An eye-hand calibration method for improving tracking and positioning accuracy of a line laser profiler

Abstract

This invention provides a hand-eye calibration method to improve the tracking and positioning accuracy of a line laser profilometer. The method includes an actuator, a line laser profilometer, a calibration plane, and a calibration block. The steps include: adjusting the line laser profilometer to be perpendicular to the calibration plane and ensuring the laser line falls on the calibration line; collecting a set of blind zone information for calibration; obtaining the origin of the line laser profilometer; obtaining the direction of the laser angle bisector of the line laser profilometer; and obtaining the coordinate system transformation relationship between the line laser profilometer and the end effector of the actuator. The technical solution provided by this invention, by adjusting the position of the calibration block in the laser plane of the laser profilometer, forms a blind zone that blocks the laser, thereby calibrating the coordinate system transformation matrix between the laser of the line laser profilometer and the coordinate system of the actuator. This is beneficial for accurately controlling the laser position and attitude of the line laser profilometer, and eliminates the need for custom high-precision calibration objects, making the operation simple.

Description

Technical Field

[0001] This invention relates to the field of laser calibration technology, and in particular to a hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer. Background Technology

[0002] In industrial robot systems, line laser profilometers are frequently used for collaborative operations, such as precise scanning of local areas to obtain accurate feature information for image stitching, or simulating tool postures to inspect the target's working path. Therefore, in practical applications, hand-eye calibration of the line laser is necessary to obtain the transformation relationship between different coordinate systems. Because the imaging structure and principle of a line laser profilometer differ from traditional camera sensors, the calibration method for its coordinate transformation relationship with the actuator also differs from that of camera calibration.

[0003] Several line laser calibration methods exist in the prior art. For example, patent document CN116734730A proposes a machine tool line laser calibration method based on a standard sphere. A profilometer scans the entire standard sphere from different directions to collect scanning data. Based on the collected 3D point cloud data, the sphere center coordinates corresponding to each point cloud in different scanning directions are extracted. Based on the scanning direction and the sphere center coordinates, the rotation and translation RT matrix is ​​calculated to obtain the relative positional relationship of the line laser with respect to the machine tool spindle, thus completing the line laser calibration. Patent document CN114670203A proposes a laser vision method. A method for guiding automatic welding hand-eye calibration of a robot is proposed. This method designs a customized three-dimensional calibration plate with three calibration points. The moving robot arm collects the line laser calibration lines projected onto the three-dimensional calibration plate through a line laser sensor to obtain calibration feature points and complete hand-eye calibration. Patent document CN115284330A proposes a method for calibrating a laser profilometer for a welding robot. This method uses a measurement method to calibrate the origin of the laser profilometer coordinate system. At the same time, the position of the profilometer and the calibration surface is adjusted by a level and a profilometer line. The attitude of the laser profilometer coordinate system is calibrated by applying the ABC-2 point method.

[0004] In summary, current line laser calibration methods mostly rely on high-precision customized 3D calibration blocks, such as calibration spheres, cones, or 3D calibration stages with customized special structures and feature points. The calibration objects are either structurally complex or have high requirements for processing accuracy and dimensions. The calibration results generally rely on data collected by a profilometer for intermediate calculation, and are therefore also affected by the accuracy of the profilometer. A few calibration methods use measurement methods, which rely on the rotation operation of the actuator, such as the robotic arm, and the changes in the x and z values ​​displayed by the profilometer itself to estimate the origin position. The coordinate system axis direction is obtained by adjusting the upper surface of the laser profilometer to be parallel to the horizontal panel using a level. These methods rely on the combined results of the robotic arm rotation accuracy, the profilometer accuracy, and the shell information, rather than originating from the measurement and calibration of the laser itself. Summary of the Invention

[0005] This invention aims to solve the above problems and provides a hand-eye calibration method to improve the tracking and positioning accuracy of a line laser profilometer. It avoids using quantitative data from the profilometer to calculate features and transfer calculation errors. The method is simple to operate, does not rely on high-precision calibration materials, and has high stability and accuracy of calibration results.

[0006] The present invention solves the aforementioned problem by employing the following technical solution: a hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer, comprising an actuator, a line laser profilometer, a calibration plane, and a calibration block. The line laser profilometer is rigidly connected to the end of the actuator via a mounting component. A calibration line is provided on the calibration plane. When the calibration block is placed on the calibration plane, the contact area between the lower surface of the calibration block and the calibration plane is included within the projection area of ​​the upper surface of the calibration block onto the calibration plane. The coordinate system of the line laser profilometer is set according to the geometric characteristics of the laser plane of the line laser profilometer. The origin of the coordinate system is the intersection point of the laser rays, the direction of the second coordinate axis is parallel to the normal direction of the plane containing the laser, the direction of the third coordinate axis is parallel to the direction of the laser angle bisector, and the direction of the first coordinate axis is the cross product direction of the second and third coordinate axes. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer includes the following steps:

[0007] Sa: The laser profilometer is perpendicular to the calibration plane, and the laser line falls on the calibration straight line.

[0008] Sa1 is placed horizontally on the calibration plane;

[0009] Sa2 adjusts the position of the end of the actuator, causing the line laser profiler to move so that the plane where the laser of the line laser profiler is located is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane where the laser of the line laser profiler is located is parallel to the line in the calibration plane that is perpendicular to the calibration line.

[0010] Sa3 adjusts the end of the actuator to translate along the normal direction of the calibration plane, so that the two endpoints A and B of the laser line AB formed by the laser of the line laser profilometer and the calibration plane both fall on the calibration plane and within the preset area of ​​the calibration line;

[0011] Sa4 records the pose Pose0 of the actuator end effector in the first coordinate system at this time;

[0012] Sb collects blind zone information set for calibration.

[0013] Sb1 places the calibration block within the laser line AB;

[0014] Sb2 adjusts the position of the calibration block so that the calibration block forms a laser blind zone on the calibration plane, and records it as position i;

[0015] Sb3 measures and records the K blind zone information formed by the laser of the line laser profilometer and the edge of the calibration block at position i, where K=1 or 2. The blind zone information includes the position information of the calibration block edge point forming the blind zone and the position information of the laser endpoint of the blind zone edge. The position information of the calibration block edge point forming the blind zone is the position information of the upper surface edge point of the calibration block forming the blind zone on the calibration line and the height difference between the upper surface edge point and the calibration line. The position information of the laser endpoint of the blind zone edge is the position information of the laser line endpoint near the blind zone on the calibration line.

