Laser radar calibration method, device and system, electronic equipment and storage medium

Abstract

The invention relates to a laser radar calibration method, device and system, electronic equipment and a storage medium, and is applied to the technical field of laser radars, and the method comprises the steps: collecting first point cloud data in a target scene under a world coordinate system through the calibration equipment; position coordinates of the first point cloud data are determined according to GPS coordinates collected by an RTK module in the calibration equipment, final calibration parameters of a calibrated laser radar in the calibration equipment and original point cloud data collected by the calibrated laser radar; acquiring second point cloud data in the target scene under the radar coordinate system by using a to-be-calibrated target laser radar; performing time synchronization on the target laser radar and the calibration equipment; and matching the first point cloud data and the second point cloud data by using an iterative nearest point algorithm, and determining calibration parameters of the target laser radar. The efficiency and accuracy of laser radar calibration can be improved.

Description

Technical Field

[0001] The present application relates to the field of laser radar technology, and in particular to a laser radar calibration method, device, system, electronic device and storage medium. Background Art

[0002] At present, sensor technology is developing rapidly, and various types of sensors are widely used in fields such as robots and autonomous driving. By integrating multiple positioning sensors, more stable and reliable positioning information can be obtained, improving the robustness of the system. In the high-precision positioning and environmental perception of robots, LiDAR is a commonly used technology. LiDAR emits a laser beam and receives the signal reflected from the target. After comparing and processing it, it can obtain key parameters such as the target's position information, height, and speed.

[0003] In the related art, the laser radar can be calibrated based on a step-by-step iterative algorithm that matches the feature point cloud ICP (Iterative Closest Point). However, the calibration process usually requires multiple steps (data collection, conversion, calculation, verification), has a low degree of automation, requires manual measurement and adjustment, is inefficient and prone to errors. When extracting feature points, the corresponding RTK (Real-time kinematic) data may not be accurate, resulting in low calibration accuracy. Summary of the invention

[0004] In order to solve the above technical problems, the present application provides a laser radar calibration method, device, system, electronic device and storage medium.

[0005] According to a first aspect of the present application, a laser radar calibration method is provided, comprising:

[0006] The calibration device is used to collect first point cloud data in the target scene in the world coordinate system; the position coordinates of the first point cloud data are determined according to the GPS (Global Positioning System) coordinates collected by the RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar;

[0007] The target laser radar to be calibrated is used to collect second point cloud data in the target scene in the radar coordinate system; the target laser radar and the calibration device are time synchronized;

[0008] The first point cloud data and the second point cloud data are matched by using an iterative closest point algorithm to determine the calibration parameters of the target laser radar.

[0009] Optionally, after determining the calibration parameters of the target laser radar to be calibrated, the method further includes:

[0010] Using the calibration device to collect third point cloud data in the test scene in the world coordinate system;

[0011] Using the target laser radar to collect fourth point cloud data in the test scene in the radar coordinate system;

[0012] Determining fifth point cloud data in a world coordinate system according to the fourth point cloud data and the calibration parameters;

[0013] Calculating a point cloud overlap between the third point cloud data and the fifth point cloud data, and determining a calibration error according to the point cloud overlap;

[0014] If the calibration error is less than or equal to a preset calibration error, configuring the target laser radar according to the calibration parameters;

[0015] If the calibration error is greater than the preset calibration error, adjust the posture or acquisition parameters of the target lidar, and return to the step of using the calibration device to collect the first point cloud data in the target scene in the world coordinate system.

[0016] Optionally, before collecting the first point cloud data in the target scene in the world coordinate system using the calibration device, the method further includes:

[0017] Use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system;

[0018] Using an uncalibrated laser radar in the calibration device to scan the position of the marker point to obtain point cloud data of the marker point in the radar coordinate system;

[0019] Collecting GPS coordinates using the RTK module in the calibration device, and determining the position coordinates of the uncalibrated laser radar in the world coordinate system according to the GPS coordinates and the predetermined initial calibration parameters;

[0020] According to the position coordinates of the uncalibrated laser radar in the world coordinate system, the point cloud data and the position coordinates of the marker points in the world coordinate system, the marker points are matched using an iterative closest point algorithm to optimize the initial calibration parameters and obtain the final calibration parameters.

