Laser feature point calibration device and method based on angle measurement

Abstract

The invention 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 an emission light path of the laser emission module; the output end of the pose adjusting 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 peripheral sides of the laser emission module and the feature point display module; the image detection module is arranged on one side, facing the laser emission module, of the feature point display module; the input end of the central processing module is electrically connected with the output end of the image detection module. According to the invention, the calibration of the laser feature points can be realized when the measured target has small pose change.

Description

Technical Field

[0001] This invention belongs to the field of laser feature point calibration, specifically relating to a laser feature point calibration device and method based on angle measurement. Background Technology

[0002] Laser measurement, due to its advantages of speed, dynamism, and high precision, is widely used in various applications such as high-precision engineering measurement, aerospace instrument docking, astronomical observation, photoelectric tracking, and large-aperture antenna attitude measurement. However, during the movement of a high-precision machined target plate, the mechanical errors of the translation stage itself cause random angular errors in pitch, roll, and azimuth with each movement. This affects the accuracy of laser calibration or target plate attitude measurement, especially in long-distance laser transmission scenarios where even minute changes at the laser emitter can lead to significant errors in the final measurement accuracy.

[0003] Existing research mostly employs camera calibration and machine vision methods for matching spatial coordinate points at different locations, such as Chinese patent CN110030926B. However, these methods cannot match targets with slight pose changes due to their small errors and high precision. Furthermore, their laser calibration and measurement accuracy is lower than that of theodolites. Moreover, existing methods only address the pose correction of the target and lack research on the correction of other laser spots on the target. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problem that existing technologies cannot match the accuracy of laser calibration and measurement when the measured target undergoes slight pose changes due to small errors and high precision, resulting in lower accuracy than the angle measurement accuracy of theodolites. The invention provides a laser feature point calibration device and method based on angle measurement.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A laser feature point calibration device based on angle measurement, characterized by: It includes 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 laser emitting module is used for laser emission; The feature point display module is set in the emission optical path of the laser emission module, and its display surface intersects with the laser emitted by the laser emission module to form a laser spot; The output of the pose adjustment module is connected to the feature point display module and is used to adjust the pose of the feature point display module. The pose correction module includes a first correction unit and a second correction unit, which are respectively disposed on the laser emission module and the feature point display module. The angle measurement module includes a first angle measurement unit and a second angle measurement unit; the first angle measurement unit and the second angle measurement unit are respectively disposed on the periphery of the laser emission module and the feature point display module; 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; the second angle measurement unit is used to obtain the multi-dimensional angles of the feature point display module; The image detection module is located on the side of the feature point display module facing the laser emission module. Its field of view can at least cover the area where the laser spot is located on the feature point display module, and is used to acquire two-dimensional images containing the laser spot under different poses. The input end of the central processing module is electrically connected to the output end of the image detection module. It is used to obtain the rotation axis center position of the feature point display module based on 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 measuring unit. Then, based on the rotation axis center position, it obtains the coordinates of the laser spot after pose adjustment based on the spatial coordinate system of the display surface of the feature point display module, so as to realize the calibration of the laser feature points.

[0006] Furthermore, the central processing module can also be used to correct the displacement in the laser translation direction based on the coordinates of the laser spot and the translation error of the pre-calibrated pose adjustment module.

[0007] Furthermore, taking the vertical line of the display surface of the feature point display module as a reference, the laser emitted by the laser emission module is M laser beams parallel to the vertical line of the display surface, where M≥1; The central processing module is also used to correct the pose of the feature point display module based on the multidimensional angles of the feature point display module measured by the second angle measuring unit and the M-beams of laser emitted by the laser emitting module that are parallel to the vertical line of the display surface, as well as other arbitrary angle lasers incident on the feature point display module.

[0008] Furthermore, the pose adjustment module includes a translation adjustment unit and a rotation adjustment unit; The translational trajectory of the translation adjustment unit is parallel to at least one laser beam emitted by the laser emission module; The mounting end of the translation adjustment unit is installed at the output end of the rotation adjustment unit, and the feature point display module is installed at the output end of the translation adjustment unit.

[0009] Furthermore, the translation adjustment unit is a conveyor belt mechanism or a conveyor shaft mechanism, and the rotation adjustment unit is a rotation shaft mechanism.