[0016] Sb4 Repeat steps Sb2 and Sb3, in which the calibration block moves N positions within the laser line AB, where N≥1, and obtains a total of M blind zone information, where M≥2;

[0017] Sc obtains the origin of the line laser profilometer

[0018] Sc1 obtains the blind zone shaping laser ray information corresponding to each blind zone through M blind zone information, forming a blind zone shaping laser ray information set; the blind zone shaping laser ray information is a parameter that can express the equation information of the line where the ray is located;

[0019] Based on the set of blind zone forming laser ray information, Sc2 calculates the intersection of all blind zone forming laser rays to obtain the coordinate information of the origin O of the line laser profilometer in the calibration plane coordinate system;

[0020] Sd obtains the direction of the laser angle bisector of the line laser profilometer.

[0021] Sd1 obtains the left edge contour line OA of the laser based on the coordinate information of the origin O of the line laser profilometer and the endpoint A of the laser line AB.

[0022] Sd2 obtains the right edge contour line OB of the laser based on the coordinate information of the origin O of the line laser profilometer and the endpoint B of the laser line AB.

[0023] Sd3 calculates the angle bisector direction and included angle of the left edge contour line OA and the right edge contour line OB of the laser.

[0024] Se obtains the coordinate system transformation relationship between the line laser profilometer and the end effector.

[0025] Se1 obtains the coordinate system transformation relationship H between the line laser profilometer and the calibration plane using the coordinates of the origin O of the line laser profilometer, the direction of the laser angle bisector of the line laser profilometer, the direction of the calibration line, and the direction of the preset coordinate axes of the line laser profilometer. C The calibration line is parallel to the first coordinate axis of the line laser profilometer.

[0026] Se2 calculates the coordinate system transformation relationship between the line laser profilometer and the end of the actuator by calibrating the transformation matrix between the planar coordinate system and the first coordinate system and the pose Pose0 of the actuator end in the first coordinate system.

[0027] In step Sa2, the pose of the end effector is adjusted to move the line laser profilometer, so that the plane containing the laser of the line laser profilometer is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane containing the laser of the line laser profilometer is parallel to a line in the calibration plane that is perpendicular to the calibration line, including:

[0028] Sa21 constructs a second coordinate system with the calibration line, the calibration plane normal, and a point on the calibration line as the origin. The coordinate transformation matrix between the second coordinate system and the end of the actuator has been calibrated.

[0029] Sa22 adjusts the position of the end of the actuator, causing the line laser profiler to move, so that the laser line of the line laser profiler on the calibration plane falls on the calibration line, which is denoted as position P1;

[0030] Sa23 controls the end of the actuator to translate, moving it to position P2 along the normal direction of the calibration plane, and records the moving distance L and the distance d between the laser line and the calibration line;

[0031] Sa24 estimates the angle between the plane containing the laser and the normal to the calibration plane as α = arctan(d / L);

[0032] Sa25 controls the actuator to translate back to position P1;

[0033] Sa26 controls the actuator to rotate around the axis containing the calibration line by an angle a degrees;

[0034] Sa27 controls the end of the actuator to translate, moving it to position P3 along the normal direction of the calibration plane, and observes the distance difference between the laser line and the calibration line; if the distance difference is greater than the threshold, the adjustment steps are repeated; if the distance difference is less than the threshold, the adjustment is completed so that the plane where the laser of the line laser profilometer is located is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line.

[0035] At this time, the normal of the plane in which the laser of the line laser profilometer is located is parallel to the straight line in the calibration plane that is perpendicular to the calibration line.

[0036] The actuator is a robotic arm. In step Sa2, the position and orientation of the end effector of the actuator are adjusted to move the line laser profilometer, so that the plane containing the laser of the line laser profilometer is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane containing the laser of the line laser profilometer is parallel to a line in the calibration plane that is perpendicular to the calibration line, including:

[0037] Sa21 adjusts the position and orientation of the end of the actuator, drives the line laser profiler to move, so that the laser line of the line laser profiler on the calibration plane falls on the calibration line, and records the coordinates Q1 of the end of the actuator.

[0038] Sa22 controls the actuator to move the line laser profilometer along the calibration line to a preset position, and records the coordinates Q2 of the end of the actuator;

[0039] Sa23 controls the actuator to move the line laser profilometer away from or closer to the calibration plane, keeping the laser line on the calibration line, and records the coordinates Q3 of the actuator end point;

[0040] The Sa24 three-point method is used to construct a third coordinate system, where Q1 is the origin. The X-axis is the axis of intersection with the x-axis. , The axis perpendicular to the plane is the Z-axis;

[0041] Sa25 obtains the angle between the Z-axis of the third coordinate system and the normal to the calibration plane, and controls the actuator to rotate around... Rotate the corresponding angle along the X-axis;

[0042] Sa26 controls the end of the actuator to translate, moving it to position Q4 along the normal direction of the calibration plane, and observes the distance difference between the laser line and the calibration line; if the distance difference is greater than the threshold, the adjustment steps are repeated; if the distance difference is less than the threshold, the adjustment is completed so that the plane where the laser of the line laser profilometer is located is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line.

[0043] At this time, the normal of the plane in which the laser of the line laser profilometer is located is parallel to the line in the calibration plane that is perpendicular to the calibration line.

[0044] Step Sc1 obtains the blind zone shaping laser ray information corresponding to each of the M blind zone information, forming a blind zone shaping laser ray information set, including:

[0045] For the j-th blind zone information, Sc11 calculates the parameters of the equation of the line containing the laser ray that forms the blind zone.

[0046] The coordinates of the laser point at the edge of the calibration block forming the blind zone are obtained by using the position information of the edge point of the calibration block forming the blind zone and the height difference with the calibration line. The coordinates of the laser endpoint at the edge of the blind zone are obtained by using the position information of the laser endpoint at the edge of the blind zone. The parameters of the equation information of the line containing the laser ray forming the blind zone are obtained based on the two-point method. Alternatively, the laser ray angle is obtained by using the position information of the edge point of the calibration block forming the blind zone, the position information of the laser endpoint at the edge of the blind zone, and the height difference with the calibration line. The coordinates of the laser endpoint at the edge of the blind zone are obtained by using the position information of the laser endpoint at the edge of the blind zone. The parameters of the equation information of the line containing the laser ray forming the blind zone are obtained by using the coordinates of the laser endpoint at the edge of the blind zone and the laser ray angle.

