Automatic positioning and orienting laser scanning system and method

Abstract

The invention discloses an automatic positioning and orienting laser scanning system and method, and the system comprises a robot total station which has a long-distance communication function and is used for receiving a handbook device instruction, automatically searching a target prism, executing measurement, and converting measurement data into coordinates in an absolute coordinate system; the three-dimensional laser scanner comprises a WIFI communication module and is used for performing three-dimensional scanning on a to-be-measured target to generate point cloud data, and a 360-degree measuring prism is further arranged at the top of the three-dimensional laser scanner; and the handbook equipment comprises a WIFI communication module, and is used for controlling cooperative work of the robot total station and the three-dimensional laser scanner, and driving measurement instruction issuing and data receiving and analysis. According to the invention, high-efficiency three-dimensional laser scanning is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of laser measurement and point cloud generation applications, and in particular to an automatic positioning and orientation laser scanning system and method. Background Art

[0002] 3D laser scanners utilize the principle of laser ranging. By recording the 3D coordinates, reflectivity, and texture information of a large number of densely packed points on the surface of an object, they can rapidly reconstruct a 3D model of the object and various other graphical data, including lines, surfaces, and volumes. 3D laser scanning systems can acquire a large number of data points densely packed together. Therefore, compared to traditional single-point measurement, 3D laser scanning technology is considered a technological breakthrough, evolving from single-point measurement to surface measurement. 3D laser scanning technology has also found numerous applications in cultural heritage preservation, architecture, planning, civil engineering, factory renovation, interior design, building monitoring, traffic accident handling, legal evidence collection, disaster assessment, ship design, digital cities, and military analysis. A 3D laser scanning system consists of both data acquisition hardware and data processing software. Depending on the carrier, 3D laser scanning systems can be categorized as airborne, vehicle-mounted, ground-based, and handheld. The system consists of a laser transmitter, receiver, timer, motor-controlled rotatable filter, control circuit board, microcomputer, CCD camera, and software.

[0003] A total station, or electronic tachometer, automatically displays necessary observation data such as slope distance, zenith distance (vertical angle), and horizontal angle upon observation at the survey station. Horizontal distance, elevation difference, and coordinates of the point are also obtained almost instantly. Automated mapping can be achieved by connecting the data terminal used to collect data in the field with a computer or plotter via a transmission interface, along with data processing and mapping software. After decades of development, total stations have become highly mature and reliable. Currently, total stations have evolved into a new generation of intelligent measurement devices. These utilize a special camera capable of receiving highly reflective light and a motor mounted on the body of the total station, allowing the instrument to rotate horizontally and vertically. When the camera detects a high-reflectivity target that meets the specified requirements, it stops rotating and activates the measurement function to measure distance and angles, calculating the three-dimensional coordinates of the target using distance and angle.

