Angle measurement based laser feature point calibration device and method

Abstract

The application belongs to the field of laser feature point calibration, and particularly relates to a laser feature point calibration device and method based on angle measurement. The device comprises a laser emission module, a pose adjustment module, a feature point display module, a pose correction module, an angle measurement module, an image detection module and a central processing module. The feature point display module is arranged on the emission light path of the laser emission module. The output end of the pose adjustment module is connected with the feature point display module. The pose correction module is arranged on the laser emission module and the feature point display module. The angle measurement module is arranged on the side of the laser emission module and the feature point display module. The image detection module is arranged on the side of the feature point display module facing the laser emission module. The input end of the central processing module is electrically connected with the output end of the image detection module. The application can realize the calibration of laser feature points when the measured target has a slight pose change.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of laser feature point calibration, and particularly relates to a laser feature point calibration device and method based on angle measurement. BACKGROUND

[0002] Laser measurement is widely used in high-precision engineering measurement, aerospace instrument docking, astronomical observation, photoelectric tracking and large-aperture antenna pose measurement and other application scenarios due to its advantages of rapidity, dynamicity and high precision. When a high-precision machined target plate moves, the random errors of pitch, roll and azimuth angle of the target plate will occur every time the target plate moves due to the mechanical errors of the translation stage itself, which affects the precision of laser calibration or target plate pose measurement. Especially in the scene of long-distance laser transmission, a slight change in the laser emission end will cause serious errors in the final measurement precision.

[0003] Most of the existing researches use camera calibration and machine vision methods to match the spatial coordinate points at different positions, such as Chinese patent CN110030926B. However, such methods cannot match when the measured target has a slight pose change due to small errors and high precision, and the laser calibration and measurement precision is lower than the angle measurement precision of the theodolite. Moreover, the existing methods only correct the pose of the measured target, and there is no related research on the correction of other laser spots on the measured target. SUMMARY

[0004] The purpose of the present application is to solve the technical problem that the existing technology cannot match when the measured target has a slight pose change due to small errors and high precision, and the laser calibration and measurement precision is lower than the angle measurement precision of the theodolite, and to provide a laser feature point calibration device and method based on angle measurement.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows:

[0006] A laser feature point calibration device based on angle measurement, characterized in that:

[0007] The device comprises a laser emission module, a pose adjustment module, a feature point display module, a pose correction module, an angle measurement module, an image detection module and a central processing module.

[0008] The laser emission module is used for laser emission.

[0009] The feature point display module is arranged on the emission light path of the laser emission module, and the display surface thereof intersects with the laser emitted by the laser emission module to form a laser spot.

[0010] The output end of the pose adjustment module is connected with the feature point display module, and is used for adjusting the pose of the feature point display module.

[0011] The pose correction module comprises a first correction unit and a second correction unit, and the first correction unit and the second correction unit are arranged on the laser emission module and the feature point display module respectively.

[0012] The angle measurement module comprises a first angle measurement unit and a second angle measurement unit; the first angle measurement unit and the second angle measurement unit are arranged on the side of the laser emission module and the feature point display module respectively; the first angle measurement unit is used to collimate the laser emission module and the feature point display module by correcting the first correction unit and the second correction unit; and the second angle measurement unit is used to obtain the multi-dimensional angle of the feature point display module.

[0013] The image detection module is arranged on the side of the feature point display module facing the laser emission module, and the field of view range of the image detection module can at least cover the region where the laser spot is located on the feature point display module, and the image detection module is used to obtain a two-dimensional image containing the laser spot under different poses.

[0014] The input end of the central processing module is electrically connected to the output end of the image detection module, and the central processing module is used to obtain the center position of the rotation axis of the feature point display module according to the two-dimensional image containing the laser spot under different poses and the multi-dimensional angle of the feature point display module obtained by the second angle measurement unit, and obtain the coordinates of the laser spot on the display surface space coordinate system of the feature point display module after the pose adjustment at the next moment according to the center position of the rotation axis, so as to realize the calibration of the laser feature point.