[0021] Optionally, before determining the position coordinates of the uncalibrated laser radar in the world coordinate system according to the GPS coordinates and the predetermined initial calibration parameters, the method further includes:

[0022] Using a three-coordinate measuring machine to measure the position and posture of the RTK module and the uncalibrated laser radar in the calibration device;

[0023] According to the position and posture of the RTK module and the uncalibrated laser radar, initial calibration parameters of the uncalibrated laser radar are determined.

[0024] Optionally, before collecting the first point cloud data in the target scene in the world coordinate system using the calibration device, the method further includes:

[0025] Use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system;

[0026] Using the candidate RTK module to collect the GPS coordinates of the landmark points;

[0027] Calculate the error of the candidate RTK module according to the position coordinates measured by the total station and the GPS coordinates collected by the candidate RTK module;

[0028] If the error of the candidate RTK module is less than or equal to a preset position error, the candidate RTK module is set in the calibration device.

[0029] Optionally, the measuring the position coordinates of the preset marker points in the world coordinate system by using a total station includes:

[0030] Use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system multiple times;

[0031] For each marker point, calculate the mean and standard deviation of the position coordinates of the marker point;

[0032] The standard deviation of the marker point is smaller than the mean value corresponding to the preset standard deviation, and is used as the position coordinate of the marker point.

[0033] According to a second aspect of the present application, a laser radar calibration device is provided, comprising:

[0034] A first point cloud data acquisition module is used to collect first point cloud data in the target scene in the world coordinate system using a calibration device; the position coordinates of the first point cloud data are determined according to the GPS coordinates collected by the RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar;

[0035] A second point cloud data acquisition module is used to acquire second point cloud data in the target scene in the radar coordinate system using the target laser radar to be calibrated; the target laser radar and the calibration device are time synchronized;

[0036] The calibration parameter determination module is used to match the first point cloud data and the second point cloud data using an iterative closest point algorithm to determine the calibration parameters of the target laser radar.

[0037] Optionally, the laser radar calibration device further includes:

[0038] A calibration error verification module is used to use the calibration device to collect third point cloud data in the test scene in the world coordinate system; use the target laser radar to collect fourth point cloud data in the test scene in the radar coordinate system; determine the fifth point cloud data in the world coordinate system according to the fourth point cloud data and the calibration parameters; calculate the point cloud overlap between the third point cloud data and the fifth point cloud data, and determine the calibration error according to the point cloud overlap; if the calibration error is less than or equal to the preset calibration error, configure the target laser radar according to the calibration parameters; if the calibration error is greater than the preset calibration error, adjust the posture or acquisition parameters of the target laser radar, and return to the first point cloud data acquisition module.

[0039] Optionally, the laser radar calibration device further includes:

[0040] The final calibration parameter determination module is used to use a total station to measure the position coordinates of a preset marker point in a world coordinate system; use an uncalibrated laser radar in the calibration device to scan the position of the marker point to obtain point cloud data of the marker point in the radar coordinate system; use the RTK module in the calibration device to collect GPS coordinates, and determine the position coordinates of the uncalibrated laser radar in the world coordinate system based on the GPS coordinates and pre-determined initial calibration parameters; use an iterative closest point algorithm to match the marker point based on the position coordinates of the uncalibrated laser radar in the world coordinate system, the point cloud data and the position coordinates of the marker point in the world coordinate system to optimize the initial calibration parameters and obtain the final calibration parameters.

[0041] Optionally, the laser radar calibration device further includes:

[0042] The initial calibration parameter determination module is used to measure the posture of the RTK module and the uncalibrated laser radar in the calibration device using a three-coordinate measuring instrument; and determine the initial calibration parameters of the uncalibrated laser radar according to the posture of the RTK module and the uncalibrated laser radar.

[0043] Optionally, the laser radar calibration device further includes:

[0044] The RTK module selection module is used to use a total station to measure the position coordinates of a pre-set marker point in a world coordinate system; use a candidate RTK module to collect the GPS coordinates of the marker point; calculate the error of the candidate RTK module based on the position coordinates measured by the total station and the GPS coordinates collected by the candidate RTK module; if the error of the candidate RTK module is less than or equal to the preset position error, set the candidate RTK module in the calibration device.