[0004] In conventional stand-mounted scanner data processing, point cloud registration is commonly used. This registration method generally uses key point extraction methods such as PFP, PFHP, Span Image, and SHOT to extract feature points. The point clouds of the two stations are then registered through feature point matching and spatial rigid body invariance. The rotation and translation parameters between the two stations are calculated. However, point cloud registration has certain limitations. Because registration is performed based on feature points in the point cloud, in similar environments such as tunnels and indoor environments, the lack of or similar features can easily lead to mismatching of point clouds, resulting in registration failure. Therefore, when performing point cloud scanning in such advanced scenarios, the target ball splicing method is usually used. The specific method is: at each measuring station, more than three circular target balls are arranged in the direction of travel and in the opposite direction to ensure that more than six target balls can be identified and extracted in the point cloud of the measuring station; similarly, at the next measuring station, more than three circular target balls will be newly arranged in the direction of travel, while the target balls in the opposite direction will not be moved, and the same target balls and their positions in the previous station will be used to ensure that there are more than three target balls in the same position in the two adjacent stations. In this way, the two adjacent stations can be spliced ​​in a wire manner, but this solution requires frequent arrangement of target balls, which brings a certain amount of workload. At the same time, since the target balls have no coordinates, the point cloud after alignment is still a local coordinate system. Therefore, there are currently some solutions that use prism balls. In this way, the target balls mentioned above are replaced with special targets that are half prism and the other half target balls. Each target ball can be measured using a total station. Therefore, based on the coordinates of the three target balls, the point cloud data of one station can be converted from the relative coordinate system to the absolute coordinate system of the total station. However, in this case, the target balls need to be measured manually. Some solutions also try to use robotic total stations to measure the target balls. However, in some typical narrow areas, due to the increased distance between the target ball and the robotic total station, the robot will fail or stop searching for the prisms of the target ball due to the narrow field of view, and it will not be able to find all the prisms. Therefore, a better method is needed to work in this situation. The Chinese invention application with application number 201410118157.4 discloses "A three-dimensional laser scanner positioning device and a laser point cloud absolute positioning method". The device includes a three-dimensional laser scanner positioning base and two positioning prisms. The two positioning prisms are respectively arranged on both sides of the three-dimensional laser scanner positioning base through a positioning prism connecting rod, wherein the positioning prism connecting rod is fixed on the three-dimensional laser scanner positioning base, and the two positioning prisms are arranged at both ends of the positioning prism connecting rod through a screw connection. The method includes: step 10: fixing a 3D laser scanner on a 3D laser scanner positioning device, and collecting field data by combining the 3D laser scanner, the 3D laser scanner positioning device, and a total station to collect 3D point clouds and total station feature points of all measured objects; step 20: importing the field data collected in step 10 into a computer; step 30: a data calculation module in the computer calculates the absolute position coordinates of the 3D point cloud of the measured object based on the 3D point cloud of the measured object and the total station feature points, and outputs the calculated coordinates to an output module in the computer; and step 40: the output module in the computer outputs the positioned 3D laser point cloud data structure consistent with the total station control measurement coordinate system. The technical solution provided by this invention discloses a fixed prism positioning device and 7-parameter coordinate conversion, but does not address point cloud direction deviation and relies on manual measurement using a total station. Summary of the Invention

[0005] To address the technical problems of existing three-dimensional laser scanning systems, such as the large number of devices, high workflow complexity, slow search speed, and limited field of view, the present invention provides an automatic positioning and orientation laser scanning system and method. The technical solution adopted by the present invention is: A first aspect of the present invention provides a laser scanning system for automatic positioning and orientation, the system comprising: A robotic total station with long-distance communication capabilities is used to receive commands from a handheld device, automatically search for the target prism, perform measurements, and convert the measurement data into coordinates in an absolute coordinate system; A 3D laser scanner, including a Wi-Fi communication module, is used to perform 3D scanning of the target to be measured to generate point cloud data. A 360-degree measuring prism is also provided on the top of the 3D laser scanner. The handheld device, including a WIFI communication module, is used to control the collaborative work of the robotic total station and the 3D laser scanner, including driving the issuance of measurement instructions, data reception and analysis.

[0006] As a preferred solution, the system further includes a dedicated communication protocol module integrated into the handheld device, which is used to send the following instructions in sequence: First instruction: an instruction to drive the 3D laser scanner to rotate a preset angle; Second instruction: an instruction to drive the robotic total station to perform automatic target recognition; Repeat the first to second instructions at least four times to obtain multiple sets of 360-degree measurement prism coordinates and corresponding code disk angle values.

[0007] As a preferred solution, the handheld device calculates the absolute coordinates of the optical axis center of the three-dimensional laser scanner by fitting the coordinates of multiple measurement points of the 360-degree measurement prism.

[0008] As a preferred solution, the robotic total station further includes a built-in algorithm module for: Fit the rotation plane and optical axis center coordinates of the 3D laser scanner based on the coordinates of at least four 360-degree measurement prism measurement points and the corresponding code disk angle values; The rotation matrix of the point cloud data is calculated through the angle deviation of the code disk, and the relative coordinate system point cloud is converted into the absolute coordinate system point cloud.