[0015] Further, the central processing module can also be used to correct the displacement of the laser translation direction according to the coordinates of the laser spot and the translation error of the pose adjustment module calibrated in advance.

[0016] Further, the laser emitted by the laser emission module is M parallel lasers with respect to the perpendicular line of the display surface of the feature point display module, and M is greater than or equal to 1.

[0017] The central processing module is also used to correct the pose of the feature point display module and other laser beams with any angle incident on the feature point display module according to the multi-dimensional angle of the feature point display module measured by the second angle measurement unit and the M parallel lasers with respect to the perpendicular line of the display surface emitted by the laser emission module.

[0018] Further, the pose adjustment module comprises a translation adjustment unit and a rotation adjustment unit.

[0019] The translation movement track of the translation adjustment unit is parallel to at least one laser beam emitted by the laser emission module.

[0020] The mounting end of the translation adjustment unit is mounted on the output end of the rotation adjustment unit, and the feature point display module is mounted on the output end of the translation adjustment unit.

[0021] Further, the translation adjustment unit is a conveyor belt mechanism or a conveyor shaft mechanism, and the rotation adjustment unit is a rotation shaft mechanism.

[0022] Further, the first correction unit and the second correction unit are both reference mirrors, and the image detection module is a camera.

[0023] Further, the feature point display module is a rectangular target surface.

[0024] The long side of the target surface is defined as the x-axis, the short side is defined as the y-axis, and the direction perpendicular to the target surface is defined as the z-axis.

[0025] The first angle measurement unit comprises one theodolite, and the second angle measurement unit comprises three theodolites.

[0026] The three theodolites in the second angle measurement unit are arranged in the x-axis, y-axis and z-axis directions of the target surface, and are used to obtain the multi-dimensional angle of the pose adjustment module.

[0027] Meanwhile, the application also provides a laser feature point calibration method based on angle measurement, which adopts the laser feature point calibration device based on angle measurement.

[0028] Step 1: adjust the position of the first angle measurement unit, and calibrate the first angle measurement unit through the first correction unit.

[0029] Step 2: emit laser light to the feature point display module through the laser emission module, and form a laser spot on the display surface thereof.

[0030] Step 3: collimate the second correction unit through the first angle measurement unit, and then adjust the pose of the feature point display module through the pose adjustment module, so as to realize the collimation of the laser emission module and the feature point display module.

[0031] Step 4: continue to adjust the pose of the feature point display module through the pose adjustment module, in the process, obtain the two-dimensional image containing the laser spot under different poses through the image detection module, and obtain the multi-dimensional angle of the feature point display module under different poses through the second angle measurement unit.

[0032] Step 5: obtain the rotation shaft center position of the feature point display module according to the two-dimensional image containing the laser spot under different poses and the angle of the feature point display module under different poses through the central processing module, and then obtain the coordinates of the laser spot based on the display surface space coordinate system of the feature point display module after the pose adjustment at the next moment, so as to realize the calibration of the laser feature point.

[0033] Further, in step 2, the laser emitted by the laser emission module is one parallel to the perpendicular line of the display surface of the feature point display module.

[0034] In the initial state, the coordinates of a laser spot on the display surface of the feature point display module are defined as follows: After adjustment, the coordinates of the laser spot at any pose are: The angle generated by the feature point display module rotating around the x-axis is the pitch angle β, the angle generated around the y-axis is the azimuth angle α, and the angle generated around the z-axis is the roll angle. When the pose adjustment module adjusts the pose of the feature point display module, the pitch angle β, azimuth angle α, and / or roll angle are adjusted. The location is the center position of the rotation axis, P(m, n, p);

[0035] In step 5, when the included angle is the roll angle At that time, the coordinate point p in the rotation axis center position P(m, n, p) is always 0, and the coordinate points m and n are calculated using the following formula:

[0036] ;

[0037] When the included angle is the pitch angle β, the coordinate point n in the rotation axis center position P(m, n, p) is always 0, and the coordinate points m and p are... The following formula is used for calculation:

[0038] ;

[0039] When the included angle is azimuth angle α, the coordinate point m in the rotation axis center position P(m, n, p) is always 0, and the coordinate point... and The following formula is used for calculation:

[0040] ;

[0041] When the included angle is composed of pitch angle β, azimuth angle α, and roll angle When assembled, the coordinates of point m in the rotation axis center position P(m, n, p) are... and The following formula is used for calculation:

[0042] .

