Laser radar calibration device and calibration method for architectural design

Abstract

The invention relates to the technical field of laser detection, in particular to a laser radar calibration device and method for building design, the laser radar calibration device comprises a cylindrical base station, a laser radar is arranged in the middle of the base station, the number of calibration plates is N, and the N calibration plates are uniformly distributed on the peripheral wall of the base station in the circumferential direction, the calibration plates can be rotatably arranged on the base station and have a corresponding first working state and a second working state before and after rotation, and when the calibration plates are in the first working state, the distances between the N calibration plates and the laser radar are equal or continuously changed; in the second working state, laser beams emitted by the laser radar are reflected by the at least two calibration plates and then return to the laser radar; the laser radar calibration method comprises the step of calibrating the laser radar by adopting the first or second working mode according to different conditions, so that the laser radar can obtain multiple groups of measurement data in single measurement, the calibration time of the laser radar is shortened, and the calibration efficiency of the laser radar is improved.

Description

Technical Field

[0001] The present invention relates to the field of laser detection technology, and in particular to a laser radar calibration device and a calibration method for architectural design. Background Art

[0002] LiDAR is a radar system that uses laser beams to detect the position, speed and other characteristic quantities of a target. Its working principle is to first emit a detection laser beam to the target, then compare the received signal reflected from the target with the transmitted signal, and obtain relevant information about the target after appropriate processing.

[0003] Traditional LiDAR calibration methods are usually carried out in an open, enclosed room with no electromagnetic interference and few foreign objects. During the specific operation, the same detection plate needs to be placed at different distances from the LiDAR to be calibrated. The LiDAR detects the detection plate and collects detection data. This data is then analyzed and processed, and the relevant parameters of the laser transmitter are adjusted based on the processing results to complete the calibration of the LiDAR. However, in actual operation, the movement of detection plates between different distances often relies on manual handling or AGV transportation. This method has obvious defects: manual operation is prone to inaccurate placement of the detection plate due to operational errors, fatigue, and other factors. AGVs may also fail to place the detection plate in the ideal calibration position due to path planning errors, operational stability, and other issues, ultimately resulting in a significant reduction in calibration accuracy. At the same time, the detection plate is frequently moved and repositioned between different distances, which greatly increases the time cost of the entire calibration process and leads to low calibration efficiency.

[0004] To improve the accuracy and efficiency of lidar calibration, Chinese patent CN109001713B discloses a ranging accuracy calibration system. During the calibration process of the lidar, the vertical position of the lidar and the reflector is kept fixed, eliminating the need to repeatedly move the reflector in the direction of the lidar's transmission light path. Rapid calibration of the lidar's ranging is achieved by changing the reflector's receiving area.

[0005] However, the above-mentioned ranging accuracy calibration system also has some problems in actual use: it can only obtain one set of data at a time, and lacks other data for comparison and verification, making it difficult to ensure the credibility of the data. It is easy to cover up measurement errors caused by individual differences in equipment, accidental environmental factors, etc., thereby affecting the calibration efficiency and final calibration accuracy of the lidar. Summary of the Invention

[0006] Based on this, it is necessary to provide a laser radar calibration device and calibration method for architectural design to address the problems of low efficiency and poor accuracy in the current laser radar calibration process.

[0007] The above purpose is achieved through the following technical solutions: A laser radar calibration device for architectural design, comprising: A cylindrical base, on top of which the laser radar is coaxially arranged and capable of rotating around its own axis when in use; Calibration plates, the number of which is N, which are uniformly distributed on the outer peripheral wall of the base along the circumferential direction, each of which is set at the same height as the laser radar, and each of which is capable of sliding along the radial direction of the base, and the calibration plates are used to reflect the laser beam emitted by the laser radar to the laser radar, so that the laser radar measures the laser beam and obtains measurement parameters; The calibration plate can be rotatably arranged on the base along a first axis and has corresponding first and second working states before and after rotation. The first axis and the axis of the base are arranged in parallel. Before rotation, the reflective surface of the calibration plate and the laser beam emitted by the laser radar are arranged vertically. The calibration plate is in the first working state, and the calibration distances between N calibration plates and the laser radar are equal or the distances between N calibration plates and the laser radar continuously change to the calibration distance; after rotation, the calibration plate is in the second working state, and the laser beam emitted by the laser radar is reflected by at least two calibration plates and returns to the laser radar.

[0008] Furthermore, the measurement parameters include at least the flight time of the laser beam.

[0009] Furthermore, the laser radar calibration device for architectural design also includes a driving member, which is used to provide a driving force for the calibration plate to slide along the radial direction of the base.

[0010] The present invention also provides a laser radar calibration method for architectural design, which uses a laser radar calibration device for architectural design, wherein the radius of the base is r; the distance between the calibration plate and the outer peripheral wall of the base is S, and the minimum value of S is , the maximum value of S is , then the minimum distance between the calibration plate and the laser radar is , the maximum distance is ; The calibration distance between the calibration plate and the laser radar is The laser radar calibration method for architectural design comprises the following steps: Step S100, determining whether a first relational expression is established, wherein the first relational expression is: ; Step S200: When the first relational expression is established, it is determined whether the second relational expression is established. The second relational expression is ; Step S300: If established, calibrate the laser radar according to the first working mode; Step S400: If not established, calibrate the laser radar according to the second working mode.

[0011] Furthermore, in the first working mode, the distance between each calibration plate and the laser radar is the calibration distance , follow these steps: Step S310, the laser radar emits a laser beam while rotating; Step S320, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Step S330: After the laser radar rotates a preset number of times, the laser radar is calibrated.

[0012] Furthermore, in the first working mode, the distance between the N calibration plates and the laser radar is continuously changed to a calibration distance When the calibration plate slides along the radial direction of the base once, the distance is set to ; Initially, the distance between the first calibration plate and the laser radar is , along the same circumferential direction of the base, the distance between the i-th calibration plate and the laser radar is , i = 1, 2 to N; and follow the steps below: Step S340: the laser radar emits a laser beam while rotating, and when the laser radar scans the i-th calibration plate again, the i-th calibration plate slides along the radial direction of the base away from the axis of the base for a distance of , i=1, 2 to N; Step S350, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Step S360, when , calibrate the laser radar.