[0010] Furthermore, both the first and second correction units are reference mirrors, and the image detection module is a camera.

[0011] Furthermore, the feature point display module is a rectangular target surface; Define the longer side of the target surface as the x-axis, the shorter side as the y-axis, and the direction perpendicular to the target surface as the z-axis; The first angle measuring unit includes one theodolite, and the second angle measuring unit includes three theodolites; The three theodolites in the second angle measuring unit are respectively set in the x-axis, y-axis and z-axis directions of the target surface to obtain the multi-dimensional angles of the pose adjustment module.

[0012] Meanwhile, the present invention also provides a laser feature point calibration method based on angle measurement, which uses the aforementioned laser feature point calibration device based on angle measurement, and is characterized by including the following steps: Step 1: Adjust the position of the first angle measuring unit and calibrate the first angle measuring unit using the first calibration unit; Step 2: The laser is emitted from the laser emitting module to the feature point display module, forming a laser spot on its display surface; Step 3: The first angle measuring unit collimates the second correction unit, and then the pose adjustment module adjusts the pose of the feature point display module to achieve collimation between the laser emission module and the feature point display module. Step 4: Continue to adjust the pose of the feature point display module through the pose adjustment module. During this process, the image detection module acquires two-dimensional images containing laser spots under different poses, and the second angle measurement unit acquires the multi-dimensional angles of the feature point display module under different poses. Step 5: The central processing module obtains the rotation axis center position of the feature point display module based on the two-dimensional image containing the laser spot under different poses and the angle of the feature point display module under different poses. Then, based on the rotation axis center position, the coordinates of the laser spot after pose adjustment based on the spatial coordinate system of the display surface of the feature point display module are obtained, thereby realizing the calibration of the laser feature points.

[0013] Furthermore, in step 2, the laser emitted by the laser emitting module is a laser beam parallel to the perpendicular line of the display surface of the feature point display module; 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); 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: ; 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: ; 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: ; 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: .

[0014] 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. 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 location is the center position of the rotation axis, P(m, n, p); the coordinate point p in the center position of the rotation axis, P(m, n, p), is always 0. In the initial state, the two-dimensional coordinates of the three laser spots on the display surface of the feature point display module are as follows: , , After adjustment, the two-dimensional coordinates in any pose are as follows: , , ; In step 5, the coordinates of points m and n in the center position P(m, n, p) of the rotation axis are calculated using the following formula:

[0015] ; .

[0016] The beneficial effects of this invention are: 1. This invention uses a high-precision angle measurement module to monitor the multi-dimensional angles of the feature point display module in real time. Combined with two-dimensional images containing laser spots under different poses, the rotation axis center position of the feature point display module is obtained. Based on the rotation axis center position, high-precision calibration of laser feature points is achieved, thereby realizing laser feature point calibration when the target under test undergoes a small pose change.

[0017] 2. This invention can achieve high-precision measurement of small angles using the feature point display module, and also large-angle measurement in industrial pose measurement. When the feature point display module undergoes minor pose changes and requires high-precision measurement, a combination of a single parallel laser beam and an angle measuring module can meet this requirement. When the feature point display module undergoes large-angle pose changes or is far from the laser emitting module, and the angle measuring module cannot rotate a large angle for measurement, measurement can be achieved using three parallel laser beams.

[0018] 3. This invention solves the rotation axis center position of the laser spot in different poses of the feature point display module by transforming spatial vectors, which simplifies the calculation process, reduces the complexity of the algorithm dimension, and has unified operation rules, which facilitates the construction and derivation of mathematical models about the rotation axis center position and avoids the errors caused by complex algorithms themselves.

[0019] 4. The laser vector method used in this invention is low in cost and can adapt to different indoor and outdoor working conditions, different measurement needs of different sizes and angles, and measurement at different distances. It can also be used in a variety of implementation scenarios, such as conveyor belt object grasping and position and pose monitoring of objects of different sizes, thus broadening its feasibility and versatility.

[0020] 5. This invention calibrates the parallel laser by adjusting the pose of the feature point display module, while keeping the laser emission module stable. This avoids the instability caused by adjusting the laser emission module and provides a stable emission environment for long-distance laser transmission, reducing the impact of errors in the high-precision measurement process.