[0043] Furthermore, in step 2, the laser emitted by the laser emitting module consists of three laser beams, all of which are parallel to the perpendicular line of the display surface of the feature point display module.

[0044] When the pose adjustment module adjusts the pose of the feature point display module, the included angle generated by the rotation of the feature point display module around the z-axis is defined as the roll angle. Roll angle The position is the rotation axis center position P (m, n, p); the coordinate point p in the rotation axis center position P (m, n, p) is always 0, and the two-dimensional coordinates of the three laser spots on the display surface of the feature point display module in the initial state are respectively: 、 、 , the two-dimensional coordinates under any posture after adjustment are respectively: 、 、 ;

[0045] In step 5, the coordinate points m and n in the rotation axis center position P (m, n, p) are calculated by the following formula:

[0046]

[0047] ; .

[0048] The beneficial effects of the present application are:

[0049] 1. The present application realizes high-precision calibration of laser feature points according to the rotation axis center position of the feature point display module by real-time monitoring of the multi-dimensional angle of the feature point display module through a high-precision angle measuring module, combining the two-dimensional image containing laser spots under different postures, and obtaining the rotation axis center position of the feature point display module.

[0050] 2. The present application can realize high-precision measurement of small angles of the feature point display module, and can also realize large-angle measurement in industrial posture measurement. When the feature point display module undergoes a small change in posture and high-precision measurement is required, one parallel laser and an angle measuring module can achieve this requirement. When the feature point display module undergoes a large change in posture or is far away from the laser emitting module, the angle measuring module cannot rotate a large angle for measurement, and three parallel lasers can be used for measurement.

[0051] 3. The present application solves the rotation axis center position of the laser spot under different postures of the feature point display module through space vector conversion, simplifies the calculation process, reduces the complexity of algorithm dimension, and has a unified operation rule, which is convenient for the construction and deduction of the mathematical model of the rotation axis center position, and avoids the error caused by complex algorithms.

[0052] 4. The laser vector method used in the present application has low cost and can adapt to different working conditions indoors and outdoors, different measurement requirements of large and small angles, distance measurement, etc., and can also be used in various implementation scenarios such as conveyor object grabbing, large and small object posture monitoring, etc., which widens the implementability and universality.

[0053] 5、The present application only adjusts the pose of the feature point display module to calibrate parallel laser, and the laser emission module remains stable, so that the influence factors of unstable laser caused by adjustment of the laser emission module can be avoided, a stable emission environment for long-distance laser transmission is provided, and the error influence in high-precision measurement process is reduced.

[0054] 6、The present application adjusts the parallel laser and the feature point display module to be perpendicular to each other, so as to reduce the pose correction error caused by any angle error as much as possible.

[0055] 7、The present application can reach an angle second level of measurement accuracy when measuring the slight pose change of the feature point display module, and the measurement accuracy is high.

[0056] 8、The present application collimates the feature point display module, and only needs to read the angle change of the theodolite after the pose change of the feature point display module, so that the implementation steps are simplified, the implementation time is saved, and the implementation accuracy is ensured.

[0057] 9、The present application solves the center position of the rotation axis under each pose by using the two-dimensional image containing the laser spot of the multiple parallel lasers when the pose of the feature point display module changes, a new method of laser feature point calibration is realized, and the inherent error caused by angle laser is solved from the emission end of the laser.