[0045] Optionally, the final calibration parameter determination module or the RTK module selection module is specifically used to measure the position coordinates of the preset marker points in the world coordinate system using a total station through the following steps:

[0046] Use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system multiple times;

[0047] For each marker point, calculate the mean and standard deviation of the position coordinates of the marker point;

[0048] The standard deviation of the marker point is smaller than the mean value corresponding to the preset standard deviation, and is used as the position coordinate of the marker point.

[0049] According to a third aspect of the present application, a laser radar calibration system is provided, the system comprising: a calibration device and a target laser radar to be calibrated;

[0050] The calibration device is used to collect first point cloud data in the target scene in the world coordinate system; the position coordinates of the first point cloud data are determined according to the GPS coordinates collected by the RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar;

[0051] The target laser radar to be calibrated is used to collect second point cloud data in the target scene in the radar coordinate system; the target laser radar and the calibration device are time synchronized;

[0052] The calibration device is also used to match the first point cloud data and the second point cloud data using an iterative closest point algorithm to determine the calibration parameters of the target laser radar.

[0053] Optionally, the calibration device is also used to use the calibration device to collect third point cloud data in the test scene in the world coordinate system; use the target laser radar to collect fourth point cloud data in the test scene in the radar coordinate system; determine the fifth point cloud data in the world coordinate system based on the fourth point cloud data and the calibration parameters; calculate the point cloud overlap between the third point cloud data and the fifth point cloud data, and determine the calibration error based on the point cloud overlap; if the calibration error is less than or equal to a preset calibration error, configure the target laser radar according to the calibration parameters; if the calibration error is greater than the preset calibration error, adjust the posture or acquisition parameters of the target laser radar, and return to the first point cloud data acquisition module.

[0054] Optionally, the system further comprises a total station;

[0055] Total station, used to measure the position coordinates of pre-set marker points in the world coordinate system;

[0056] The calibration device is also used to use the uncalibrated laser radar in the calibration device to scan the position of the marker point to obtain the point cloud data of the marker point in the radar coordinate system; use the RTK module in the calibration device to collect GPS coordinates, and determine the position coordinates of the uncalibrated laser radar in the world coordinate system based on the GPS coordinates and pre-determined initial calibration parameters; according to the position coordinates of the uncalibrated laser radar in the world coordinate system, the point cloud data and the position coordinates of the marker point in the world coordinate system, use an iterative closest point algorithm to match the marker point to optimize the initial calibration parameters and obtain the final calibration parameters.

[0057] Optionally, the system further comprises: a three-coordinate measuring machine;

[0058] A three-coordinate measuring instrument, used to measure the position and posture of the RTK module and the uncalibrated laser radar in the calibration equipment;

[0059] The calibration device is also used to determine the initial calibration parameters of the uncalibrated laser radar according to the position and posture of the RTK module and the uncalibrated laser radar.

[0060] Optionally, the system further comprises: a total station;

[0061] Total station, used to measure the position coordinates of pre-set marker points in the world coordinate system;

[0062] The calibration device is also used to collect the GPS coordinates of the marker point using the candidate RTK module; calculate the error of the candidate RTK module based on the position coordinates measured by the total station and the GPS coordinates collected by the candidate RTK module; if the error of the candidate RTK module is less than or equal to the preset position error, the candidate RTK module is set in the calibration device.

[0063] Optionally, a total station is specifically used to measure the position coordinates of pre-set marker points in a world coordinate system multiple times;

[0064] The calibration device is also used to calculate the mean and standard deviation of the position coordinates of each marker point; and use the mean corresponding to the standard deviation of the marker point being smaller than the preset standard deviation as the position coordinates of the marker point.

[0065] According to a fourth aspect of the present application, an electronic device is provided, comprising: a processor, wherein the processor is used to execute a computer program stored in a memory, wherein the computer program implements the method described in the first aspect when executed by the processor.

[0066] According to a fifth aspect of the present application, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the method described in the first aspect is implemented.

[0067] According to a sixth aspect of the present application, a computer program product is provided. When the computer program product is run on a computer, the computer is caused to execute the method described in the first aspect.

