.

8. The method for detecting an angle of deflection according to claim 7, wherein: One of the reference surfaces of the reference component is configured as a first reflection surface, and the first reflection surface has a first preset angle with respect to the theoretical motion axis of the displacement actuator; the measuring device is configured at a first measuring point to measure the distance between the first measuring point and the first reflection surface, and the first measuring point is arranged opposite to the first reflection surface; Wherein, the obtaining of the detection distances of the reference surface from the measurement point when the reference surface is located at the first position and the second position, respectively, includes: A first detection distance between the first reflecting surface and a first measuring point when the first reflecting surface is located at the first position and the second position, respectively, is measured.

9. The method for detecting an angle of deflection according to claim 8, wherein: The calculating the actual angle between the actual movement axis of the displacement actuator and the reference surface according to the detection distance and the movement interval includes: Calculating a difference in the first detection distance to obtain a first deviation distance generated when the moving part moves from the first position to the second position in the actual moving axis direction; A first actual angle between the actual movement axis and the first reflection surface is calculated according to the first deviation distance and the movement interval.

10. The method for detecting an angle of deflection according to claim 9, wherein: The step of obtaining the deviation angle of the actual movement axis relative to the theoretical movement axis under the condition of relative to the reference plane according to the actual angle and the preset angle includes: According to the first actual angle and the first preset angle, a first deviation angle of the actual movement axis relative to the theoretical movement axis under the condition of being relative to the first reflection surface is obtained.

11. The method for detecting an angle of deflection according to claim 8, wherein: The reference component further has another reference surface configured as a second reflection surface, and a preset component angle relationship exists between the first reflection surface and the second reflection surface; the second reflection surface has a second preset angle with the theoretical motion axis; the measuring device is further configured at a second measuring point to measure the distance between the second measuring point and the second reflection surface, and the second measuring point is arranged opposite to the second reflection surface; Wherein, the obtaining of the detection distances of the reference surface from the measurement point when the reference surface is located at the first position and the second position, respectively, further includes: A second detection distance relative to a second measuring point when the second reflecting surface is located at the first position and the second position is measured.

12. The method for detecting an angle of deflection according to claim 11, wherein: The calculating the actual angle between the actual movement axis of the displacement actuator and the reference surface according to the detection distance and the movement spacing also includes: Calculating a difference in the second detection distance to obtain a second deviation distance generated when the moving part moves from the first position to the second position in the actual moving axis direction; A second actual angle between the actual movement axis and the second reflection surface is calculated according to the second deviation distance and the movement interval.

13. The method for detecting an angle of deflection according to claim 12, wherein: The step of obtaining the deviation angle of the actual movement axis relative to the theoretical movement axis under the condition of relative to the reference plane according to the actual angle and the preset angle includes: According to the second actual angle and the second preset angle, a second deviation angle of the actual movement axis of the displacement actuator relative to the theoretical movement axis relative to the second reflection surface is obtained.

14. The method for detecting an angle of deflection according to claim 9, wherein: The first actual angle is calculated according to the following formula and is denoted as θx: Wherein, Dx0 is the first distance between the first measuring point and the first reflecting surface when the moving part is located at the first position; Dx1 is the second distance between the first measuring point and the first reflecting surface when the moving part is located at the second position; and L is the moving distance.

15. The method for detecting an angle of deflection according to claim 12, wherein: The second actual angle is calculated according to the following formula and is denoted as θy: Wherein, Dy0 is the third distance between the second measuring point and the second reflecting surface when the moving part is located at the first position; Dy1 is the fourth distance between the second measuring point and the second reflecting surface when the moving part is located at the second position; and L is the moving distance.

16. The method for detecting an angle of deflection according to claim 11, 12, 13 or 15, characterized in that: The first reflecting surface and the second reflecting surface are perpendicular to each other and parallel to the theoretical movement axis of the displacement actuator.

17. The method for detecting an angle of deflection according to claim 16, wherein: The reference component is a corner reflector having three mutually perpendicular reflection surfaces, one of which serves as a reference surface, and the other two reflection surfaces serve as the first reflection surface and the second reflection surface respectively. The reference surface is perpendicular to the theoretical motion axis of the displacement actuator.

18. A method for compensating the deflection angle of a displacement actuator, characterized in that: The displacement actuator has an identification direction, and the identification direction is used to identify the theoretical movement axis of the displacement actuator; The deflection compensation method include: According to the deflection angle detection method of claim 7, the deviation angle of the actual movement axis of the displacement actuator relative to the theoretical movement axis relative to the reference surface is obtained; Adjusting the position of the displacement actuator so that the marking direction is reversely deflected by the deviation angle; Alternatively, the spatial coordinate position of the moving part of the displacement actuator is corrected based on the deviation angle.

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