[0013] Furthermore, in the second working mode, the distance between each calibration plate and the laser radar is the calibration distance When the distance between the first calibration plate and the laser radar is set to , the distance between the qth calibration plate and the laser radar is , the distance between the first calibration plate and the qth calibration plate is , the central angle formed by the first calibration plate and the qth calibration plate is the largest, and the central angle is , Initially, the distances between all the calibration plates and the laser radar are ,but , , and follow these steps: Step S410, when hour, Calculate the angle ; Step S420, calculate the angle ; Step S430, when When the qth calibration plate slides along the radial direction of the base ,at this time , at this time the distance between the qth calibration plate and the laser radar is , , is the distance between the first calibration plate and the qth calibration plate at this time, and , calculate angle A and angle B; Step S431, adjusting the angles between the reflective surfaces of all the calibration plates and the laser beams emitted by the laser radar according to angle A and angle B; Step S440, the laser radar emits a laser beam while rotating; Step S441, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Step S442: After the laser radar rotates a preset number of times, the laser radar is calibrated.

[0014] Furthermore, the radius of the laser radar is After step S410, the method further includes: Step S411, calculate the vertical distance between the laser radar and the line connecting the first calibration plate and the qth calibration plate ; Step S412, when Calculate the angle ; Step S413, when When the central angle formed by the first calibration plate and the (q-1)th calibration plate is , , the distance between the first calibration plate and the laser radar , the distance between the q-1th calibration plate and the laser radar , the distance between the first calibration plate and the q-1th calibration plate , execute steps S410 to S442.

[0015] Furthermore, in the second working mode, the distance between the N calibration plates and the laser radar is continuously changed to a calibration distance When the calibration plate slides along the radial direction of the base once, the distance is set to ; Initially, the distance between all the calibration plates and the laser radar is , the distance between the first calibration plate and the laser radar is , the distance between the qth calibration plate and the laser radar is , the distance between the first calibration plate and the qth calibration plate is , the central angle formed by the first calibration plate and the qth calibration plate is the largest, and the central angle is , Initially, the distances between all the calibration plates and the laser radar are ,but , , and follow these steps: Step S450, when hour, Calculate the angle ; Step S460, calculate the angle ; Step S470, when When the first calibration plate slides along the radial direction of the base ,at this time , , is the distance between the first calibration plate and the qth calibration plate at this time, and , calculate angle A and angle B; Step S471, adjusting the angles between the reflective surfaces of all the calibration plates and the laser beams emitted by the laser radar according to angle A and angle B; Step S480, the laser radar emits a laser beam while rotating; and when the laser radar scans the i-th calibration plate again, the i-th calibration plate slides along the radial direction of the base away from the axis of the base for a distance of , i=1, 2 to N; Step S481, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Step S482, when , calibrate the laser radar.

[0016] Furthermore, the calibration method of the laser radar includes calculating the difference between the flight time of the laser beam after being reflected by each calibration plate and returning to the laser radar and the corresponding theoretical flight time, and calibrating the laser radar based on the difference.

[0017] The beneficial effects of the present invention are: The present invention relates to a laser radar calibration device and a calibration method for architectural design. In the process of calibrating the laser radar, when the calibration distance is short, the calibration plate is in a first working state. When the distances between N calibration plates and the laser radar are equal, the laser radar can obtain N sets of measurement data after one rotation. Under the premise that the distance between the calibration plate and the laser radar remains unchanged, the N sets of data can be compared with each other with high reliability, thereby shortening the laser radar calibration time and improving the laser radar calibration efficiency. When the distances between the N calibration plates and the laser radar continuously change, the laser radar can obtain N sets of continuously changing measurement data after one rotation, thereby facilitating the calibration of laser radars at different distances. , thereby improving the calibration accuracy of the laser radar while truly simulating the usage conditions; when the calibration distance is far, the calibration plate is in the second working state, so that the laser beam emitted by the laser radar can be reflected by at least two calibration plates and then return to the laser radar, which increases the measurement distance while making the usage conditions more realistic, thereby helping to improve the calibration accuracy of the laser radar; the laser radar calibration method for architectural design includes, under the premise that the first relationship holds, when the second relationship holds, calibrating the laser radar according to the first working mode, and when the second relationship does not hold, calibrating the laser radar according to the second working mode, and then being able to adopt different working modes according to different situations, thereby helping to improve the applicability of the laser radar calibration method for architectural design. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the three-dimensional structure of a laser radar calibration device for architectural design provided by one embodiment of the present invention; Figure 2 When the number of calibration plates provided in one embodiment of the present invention is ten, the work of the laser radar calibration device for architectural design is simplified. Figure 1 ; Figure 3 When the number of calibration plates provided in one embodiment of the present invention is ten, the work of the laser radar calibration device for architectural design is simplified. Figure 2 ; Figure 4 When the number of calibration plates provided in one embodiment of the present invention is ten, the work of the laser radar calibration device for architectural design is simplified. Figure 3 ; Figure 5 A schematic flow chart of a laser radar calibration method for architectural design provided in one embodiment of the present invention.

[0019] in: 100, base; 101, cylinder; 200, laser radar; 201, transmitter; 202, receiver; 300. Bracket; 301. Calibration plate. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] The serial numbers assigned to components herein, such as "first," "second," etc., are used solely to distinguish the objects being described and do not convey any sequential or technical meaning. References to "connection" and "coupling" herein, unless otherwise specified, include both direct and indirect connections (couplings). In the description of the present invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like, indicating positions or relationships, are based on those shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the device or element referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention.