[0009] A second aspect of the present invention provides a laser scanning method for automatic positioning and orientation, the method comprising: Set up and level the robotic total station, and determine the absolute coordinates and orientation of the total station by backsight orientation or resection method; Place the 3D laser scanner near the object to be measured and ensure that it has line of sight with the total station; Using a handheld device to send preset instructions to the robotic total station and 3D laser scanner through a dedicated protocol to perform measurements, obtaining multiple sets of data pairs, where the data pairs consist of the code table angle values ​​and the 360-degree measurement prism coordinates at the top of the scanner; Fitting the rotation plane of the three-dimensional laser scanner according to the data pair to calculate the coordinates of the center of the optical axis; The direction of the scanner station center is determined by the code disk angle deviation, and a rotation matrix is ​​generated; the relative coordinate system point cloud data collected by the scanner is converted to the absolute coordinate system by applying the rotation matrix and the station center coordinates.

[0010] As a preferred solution, the method of using a handheld device to send preset instructions to a robotic total station and a three-dimensional laser scanner through a dedicated protocol to perform measurement and obtain multiple sets of data pairs includes: a) Drive the 3D laser scanner to rotate an angle less than 60 degrees and record the current code disk angle value V; b) Drive the robot total station to measure the prism coordinate P at the top of the 3D laser scanner 360 degrees; c) Repeat a)-b) at least 4 times to generate multiple data pairs P1-V1, P2-V2, P3-V3, P4-V4, ..., P n -V n .

[0011] As a preferred solution, a method for fitting the rotation plane of the three-dimensional laser scanner and calculating the coordinates of the optical axis center according to the data pair includes: Data selection: Select the coordinates of the four 360-degree measuring prism measurement points and record them as P1 ( x 1, y 1, z 1), P2 ( x 2, y 2, z 2), P3 ( x 3. y 3. z 3) P4 ( x 4. y 4. z 4); Plane fitting: Select three 360-degree measuring prism measurement point coordinates to calculate the vector 、 , the cross product gives the normal vector ; Generate the initial plane equation based on the normal vector ; Calculate the distance from the fourth point P4 to the plane D , where; if the distance D If it is greater than the preset threshold, the least square method is used to optimize the plane equation; Circle center solution: Project the four points P1, P2, P3, and P4 onto the fitting plane and convert them into a two-dimensional point set to ; Solving circle equations , get the coordinates of the circle center ; According to the preset structural parameters of the three-dimensional laser scanner, the optical axis center offset is calculated; based on the calculated optical axis center offset, the three-dimensional coordinates of the optical axis center are calculated; wherein the preset structural parameters include the height h1 of the 360-degree measuring prism and the height h2 from the center of the scanner optical axis to the top of the scanner, and h1+h2 is the light output center offset.

[0012] As a preferred solution, the direction of the scanner station center is determined by the code disk angle deviation to generate a rotation matrix; the relative coordinate system point cloud data collected by the scanner is converted to the absolute coordinate system by applying the rotation matrix and the station center coordinates, including: According to the code disk angle values ​​V1, V2, V3, V4 and the normal vector of the fitting plane, calculate the angle between the code disk 0 degree scale and the absolute coordinate system XY plane dV ; According to the angle dVA rotation matrix is ​​obtained, and the rotation matrix is ​​converted into an absolute coordinate system after the point cloud is solved into a relative coordinate system.

[0013] As a preferred solution, the method of optimizing the plane equation using the least squares method includes: Assume the plane equation is:

[0014] Convert the plane equation to point form:

[0015] in, p 、 q 、 r All are parameters to be sought; For each data point ( x i , y i , z i ), and its vertical distance to the plane is:

[0016] Construct the objective function:

[0017] in, n Indicates the number of measurement points involved in plane fitting, i is the index number of the point; The objective function is used to minimize the sum of squared errors of all points.

[0018] The third aspect of the present invention provides a computer device, including a storage medium, a processor, and a computer program stored in the storage medium and executable by the processor. When the computer program is executed by the processor, the steps of the aforementioned automatic positioning and orientation laser scanning method are implemented.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention installs a 360-degree measurement prism and a multi-point fitting algorithm at any position, eliminating the need for physical alignment and significantly shortening the installation time.