[0021] 6. This invention minimizes pose correction errors caused by any other angular errors by adjusting the parallel laser to be perpendicular to the feature point display module.

[0022] 7. When measuring minute pose changes of the feature point display module, the present invention can achieve a measurement accuracy at the arcsecond level, which is highly accurate.

[0023] 8. By aligning the feature point display module, this invention simplifies the implementation steps, saves implementation time, and ensures implementation accuracy after the feature point display module changes its pose by simply reading the angle change of the theodolite.

[0024] 9. This invention solves the rotation axis center position under each pose by using a two-dimensional image containing laser spots from multiple parallel laser beams when the pose of the feature point display module changes. This realizes a new method for laser feature point calibration and solves the inherent error caused by angular lasers from the laser emission end.

[0025] 10. This invention uses parallel laser as the basic research method for laser feature point calibration, which can provide an accurate data foundation for any subsequent laser correction involving angles. It has strong versatility and a wide range of applications. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of an embodiment of a laser feature point calibration device based on angle measurement according to the present invention; Figure 2 yes Figure 1 A magnified view of a portion of the image; Figure 3 This is a schematic diagram of the initial position of the feature point display module at time t0 and the position without pose change after translation at time ti in an embodiment of the present invention. The arrows in the diagram indicate the translation direction. Figure 4 This is a schematic diagram of the initial position of the feature point display module at time t0 and the position after rotation around the x-axis at time ti in an embodiment of the present invention. The arrows in the diagram indicate the direction of rotation around the x-axis. Figure 5 This is a schematic diagram of the initial position of the feature point display module at time t0 and the position after rotation around the y-axis at time ti in an embodiment of the present invention. The arrows in the diagram indicate the direction of rotation around the y-axis. Figure 6 This is a schematic diagram of the initial position of the feature point display module at time t0 and the position after rotation around the z-axis at time ti in an embodiment of the present invention. The arrows in the diagram indicate the direction of rotation around the z-axis. Figure 7 This is a schematic diagram of the initial position of the feature point display module at time t0 and the position after rotation around the x, y, and z axes at time ti in an embodiment of the present invention. The arrows in the diagram indicate the rotation directions around the x, y, and z axes.

[0027] In the diagram: 1-Laser emission module, 2-Pose adjustment module, 21-Translation adjustment unit, 22-Rotation adjustment unit; 3-Feature point display module, 4-Pose correction module, 41-First correction unit, 42-Second correction unit; 5-Angle measurement module, 51-First angle measurement unit, 52-Second angle measurement unit, 6-Image detection module. Detailed Implementation

[0028] To make the objectives, advantages, and features of the present invention clearer, the following detailed description of the laser feature point calibration device and method based on angle measurement proposed in this invention, in conjunction with the accompanying drawings and specific embodiments, will further clarify these points. The advantages and features of the present invention will become clearer from the following detailed embodiments.

[0029] See Figure 1 This embodiment is a laser feature point calibration device based on angle measurement, which mainly includes a laser emission 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.

[0030] The centers of the laser emitting module 1, the feature point display module 3, and the pose adjustment module 2 are all in the same plane. The laser emitting module 1 includes a laser, a laser sleeve, and corresponding adjustment and fixing screws. Taking the vertical line of the display surface of the feature point display module 3 as a reference, according to different calibration requirements, the laser emitted by the laser emitting module 1 is M beams of laser light parallel to the vertical line of the display surface, where M ≥ 1.

[0031] The feature point display module 3 is specifically a rectangular target surface. It is positioned on the emission path of the laser emission module 1, and its display surface intersects with the laser emitted by the laser emission module 1 to form a laser spot. A spatial coordinate system is established at the initial position of the feature point display module 3. In this embodiment, the longer side of the feature point display module 3 is the x-axis, the shorter side is the y-axis, and the direction perpendicular to the target surface is the z-axis. This spatial coordinate system conforms to the right-hand rule. In other embodiments of the invention, the spatial coordinate system can be defined in any direction within the target space, as long as the right-hand rule is satisfied.