[0068] Compared with the prior art, the technical solution provided by the embodiments of the present application has the following advantages:

[0069] The calibration equipment based on the RTK module and the calibrated LiDAR realizes efficient calibration and registration by integrating high-precision positioning and environmental perception technology. Specifically, the calibration equipment uses the RTK module and LiDAR to collect environmental data, and accurately outputs point cloud data in the world coordinate system through a preset algorithm, providing high-reliability basic data for the LiDAR to be calibrated. Using the iterative closest point algorithm, the point cloud data in the radar coordinate system collected by the LiDAR to be calibrated and the point cloud data in the world coordinate system are matched to determine the calibration parameters of the LiDAR to be calibrated. The calibration equipment can automatically complete the generation, synchronization and registration of point cloud data, reducing manual intervention. This standardized process significantly improves the calibration efficiency. In addition, the point cloud data in the world coordinate system output by the calibration equipment reduces manual measurement and feature point extraction errors, and improves the accuracy of calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0071] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0072] Figure 1 A flow chart of a laser radar calibration method in an embodiment of the present application;

[0073] Figure 2 This is a flow chart of a method for determining final calibration parameters in an embodiment of the present application;

[0074] Figure 3 This is another flow chart of the laser radar calibration method in the embodiment of the present application;

[0075] Figure 4 A schematic diagram of the structure of a laser radar calibration device in an embodiment of the present application;

[0076] Figure 5 A schematic diagram of the structure of a laser radar calibration system in an embodiment of the present application;

[0077] Figure 6 A schematic diagram of the structure of an electronic device in an embodiment of the present application. DETAILED DESCRIPTION

[0078] In order to more clearly understand the above-mentioned purposes, features and advantages of the present application, the scheme of the present application will be further described below. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0079] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only part of the embodiments of the present application, rather than all of the embodiments.

[0080] See also Figure 1 , Figure 1 This is a flow chart of a laser radar calibration method in an embodiment of the present application, which may include the following steps:

[0081] Step S102, using the calibration device to collect the first point cloud data in the target scene in the world coordinate system; the position coordinates of the first point cloud data are determined according to the GPS coordinates collected by the RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar.

[0082] The calibration equipment is used to calibrate the LiDAR. The calibration equipment includes the RTK module and the calibrated LiDAR. The calibration equipment can combine the timestamp of the RTK module to achieve nanosecond time synchronization between the calibration equipment and the LiDAR to be calibrated, support phase synchronization, and ensure the relative time and space consistency of the point clouds collected by the two radars. The RTK module can provide centimeter-level high-precision position information, output the position and attitude data of the device in the world coordinate system in real time, support multi-band reception, have the ability to resist multipath interference, and ensure stability. The calibrated LiDAR is a high-precision industrial-grade LiDAR that provides multi-beam point cloud acquisition capabilities, has a high scanning frequency and a large field of view, and is suitable for data acquisition in complex scenes.

[0083] The RTK module can collect GPS coordinates, that is, the location coordinates of the RTK module. The calibrated lidar can collect original point cloud data in the target scene. According to the GPS coordinates, the original point cloud data and the final calibration parameters of the calibrated lidar, the first point cloud data in the world coordinate system can be obtained.

[0084] Optionally, a total station can be used to measure the position coordinates of a pre-set marker point in the world coordinate system. The GPS coordinates of the marker point are collected using the candidate RTK module. The error of the candidate RTK module is calculated based on the position coordinates measured by the total station and the GPS coordinates collected by the candidate RTK module. If the error of the candidate RTK module is less than or equal to the preset position error (e.g., 2 mm), the candidate RTK module is set in the calibration device, so that the accuracy of the RTK module in the calibration device can be guaranteed.

[0085] See also Figure 2 , Figure 2 The method for determining the final calibration parameters in the embodiment of the present application may include the following steps:

[0086] Step S202: Use a total station to measure the position coordinates of the pre-set marker points in the world coordinate system.

[0087] The calibration environment can be an indoor environment to avoid interference from light reflection and air flow disturbance. The calibration space size is at least 10m×10m×10m. Auxiliary equipment can include a high-precision total station, which is used to establish a reference world coordinate system for the calibration site. Using a total station to establish a spatial reference coordinate system, more than 20 high-precision markers can be arranged. The markers are special reflective spheres or plate-shaped markers with known size and reflection characteristics. The coordinates of the markers are known, and the markers are evenly distributed, covering the boundaries and central areas of the calibration space. The position error of the markers is less than 0.5mm.

[0088] Use the total station to measure the positions of all the landmarks in the laboratory one by one, and establish the world coordinate system W in the laboratory. The coordinates of each landmark are expressed as:

[0089] N represents the total number of landmarks.