[0022] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0023] like Figure 1As shown, a laser radar calibration device for architectural design provided by an embodiment of the present invention is used to calibrate a laser radar 200; in this embodiment, the laser radar calibration device for architectural design is configured to include a cylindrical base 100, a laser radar 200 and a calibration plate 301, the shape of the laser radar 200 is configured to be cylindrical, and the laser radar 200 is coaxially arranged on the top of the base 100 when in use and can rotate around its own axis, a transmitter 201 and a receiver 202 are provided on the peripheral wall surface of the laser radar 200, the transmitter 201 and the receiver 202 are arranged at the same height, the transmitter 201 is used to emit a laser beam, and the receiver 202 is used to receive the laser beam and measure the laser beam to obtain measurement parameters; the number of calibration plates 301 is N, and the N calibration plates 301 are evenly distributed on the outer peripheral wall of the base 100 along the circumferential direction, and each calibration plate 301 is arranged at the same height as the transmitter 201, and each calibration plate 301 can Sliding along the radial direction of the base 100, the calibration plate 301 is used to reflect the laser beam emitted by the laser radar 200 to the laser radar 200, so that the laser radar 200 measures the laser beam and obtains the measurement parameters; the calibration plate 301 can be rotatably set on the base 100 about the first axis and has a corresponding first working state and a second working state before and after the rotation, and the first axis and the axis of the base 100 are arranged in parallel. Before the rotation, the reflective surface of the calibration plate 301 and the laser beam emitted by the laser radar 200 are arranged perpendicularly, the calibration plate 301 is in the first working state, and the calibration distances between the N calibration plates 301 and the laser radar 200 are equal or the distances between the N calibration plates 301 and the laser radar 200 continuously change to the calibration distance; after the rotation, the calibration plate 301 is in the second working state, and the laser beam emitted by the laser radar 200 is reflected by at least two calibration plates 301 and returns to the laser radar 200.

[0024] Taking the number of calibration plates 301 as ten as an example, during the calibration of the laser radar 200, when the calibration distance is short, the calibration plates 301 are in the first working state, and the reflective surfaces of the ten calibration plates 301 are perpendicular to the laser beam emitted by the laser radar 200. According to the needs, the distances between the ten calibration plates 301 and the laser radar 200 are adjusted to be equal and the calibration distance or the distances between the ten calibration plates 301 and the laser radar 200 are continuously changed to the calibration distance. When the distances between the ten calibration plates 301 and the laser radar 200 are adjusted to be equal, the distances between the ten calibration plates 301 and the laser radar 200 are adjusted to be equal. When the laser radar 200 is at the calibration distance, it emits a laser beam through the transmitter 201 while rotating. During the rotation of the laser radar 200, when the laser radar 200 rotates until the laser beam is perpendicular to the reflective surface of any calibration plate 301, the laser beam is reflected from the surface of the calibration plate 301 back to the laser radar 200. At the same time, the laser radar 200 receives the laser radar 200 through the receiver 202 and measures the laser beam to obtain the measurement parameters. After the laser radar 200 rotates one circle, the receiver 202 receives a total of ten sets of measurement parameters. , and under the premise that the distance between the calibration plate 301 and the laser radar 200 remains unchanged, the ten sets of data can be compared with each other with high credibility, thereby shortening the calibration time of the laser radar 200 and improving the calibration efficiency of the laser radar 200; when the distance between the ten calibration plates 301 and the laser radar 200 continuously changes to the calibration distance, the laser radar 200 rotates while emitting a laser beam through the transmitter 201. During the rotation of the laser radar 200, when the laser radar 200 rotates to the point where the laser beam intersects with the reflection of any one of the calibration plates 301, the laser radar 200 rotates to the point where the laser beam intersects with the reflection of any one of the calibration plates 301. When the surface is vertical, the laser beam is reflected from the surface of the calibration plate 301 back to the laser radar 200. At the same time, the laser radar 200 receives the laser radar 200 through the receiver 202 and measures the laser beam to obtain measurement parameters. When the laser radar 200 rotates until the distance between the calibration plate 301 and the laser radar 200 is the calibration distance, the receiver 202 receives a total of multiple sets of continuously changing measurement data, which helps to calibrate the laser radar 200 at different distances, thereby improving the calibration accuracy of the laser radar 200 while truly simulating the usage conditions.

[0025] When the calibration distance is far, the calibration plate 301 is in the second working state, so that the laser beam emitted by the laser radar 200 can be reflected by at least two calibration plates 301 and then return to the laser radar 200, thereby increasing the measurement distance and making the operating conditions more realistic, thereby helping to improve the calibration accuracy of the laser radar 200.

[0026] Specifically, in order to facilitate the connection between the calibration plate 301 and the base 100, N cylinder bodies 101 are evenly distributed on the outer peripheral wall of the base 100, and each cylinder body 101 is extended along the radial direction of the base 100. A bracket 300 can be slidably inserted in each cylinder body 101, and the bracket 300 is L-shaped. The bracket 300 has a horizontal section and a vertical section perpendicular to the horizontal section, wherein the horizontal section is inserted in the cylinder body 101, and the vertical section is arranged upward in the vertical direction and the end of the vertical section away from the horizontal section is arranged at the same height as the transmitter 201. The calibration plate 301 and the bracket 300 are arranged in a one-to-one correspondence, and the middle parts of the two ends of the calibration plate 301 in the vertical direction are hinged on the end of the vertical section away from the horizontal section. The first axis is the line connecting the middle parts of the two ends of the calibration plate 301 itself in the vertical direction, and the axis of rotation of the calibration plate 301 is arranged parallel to the axis of the base 100.

[0027] Specifically, in order to provide driving force for the rotation of the laser radar 200, a driving motor is arranged at the top center position of the base 100. The output shaft of the driving motor is arranged upward and a rotating disk is sleeved on it. A groove is provided on the top of the rotating disk, which is engaged with the bottom of the laser radar 200 to drive the laser radar 200 to rotate.

[0028] In some embodiments, the measurement parameters include at least the flight time of the laser beam; the flight time error can be obtained based on the flight time of the laser beam and the corresponding theoretical flight time, and the laser radar 200 can be calibrated based on the error.