[0047] Sc12 repeats step Sc11 to obtain the parameters of the linear equation information of the laser rays forming the blind zone in group M, and forms a set of laser ray information for blind zone formation.

[0048] The Sc step, which obtains the origin of the line laser profilometer, also includes: Sc3, which evaluates the error of the reprojection position information of the laser endpoint at the edge of the blind zone.

[0049] For each blind zone, the intersection of the line connecting the origin O of the line laser profilometer and the edge point of the calibration block forming the blind zone with the calibration plane is calculated using the position information of the edge point of the calibration block forming the blind zone, thereby obtaining the reprojection position information of the laser endpoint at the edge of the blind zone.

[0050] Calculate the reprojection position information of the laser endpoint at the edge of the blind zone and the reprojection error of the laser endpoint position at the edge of the blind zone;

[0051] Calculate the reprojection error of all blind areas, filter out points with excessive errors according to the preset threshold, and recalculate the origin O of the line laser profilometer after removing the corresponding points, or repeat steps Sc1-Sc2 to supplement new blind area information and recalculate and evaluate the origin of the line laser profilometer until the reprojection error is within the preset threshold range.

[0052] The calibration block is a rectangular block; in step Sb2, the position of the calibration block is adjusted so that the calibration block forms a laser blind zone on the calibration plane, including: adjusting any side of the calibration block to be perpendicular to the laser line AB, and obtaining the edge position information of the calibration block forming the blind zone by using the intersection point information of the rectangular block edge forming the laser blind zone and the calibration line and the height information of the calibration block.

[0053] The direction of the calibration line is parallel to the X-axis or Y-axis direction of the calibration plane.

[0054] In step Se1, the coordinate system transformation relationship H between the line laser profilometer and the calibration plane is obtained using the coordinates of the origin O of the line laser profilometer, the direction of the laser angle bisector of the line laser profilometer, the direction of the calibration line, and the direction of the preset coordinate axis of the line laser profilometer. C ,include:

[0055] Obtain the angle β between the laser angle bisector of the line laser profilometer and the normal of the calibration plane;

[0056] The origin of the calibration plane coordinate system is translated to the origin O of the line laser profilometer to construct a third coordinate system. In the third coordinate system, the actuator is controlled to rotate by an angle β around an axis perpendicular to the calibration line in the calibration plane, so that the direction of the laser angle bisector of the line laser profilometer is perpendicular to the calibration plane.

[0057] Based on the preset coordinate system of the line laser profilometer, the coordinate system transformation relationship H between the line laser profilometer and the calibration plane is obtained through the perpendicular relationship between the laser plane direction and the calibration line, the parallel relationship between the laser angle bisector direction of the line laser profilometer and the normal of the calibration plane, and the origin O of the line laser profilometer. C .

[0058] The calibration line is marked with scale markings to indicate distances, which are used to quickly obtain information about the blind zone.

[0059] The first coordinate system is the actuator base coordinate system or the calibration plane coordinate system.

[0060] The beneficial effects of this invention are as follows: By adjusting the position of the calibration block in the laser plane of the laser profilometer, a blind zone of laser occlusion is formed, and the calibration origin of the line laser profilometer and the direction of the line laser angle bisector are obtained to calibrate the position and pose relationship of the line laser profilometer in the calibration plane. This allows for the direct calibration of the coordinate system transformation matrix between the laser of the line laser profilometer and the coordinate system of the actuator, which is beneficial for accurately controlling the laser position and attitude of the line laser profilometer.

[0061] This method uses readily available, conventionally shaped objects as calibration blocks, enabling rapid calibration even in scenarios lacking high-precision 3D calibration spheres or custom-designed calibration materials. The method is simple and easy to operate. It calculates intersections using multiple rays within the laser projection range, combining reprojection error assessment with anomaly data filtering to improve the stability and accuracy of the calibration results. Simultaneously, it avoids using profilometer data for feature calculations, reducing laser plane calibration errors caused by contour data errors. This ensures the calibrated laser line accurately hits the target contour, facilitating subsequent measurements, safety checks, and adaptive scan planning.

[0062] Furthermore, this method directly calibrates the physical spatial position of the line laser plane by constructing a coordinate system based on the laser plane normal, the laser angle bisector, and the laser emission point. This better matches the intuitive understanding of the line laser imaging plane in the principle of the line laser profilometer, making it easier to accurately control the attitude of the line laser profilometer and enabling the calibrated laser line profile to be projected onto the target path according to the predetermined design.

[0063] The geometric shape information of the emitted laser is calibrated to obtain the physical origin and divergence angle of the laser plane. The positional relationship between the profilometer and the object can be adaptively adjusted according to the sampling accuracy or time consumption requirements, thereby adjusting the acquisition width of the laser profile on the target object.

[0064] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0065] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0066] Figure 1 This is a schematic diagram of the implementation environment of the present invention;

[0067] Figure 2 This is a flowchart of the calibration method of the present invention;

[0068] Figure 3 This is a schematic diagram showing the laser blind zone formed by the calibration block on the calibration plane in this invention;

[0069] Figure 4 This is a schematic diagram showing the calibration block located at different positions within the laser line AB in this invention;

[0070] Figure 5 This is a schematic diagram of the movement of the end of the control actuator along the normal direction of the calibration plane in this invention. Detailed Implementation

[0071] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0072] A hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer, implemented in an environment such as... Figure 2 As shown, it includes an actuator 1, a line laser profilometer 2, and a calibration plane 3. The line laser profilometer 2 is rigidly connected to the end of the actuator 1 through a mounting component. A calibration line is provided on the calibration plane 3. The actuator 1 can be a robotic arm, a robotic hand, or other mechanism.