[0020] The present invention automatically drives the scanner to rotate and fit the optical axis center through handheld software, replacing manual calibration, and is suitable for rapid station deployment in complex terrains (such as tunnels and mines).

[0021] The present invention calculates the rotation matrix through the code disk angle deviation (dV), eliminating the 180° direction reversal problem of the point cloud in feature-degraded scenes (such as tunnels), and greatly improving the stitching success rate.

[0022] The present invention significantly improves the accuracy of point cloud splicing by combining least squares plane fitting with structural parameter correction. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A connection diagram of an automatic positioning and orientation laser scanning system provided in this embodiment; Figure 2 A flow chart of an automatic positioning and orientation laser scanning method provided in this embodiment; Description of reference numerals: 1. Robotic total station; 2. 3D laser scanner; 21. 360-degree measuring prism; 3. Handheld device. DETAILED DESCRIPTION The accompanying drawings are for illustrative purposes only and are not to be construed as limiting the present invention; It should be clear that the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the embodiments of the present application.

[0024] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the embodiments of the present application. The singular forms "a," "the," and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0025] When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims. In the description of the present application, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0026] In addition, in the description of this application, unless otherwise specified, "plurality" refers to two or more. "And / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship. The present invention is further described below with reference to the accompanying drawings and examples.

[0027] The present invention is further described below with reference to the accompanying drawings and embodiments.

[0028] Example 1 Please refer to Figure 1 This embodiment provides an automatic positioning and orientation laser scanning system, the system comprising: A robotic total station 1, having a long-distance communication function, is used to receive instructions from a handheld device 3, automatically search for a target prism, perform measurements, and convert the measurement data into coordinates in an absolute coordinate system; A three-dimensional laser scanner 2, including a WIFI communication module, is used to perform three-dimensional scanning on the target to be measured to generate point cloud data. A 360-degree measuring prism 21 is also provided on the top of the three-dimensional laser scanner 2; The handheld device 3 includes a WIFI communication module, which is used to control the collaborative work of the robotic total station 1 and the three-dimensional laser scanner 2, including driving the issuance of measurement instructions, data reception and analysis.

[0029] In a specific embodiment, the system further includes a dedicated communication protocol module integrated in the handheld device 3, which is used to send the following instructions in sequence: The first instruction: the instruction _startScanRotate that drives the 3D laser scanner 2 to rotate the preset angle; The second instruction: the instruction _startATR that drives the robot total station 1 to execute automatic target recognition; Repeat the first instruction to the second instruction at least 4 times to obtain multiple sets of coordinates of the 360-degree measuring prism 21 and corresponding code disk angle values.

[0030] In a specific embodiment, the handheld device 3 calculates the absolute coordinates of the optical axis center of the three-dimensional laser scanner 2 by fitting the coordinates of multiple measurement points of the 360-degree measurement prism 21 .

[0031] In a specific embodiment, the robotic total station 1 further includes a built-in algorithm module for: Fitting the rotation plane and optical axis center coordinates of the 3D laser scanner 2 based on the coordinates of the measurement points of at least four 360-degree measurement prisms 21 and the corresponding code disk angle values; The rotation matrix of the point cloud data is calculated through the angle deviation of the code disk, and the relative coordinate system point cloud is converted into the absolute coordinate system point cloud.

[0032] Specifically, the general workflow of the system is as follows: 1. Set up and level the robotic total station 1. Whether it is aligned depends on whether the robotic total station 1 is set up on a known point.

[0033] 2. The robotic total station 1 is set up, and the coordinates and orientation of the current position of the robotic total station 1 are measured through backsight orientation or rear intersection.

[0034] 3. The 3D laser scanner 2 is positioned near the object to be scanned, and a line of sight is maintained between the 3D laser scanner 2 and the robot total station 1.

[0035] 4. The handheld device 3 is connected to the robotic total station 1 and the three-dimensional laser scanner 2 respectively.

[0036] 5. The handheld software drives the robotic total station 1 to observe the 360-degree measuring prism 21 on the top of the 3D laser scanner 2 and record the coordinates.

[0037] 6. The handheld software drives the 3D laser scanner 2 to perform scanning.