[0029] In this embodiment, a multiple measurement method can be used to measure and obtain multiple flight time errors under a certain beam pulse time width; by subtracting the maximum and minimum values ​​of the flight time error under the same beam pulse time width, the jitter value of the flight time error under a certain beam pulse time width can be obtained, thereby obtaining the discreteness of the single-point measurement of the laser radar 200 to be measured under different beam pulse time widths, which is convenient for calibrating the laser radar 200.

[0030] In some embodiments, the laser radar calibration device for architectural design is configured to further include a driving member, which is used to provide a driving force for the calibration plate 301 to slide in the radial direction of the base 100; in this embodiment, the driving member is configured as a hydraulic cylinder or a pneumatic cylinder, which is used to fill or extract hydraulic oil or gas between the cylinder body 101 and the bracket 300 to drive the calibration plate 301 to slide in the radial direction of the base 100 through the bracket 300, thereby changing the distance between the calibration plate 301 and the laser radar 200; when in use, when the hydraulic cylinder or the pneumatic cylinder fills the hydraulic oil or gas between the cylinder body 101 and the bracket 300, the hydraulic or pneumatic cylinder is used to fill or extract hydraulic oil or gas between the cylinder body 101 and the bracket 300. Under the action of , the bracket 300 moves in the direction away from the base 100, and the bracket 300 synchronously drives the calibration plate 301 to move in the direction away from the base 100 to increase the distance between the calibration plate 301 and the laser radar 200; when the hydraulic cylinder or pneumatic cylinder extracts hydraulic oil or gas from between the cylinder body 101 and the bracket 300, the pressure outside the cylinder body 101 is greater than the pressure inside the cylinder body 101. Under the action of the pressure difference between the inside and outside of the cylinder body 101, the bracket 300 moves in the direction close to the base 100, and the bracket 300 synchronously drives the calibration plate 301 to move in the direction close to the base 100 to reduce the distance between the calibration plate 301 and the laser radar 200.

[0031] In other embodiments, the driving member can also be set as an electric cylinder, which is set inside the cylinder body 101 to provide a driving force for the calibration plate 301 to slide along the radial direction of the base 100. The end of the electric cylinder away from the output shaft is fixedly connected to the inside of the end of the cylinder body 101 close to the base 100 by bolts. The output shaft of the electric cylinder extends along the radial direction of the base 100 and is fixedly connected to the end of the bracket 300 away from the calibration plate 301; when in use, when the output shaft of the electric cylinder is extended, it drives the bracket 300 to move away from the base 100, and the bracket 300 simultaneously drives the calibration plate 301 to move in the direction away from the base 100 to increase the distance between the calibration plate 301 and the laser radar 200. When the output shaft of the electric cylinder is retracted, it drives the bracket 300 to move toward the base 100, and the bracket 300 simultaneously drives the calibration plate 301 to move toward the base 100 to reduce the distance between the calibration plate 301 and the laser radar 200.

[0032] like Figure 5 As shown, an embodiment of the present invention further provides a laser radar calibration method for architectural design, using a laser radar calibration device for architectural design, setting the radius of the base to r, as shown in FIG. Figure 2 As shown, taking the number of calibration plates as ten as an example, the angle between adjacent calibration plates is The distance between the calibration plate and the outer wall of the base is S, and the minimum value of S is , the maximum value of S is , then the minimum distance between the calibration plate and the lidar is , the maximum distance is ; The calibration distance between the calibration plate and the lidar is The laser radar calibration method for architectural design includes the following steps: Step S100, determining whether a first relational expression is established, wherein the first relational expression is: ; Specifically, The closest test distance that can be measured by the laser radar calibration device for architectural design. is the maximum central angle of the calibration plate that can be refracted twice. When N is equal to ten, It is the farthest test distance at which the laser beam emitted by the laser radar can be reflected twice, which is obtained according to the law of cosines. When the first relationship is established, it means that the calibration distance between the calibration plate and the laser radar is within the test range of the laser radar calibration device for architectural design, and the laser radar calibration device for architectural design can calibrate the laser radar. When the first relationship is not established, it means that the calibration distance between the calibration plate and the laser radar is not within the test range of the laser radar calibration device for architectural design, and the laser radar calibration device for architectural design cannot calibrate the laser radar.

[0033] Step S200: When the first relational expression is established, it is determined whether the second relational expression is established. The second relational expression is ; Specifically, under the premise that the first relationship is established, it means that the calibration distance between the calibration plate and the laser radar is within the test range of the laser radar calibration device for architectural design, and the laser radar calibration device for architectural design can calibrate the laser radar. The size of determines the working mode of the laser radar calibration device for architectural design. The maximum test distance that the LiDAR calibration device for architectural design can measure in the first working mode.

[0034] Step S300: If established, calibrate the laser radar according to the first working mode; Specifically, when When established, it indicates that the laser radar calibration device for architectural design can calibrate the laser radar in the first working mode. The value of is small, so the lidar is calibrated according to the first working mode.

[0035] Step S400: If not established, calibrate the laser radar according to the second working mode.

[0036] Specifically, when If it is not true, it means that the laser radar calibration device for architectural design cannot calibrate the laser radar in the first working mode. The value of is large, so the lidar is calibrated according to the second working mode.

[0037] In a further embodiment, the first working mode is that the distance between each calibration plate and the laser radar is the calibration distance , follow these steps: Step S310, the laser radar emits a laser beam while rotating; Specifically, the bracket drives the calibration plate to move until the distance between the calibration plate and the laser radar is Then the laser radar rotates while emitting a laser beam through the transmitter. During the rotation of the laser radar, when the laser radar rotates until the laser beam is perpendicular to the reflective surface of any calibration plate, the laser beam is reflected from the surface of the calibration plate and returned to the laser radar.

[0038] Step S320, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Specifically, the laser radar receives the laser radar through a receiver and measures the laser beam to obtain the flight time of the laser beam.