[0058] 10、The present application uses parallel laser as a basic research method of laser feature point calibration, can provide accurate data basis for subsequent any angle laser correction, has strong universality, and has wide application range. BRIEF DESCRIPTION OF DRAWINGS

[0059] Figure 1 is a structural schematic diagram of an embodiment of a laser feature point calibration device based on angle measurement of the present application;

[0060] Figure 2 is a partial enlarged schematic diagram of Figure 1 ;

[0061] Figure 3 is a schematic diagram of the initial position of the feature point display module at t0 moment and the position after translation without pose change at ti moment in the embodiment of the present application, and the direction indicated by the arrow in the figure is the translation direction;

[0062] Figure 4 is a schematic diagram of the initial position of the feature point display module at t0 moment and the position after rotation around the x axis at ti moment in the embodiment of the present application, and the direction indicated by the arrow in the figure is the rotation direction around the x axis;

[0063] Figure 5 is a schematic diagram of the initial position of the feature point display module at t0 moment and the position after rotation around the y axis at ti moment in the embodiment of the present application, and the direction indicated by the arrow in the figure is the rotation direction around the y axis;

[0064] Figure 6 is the initial position of the feature point display module at time t0 and the position after rotating around the z-axis at time ti in the embodiment of the present application, and the direction indicated by the arrow in the figure is the rotating direction around the z-axis;

[0065] Figure 7 is the initial position of the feature point display module at time t0 and the position after rotating around the x, y and z axes at time ti in the embodiment of the present application, and the direction indicated by the arrow in the figure is the rotating direction around the x, y and z axes.

[0066] In the figure: 1-laser emitting module, 2-pose adjusting module, 21-translation adjusting unit, 22-rotation adjusting unit; 3-feature point display module, 4-pose correcting module, 41-first correcting unit, 42-second correcting unit; 5-angle measuring module, 51-first angle measuring unit, 52-second angle measuring unit, 6-image detecting module. DETAILED DESCRIPTION

[0067] In order to make the object, advantages and features of the present application clearer, the following will make further detailed description of the laser feature point calibration device and method based on angle measurement according to the accompanying drawings and specific embodiments. The advantages and features of the present application will be clearer according to the following specific embodiments.

[0068] Reference Figure 1 , the device for laser feature point calibration based on angle measurement in the embodiment mainly comprises a laser emitting module 1, a pose adjusting module 2, a feature point display module 3, a pose correcting module 4, an angle measuring module 5, an image detecting module 6 and a central processing module.

[0069] Among them, the centers of the laser emitting module 1, the feature point display module 3 and the pose adjusting module 2 are in the same plane. The laser emitting module 1 comprises a laser, a laser sleeve and corresponding adjusting and fixing screws. With the normal line of the display surface of the feature point display module 3 as the reference, according to different calibration requirements, the laser emitted by the laser emitting module 1 is M beams of lasers parallel to the normal line of the display surface, M≥1.

[0070] The feature point display module 3 is specifically a rectangular target surface, and the feature point display module 3 is arranged on the emitting light path of the laser emitting module 1, and the display surface thereof intersects with the laser emitted by the laser emitting module 1 to form a laser spot. A space coordinate system is set at the initial position of the feature point display module 3, and in the embodiment, the long side of the feature point display module 3 is taken as the x-axis, the short side is taken as the y-axis, and the direction perpendicular to the target surface is taken as the z-axis, and the space coordinate system conforms to the right-hand rule. In other embodiments of the present application, the space coordinate system can be defined as any direction in the target space, as long as the right-hand rule is met.

[0071] The pose adjustment module 2 comprises a translation adjustment unit 21 and a rotation adjustment unit 22; the translation adjustment unit 21 is a conveyor belt mechanism or a transmission shaft mechanism, etc., which can realize translational motion only. The rotation adjustment unit 22 is a rotating shaft mechanism, etc., which can realize rotational motion only. The translational motion trajectory of the translation adjustment unit 21 is parallel to at least one laser emitted by the laser emitting module 1; the mounting end of the translation adjustment unit 21 is mounted on the output end of the rotation adjustment unit 22, and the feature point display module 3 is mounted on the output end of the translation adjustment unit 21; through the mutual coordination of the translation adjustment unit 21 and the rotation adjustment unit 22, the translational and rotational poses of the feature point display module 3 can be adjusted.