[0032] The pose adjustment module 2 includes a translation adjustment unit 21 and a rotation adjustment unit 22. The translation adjustment unit 21 can be a conveyor belt mechanism or a conveyor shaft mechanism, etc., capable of realizing translational movement. The rotation adjustment unit 22 can be a rotation shaft mechanism, etc., capable of realizing rotational movement. The translational trajectory of the translation adjustment unit 21 is parallel to at least one laser beam emitted by the laser emitting module 1. The mounting end of the translation adjustment unit 21 is installed at the output end of the rotation adjustment unit 22, and the feature point display module 3 is installed at the output end of the translation adjustment unit 21. Through the coordinated cooperation of the translation adjustment unit 21 and the rotation adjustment unit 22, the translational and rotational pose of the feature point display module 3 can be adjusted.

[0033] The pose correction module 4 includes a first correction unit 41 and a second correction unit 42. Specifically, both the first correction unit 41 and the second correction unit 42 are reference mirrors, and are respectively mounted on the laser emission module 1 and the feature point display module 3. The angle measurement module 5 includes a first angle measurement unit 51 and a second angle measurement unit 52. Specifically, the first angle measurement unit 51 includes a theodolite and is mounted around the periphery of the laser emission module 1. The first angle measurement unit 51 corrects the first correction unit 41 and the second correction unit 42 to collimate the laser emission module 1 and the feature point display module 3. The second angle measurement unit 52 includes three theodolites, which are respectively mounted on the x-axis, y-axis, and z-axis of the feature point display module 3 to obtain the multi-dimensional angles of the feature point display module 3.

[0034] The image detection module 6 is a camera. The image detection module 6 is set on the side of the feature point display module 3 facing the laser emission module 1. Its field of view can at least cover the area where the laser spot is located on the feature point display module 3, and is used to acquire two-dimensional images containing the laser spot under different poses.

[0035] The input end of the central processing module is electrically connected to the output end of the image detection module 6. Based on 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 rotation axis center position of the feature point display module 3 is obtained. Then, based on the rotation axis center position, the two-dimensional coordinates of the laser spot after pose adjustment at the next moment are obtained based on the spatial coordinate system of the display surface of the feature point display module 3, so as to realize the laser feature point calibration.

[0036] When the pose change of the target being measured is extremely small, the specific implementation steps are as follows: Step 1: Adjust the position of the first angle measuring unit 51 and calibrate the first angle measuring unit 51 using the reference mirror placed on the laser emitting module 1.

[0037] Step 2: A laser beam, which has been adjusted to be parallel to the vertical line of the display surface of the feature point display module 3, is emitted through the laser emission module 1, so that it intersects with the display surface of the feature point display module 3 to form a laser spot.

[0038] Step 3: The reference mirror placed on the feature point display module 3 is collimated by the first angle measuring unit 51, and the pose of the feature point display module 3 is adjusted by the pose adjustment module 2 to achieve collimation between the laser emission module 1 and the feature point display module 3.

[0039] Step 4: Continue to adjust the pose of the feature point display module 3 through the pose adjustment module 2. During this process, the image detection module 6 acquires two-dimensional images containing laser spots under different poses, and the second angle measurement unit 52 acquires the multi-dimensional angles of the feature point display module 3 under different poses, that is, to realize the reading and recording of the roll angle, pitch angle and azimuth angle of the feature point display module 3.

[0040] Step 5: The central processing module obtains the rotation axis center position of the feature point display module 3 based on the two-dimensional image containing the laser spot under different poses and the multi-dimensional angle of the feature point display module 3 under different poses. Then, based on the rotation axis center position, the coordinates of the laser spot after pose adjustment based on the spatial coordinate system of the display surface of the feature point display module 3 are obtained, thereby realizing laser feature point calibration.

[0041] In the initial state, the feature point display module 3 is defined as follows: the angle generated by rotating around the x-axis is the pitch angle β, the angle generated by rotating around the y-axis is the azimuth angle α, and the angle generated by rotating around the z-axis is the roll angle. See also Figure 2 When the pose adjustment module 2 adjusts the pose of the feature point display module 3, the pitch angle β, azimuth angle α, and roll angle are... The location is the center position of the rotation axis, P(m, n, p).

[0042] The laser spot A before and after the pose adjustment module 2 can be represented by a spatial vector: ; After adjustment Before adjustment by pose adjustment module 2, the coordinates of laser spot A are: The coordinates of the adjusted laser spot A are: .