[0039] Step S330: After the laser radar rotates a preset number of times, the laser radar is calibrated.

[0040] Specifically, after the laser radar rotates a preset number of circles, ten times the preset circle array measurement data is obtained. Under the premise that the distance between the calibration plate and the laser radar remains unchanged, the ten times the preset circle array measurement data can be compared with each other with high credibility. Calibrating the laser radar at this time helps to improve the calibration efficiency of the laser radar.

[0041] In other embodiments, the first working mode is to continuously change the distance between the N calibration plates and the laser radar to the calibration distance When the calibration plate slides along the radial direction of the base once, the distance is set to ; Initially, the distance between the first calibration plate and the lidar is , along the same circumferential direction of the base, the distance between the i-th calibration plate and the laser radar is , i = 1, 2 to N; Taking the number of calibration plates as ten as an example, the calibration plates are moved by the bracket so that the distance between the first calibration plate and the laser radar is , and along the clockwise direction of the base, the distance between the second calibration plate and the lidar is , the distance between the third calibration plate and the lidar is , the distance between the fourth calibration plate and the lidar is , the distance between the fifth calibration plate and the lidar is , the distance between the sixth calibration plate and the lidar is , the distance between the seventh calibration plate and the lidar is , the distance between the eighth calibration plate and the lidar is , the distance between the ninth calibration plate and the lidar is , the distance between the tenth calibration plate and the lidar is .

[0042] And follow these steps: Step S340: the laser radar emits a laser beam while rotating, and when the laser radar scans the i-th calibration plate again, the i-th calibration plate slides along the radial direction of the base away from the axis of the base for a distance of , i=1, 2 to N; Specifically, the calibration plate is driven to move by the bracket, and the laser radar rotates clockwise while emitting a laser beam through the transmitter. During the rotation of the laser radar, when the laser radar rotates until the laser beam is perpendicular to the reflective surface of any one of the calibration plates, the laser beam is reflected from the surface of the calibration plate back to the laser radar; and when the laser radar scans the i-th calibration plate again, the distance that the i-th calibration plate slides along the radial direction of the base toward the axial direction away from the base is Taking the first calibration plate as an example, when the laser radar scans the first calibration plate again, the distance the first calibration plate slides along the radial direction of the base toward the axis away from the base is , then the distance between the first calibration plate and the lidar is , so that the distance between the calibration plate and the lidar can change continuously.

[0043] Step S350, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Specifically, the laser radar receives the laser radar through a receiver and measures the laser beam to obtain the flight time of the laser beam.

[0044] Step S360, when , calibrate the laser radar.

[0045] Specifically, during the rotation of the laser radar, the distance between the corresponding scanned calibration plate and the laser radar changes accordingly. When , it means that the distance between the calibration plate and the laser radar is the calibration distance. At this time, the receiver receives multiple sets of continuously changing measurement data, thereby realizing a true simulation of the operating conditions. Calibrating the laser radar at this time helps to improve the calibration accuracy of the laser radar.

[0046] In other embodiments, the distance between each calibration plate and the laser radar in the second working mode is the calibration distance When , the distance between the first calibration plate and the lidar is set to , the distance between the qth calibration plate and the laser radar is , the distance between the first calibration plate and the qth calibration plate is , the central angle formed by the first calibration plate and the qth calibration plate is the largest, and the central angle is , , initially, the distance between all calibration plates and the lidar is ,but , according to the cosine theorem, we can get ; Take the number of calibration plates as ten as an example, Figure 2 As shown in the figure, the central angle formed by the first calibration plate and the fifth calibration plate in the counterclockwise direction is the largest. , and the distance between the first calibration plate and the lidar is , the distance between the fifth calibration plate and the laser radar in the counterclockwise direction is , the distance between the first calibration plate and the fifth calibration plate in the counterclockwise direction is ; Adjusting the distance between the ten calibration plates and the laser radar to be equal by the bracket, after step S400, further comprising: Step S410, when hour, Calculate the angle ; Specifically, when When , it means that the laser beam emitted by the laser radar passes through the first calibration plate and the fifth calibration plate in the counterclockwise direction. The distance traveled by the laser beam is the calibration distance At this time, the angle B between the line between the first calibration plate and the fifth calibration plate in the counterclockwise direction and the line between the fifth calibration plate and the lidar in the counterclockwise direction can be calculated according to the cosine theorem.

[0047] Step S420, calculate the angle ; Specifically, at this time, the angle A between the line connecting the first calibration plate and the fifth calibration plate in the counterclockwise direction and the line connecting the first calibration plate and the laser radar can be calculated according to the law of cosines.

[0048] Step S430, when When the qth calibration plate slides along the radial direction of the base ,at this time , at this time the distance between the qth calibration plate and the laser radar is , , is the distance between the first calibration plate and the qth calibration plate at this time, and , calculate angle A and angle B; Specifically, when When, such as Figure 3 As shown, the distance that the qth calibration plate slides along the radial direction of the base can be adjusted to increase The value of makes the laser beam emitted by the laser radar pass through the first calibration plate and the fifth calibration plate in the counterclockwise direction. The distance traveled by the laser beam is the calibration distance ; Set the distance that the qth calibration plate slides along the radial direction of the base ,at this time , = ,at this time , you can follow Calculate The value of , then can be followed according to The values ​​of angles A and B are calculated using the law of cosines.