[0072] The pose correction module 4 comprises a first correction unit 41 and a second correction unit 42, specifically, the first correction unit 41 and the second correction unit 42 are both reference mirrors, and the first correction unit 41 and the second correction unit 42 are respectively arranged on the laser emitting module 1 and the feature point display module 3. The angle measuring module 5 comprises a first angle measuring unit 51 and a second angle measuring unit 52, specifically, the first angle measuring unit 51 comprises a theodolite, and the first angle measuring unit 51 is arranged on the side of the laser emitting module 1, so as to correct the first correction unit 41 and the second correction unit 42 through the first angle measuring unit 51, so as to collimate the laser emitting module 1 and the feature point display module 3. The second angle measuring unit 52 comprises three theodolites, and the three theodolites are respectively arranged on the x-axis, y-axis and z-axis directions of the feature point display module 3, so as to obtain the multi-dimensional angle of the feature point display module 3.

[0073] The image detection module 6 is a camera, and the image detection module 6 is arranged on the side of the feature point display module 3 facing the laser emitting module 1, and the field of view range of the image detection module 6 can at least cover the area where the laser spot on the feature point display module 3 is located, so as to obtain the two-dimensional image containing the laser spot under different poses.

[0074] The input end of the central processing module is electrically connected with the output end of the image detection module 6, and according to the two-dimensional image containing the laser spot under different poses and the multi-dimensional angle of the feature point display module 3 obtained by the second angle measuring unit 52, the rotational axis center position of the feature point display module 3 is obtained, and then the two-dimensional coordinates of the laser spot based on the feature point display module 3 display surface space coordinate system after the pose adjustment at the next moment are obtained according to the rotational axis center position, so as to realize the laser feature point calibration.

[0075] When the pose of the measured target changes very slightly, the specific implementation steps are as follows:

[0076] Step 1, adjust the position of the first angle measuring unit 51, and calibrate the first angle measuring unit 51 through the reference mirror placed on the laser emitting module 1.

[0077] Step 2, a laser beam is emitted by the laser emitting module 1, which has been adjusted to be parallel to the perpendicular line of the display surface of the feature point display module 3, so as to intersect with the display surface of the feature point display module 3 and form a laser spot.

[0078] Step 3, the pose of the feature point display module 3 is adjusted by the pose adjustment module 2, and the collimation of the laser emitting module 1 and the feature point display module 3 is realized by collimating the reference mirror placed on the feature point display module 3 through the first angle measuring unit 51.

[0079] Step 4, the pose of the feature point display module 3 is continuously adjusted by the pose adjustment module 2, and in this process, the two-dimensional images containing the laser spot under different poses are obtained by the image detection module 6, and the multi-dimensional angles of the feature point display module 3 under different poses are obtained by the second angle measuring unit 52, that is, the roll angle, pitch angle and azimuth angle of the feature point display module 3 are read and recorded.

[0080] Step 5, the central processing module obtains the position of the rotation axis center of the feature point display module 3 according to the two-dimensional images containing the laser spot under different poses and the multi-dimensional angles of the feature point display module 3 under different poses, and then obtains the coordinates of the laser spot based on the spatial coordinate system of the display surface of the feature point display module 3 after the pose adjustment at the next moment, so as to realize the laser feature point calibration.

[0081] The angle between the feature point display module 3 in the initial state and the rotation around the x-axis is defined as the pitch angle β, the angle between the rotation around the y-axis is defined as the azimuth angle α, and the angle between the rotation around the z-axis is defined as the roll angle ; see Figure 2 , when the pose adjustment module 2 adjusts the pose of the feature point display module 3, the positions of the pitch angle β, the azimuth angle α and the roll angle are the rotation axis center position P (m, n, p).

[0082] The laser spot A before and after the adjustment of the pose adjustment module 2 can be represented by a spatial vector:

[0083] ;

[0084] After adjustment, the laser spot A is obtained , the coordinates of the laser spot A before the adjustment of the pose adjustment module 2 are: , and the coordinates of the laser spot A after the adjustment are: .