[0043] and It can be expressed as: ; and The rotation matrix between them can be represented as: ; ; ; Since the error generated during the adjustment by pose adjustment module 2 is very small, the three rotation matrices can be approximately written as the following formula: ; ; ; , , These are the roll rotation matrix, pitch rotation matrix, and azimuth rotation matrix, respectively. See also Figure 7 The formula relating the position coordinates of the laser spot A before and after the feature point display module 3 is rotated around the x-axis, y-axis, and z-axis can be expressed as: ; See Figure 4 With pitch angle For example, we can obtain the formula for the position coordinate relationship of laser spot A before and after adjustment: ; See Figure 5 , by azimuth For example, we can obtain the formula for the position coordinate relationship of laser spot A before and after adjustment: ; See Figure 6 With roll angle For example, we can obtain the formula for the position coordinate relationship of laser spot A before and after adjustment: ; See Figure 3 Pose adjustment includes position and attitude adjustment. All pose adjustments can be viewed as first adjusting the position and then adjusting the attitude. When the included angle is the roll angle... At that time, the rotation axis center position P(m, n, p) refers to the attitude adjustment after the position adjustment is completed, and the position adjustment is for the movement of the z-axis position. It can be seen that... Seeking Meanwhile, it is known that the coordinate point p in the center position P(m,n,p) of the rotation axis is always 0, so it is omitted in subsequent calculations.

[0044] Substituting into the above formula, we get the following formula: ; Based on the above formula, the position coordinate formula of the center position P(m, n, p) of the rotation axis can be obtained: ; Similarly, the above method can be used to obtain the position coordinate formulas for the rotation axis position P based on other different adjustment angles: 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: ; 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: .

[0045] The specific implementation steps when the pose of the target being measured changes significantly differ from those when the pose of the target being measured changes very little in steps 2 and 5, while the remaining steps are the same.

[0046] Step 2: The laser emitted by the laser emitting module 1 consists of 3 laser beams, all parallel to the vertical line of the display surface of the feature point display module 3. The 3 laser beams intersect with the display surface of the feature point display module 3 to form 3 laser spots.

[0047] The position of the center of rotation axis in step 5 is calculated as follows: In the initial state, the two-dimensional coordinates of the three laser spots on the display surface of the feature point display module 3 are defined as follows: , , After adjustment, the two-dimensional coordinates in any pose are as follows: , , ; When the feature point display module 3 rotates around the z-axis, a roll angle is generated. At that time, 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: ; definition: , ; The above formula can be converted to: ;

[0048] Based on the position of the rotation axis center, the coordinates of the laser spot after pose adjustment at the next moment can be obtained in the spatial coordinate system of the display surface of the feature point display module 3.

[0049] Simultaneously, the translation error of the pre-calibrated pose adjustment module 2 can be added to the original laser spot coordinates to perform displacement correction in the laser translation direction. Furthermore, the pose of the feature point display module 3 can be corrected based on the multi-dimensional angles of the feature point display module 3 measured by the second angle measuring unit 52 and the three parallel laser beams, as well as the pose of other laser beams incident on the display surface of the feature point display module 3 at any other angle.

Claims

1. A laser feature point calibration device based on angle measurement, characterized in that: It includes a laser emission 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 to emit laser light; The feature point display module (3) is set in the emission optical path of the laser emission module (1), and its display surface intersects with the laser emitted by the laser emission module (1) to form a laser spot; The output of the pose adjustment module (2) is connected to the feature point display module (3) and is used to adjust the pose of the feature point display module (3); The pose correction module (4) includes a first correction unit (41) and a second correction unit (42), which are respectively disposed on the laser emission module (1) and the feature point display module (3); The angle measuring module (5) includes a first angle measuring unit (51) and a second angle measuring unit (52); the first angle measuring unit (51) and the second angle measuring unit (52) are respectively disposed on the periphery of the laser emitting module (1) and the feature point display module (3); the first angle measuring unit (51) is used to collimate 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); the second angle measuring unit (52) is used to obtain the multi-dimensional angle of the feature point display module (3); The image detection module (6) is set on the side of the feature point display module (3) facing the laser emission module (1), and its field of view can at least cover the area where the laser spot is located on the feature point display module (3) to obtain two-dimensional images containing laser spots under different poses; The input end of the central processing module is electrically connected to the output end of the image detection module (6). It is used to obtain the rotation axis center position of the feature point display module (3) based on 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). Then, based on the rotation axis center position, it obtains the coordinates of the laser spot after pose adjustment at the next moment based on the spatial coordinate system of the display surface of the feature point display module (3) 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 also used to correct the displacement of the laser translation direction based on the coordinates of the laser spot and the translation error of the pre-calibrated pose adjustment module (2).