[0038] 7. The above is the scanning of one station. After the scanning is completed, the 3D laser scanner 2 moves to the next station and repeats steps 5-6 to perform measurement.

[0039] 8. When the distance between the 3D laser scanner 2 and the robotic total station 1 reaches a certain distance, or when there is no longer line of sight, the robotic total station 1 needs to be moved, and steps 1-6 need to be repeated.

[0040] Example 2 Please refer to Figure 2 This embodiment provides a laser scanning method for automatic positioning and orientation, the method comprising: S1: Set up the robotic total station and level it, and determine the absolute coordinates and orientation of the total station by backsight orientation or resection method; S2: Place the 3D laser scanner near the object to be measured, ensuring that it has line of sight with the total station; S3: Using a handheld device to send preset instructions to the robotic total station and 3D laser scanner through a dedicated protocol to perform measurements, obtaining multiple sets of data pairs, where the data pairs consist of the angle values ​​of the code table and the coordinates of the 360-degree measuring prism on the top of the scanner; In a specific embodiment, the method of using a handheld device to send preset instructions to a robotic total station and a three-dimensional laser scanner through a dedicated protocol to perform measurement and obtain multiple sets of data pairs includes: a) Drive the 3D laser scanner to rotate an angle less than 60 degrees and record the current code disk angle value V; b) Drive the robotic total station to measure the coordinate P of the prism on top of the 3D laser scanner 360 degrees; c) Repeat a)-b) at least 4 times to generate multiple data pairs P1-V1, P2-V2, P3-V3, P4-V4, ..., P n -V n .

[0041] S4: fitting the rotation plane of the three-dimensional laser scanner according to the data pair, and calculating the coordinates of the center of the optical axis; In a specific embodiment, a method for fitting the rotation plane of the three-dimensional laser scanner and calculating the coordinates of the center of the optical axis according to the data pair includes: Data selection: Select the coordinates of the measuring points of the four 360-degree measuring prisms and record them as P1 ( x 1, y 1, z 1), P2 ( x 2, y 2, z 2), P3 ( x 3. y 3. z 3) P4 ( x 4. y 4. z 4); Plane fitting: Select three 360-degree measuring prisms to calculate the coordinates of the measuring points 、 , the cross product gives the normal vector ; Generate the initial plane equation based on the normal vector ; Calculate the distance from the fourth point P4 to the plane D , where; if the distance D If it is greater than the preset threshold, the least square method is used to optimize the plane equation; Circle center solution: Project the four points P1, P2, P3, and P4 onto the fitting plane and convert them into a two-dimensional point set to ; Solving circle equations , get the coordinates of the circle center ; According to the preset structural parameters of the three-dimensional laser scanner, the optical axis center offset is calculated; based on the calculated optical axis center offset, the three-dimensional coordinates of the optical axis center are calculated; wherein the preset structural parameters include the height h1 of the 360-degree measuring prism and the height h2 from the center of the scanner optical axis to the top of the scanner, and h1+h2 is the light output center offset.

[0042] In a specific embodiment, the method of optimizing the plane equation using the least squares method includes: Assume the plane equation is:

[0043] Convert the plane equation to point form:

[0044] in, p 、 q 、 r All are parameters to be sought; For each data point ( x i , y i , z i ), and its vertical distance to the plane is:

[0045] Construct the objective function:

[0046] in, n Indicates the number of measurement points involved in plane fitting, i is the index number of the point; The objective function is used to minimize the sum of squared errors of all points.

[0047] S5: Determine the scanner station center direction through the code disk angle deviation and generate a rotation matrix; convert the relative coordinate system point cloud data collected by the scanner into an absolute coordinate system by applying the rotation matrix and the station center coordinates; In a specific embodiment, the method of determining the scanner station center direction by the code disk angle deviation and generating a rotation matrix; applying the rotation matrix and the station center coordinates to convert the relative coordinate system point cloud data collected by the scanner to the absolute coordinate system includes: According to the code disk angle values ​​V1, V2, V3, V4 and the normal vector of the fitting plane, calculate the angle between the code disk 0 degree scale and the absolute coordinate system XY plane dV , specifically: Calculate the vector from the center of the circle to the measured point: Given the coordinates of the fitting circle center P0 and four measurement points P1, P2, P3, and P4, calculate the vector:

[0048] in, i =1,2,3,4.