[0073] The implementation environment also includes a calibration block. When the calibration block is placed on the calibration plane, the contact area between the lower surface of the calibration block and the calibration plane is included in the projection area of ​​the upper surface of the calibration block onto the calibration plane. Figure 3 The diagram illustrates calibration blocks of different shapes, including rectangular and inverted trapezoidal calibration blocks. When these shaped calibration blocks are placed on the calibration plane, the contact area between the lower surface of the calibration block and the calibration plane is included in the projection area of ​​the upper surface of the calibration block onto the calibration plane. Figure 3 The line laser profilometer is illustrated by a cylinder, and the plane containing the laser is illustrated by a triangle within a dashed outline. The laser plane of the line laser profilometer intersects with the calibration plane to form a laser line.

[0074] The coordinate system of the line laser profilometer is set according to the geometric characteristics of the laser plane of the line laser profilometer. The origin of the coordinate system of the line laser profilometer is the intersection point of the laser rays. The direction of the second coordinate axis is parallel to the normal of the plane where the laser is located. The direction of the third coordinate axis is parallel to the direction of the laser angle bisector. The direction of the first coordinate axis is the cross product direction of the second and third coordinate axes.

[0075] Hand-eye calibration methods to improve the tracking and positioning accuracy of line laser profilometers, such as... Figure 1 As shown, it includes the following steps:

[0076] Sa: The laser profilometer is perpendicular to the calibration plane, and the laser line falls on the calibration straight line.

[0077] Sa1 is placed horizontally on the calibration plane;

[0078] Sa2 adjusts the pose of the actuator end effector, causing the line laser profilometer to move so that the plane containing the laser of the line laser profilometer is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane containing the laser of the line laser profilometer is parallel to the line in the calibration plane that is perpendicular to the calibration line. The calibration plane coordinate system has been established, and the transformation matrix between the calibration plane coordinate system and the actuator base coordinate system has been calibrated. The position information of the calibration line in the calibration plane coordinate system can be pre-calibrated or obtained through conventional methods.

[0079] Sa3 adjusts the actuator end to translate along the normal direction of the calibration plane so that the two endpoints A and B of the laser line AB formed by the laser of the line laser profilometer and the calibration plane both fall on the calibration plane and within the preset area of ​​the calibration line;

[0080] Sa4 records the pose Pose0 of the actuator end effector in the first coordinate system at this time.

[0081] Points A and B lie on the calibration line, and their coordinate information can be obtained through the calibration line information. For example, if the direction and endpoints of the calibration line have been calibrated, the coordinates of points A and B can be obtained through the direction vector and distance difference. If the direction of the calibration line is parallel to the calibration plane coordinate system, the coordinate values ​​of the endpoints on the calibration plane can be obtained directly.

[0082] The preset area can have marked points or scale lines to facilitate the measurement or reading of location-related values.

[0083] When setting the position of the actuator end, the height of the actuator from the calibration plane is adjusted so that when the calibration block is placed in the plane of the laser and moves along the AB direction, there is a region that can form a blind zone at both ends of the calibration block. Generally, the calibration block should not be too high.

[0084] Sb collects blind zone information set for calibration.

[0085] Sb1 places the calibration block within the laser line AB;

[0086] Sb2 adjusts the position of the calibration block so that the calibration block forms a laser blind zone on the calibration plane, such as... Figure 4 As shown in the left figure, the location is recorded as i; the laser blind zone is the area on the calibration plane where the laser line formed by the placement of the calibration block is blocked and not physically occupied by the calibration block when no calibration block is placed.

[0087] The Sb3 measurement and recording line laser profilometer records K blind zone information formed by the laser and the edge of the calibration block at position i, where K=1 or 2. The blind zone information includes the position information of the calibration block edge point forming the blind zone and the position information of the laser endpoint at the edge of the blind zone. The position information of the calibration block edge point forming the blind zone is the position information of the upper surface edge point of the calibration block forming the blind zone on the calibration line and the height difference between the upper surface edge point and the calibration line. The position information of the laser endpoint at the edge of the blind zone is the position information of the laser line endpoint near the blind zone on the calibration line.

[0088] Sb4 Repeat steps Sb2 and Sb3, moving the calibration block N positions within the laser line AB, such as... Figure 4 As shown in the right figure, N≥1, and a total of M blind zone information are obtained, M≥2.

[0089] In a specific embodiment, the method for obtaining the position information of the edge point of the calibration block forming the blind zone is as follows: Utilizing the rectangular block, which is a structure where the height and projected position information can be easily read directly, after adjusting one side of the rectangular block to be perpendicular to the calibration line, the position information of the edge point of the upper surface of the calibration block forming the blind zone on the calibration line can be measured by measuring the position of the calibration block forming the blind zone on the calibration line. For example, the position information can be obtained by measuring the distance between the calibration block forming the blind zone and a specific point on the calibration line, such as a marked point, or by directly reading the scale by setting a scale line on the calibration line. Alternatively, the position information can be obtained by directly measuring the width between the calibration block forming the blind zone and the laser endpoint position of the blind zone edge.

[0090] In another embodiment, a calibration block with a large upper surface projection, such as an inverted trapezoidal calibration block, is used. For structures with large upper surface projections, such as... Figure 3 As shown in the right figure, measuring tools, such as a right-angle ruler, can be used to measure the height of the edge point of the upper surface of the surface forming the blind zone of the calibration block on the calibration plane and the projection position information on the calibration line.

[0091] The position information of the laser endpoint at the edge of the blind zone can be obtained by directly measuring with a measuring tool or by directly reading the scale by setting a scale line on the calibration line.

[0092] Sc obtains the origin of the line laser profilometer

[0093] Sc1 obtains the blind zone shaping laser ray information corresponding to each blind zone through M blind zone information, forming a blind zone shaping laser ray information set; the blind zone shaping laser ray information is a parameter that can express the equation information of the line where the ray is located;

[0094] The blind zone forming laser ray information includes, for example, the coordinates of the laser endpoint at the edge of the blind zone, and the coordinates of the edge point of the upper surface of the surface on which the calibration block forms the blind zone. In this case, the blind zone forming laser ray information is obtained through the coordinates of two points on a straight line; or the coordinates of the laser endpoint at the edge of the blind zone and the angle of the blind zone forming laser ray. The angle of the blind zone forming laser ray can be calculated by arctan(blind zone width / height) or 180°-arctan(blind zone width / height). In this case, the blind zone forming laser ray information is obtained through a point on a straight line and the direction of the straight line.