[0049] Step S431, adjusting the angles between the reflective surfaces of all the calibration plates and the laser beams emitted by the laser radar according to angle A and angle B; Specifically, the angles between the reflective surfaces of the first calibration plate, the second calibration plate in the counterclockwise direction, the third calibration plate in the counterclockwise direction, and the fourth calibration plate in the counterclockwise direction and the laser beam emitted by the laser radar are adjusted according to the angle A, and the angles between the reflective surfaces of the fifth calibration plate in the counterclockwise direction, the sixth calibration plate in the counterclockwise direction, the seventh calibration plate in the counterclockwise direction, and the eighth calibration plate in the counterclockwise direction and the laser beam emitted by the laser radar are adjusted according to the angle B, so that the laser beam emitted by the laser radar can be reflected from the first calibration plate to the fifth calibration plate in the counterclockwise direction. The light passes through a calibration plate in the counterclockwise direction, then reflects off the fifth calibration plate in the counterclockwise direction and returns to the lidar; it passes through the second calibration plate in the counterclockwise direction and reflects off the sixth calibration plate in the counterclockwise direction, then reflects off the sixth calibration plate in the counterclockwise direction and returns to the lidar; it passes through the third calibration plate in the counterclockwise direction and reflects off the seventh calibration plate in the counterclockwise direction, then reflects off the seventh calibration plate in the counterclockwise direction and returns to the lidar; it passes through the fourth calibration plate in the counterclockwise direction and reflects off the eighth calibration plate in the counterclockwise direction, then reflects off the eighth calibration plate in the counterclockwise direction and returns to the lidar.

[0050] Step S440, the laser radar emits a laser beam while rotating; Specifically, the laser radar rotates while emitting a laser beam through the transmitter. During the rotation of the laser radar, when the laser radar rotates until the laser beam contacts the reflective surfaces of the first calibration plate, the second calibration plate in the counterclockwise direction, the third calibration plate in the counterclockwise direction, and the fourth calibration plate in the counterclockwise direction, it is reflected by them and reaches the reflective surface of the corresponding calibration plate, and then reflected by the reflective surface of the corresponding calibration plate and returns to the laser radar; when the laser radar rotates until the laser beam contacts the reflective surfaces of the fifth calibration plate in the counterclockwise direction, the sixth calibration plate in the counterclockwise direction, the seventh calibration plate in the counterclockwise direction, and the eighth calibration plate in the counterclockwise direction, it is reflected by them and reaches the reflective surface of the corresponding calibration plate, and then reflected by the reflective surface of the corresponding calibration plate and returns to the laser radar.

[0051] Step S441, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Specifically, the laser radar receives the laser radar through a receiver and measures the laser beam to obtain the flight time of the laser beam.

[0052] Step S442: After the laser radar rotates a preset number of times, the laser radar is calibrated.

[0053] Specifically, after the laser radar rotates a preset number of times, multiple sets of measurement data can be obtained. Under the premise that the distance between the calibration plate and the laser radar remains unchanged, the multiple sets of measurement data can be compared with each other with high credibility. Calibrating the laser radar at this time helps to improve the calibration efficiency of the laser radar.

[0054] In a further embodiment, the radius of the laser radar is set to After step S410, the method further includes: Step S411, calculate the vertical distance between the laser radar and the line connecting the first calibration plate and the qth calibration plate ; Specifically, since the laser radar itself has a size, in order to avoid the laser beam emitted by the laser radar being blocked by the laser radar itself, it is necessary to calculate the vertical distance from the laser radar to the line connecting the first calibration plate and the qth calibration plate, such as Figure 1 As shown, .

[0055] Step S412, when Calculate the angle ; Specifically, when When , it means that the laser beam emitted by the laser radar will not be blocked by the laser radar, and the angle can be calculated. .

[0056] Step S413, when When the central angle formed by the first calibration plate and the (q-1)th calibration plate is , , the distance between the first calibration plate and the laser radar , the distance between the q-1th calibration plate and the laser radar , the distance between the first calibration plate and the q-1th calibration plate , execute steps S410 to S442.

[0057] Specifically, when , it means that the laser beam emitted by the laser radar will be blocked by the laser radar. At this time, it is necessary to change the corresponding calibration plate to which the laser beam emitted by the laser radar is reflected after passing through the first calibration plate. For example, if the number of calibration plates is set to ten, Figure 4 As shown, the central angle formed by the first calibration plate and the fourth calibration plate in the counterclockwise direction is , the distance between the first calibration plate and the lidar , the distance between the q-1th calibration plate and the lidar , and the distance between the first calibration plate and the q-1th calibration plate can be obtained according to the cosine theorem , and then execute steps S410 to S442 to obtain multiple sets of measurement data.

[0058] In other embodiments, the second working mode is to continuously change the distance between the N calibration plates and the laser radar to the calibration distance When , the distance between the first calibration plate and the lidar is set to , the distance between the qth calibration plate and the laser radar is , the distance between the first calibration plate and the qth calibration plate is , the central angle formed by the first calibration plate and the qth calibration plate is the largest, and the central angle is , , initially, the distance between all calibration plates and the lidar is ,but , according to the cosine theorem, we can get ; Take the number of calibration plates as ten as an example, Figure 2 As shown in the figure, the central angle formed by the first calibration plate and the fifth calibration plate in the counterclockwise direction is the largest. , and the distance between the first calibration plate and the lidar is , the distance between the fifth calibration plate and the laser radar in the counterclockwise direction is , the distance between the first calibration plate and the fifth calibration plate in the counterclockwise direction is When the distance between the ten calibration plates and the laser radar is continuously changed by adjusting the bracket, the second working mode further includes the following steps: Step S450, when hour, Calculate the angle ; Specifically, when When , it means that the laser beam emitted by the laser radar passes through the first calibration plate and the fifth calibration plate in the counterclockwise direction. The distance the laser beam travels is At this time, the angle B between the line between the first calibration plate and the fifth calibration plate in the counterclockwise direction and the line between the fifth calibration plate and the lidar in the counterclockwise direction can be calculated according to the cosine theorem.

[0059] Step S460, calculate the angle ; Specifically, at this time, the angle A between the line connecting the first calibration plate and the fifth calibration plate in the counterclockwise direction and the line connecting the first calibration plate and the laser radar can be calculated according to the law of cosines.