[0049] Compute the angle between adjacent vectors: vector and Angle Equal to the difference in code disk angles:

[0050] in, and are adjacent vectors, j =1,2,3,4, and i ≠ j ; V i , V j The code disk angle value returned by the scanner.

[0051] Construct a local coordinate system: X-axis (unit vector ): Pick Directions:

[0052] Y axis (unit vector ): calculate exist Projection onto a vertical plane:

[0053] Unitization:

[0054] Calculate the angle of the code disk 0 degree direction in the local coordinate system: The vector corresponding to the 0 degree direction of the code disk The coordinates in the local coordinate system are:

[0055] in ϕ is the angle to be determined.

[0056] According to the geometric relationship: when the code disk angle V = 0, its direction is the same as The angle is V 1 (i.e. ϕ =− V1).

[0057] Solving for angular deviation dV : dV It is the angle between the 0 degree direction of the code disk and the X axis of the absolute coordinate system, and is calculated by the following steps: Extract the absolute coordinate system reference direction: Take the absolute coordinate system X-axis unit vector ; Project onto the fitting plane: Will Projected onto the fitting plane (normal vector is ):

[0058] Calculate the angle of the projected vector in the local coordinate system:

[0059] Final angular deviation:

[0060] According to the angle dV A rotation matrix is ​​obtained, and the rotation matrix is ​​converted into an absolute coordinate system after the point cloud is solved into a relative coordinate system.

[0061] Example 3 This embodiment provides a computer device, including a storage medium, a processor, and a computer program stored in the storage medium and executable by the processor. When the computer program is executed by the processor, the steps of the automatic positioning and orientation laser scanning method described in Example 2 are implemented.

[0062] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A laser scanning system with automatic positioning and orientation, characterized in that: The system comprises: A robotic total station (1) having a long-distance communication function for receiving instructions from a handheld device, automatically searching for a target prism, performing measurements, and converting measurement data into coordinates in an absolute coordinate system; A three-dimensional laser scanner (2) comprising a WIFI communication module for performing three-dimensional scanning on a target to be measured to generate point cloud data, wherein a 360-degree measuring prism (21) is also provided on the top of the three-dimensional laser scanner (2); The handheld device (3) includes a WIFI communication module, which is used to control the collaborative work of the robot total station (1) and the three-dimensional laser scanner (2), including driving the measurement instruction issuance, data reception and analysis.

2. The automatic positioning and orientation laser scanning system according to claim 1, characterized in that: The system further comprises a dedicated communication protocol module integrated in the handheld device (3) for sending the following instructions in sequence: First instruction: an instruction for driving the three-dimensional laser scanner (2) to rotate a preset angle; Second instruction: an instruction to drive the robotic total station (1) to perform automatic target recognition; Repeat the first to second instructions at least four times to obtain multiple sets of 360-degree measurement prism coordinates and corresponding code disk angle values.

3. The automatic positioning and orientation laser scanning system according to claim 2, characterized in that: The handheld device (3) calculates the absolute coordinates of the optical axis center of the three-dimensional laser scanner (2) by fitting the coordinates of multiple measurement points of the 360-degree measurement prism (21).

4. The automatic positioning and orientation laser scanning system according to claim 3, characterized in that: The robotic total station (1) further includes a built-in algorithm module for: Fitting the rotation plane and optical axis center coordinates of the three-dimensional laser scanner (2) based on the coordinates of the measurement points of at least four 360-degree measurement prisms (21) and the corresponding code disk angle values; The rotation matrix of the point cloud data is calculated through the angle deviation of the code disk, and the relative coordinate system point cloud is converted into the absolute coordinate system point cloud.