[0090] Optionally, the total station can be used to measure the position coordinates of the pre-set marker points in the world coordinate system for multiple times. For each marker point, the mean and standard deviation of the position coordinates of the marker point are calculated. The mean corresponding to the standard deviation of the marker point being less than the preset standard deviation (for example, 0.5 mm) is used as the position coordinate of the marker point. In this way, the stability and consistency of the position coordinates of each marker point in the world coordinate system can be ensured, thereby improving the accuracy of the laser radar calibration in the calibration device.

[0091] Step S204, using the uncalibrated laser radar in the calibration device to scan the position of the marker point, to obtain the point cloud data of the marker point in the radar coordinate system.

[0092] Step S206, using the RTK module in the calibration device to collect GPS coordinates, and determining the position coordinates of the uncalibrated laser radar in the world coordinate system based on the GPS coordinates and the predetermined initial calibration parameters.

[0093] The initial calibration parameters include: initial rotation matrix R init and the initial translation matrix t init The initial calibration parameters can represent the positional relationship between the RTK module and the uncalibrated laser radar. Therefore, according to the GPS coordinates and the initial calibration parameters, the position coordinates of the laser radar in the world coordinate system can be determined. Optionally, the initial calibration parameters can be determined by the following method:

[0094] The three-coordinate measuring machine is used to measure the pose of the RTK module and the uncalibrated laser radar in the calibration equipment. According to the pose of the RTK module and the uncalibrated laser radar, the initial calibration parameters of the uncalibrated laser radar are determined.

[0095] Step S208, according to the position coordinates of the uncalibrated laser radar in the world coordinate system, the point cloud data and the position coordinates of the marker points in the world coordinate system, the iterative closest point algorithm is used to match the marker points to optimize the initial calibration parameters and obtain the final calibration parameters.

[0096] Assume P w，lidar Represents the position coordinates of the laser radar in the world coordinate system, P lidar，i Indicates the position coordinates of the marker point in the radar coordinate system, P w，i Represents the position coordinates of the marker point in the world coordinate system, optimized according to the iterative closest point algorithm:

[0097]

[0098] Minimize the sum of squared Euclidean distances between two point clouds. Solve the optimal rotation matrix R and translation vector t through SVD (singular value decomposition). You can also collect random points in the calibration space to verify the accuracy of the rotation matrix R and translation vector t. After verification, the rotation matrix R and translation vector t are used to accurately calibrate the laser radar to be calibrated.

[0099] During the use phase, the calibration equipment collects GPS coordinates P in real time through the RTK module. RTK , the calibrated laser radar collects the original point cloud data P in real time lidar ={p1, p2, ..., p n}. According to the formula: P world，j =P RTK +R·P lidar，j +t, you can get the first point cloud data in the world coordinate system, P lidar，jrepresents the position coordinates of the jth point cloud in the radar coordinate system, P world，j Represents the position coordinates of the jth point cloud in the world coordinate system.

[0100] Step S104, using the target laser radar to be calibrated to collect second point cloud data in the target scene in the radar coordinate system; the target laser radar and the calibration device are time synchronized.

[0101] The target laser radar to be calibrated and the calibration device collect point cloud data in the same scene (ie, the target scene) to obtain second point cloud data.

[0102] Step S106, using an iterative closest point algorithm, matching the first point cloud data and the second point cloud data to determine the calibration parameters of the target laser radar.

[0103] Assume that table p world，j represents the jth first point cloud data, p raw，j Represents the j-th second point cloud data, which can be expressed according to the following formula:

[0104]

[0105] Determine the calibration parameters R and t of the target lidar.

[0106] The laser radar calibration method of the embodiment of the present application is based on the calibration equipment of the RTK module and the calibrated laser radar, and realizes efficient calibration and registration by integrating high-precision positioning and environmental perception technology. Specifically, the calibration equipment uses the RTK module and the laser radar to collect environmental data, and accurately outputs the point cloud data in the world coordinate system through a preset algorithm, providing high-reliability basic data for the laser radar to be calibrated. Using the iterative closest point algorithm, the point cloud data in the radar coordinate system collected by the laser radar to be calibrated and the point cloud data in the world coordinate system are matched to determine the calibration parameters of the laser radar to be calibrated. The calibration equipment can automatically complete the generation, synchronization and registration of point cloud data, reduce manual intervention, and the standardized process significantly improves the calibration efficiency. In addition, the point cloud data in the world coordinate system output by the calibration equipment reduces manual measurement and feature point extraction errors, and improves the accuracy of calibration. Even in a complex environment with moving objects, time synchronization and phase synchronization ensure that dynamic targets do not interfere with the calibration process, avoiding the limitation of traditional calibration relying on static scenes. The calibration device supports joint calibration with multiple sensors (such as inertial measurement units, cameras, etc.) to meet more complex calibration requirements.