[0085] and can be represented as:

[0086] ;

[0087] and The rotation matrix between them can be expressed as:

[0088] ;

[0089] ;

[0090] ;

[0091] Since the error caused by the pose adjustment module 2 is small, the three rotation matrices can be approximately written as follows:

[0092] ;

[0093] ;

[0094] ;

[0095] , , are the roll rotation matrix, pitch rotation matrix and azimuth rotation matrix respectively. Referring to Figure 7 , the position coordinate relationship formula of the laser spot A before and after the adjustment of the feature point display module 3 rotating around the x-axis, y-axis and z-axis can be expressed as:

[0096] ;

[0097] Referring to Figure 4 , taking the pitch angle for example, the position coordinate relationship formula of 1 laser before and after the adjustment of the laser spot A can be obtained:

[0098] ;

[0099] Referring to Figure 5 , taking the azimuth angle for example, the position coordinate relationship formula of 1 laser before and after the adjustment of the laser spot A can be obtained:

[0100] ;

[0101] Referring to Figure 6 , taking the roll angle for example, the position coordinate relationship formula of 1 laser before and after the adjustment of the laser spot A can be obtained:

[0102] ;

[0103] Referring to Figure 3The pose adjustment includes position adjustment and attitude adjustment, all the pose adjustments can be regarded as first position adjustment and then attitude adjustment, when the included angle is the roll angle , the rotation axis center position P(m, n, p) is for the attitude adjustment after the position adjustment, and the position adjustment is for the z-axis position movement, it can be known that , the following formula is obtained , and it can be known that the coordinate point p in the rotation axis center position P(m, n, p) is always 0, so it is omitted in the subsequent calculation.

[0104] By substituting the above formula, the following formula can be obtained:

[0105] ;

[0106] Based on the above formula, the position coordinate formula of the rotation axis center position P(m, n, p) can be obtained:

[0107] ;

[0108] Similarly, the position coordinate formula of the rotation axis position P based on other different adjustment angles can be obtained by using the above method:

[0109] When the included angle is the pitch angle β, the coordinate point n in the rotation axis center position P(m, n, p) is always 0, and the coordinate points m and are calculated by using the following formula:

[0110] ;

[0111] When the included angle is the azimuth angle α, the coordinate point m in the rotation axis center position P(m, n, p) is always 0, and the coordinate points n and are calculated by using the following formula:

[0112] .

[0113] The specific implementation steps when the measured target pose changes greatly are different from the specific implementation steps when the measured target pose changes extremely slightly, and the steps 2 and 5 are different, and the remaining steps are the same.

[0114] Step 2, the laser emitted by the laser emission module 1 is 3 lasers which are parallel to the perpendicular of the display surface of the feature point display module 3, the 3 lasers intersect with the display surface of the feature point display module 3 to form 3 laser spots.

[0115] The rotation axis center position in step 5 is calculated by using the following method:

[0116] It is defined that the two-dimensional coordinates of the 3 laser spots on the display surface of the feature point display module 3 in the initial state are respectively:​ 、 、 , the two-dimensional coordinates of any pose after adjustment are respectively: 、 、 ;

[0117] When the feature point display module 3 rotates around the z-axis to produce a roll angle , the coordinate p in the rotation axis center position P (m, n, p) is always 0, and the coordinates m and n are calculated using the following formula:

[0118] ;

[0119] Definition: , ;

[0120] The above formula can be converted to:

[0121] ;

[0122]

[0123] According to the rotation axis center position, the coordinates of the laser spot based on the feature point display module 3 display surface space coordinate system after pose adjustment at the next time can be obtained.

[0124] At the same time, on the basis of the original laser spot coordinates, the translation error of the pose adjustment module 2 pre-calibrated can be added to correct the displacement in the laser translation direction. Moreover, according to the multi-dimensional angle of the feature point display module 3 measured by the second angle measuring unit 52 and the three parallel lasers, the pose of the feature point display module 3 can be corrected, and other arbitrary angle lasers incident on the display surface of the feature point display module 3 can also be corrected.