[0060] Step S470, when When the first calibration plate slides along the radial direction of the base ,at this time , , is the distance between the first calibration plate and the qth calibration plate at this time, and , calculate angle A and angle B; Specifically, when At this time, the distance that the first calibration plate slides along the radial direction of the base can be adjusted to increase The value of makes the laser beam emitted by the laser radar pass through the first calibration plate and the fifth calibration plate in the counterclockwise direction. The distance the laser beam travels is , set the distance that the first calibration plate slides along the radial direction of the base ,at this time , = ,at this time , you can follow Calculate The value of , then can be followed according to The values ​​of angles A and B are calculated using the law of cosines.

[0061] Step S471, adjusting the angles between the reflective surfaces of all the calibration plates and the laser beams emitted by the laser radar according to angle A and angle B; Specifically, the angles between the reflective surfaces of the first calibration plate, the second calibration plate in the counterclockwise direction, the third calibration plate in the counterclockwise direction, and the fourth calibration plate in the counterclockwise direction and the laser beam emitted by the laser radar are adjusted according to the angle A, and the angles between the reflective surfaces of the fifth calibration plate in the counterclockwise direction, the sixth calibration plate in the counterclockwise direction, the seventh calibration plate in the counterclockwise direction, and the eighth calibration plate in the counterclockwise direction and the laser beam emitted by the laser radar are adjusted according to the angle B, so that the laser beam emitted by the laser radar can be reflected from the first calibration plate to the fifth calibration plate in the counterclockwise direction, and then to the fifth calibration plate in the counterclockwise direction. After being reflected from the first calibration plate, it returns to the laser radar, is reflected from the second calibration plate in the counterclockwise direction to the sixth calibration plate in the counterclockwise direction, and then is reflected from the sixth calibration plate in the counterclockwise direction and returns to the laser radar, is reflected from the third calibration plate in the counterclockwise direction to the seventh calibration plate in the counterclockwise direction, and then is reflected from the seventh calibration plate in the counterclockwise direction and returns to the laser radar, is reflected from the fourth calibration plate in the counterclockwise direction to the eighth calibration plate in the counterclockwise direction, and then is reflected from the eighth calibration plate in the counterclockwise direction and returns to the laser radar, and the distance traveled by the laser beam between the first calibration plate and the fifth calibration plate in the counterclockwise direction is The distance traveled between the second calibration plate in the counterclockwise direction and the sixth calibration plate in the counterclockwise direction is The distance traveled between the third calibration plate in the counterclockwise direction and the seventh calibration plate in the counterclockwise direction is The distance traveled between the fourth calibration plate in the counterclockwise direction and the eighth calibration plate in the counterclockwise direction is , and cycle in sequence.

[0062] Step S480, the laser radar emits a laser beam while rotating; and when the laser radar scans the i-th calibration plate again, the i-th calibration plate slides along the radial direction of the base away from the axis of the base for a distance of , i=1, 2 to N; Specifically, the calibration plate is driven to move by the bracket, and the laser radar rotates clockwise while emitting a laser beam through the transmitter. During the rotation of the laser radar, when the laser radar rotates until the laser beam contacts the reflective surfaces of the first calibration plate, the second calibration plate in the counterclockwise direction, the third calibration plate in the counterclockwise direction, and the fourth calibration plate in the counterclockwise direction, it is reflected by them and reaches the reflective surface of the corresponding calibration plate, and then reflected by the reflective surface of the corresponding calibration plate and returns to the laser radar; when the laser radar rotates until the laser beam contacts the reflective surfaces of the fifth calibration plate in the counterclockwise direction, the sixth calibration plate in the counterclockwise direction, the seventh calibration plate in the counterclockwise direction, and the eighth calibration plate in the counterclockwise direction, it is reflected by them and reaches the reflective surface of the corresponding calibration plate, and then reflected by the reflective surface of the corresponding calibration plate and returns to the laser radar.

[0063] And when the laser radar scans the i-th calibration plate again, the distance that the i-th calibration plate slides along the radial direction of the base toward the axis away from the base is , i = 1, 2 to N, taking the first calibration plate as an example, when the laser radar scans the first calibration plate again, the distance the first calibration plate slides along the radial direction of the base toward the axis away from the base is , then the distance between the first calibration plate and the lidar is , so that the distance between the calibration plate and the lidar can change continuously.

[0064] Step S481, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Specifically, the laser radar receives the laser radar through a receiver and measures the laser beam to obtain the flight time of the laser beam.

[0065] Step S482, when , calibrate the laser radar.

[0066] Specifically, during the rotation of the laser radar, the distance between the corresponding scanned calibration plate and the laser radar changes accordingly. When , it means that the distance between the calibration plate and the laser radar is the calibration distance. At this time, the receiver receives multiple sets of continuously changing measurement data, thereby realizing a true simulation of the operating conditions. Calibrating the laser radar at this time helps to improve the calibration accuracy of the laser radar.

[0067] In other embodiments, similarly, steps S411 to S413 may be executed to prevent the laser beam emitted by the laser radar from being blocked by the laser radar itself.

[0068] In a further embodiment, the laser radar is calibrated by calculating the difference between the flight time of the laser beam after being reflected by each calibration plate and returning to the laser radar and the corresponding theoretical flight time, and calibrating the laser radar based on the difference.

[0069] In this embodiment, a multiple measurement method can be used to measure and obtain multiple flight time errors under a certain beam pulse time width; by subtracting the maximum and minimum values ​​of the flight time error under the same beam pulse time width, the jitter value of the flight time error under a certain beam pulse time width can be obtained, thereby obtaining the discreteness of the single-point measurement of the laser radar to be measured under different beam pulse time widths, which is convenient for calibrating the laser radar.