[0095] Based on the set of blind zone forming laser ray information, Sc2 calculates the intersection points of all blind zone forming laser rays to obtain the coordinate information of the origin O of the line laser profilometer in the calibration plane coordinate system.

[0096] In one embodiment, the origin can be obtained by solving a simultaneous equation to find the minimum error or the mean of the intersection points.

[0097] Sd obtains the direction of the laser angle bisector of the line laser profilometer.

[0098] Sd1 obtains the left edge contour line OA of the laser based on the coordinate information of the origin O of the line laser profilometer and the endpoint A of the laser line AB.

[0099] Sd2 obtains the right edge contour line OB of the laser based on the coordinate information of the origin O of the line laser profilometer and the endpoint B of the laser line AB.

[0100] Sd3 calculations obtain the direction and angle of the angle bisector of the left edge contour line OA and the right edge contour line OB of the laser.

[0101] Se obtains the coordinate system transformation relationship between the line laser profilometer and the end effector.

[0102] Se1 obtains the coordinate system transformation relationship H between the line laser profilometer and the calibration plane by using the coordinates of the origin O of the line laser profilometer, the direction of the laser angle bisector of the line laser profilometer, the direction of the calibration line, and the direction of the preset coordinate axes of the line laser profilometer. C The calibration line is parallel to the first coordinate axis of the line laser profilometer. The direction of the calibration line in the calibration plane has been calibrated. If the calibration line is used as the x-axis, the normal to the calibration plane through the calibration line is used as the Z-axis, and a point on the calibration line is the origin, a second coordinate system is constructed. In step Sa, the plane containing the laser of the line laser profilometer coincides with the XOZ plane of the second coordinate system. Measurements on the calibration line can be converted to measurements (X, 0, Z) in the XOZ plane. By calculating the origin position and angle bisector direction of the line laser profilometer, the translation in the XOZ plane and the rotation around the Y-axis of the second coordinate system can be obtained. Thus, the coordinate system transformation relationship between the line laser profilometer and the second coordinate system can be obtained. Then, through the pose relationship between the calibration line in the second coordinate system and the calibration plane, the coordinate system transformation relationship H between the line laser profilometer and the calibration plane can be calculated. C ;

[0103] Se2 calculates the coordinate system transformation relationship between the line laser profilometer and the actuator end via the transformation matrix between the calibration plane coordinate system and the first coordinate system and the pose Pose0 of the actuator end in the first coordinate system; the first coordinate system can be either the actuator base coordinate system or the calibration plane coordinate system.

[0104] In one embodiment, in step Sa2, the pose of the end effector is adjusted to move the line laser profiler, so that the plane containing the laser of the line laser profiler is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane containing the laser of the line laser profiler is parallel to the line perpendicular to the calibration line in the calibration plane. The following method is used:

[0105] Sa21 constructs a second coordinate system with the calibration line, the calibration plane normal, and a point on the calibration line as the origin. The coordinate transformation matrix between the second coordinate system and the end of the actuator has been calibrated.

[0106] Sa22 adjusts the position of the end of the actuator, causing the line laser profiler to move so that the laser line of the line laser profiler on the calibration plane falls on the calibration line, which is recorded as position P1.

[0107] Sa23 controls the translation of the end effector of the actuator, such as Figure 5 As shown, move along the normal direction of the calibration plane to position P2, and record the moving distance L and the distance d between the laser line and the calibration line;

[0108] Sa24 estimates the angle between the plane containing the laser and the normal to the calibration plane as α = arctan(d / L);

[0109] Sa25 controls the actuator to translate back to position P1;

[0110] The Sa26 controls the actuator to rotate by an angle 'a' degrees around the axis of the calibration line; since the laser line is on the calibration line at this time, after rotating around the calibration line, the laser line is still on the calibration line, and the laser plane of the line laser profiler is perpendicular to the calibration plane;

[0111] Sa27 controls the end of the actuator to translate, moving along the normal direction of the calibration plane to position P3, and observes the distance difference between the laser line and the calibration line; if the distance difference is greater than the threshold, the adjustment steps are repeated; if the distance difference is less than the threshold, the adjustment is completed so that the plane where the laser of the line laser profilometer is located is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line; at this time, the normal of the plane where the laser of the line laser profilometer is located is parallel to the line in the calibration plane that is perpendicular to the calibration line.

[0112] In actual implementation, the distance of position P1 is generally higher than that of positions P2 and P3. This is because the longer the distance, the longer the straight line, and the less likely it is to produce a straight line rotation error after aligning with the straight line mark. Therefore, position P2 is selected as close as possible to the calibration plane and can form a laser line. The longer moving distance L can reduce the angle calculation error. Position P3 is generally selected as the closest position between the profilometer and the surface to be measured that is adapted to the current measurement target, to ensure that the error meets the requirements within the application scenario.

[0113] In a preferred embodiment, when adjusting the end pose of the actuator, the laser plane of the profilometer is initially perpendicular to the calibration plane by manual observation. When adjusting the position of the laser line, the actuator is controlled to adjust the end pose of the actuator, thereby moving the profilometer so that the laser line falls on the calibration line and the endpoint of the laser line falls within the calibration plane to the maximum extent.

[0114] The beneficial effect of the above embodiments is that when the initial laser plane is perpendicular to the calibration plane, the laser will not have a large dispersion effect due to the oblique shooting. The laser line is relatively thinner and the optical cross-section is symmetrically distributed, making it easier to obtain the accurate laser line midpoint and reduce errors.

[0115] In another embodiment, a robotic arm is selected as the actuator. In step Sa2, the pose of the actuator's end effector is adjusted to move the line laser profiler, so that the plane containing the laser of the line laser profiler is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane containing the laser of the line laser profiler is parallel to the line perpendicular to the calibration line in the calibration plane. The following method is used:

[0116] Sa21 adjusts the position and orientation of the actuator end, causing the line laser profiler to move so that the laser line of the line laser profiler on the calibration plane falls on the calibration line, and the coordinates Q1 of the actuator end are recorded.

[0117] The Sa22 controller moves the linear laser profilometer along the calibration line to the preset position and records the coordinates Q2 at the end of the controller.