Claims

1. A laser feature point calibration device based on angle measurement, characterized in that: it comprises a laser emitting module (1), a pose adjustment module (2), a feature point display module (3), a pose correction module (4), an angle measurement module (5), an image detection module (6) and a central processing module; the laser emitting module (1) is used for laser emission; the feature point display module (3) is arranged on the light path of the laser emitting module (1), and the display surface thereof intersects with the laser emitted by the laser emitting module (1) to form a laser spot; the output end of the pose adjustment module (2) is connected with the feature point display module (3), and the pose adjustment module (2) is used for adjusting the pose of the feature point display module (3); the pose correction module (4) comprises a first correction unit (41) and a second correction unit (42), and the first correction unit (41) and the second correction unit (42) are arranged on the laser emitting module (1) and the feature point display module (3) respectively; the angle measurement module (5) comprises a first angle measurement unit (51) and a second angle measurement unit (52), and the first angle measurement unit (51) and the second angle measurement unit (52) are arranged on the side of the laser emitting module (1) and the feature point display module (3) respectively; the first angle measurement unit (51) is used for collimating the laser emitting module (1) and the feature point display module (3) by correcting the first correction unit (41) and the second correction unit (42); and the second angle measurement unit (52) is used for obtaining the multi-dimensional angle of the feature point display module (3); the image detection module (6) is arranged on the side of the feature point display module (3) facing the laser emitting module (1), and the field of view range of the image detection module (6) can at least cover the region where the laser spot on the feature point display module (3) is located, and the image detection module (6) is used for obtaining a two-dimensional image containing the laser spot under different poses; the input end of the central processing module is electrically connected with the output end of the image detection module (6), and the central processing module is used for obtaining the center position of the rotation axis of the feature point display module (3) according to the two-dimensional image containing the laser spot under different poses and the multi-dimensional angle of the feature point display module (3) obtained by the second angle measurement unit (52), and obtaining the coordinates of the laser spot on the display surface space coordinate system of the feature point display module (3) after the pose adjustment at the next moment according to the center position of the rotation axis, so as to realize the calibration of the laser feature point. 2.The laser feature point calibration device based on angle measurement according to claim 1, characterized in that: the central processing module is further used for realizing the displacement correction of the laser translation direction according to the coordinates of the laser spot and the translation error of the pose adjustment module (2) calibrated in advance. 3.The laser feature point calibration device based on angle measurement according to claim 1 or 2, characterized in that: with the perpendicular of the display surface of the feature point display module (3) as the reference, the laser emitted by the laser emitting module (1) is M parallel lasers perpendicular to the display surface, and M≥1. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The central processing module is further configured to correct the pose of the feature point display module (3) according to the multi-dimensional angle of the feature point display module (3) measured by the second angle measuring unit (52) and the laser emitted by the laser emitting module (1) which is parallel to the normal line of the display surface of the feature point display module (3), and other arbitrary angle laser incident to the display surface of the feature point display module (3).

4. The laser feature point calibration device based on angle measurement according to claim 3, characterized in that: The pose adjustment module (2) comprises a translation adjustment unit (21) and a rotation adjustment unit (22); The translation movement track of the translation adjustment unit (21) is parallel to at least one laser emitted by the laser emitting module (1); The mounting end of the translation adjustment unit (21) is mounted on the output end of the rotation adjustment unit (22), and the feature point display module (3) is mounted on the output end of the translation adjustment unit (21).

5. The laser feature point calibration device based on angle measurement according to claim 4, characterized in that: The translation adjustment unit (21) is a conveyor belt mechanism or a transmission shaft mechanism, and the rotation adjustment unit (22) is a rotating shaft mechanism.

6. The laser feature point calibration device based on angle measurement according to claim 1, characterized in that: The first correction unit (41) and the second correction unit (42) are both reference mirrors, and the image detection module (6) is a camera.