5. A laser scanning method for automatic positioning and orientation, characterized in that: The method comprises: Set up and level the robotic total station, and determine the absolute coordinates and orientation of the robotic total station by backsight orientation or resection method; Place the 3D laser scanner near the object to be measured, ensuring that it has line of sight with the robotic total station; Using a handheld device to send preset instructions to the robotic total station and 3D laser scanner through a dedicated protocol to perform measurements, obtaining multiple sets of data pairs, where the data pairs consist of the code table angle values ​​and the coordinates of the 360-degree measuring prism on top of the scanner; Fitting the rotation plane of the three-dimensional laser scanner according to the data pair to calculate the coordinates of the center of the optical axis; The center direction of the 3D laser scanner is determined by the angle deviation of the code disk, and a rotation matrix is ​​generated; the relative coordinate system point cloud data collected by the 3D laser scanner is converted to the absolute coordinate system by applying the rotation matrix and the center coordinates.

6. The automatic positioning and orientation laser scanning method according to claim 5, characterized in that: The method of using a handheld device to send preset instructions to a robotic total station and a three-dimensional laser scanner through a dedicated protocol to perform measurement and obtain multiple sets of data pairs includes: a) Drive the 3D laser scanner to rotate an angle less than 60 degrees and record the current code disk angle value V; b) Drive the robotic total station to measure the coordinate P of the prism on top of the 3D laser scanner 360 degrees; c) Repeat a)-b) at least 4 times to generate multiple data pairs P1-V1, P2-V2, P3-V3, P4-V4, ..., P n -V n .

7. The automatic positioning and orientation laser scanning method according to claim 6, characterized in that: The method of fitting the rotation plane of the three-dimensional laser scanner and calculating the coordinates of the center of the optical axis according to the data pair includes: Data selection: Select the coordinates of the measuring points of the four 360-degree measuring prisms and record them as P1 ( x 1, y 1, z 1), P2 ( x 2, y 2, z 2), P3 ( x 3. y 3. z 3) P4 ( x 4. y 4. z 4); Plane fitting: Select three 360-degree measuring prisms to calculate the coordinates of the measuring points 、 , the cross product gives the normal vector ; Generate the initial plane equation based on the normal vector ; Calculate the distance from the fourth point P4 to the plane D , where; if the distance D If it is greater than the preset threshold, the least squares method is used to optimize the plane equation; Circle center solution: Project the four points P1, P2, P3, and P4 onto the fitting plane and convert them into a two-dimensional point set to ; Solving circle equations , get the center coordinates P0= ; According to the preset structural parameters of the three-dimensional laser scanner, the optical axis center offset is calculated; based on the calculated optical axis center offset, the three-dimensional coordinates of the optical axis center are calculated; wherein the preset structural parameters include the height h1 of the 360-degree measuring prism and the height h2 from the center of the scanner optical axis to the top of the scanner, and h1+h2 is the light output center offset.

8. The automatic positioning and orientation laser scanning method according to claim 7, characterized in that: The scanner station center direction is determined by the code disk angle deviation and a rotation matrix is ​​generated; The method of converting the relative coordinate system point cloud data collected by the scanner into the absolute coordinate system by applying the rotation matrix and the station center coordinates includes: According to the code disk angle values ​​V1, V2, V3, V4 and the normal vector of the fitting plane, calculate the angle between the code disk 0 degree scale and the absolute coordinate system XY plane dV ; According to the angle dV A rotation matrix is ​​obtained, and the rotation matrix is ​​converted into an absolute coordinate system after the point cloud is solved into a relative coordinate system.

9. The automatic positioning and orientation laser scanning method according to claim 7, characterized in that: The method for optimizing the plane equation using the least squares method comprises: Assume the plane equation is: Convert the plane equation to point form: in, p 、 q 、 r All are parameters to be sought; For each data point ( x i , y i , z i ), and its vertical distance to the plane is: Construct the objective function: in, n Indicates the number of measurement points involved in plane fitting, i is the index number of the point; The objective function is used to minimize the sum of squared errors of all points.

10. A computer device, characterized in that: The method comprises a storage medium, a processor, and a computer program stored in the storage medium and executable by the processor, wherein when the computer program is executed by the processor, the steps of the automatic positioning and orientation laser scanning method as described in any one of claims 5 to 9 are implemented.

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