[0118] Sa23 controls the actuator to move the laser profilometer away from or near the calibration plane, keeping the laser line on the calibration line, and recording the coordinates Q3 of the actuator's end point;

[0119] The Sa24 three-point method is used to construct a third coordinate system, where Q1 is the origin. The X-axis is the axis of intersection with the x-axis. , The axis perpendicular to the plane is the Z-axis;

[0120] Sa25 obtains the angle between the Z-axis of the third coordinate system and the normal to the calibration plane, and controls the actuator to rotate around... Rotate the corresponding angle along the X-axis;

[0121] Sa26 controls the end of the actuator to translate, moving it along the normal direction of the calibration plane to position Q4, and observes the distance difference between the laser line and the calibration line; if the distance difference is greater than the threshold, the adjustment steps are repeated; if the distance difference is less than the threshold, the adjustment is completed so that the plane where the laser of the line laser profilometer is located is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line.

[0122] At this time, the normal of the plane in which the laser of the line laser profilometer is located is parallel to the line in the calibration plane that is perpendicular to the calibration line.

[0123] In a specific embodiment, in step Sc1, the blind zone shaping laser ray information corresponding to each blind zone is obtained through M blind zone information to form a blind zone shaping laser ray information set, using the following method:

[0124] For the j-th blind zone information, Sc11 calculates the parameters of the equation of the line containing the laser ray that forms the blind zone.

[0125] The coordinates of the laser point at the edge of the calibration block forming the blind zone are obtained by using the position information of the edge point of the calibration block forming the blind zone and the height difference with the calibration line. The coordinates of the laser endpoint at the edge of the blind zone are obtained by using the position information of the laser endpoint at the edge of the blind zone. The parameters of the equation information of the line where the laser ray forming the blind zone is located are obtained based on the two-point method.

[0126] Alternatively, the laser beam angle can be obtained by using the position information of the calibration block edge point forming the blind zone, the position information of the laser endpoint at the edge of the blind zone, and the height difference of the calibration line. The coordinates of the laser endpoint at the edge of the blind zone can be obtained by using the position information of the laser endpoint at the edge of the blind zone, and the parameters of the equation information of the line where the laser beam forming the blind zone is located can be obtained by using the coordinates of the laser endpoint at the edge of the blind zone and the laser beam angle.

[0127] Sc12 repeats step Sc11 to obtain the parameters of the linear equation information of the laser rays forming the blind zone in group M, and forms a set of laser ray information for blind zone formation.

[0128] In one specific embodiment, the Sc step, which obtains the origin of the line laser profilometer, also includes a Sc3 step: evaluating the error of the reprojection position information of the laser endpoint at the blind zone edge; the method used is as follows:

[0129] For each blind zone, the intersection of the line connecting the origin O of the line laser profilometer and the edge point of the calibration block forming the blind zone with the calibration plane is calculated using the position information of the calibration block edge point forming the blind zone. This yields the reprojection position information of the laser endpoint at the edge of the blind zone.

[0130] Calculate the reprojection position information of the laser endpoint at the edge of the blind zone and the reprojection error of the laser endpoint position at the edge of the blind zone;

[0131] Calculate the reprojection error of all blind areas, filter out points with excessive errors according to the preset threshold, and recalculate the origin O of the line laser profilometer after removing the corresponding points, or repeat steps Sc1-Sc2 to supplement new blind area information and recalculate and evaluate the origin of the line laser profilometer until the reprojection error is within the preset threshold range.

[0132] In one embodiment, the selected calibration block is a rectangular block; in step Sb2, the position of the calibration block is adjusted so that the calibration block forms a laser blind zone on the calibration plane. The method is as follows: adjust any side of the calibration block to be perpendicular to the laser line AB, and obtain the edge position information of the calibration block forming the blind zone by using the intersection point information of the rectangular block edge forming the laser blind zone and the calibration line and the height information of the calibration block.

[0133] In one embodiment, the direction of the calibration line is parallel to the X-axis or Y-axis direction of the calibration plane; in step Se1, the coordinate system transformation relationship H between the line laser profiler and the calibration plane is obtained by using the coordinates of the origin O of the line laser profiler, the direction of the laser angle bisector of the line laser profiler, the direction of the calibration line, and the preset coordinate axis direction of the line laser profiler. C This includes the following steps:

[0134] Obtain the angle β between the laser angle bisector of the line laser profilometer and the normal of the calibration plane;

[0135] The origin of the calibration plane coordinate system is translated to the origin O of the line laser profilometer to construct a third coordinate system. In the third coordinate system, the actuator is controlled to rotate by an angle β around an axis perpendicular to the calibration line in the calibration plane, so that the direction of the laser angle bisector of the line laser profilometer is perpendicular to the calibration plane. The axis perpendicular to the calibration line refers to the axis parallel to the normal of the plane where the laser of the line laser profilometer is located.

[0136] Based on the preset coordinate system of the line laser profilometer, the coordinate system transformation relationship H between the line laser profilometer and the calibration plane is obtained through the perpendicular relationship between the laser plane direction and the calibration line, the parallel relationship between the laser angle bisector direction of the line laser profilometer and the normal of the calibration plane, and the origin O of the line laser profilometer. C .

[0137] At this point, the coordinate axes of the line laser profilometer coordinate system have been manually adjusted to be either parallel or perpendicular to the coordinate axes of the calibration plane coordinate system, and the pose transformation matrix can be obtained directly by humans. By calculating this pose matrix with the current pose of the actuator end, the coordinate transformation matrix between the line laser profilometer and the actuator end can be obtained, which reduces the computational complexity and is more intuitive.

[0138] In one embodiment, the calibration line is provided with scale markings indicating distances for quickly obtaining blind spot information.