3. A laser feature point calibration device based on angle measurement according to claim 1 or 2, characterized in that: With reference to the vertical line of the display surface of the feature point display module (3), the laser emitted by the laser emission module (1) is M beams of laser parallel to the vertical line of the display surface, M≥1; The central processing module is also used to correct the pose of the feature point display module (3) based on the multidimensional angles of the feature point display module (3) measured by the second angle measuring unit (52) and the M-beams of laser emitted by the laser emitting module (1) that are parallel to the vertical line of the display surface, as well as other arbitrary angle lasers incident on 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) includes a translation adjustment unit (21) and a rotation adjustment unit (22). The translational trajectory of the translation adjustment unit (21) is parallel to at least one laser beam emitted by the laser emission module (1); The mounting end of the translation adjustment unit (21) is installed at the output end of the rotation adjustment unit (22), and the feature point display module (3) is installed at 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 conveyor shaft mechanism, and the rotation adjustment unit (22) is a rotation 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; Define the longer side of the target surface as the x-axis, the shorter side as the y-axis, and the direction perpendicular to the target surface as the z-axis; The first angle measuring unit (51) includes one theodolite, and the second angle measuring unit (52) includes three theodolites; The three theodolites in the second angle measuring unit (52) are respectively set 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, employing the laser feature point calibration device based on angle measurement as described in any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Adjust the position of the first angle measuring unit (51) and calibrate the first angle measuring unit (51) through the first correction unit (41). Step 2: The laser is emitted from the laser emitting module (1) to the feature point display module (3) to form a laser spot on its display surface; Step 3: The first angle measuring unit (51) is used to collimate the second correction unit (42), and then the pose adjustment module (2) is used to adjust the pose of the feature point display module (3) to achieve the collimation of the laser emission module (1) and the feature point display module (3); Step 4: Continue to adjust the pose of the feature point display module (3) through the pose adjustment module (2). During this process, the image detection module (6) acquires two-dimensional images containing laser spots under different poses, and the second angle measuring unit (52) acquires the multi-dimensional angles of the feature point display module (3) under different poses. Step 5: The central processing module obtains the rotation axis center position of the feature point display module (3) based on the two-dimensional image containing the laser spot under different poses and the multi-dimensional angle of the feature point display module (3) under different poses. Then, based on the rotation axis center position, the coordinates of the laser spot after pose adjustment at the next moment are obtained based on the spatial coordinate system of the display surface of the feature point display module (3), 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 emitting module (1) is a laser beam parallel to the vertical line of the display surface of the feature point display module (3); In the initial state, the coordinates of a laser spot on the display surface of the feature point display module (3) are defined as follows: After adjustment, the coordinates of the laser spot at any pose are: The feature point display module (3) rotates around the x-axis, generating the pitch angle β, the azimuth angle α, and the roll angle α. When the pose adjustment module (2) adjusts the pose of the feature point display module (3), 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); In step 5, when the included angle is the roll angle At that time, 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 formula: ； 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... The following formula is used for calculation: ； When the included angle is azimuth angle α, the coordinate point m in the center position P(m, n, p) of the rotation axis is always 0, and the coordinate point and The following formula is used for calculation: ； When the included angle is composed of pitch angle β, azimuth angle α, and roll angle During assembly, the coordinates of point m, n, and p in the center position P(m, n, p) of the rotation axis are... and The following formula is used for calculation: 。 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 emitting module (1) consists of three laser beams, all of which are parallel to the vertical line 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 the roll angle. Roll angle The location is the center position of the rotation axis P(m, n, p); the coordinate point p in the center position of the rotation axis 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 as follows: , , After adjustment, the two-dimensional coordinates in any pose are as follows: , , ; In step 5, the coordinates of points m and n in the center position P(m, n, p) of the rotation axis are calculated using the following formula: ； ； 。

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