7. The laser feature point calibration device based on angle measurement according to claim 1, characterized in that: The feature point display module (3) is a rectangular target surface; The long side of the target surface is defined as the x-axis, the short side is defined as the y-axis, and the direction perpendicular to the target surface is defined as the z-axis; The first angle measuring unit (51) comprises one theodolite, and the second angle measuring unit (52) comprises three theodolites; The three theodolites in the second angle measuring unit (52) are arranged in the x-axis, y-axis and z-axis directions of the target surface.

8. A laser feature point calibration method based on angle measurement, using the laser feature point calibration device based on angle measurement according to any one of claims 1-7, characterized in that, The method comprises the following steps: Step 1, adjusting the position of the first angle measuring unit (51) and calibrating the first angle measuring unit (51) through the first correction unit (41); Step 2, emitting laser to the feature point display module (3) through the laser emitting module (1) to form a laser spot on the display surface thereof; Step 3, collimating the second correction unit (42) through the first angle measuring unit (51), and then adjusting the pose of the feature point display module (3) through the pose adjustment module (2) to realize the collimation of the laser emitting module (1) and the feature point display module (3); Step 4, continuously adjusting the pose of the feature point display module (3) through the pose adjustment module (2), in the process, acquiring two-dimensional images containing the laser spot under different poses through the image detection module (6), and acquiring the multi-dimensional angle of the feature point display module (3) under different poses through the second angle measuring unit (52). Step 5, the central processing module obtains the position of the rotation axis center of the feature point display module (3) according to the two-dimensional images containing the laser spots in different poses and the multi-dimensional angles of the feature point display module (3) in different poses, and then obtains the coordinates of the laser spots based on the feature point display module (3) in the spatial coordinate system of the display surface of the feature point display module (3) after the pose adjustment at the next moment, so as to realize the calibration of the laser feature points.

9. The laser feature point calibration method based on angle measurement according to claim 8, characterized in that: In step 2, the laser emitted by the laser emission module (1) is one laser parallel to the perpendicular of the display surface of the feature point display module (3); The coordinate of a laser spot on the display surface of the defined feature point display module (3) in the initial state is: , the coordinate of the laser spot after adjustment in any pose is: ; the included angle generated by the rotation of the feature point display module (3) around the x-axis is the pitch angle β, the included angle generated by the rotation around the y-axis is the azimuth angle α, and the included angle generated by the rotation around the z-axis is the roll angle ; when the pose adjustment module (2) adjusts the pose of the feature point display module (3), the positions of the pitch angle β, the azimuth angle α and / or the roll angle are the rotation axis center positions P(m, n, p). In Step 5, when the included angle is the roll angle the coordinate point p in the center position P (m, n, p) of the rotation axis is always 0, and the coordinate points m and n are calculated using the following equations: ； When the included angle is the pitch angle β, the coordinate point n in the center position P (m, n, p) of the rotation axis is always 0, and the coordinate points m and p are calculated by the following formula: The following formula is used for calculation: ； When the included angle is the azimuth angle a, the coordinate point m in the center position P (m, n, p) of the rotation axis is always 0, and the coordinate point n is and The following formula is used for calculation: ； When the included angle is composed of the pitch angle β, the azimuth angle α, and the roll angle The coordinate point m in the center position P (m, n, p) of the rotation axis, and is calculated by using the following formula: 。 10. The laser feature point calibration method based on angle measurement according to claim 8, characterized in that: In step 2, the laser emitted by the laser emission module (1) is three lasers parallel to the perpendicular of the display surface of the feature point display module (3); When the pose adjustment module (2) adjusts the pose of the feature point display module (3), the included angle generated by the rotation of the feature point display module (3) around the z-axis is a roll angle , the position of the roll angle is a rotation axis center position P (m, n, p); the coordinate point p in the rotation axis center position P (m, n, p) is always 0, and the two-dimensional coordinates of the three laser spots on the display surface of the feature point display module (3) in the initial state are respectively: 、 、 , and the two-dimensional coordinates in any adjusted pose are respectively: 、 、 ; In step 5, the coordinate points m and n in the position P (m, n, p) of the rotation axis center are calculated by using the following formula: ； ； 。

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