[0070] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0071] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A laser radar calibration device for architectural design, characterized in that: The laser radar calibration device for architectural design includes: A cylindrical base, on top of which the laser radar is coaxially arranged and capable of rotating around its own axis when in use; Calibration plates, the number of which is N, which are uniformly distributed on the outer peripheral wall of the base along the circumferential direction, each of which is set at the same height as the laser radar, and each of which is capable of sliding along the radial direction of the base, and the calibration plates are used to reflect the laser beam emitted by the laser radar to the laser radar, so that the laser radar measures the laser beam and obtains measurement parameters; The calibration plate can be rotatably arranged on the base along a first axis and has corresponding first and second working states before and after rotation. The first axis and the axis of the base are arranged in parallel. Before rotation, the reflective surface of the calibration plate and the laser beam emitted by the laser radar are arranged vertically. The calibration plate is in the first working state, and the calibration distances between N calibration plates and the laser radar are equal or the distances between N calibration plates and the laser radar continuously change to the calibration distance; after rotation, the calibration plate is in the second working state, and the laser beam emitted by the laser radar is reflected by at least two calibration plates and returns to the laser radar.

2. The laser radar calibration device for architectural design according to claim 1, characterized in that: The measurement parameters include at least the flight time of the laser beam.

3. The laser radar calibration device for architectural design according to claim 1, characterized in that: The laser radar calibration device for architectural design further includes a driving member, which is used to provide a driving force for the calibration plate to slide along the radial direction of the base.

4. A laser radar calibration method for architectural design, characterized in that: The laser radar calibration device for architectural design according to claim 1 is used, wherein the radius of the base is r; the distance between the calibration plate and the outer peripheral wall of the base is S, and the minimum value of S is , the maximum value of S is , then the minimum distance between the calibration plate and the laser radar is , the maximum distance is ; The calibration distance between the calibration plate and the laser radar is The laser radar calibration method for architectural design comprises the following steps: Step S100, determining whether a first relational expression is established, wherein the first relational expression is: ; Step S200: When the first relational expression is established, it is determined whether the second relational expression is established. The second relational expression is ; Step S300: If established, calibrate the laser radar according to the first working mode; Step S400: If not established, calibrate the laser radar according to the second working mode.

5. The laser radar calibration method for architectural design according to claim 4, characterized in that: In the first working mode, the distance between each calibration plate and the laser radar is the calibration distance , follow these steps: Step S310, the laser radar emits a laser beam while rotating; Step S320, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Step S330: After the laser radar rotates a preset number of times, the laser radar is calibrated.

6. The laser radar calibration method for architectural design according to claim 4, characterized in that: In the first working mode, the distance between the N calibration plates and the laser radar is continuously changed to the calibration distance When the calibration plate slides along the radial direction of the base once, the distance is set to ; Initially, the distance between the first calibration plate and the laser radar is , along the same circumferential direction of the base, the distance between the i-th calibration plate and the laser radar is , i = 1, 2 to N; and follow the steps below: Step S340: the laser radar emits a laser beam while rotating, and when the laser radar scans the i-th calibration plate again, the i-th calibration plate slides along the radial direction of the base away from the axis of the base for a distance of , i=1, 2 to N; Step S350, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Step S360, when , calibrate the laser radar.

7. The laser radar calibration method for architectural design according to claim 4, characterized in that: In the second working mode, the distance between each calibration plate and the laser radar is the calibration distance When the distance between the first calibration plate and the laser radar is set to , the distance between the qth calibration plate and the laser radar is , the distance between the first calibration plate and the qth calibration plate is , the central angle formed by the first calibration plate and the qth calibration plate is the largest, and the central angle is , Initially, the distances between all the calibration plates and the laser radar are ,but , , and follow these steps: Step S410, when hour, Calculate the angle ; Step S420, calculate the angle ; Step S430, when When the qth calibration plate slides along the radial direction of the base ,at this time , at this time the distance between the qth calibration plate and the laser radar is , , is the distance between the first calibration plate and the qth calibration plate at this time, and , calculate angle A and angle B; Step S431, adjusting the angles between the reflective surfaces of all the calibration plates and the laser beams emitted by the laser radar according to angle A and angle B; Step S440, the laser radar emits a laser beam while rotating; Step S441, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Step S442: After the laser radar rotates a preset number of times, the laser radar is calibrated.

8. The laser radar calibration method for architectural design according to claim 7, characterized in that: The radius of the laser radar is ; After step S410, the method further includes: Step S411, calculate the vertical distance between the laser radar and the line connecting the first calibration plate and the qth calibration plate ; Step S412, when Calculate the angle ; Step S413, when When the central angle formed by the first calibration plate and the (q-1)th calibration plate is , , the distance between the first calibration plate and the laser radar , the distance between the q-1th calibration plate and the laser radar , the distance between the first calibration plate and the q-1th calibration plate , execute steps S410 to S442.

9. The laser radar calibration method for architectural design according to claim 4, characterized in that: In the second working mode, the distance between the N calibration plates and the laser radar is continuously changed to the calibration distance When the calibration plate slides along the radial direction of the base once, the distance is set to ; Initially, the distance between all the calibration plates and the laser radar is , the distance between the first calibration plate and the laser radar is , the distance between the qth calibration plate and the laser radar is , the distance between the first calibration plate and the qth calibration plate is , the central angle formed by the first calibration plate and the qth calibration plate is the largest, and the central angle is , Initially, the distances between all the calibration plates and the laser radar are ,but , , and follow these steps: Step S450, when hour, Calculate the angle ; Step S460, calculate the angle ; Step S470, when When the first calibration plate slides along the radial direction of the base ,at this time , , is the distance between the first calibration plate and the qth calibration plate at this time, and , calculate angle A and angle B; Step S471, adjusting the angles between the reflective surfaces of all the calibration plates and the laser beams emitted by the laser radar according to angle A and angle B; Step S480, the laser radar emits a laser beam while rotating; and when the laser radar scans the i-th calibration plate again, the i-th calibration plate slides along the radial direction of the base away from the axis of the base for a distance of , i=1, 2 to N; Step S481, recording the flight time of the laser beam emitted by the laser radar after being reflected by each of the calibration plates and returning to the laser radar; Step S482, when , calibrate the laser radar.

10. The laser radar calibration method for architectural design according to claim 9, characterized in that: The calibration method of the laser radar includes calculating the difference between the flight time of the laser beam after being reflected by each calibration plate and returning to the laser radar and the corresponding theoretical flight time, and calibrating the laser radar based on the difference.

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