[0139] Compared with existing technologies, the method provided by this invention adjusts the position of the calibration block in the laser plane of the laser profilometer to form a blind zone of laser occlusion, thereby obtaining the calibration origin of the line laser profilometer, the orientation of the line laser angle bisector, and the pose relationship of the line laser profilometer in the calibration plane, and thus obtaining the coordinate system transformation matrix with the coordinate system of the actuator. This method uses readily available, conventionally shaped objects as calibration blocks, enabling rapid calibration even in scenarios without high-precision 3D calibration spheres or specially designed calibration objects. The method is simple and easy to operate. This method uses multiple rays within the laser projection range to calculate the intersection point, improving the stability and accuracy of the laser origin position; simultaneously, it avoids using data from the profilometer for feature calculations, reducing laser plane calibration errors caused by contour data errors, ensuring that the calibrated laser line accurately hits the target contour, which is helpful for subsequent measurements, safety checks, adaptive scan planning, and other operations. Furthermore, this method directly calibrates the physical spatial position of the laser plane using a coordinate system constructed from the laser plane normal, the laser angle bisector, and the laser emission point. This aligns better with the intuitive understanding of the line laser imaging plane in the principle of line laser profilometers, facilitating accurate control of the line laser profilometer's attitude and ensuring that the calibrated laser line profile is projected onto the target path according to the predetermined design. By calibrating the geometric shape information of the emitted laser and obtaining the physical origin and divergence angle of the laser plane, the positional relationship between the profilometer and the object can be adaptively adjusted according to sampling accuracy or time requirements, thereby adjusting the acquisition width of the laser profile on the target object.

[0140] Furthermore, it should be understood that the above embodiments only illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer, comprising an actuator, a line laser profilometer, a calibration plane, and a calibration block, wherein the line laser profilometer is rigidly connected to the end of the actuator via a mounting component; characterized in that, The calibration plane has a calibration line; when the calibration block is placed on the calibration plane, the contact area between the lower surface of the calibration block and the calibration plane is included in the projection area of ​​the upper surface of the calibration block onto the calibration plane; the coordinate system of the line laser profilometer is set according to the geometric characteristics of the laser plane of the line laser profilometer, the origin of the coordinate system of the line laser profilometer is the intersection point of the laser rays, the direction of the second coordinate axis is parallel to the normal of the plane where the laser is located, the direction of the third coordinate axis is parallel to the direction of the laser angle bisector, and the direction of the first coordinate axis is the cross product direction of the second and third coordinate axes; the hand-eye calibration method for improving the tracking and positioning accuracy of the line laser profilometer includes the following steps: Sa: The laser profilometer is perpendicular to the calibration plane, and the laser line falls on the calibration straight line. Sa1 is placed horizontally on the calibration plane; Sa2 adjusts the position of the end of the actuator, causing the line laser profiler to move so that the plane where the laser of the line laser profiler is located is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane where the laser of the line laser profiler is located is parallel to the line in the calibration plane that is perpendicular to the calibration line. Sa3 adjusts the end of the actuator to translate along the normal direction of the calibration plane, so that the two endpoints A and B of the laser line AB formed by the laser of the line laser profilometer and the calibration plane both fall on the calibration plane and within the preset area of ​​the calibration line; Sa4 records the pose Pose0 of the actuator end effector in the first coordinate system at this time; Sb collects blind zone information set for calibration. Sb1 places the calibration block within the laser line AB; Sb2 adjusts the position of the calibration block so that the calibration block forms a laser blind zone on the calibration plane, and records it as position i; Sb3 measures and records the K blind zone information formed by the laser of the line laser profilometer and the edge of the calibration block at position i, where K=1 or 2. The blind zone information includes the position information of the calibration block edge point forming the blind zone and the position information of the laser endpoint of the blind zone edge. The position information of the calibration block edge point forming the blind zone is the position information of the upper surface edge point of the calibration block forming the blind zone on the calibration line and the height difference between the upper surface edge point and the calibration line. The position information of the laser endpoint of the blind zone edge is the position information of the laser line endpoint near the blind zone on the calibration line. Sb4 Repeat steps Sb2 and Sb3, in which the calibration block moves N positions within the laser line AB, where N≥1, and obtains a total of M blind zone information, where M≥2; Sc obtains the origin of the line laser profilometer Sc1 obtains the blind zone shaping laser ray information corresponding to each blind zone through M blind zone information, forming a blind zone shaping laser ray information set; the blind zone shaping laser ray information is a parameter that can express the equation information of the line where the ray is located; Based on the set of blind zone forming laser ray information, Sc2 calculates the intersection of all blind zone forming laser rays to obtain the coordinate information of the origin O of the line laser profilometer in the calibration plane coordinate system; Sd obtains the direction of the laser angle bisector of the line laser profilometer. Sd1 obtains the left edge contour line OA of the laser based on the coordinate information of the origin O of the line laser profilometer and the endpoint A of the laser line AB. Sd2 obtains the right edge contour line OB of the laser based on the coordinate information of the origin O of the line laser profilometer and the endpoint B of the laser line AB. Sd3 calculates the angle bisector direction and included angle of the left edge contour line OA and the right edge contour line OB of the laser. Se obtains the coordinate system transformation relationship between the line laser profilometer and the end effector. Se1 obtains the coordinate system transformation relationship H between the line laser profilometer and the calibration plane using the coordinates of the origin O of the line laser profilometer, the direction of the laser angle bisector of the line laser profilometer, the direction of the calibration line, and the direction of the preset coordinate axes of the line laser profilometer. C The calibration line is parallel to the first coordinate axis of the line laser profilometer. Se2 calculates the coordinate system transformation relationship between the line laser profilometer and the end of the actuator by calibrating the transformation matrix between the planar coordinate system and the first coordinate system and the pose Pose0 of the actuator end in the first coordinate system.

2. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 1, characterized in that, In step Sa2, the pose of the end effector is adjusted to move the line laser profilometer, so that the plane containing the laser of the line laser profilometer is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane containing the laser of the line laser profilometer is parallel to a line in the calibration plane that is perpendicular to the calibration line, including: Sa21 constructs a second coordinate system with the calibration line, the calibration plane normal, and a point on the calibration line as the origin. The coordinate transformation matrix between the second coordinate system and the end of the actuator has been calibrated. Sa22 adjusts the position of the end of the actuator, causing the line laser profiler to move, so that the laser line of the line laser profiler on the calibration plane falls on the calibration line, which is denoted as position P1; Sa23 controls the end of the actuator to translate, moving it to position P2 along the normal direction of the calibration plane, and records the moving distance L and the distance d between the laser line and the calibration line; Sa24 estimates the angle between the plane containing the laser and the normal to the calibration plane as α = arctan(d / L); Sa25 controls the actuator to translate back to position P1; Sa26 controls the actuator to rotate around the axis containing the calibration line by an angle a degrees; Sa27 controls the end of the actuator to translate, moving it to position P3 along the normal direction of the calibration plane, and observes the distance difference between the laser line and the calibration line; if the distance difference is greater than the threshold, the adjustment steps are repeated; if the distance difference is less than the threshold, the adjustment is completed so that the plane where the laser of the line laser profilometer is located is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane in which the laser of the line laser profilometer is located is parallel to the straight line in the calibration plane that is perpendicular to the calibration line.

3. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 1, characterized in that, The actuator is a robotic arm. In step Sa2, the position and orientation of the end effector of the actuator are adjusted to move the line laser profilometer, so that the plane containing the laser of the line laser profilometer is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane containing the laser of the line laser profilometer is parallel to a line in the calibration plane that is perpendicular to the calibration line, including: Sa21 adjusts the position and orientation of the end of the actuator, drives the line laser profiler to move, so that the laser line of the line laser profiler on the calibration plane falls on the calibration line, and records the coordinates Q1 of the end of the actuator. Sa22 controls the actuator to move the line laser profilometer along the calibration line to a preset position, and records the coordinates Q2 of the end of the actuator; Sa23 controls the actuator to move the line laser profilometer away from or closer to the calibration plane, keeping the laser line on the calibration line, and records the coordinates Q3 of the actuator end point; The Sa24 three-point method is used to construct a third coordinate system, where Q1 is the origin. The X-axis is the axis of intersection with the x-axis. , The axis perpendicular to the plane is the Z-axis; Sa25 obtains the angle between the Z-axis of the third coordinate system and the normal to the calibration plane, and controls the actuator to rotate around... Rotate the corresponding angle along the X-axis; Sa26 controls the end of the actuator to translate, moving it to position Q4 along the normal direction of the calibration plane, and observes the distance difference between the laser line and the calibration line; if the distance difference is greater than the threshold, the adjustment steps are repeated; if the distance difference is less than the threshold, the adjustment is completed so that the plane where the laser of the line laser profilometer is located is perpendicular to the calibration plane and the laser line on the calibration plane falls on the calibration line. At this time, the normal of the plane in which the laser of the line laser profilometer is located is parallel to the line in the calibration plane that is perpendicular to the calibration line.

4. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 1, characterized in that, Step Sc1 obtains the blind zone shaping laser ray information corresponding to each of the M blind zone information, forming a blind zone shaping laser ray information set, including: For the j-th blind zone information, Sc11 calculates the parameters of the equation of the line containing the laser ray that forms the blind zone. The coordinates of the laser point at the edge of the calibration block forming the blind zone are obtained by using the position information of the edge point of the calibration block forming the blind zone and the height difference with the calibration line. The coordinates of the laser endpoint at the edge of the blind zone are obtained by using the position information of the laser endpoint at the edge of the blind zone. The parameters of the equation information of the line containing the laser ray forming the blind zone are obtained based on the two-point method. Alternatively, the laser ray angle is obtained by using the position information of the edge point of the calibration block forming the blind zone, the position information of the laser endpoint at the edge of the blind zone, and the height difference with the calibration line. The coordinates of the laser endpoint at the edge of the blind zone are obtained by using the position information of the laser endpoint at the edge of the blind zone. The parameters of the equation information of the line containing the laser ray forming the blind zone are obtained by using the coordinates of the laser endpoint at the edge of the blind zone and the laser ray angle. Sc12 repeats step Sc11 to obtain the parameters of the linear equation information of the laser rays forming the blind zone in group M, and forms a set of laser ray information for blind zone formation.

5. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 1, characterized in that, The Sc step, which obtains the origin of the line laser profilometer, also includes: Sc3, which evaluates the error of the reprojection position information of the laser endpoint at the edge of the blind zone. For each blind zone, the intersection of the line connecting the origin O of the line laser profilometer and the edge point of the calibration block forming the blind zone with the calibration plane is calculated using the position information of the edge point of the calibration block forming the blind zone, thereby obtaining the reprojection position information of the laser endpoint at the edge of the blind zone. Calculate the reprojection position information of the laser endpoint at the edge of the blind zone and the reprojection error of the laser endpoint position at the edge of the blind zone; Calculate the reprojection error of all blind areas, filter out points with excessive errors according to the preset threshold, and recalculate the origin O of the line laser profilometer after removing the corresponding points, or repeat steps Sc1-Sc2 to supplement new blind area information and recalculate and evaluate the origin of the line laser profilometer until the reprojection error is within the preset threshold range.

6. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 1, characterized in that, The calibration block is a rectangular block; in step Sb2, the position of the calibration block is adjusted so that the calibration block forms a laser blind zone on the calibration plane, including: adjusting any side of the calibration block to be perpendicular to the laser line AB, and obtaining the edge position information of the calibration block forming the blind zone by using the intersection point information of the rectangular block edge forming the laser blind zone and the calibration line and the height information of the calibration block.

7. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 1, characterized in that, The direction of the calibration line is parallel to the X-axis or Y-axis direction of the calibration plane.

8. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 7, characterized in that, In step Se1, the coordinate system transformation relationship H between the line laser profilometer and the calibration plane is obtained using the coordinates of the origin O of the line laser profilometer, the direction of the laser angle bisector of the line laser profilometer, the direction of the calibration line, and the direction of the preset coordinate axis of the line laser profilometer. C ,include: Obtain the angle β between the laser angle bisector of the line laser profilometer and the normal of the calibration plane; The origin of the calibration plane coordinate system is translated to the origin O of the line laser profilometer to construct a third coordinate system. In the third coordinate system, the actuator is controlled to rotate by an angle β around an axis perpendicular to the calibration line in the calibration plane, so that the direction of the laser angle bisector of the line laser profilometer is perpendicular to the calibration plane. Based on the preset coordinate system of the line laser profilometer, the coordinate system transformation relationship H between the line laser profilometer and the calibration plane is obtained through the perpendicular relationship between the laser plane direction and the calibration line, the parallel relationship between the laser angle bisector direction of the line laser profilometer and the normal of the calibration plane, and the origin O of the line laser profilometer. C .

9. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 1, characterized in that, The calibration line is marked with scale markings to indicate distances, which are used to quickly obtain information about the blind zone.

10. The hand-eye calibration method for improving the tracking and positioning accuracy of a line laser profilometer as described in claim 1, characterized in that, The first coordinate system is the actuator base coordinate system or the calibration plane coordinate system.

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