[0107] See also Figure 3 , Figure 3 This is another flow chart of the laser radar calibration method in the embodiment of the present application. Figure 1 The following steps may also be included based on the embodiment:

[0108] Step S302: collect third point cloud data in the test scene in the world coordinate system using a calibration device.

[0109] Step S304, using the target laser radar to collect fourth point cloud data in the test scene in the radar coordinate system.

[0110] Step S306: Determine fifth point cloud data in the world coordinate system according to the fourth point cloud data and the calibration parameters.

[0111] Step S308, calculating the point cloud overlap between the third point cloud data and the fifth point cloud data, and determining the calibration error according to the point cloud overlap.

[0112] Step S310, determining whether the calibration error is greater than a preset calibration error.

[0113] If the calibration error is less than or equal to the preset calibration error, it means that the calibration accuracy of the target laser radar is high, and step S312 is executed; if the calibration error is greater than the preset calibration error, it means that the calibration accuracy of the target laser radar is low, and step S314 is executed.

[0114] Step S312, configuring the target laser radar according to the calibration parameters.

[0115] The calibration parameters are solidified inside the target LiDAR device so that the target LiDAR can directly output point cloud data in the world coordinate system when collecting point cloud data.

[0116] Step S314, adjust the position or acquisition parameters of the target laser radar, and return to step S102.

[0117] The height and angle of the target LiDAR affect the density of the target interval point cloud. The position and posture of the target LiDAR are adjusted, including but not limited to the height and angle of the target LiDAR. The acquisition parameters are mainly used to optimize the software configuration during the acquisition process and improve the quality of the point cloud. The adjustment of the acquisition parameters includes but is not limited to modifying the quality of the radar point cloud data, reducing noise and distortion, ensuring the time synchronization consistency of the target LiDAR and the calibration equipment to reduce the matching deviation caused by time deviation, etc.

[0118] After adjusting the position or acquisition parameters of the target laser radar, return to step S102 to recalibrate the target laser radar until the calibration accuracy of the target laser radar meets the requirements. In this way, it can be ensured that the final calibration result has a sufficiently high accuracy.

[0119] Corresponding to the above method embodiment, the present application embodiment also provides a laser radar calibration device, see Figure 4 , the laser radar calibration device 400 includes:

[0120] The first point cloud data acquisition module 402 is used to collect the first point cloud data in the target scene in the world coordinate system using the calibration device; the position coordinates of the first point cloud data are determined according to the GPS coordinates collected by the RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar;

[0121] The second point cloud data acquisition module 404 is used to collect second point cloud data in the target scene in the radar coordinate system using the target laser radar to be calibrated; the target laser radar and the calibration device are time synchronized;

[0122] The calibration parameter determination module 406 is used to match the first point cloud data and the second point cloud data using an iterative closest point algorithm to determine the calibration parameters of the target laser radar.

[0123] Optionally, the laser radar calibration device 400 further includes:

[0124] The calibration error verification module is used to collect the third point cloud data in the test scene in the world coordinate system using the calibration equipment; collect the fourth point cloud data in the test scene in the radar coordinate system using the target laser radar; determine the fifth point cloud data in the world coordinate system based on the fourth point cloud data and the calibration parameters; calculate the point cloud overlap between the third point cloud data and the fifth point cloud data, and determine the calibration error based on the point cloud overlap; if the calibration error is less than or equal to the preset calibration error, configure the target laser radar according to the calibration parameters; if the calibration error is greater than the preset calibration error, adjust the position or acquisition parameters of the target laser radar, and return to the first point cloud data acquisition module.

[0125] Optionally, the laser radar calibration device 400 further includes:

[0126] The final calibration parameter determination module is used to use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system; use the uncalibrated laser radar in the calibration equipment to scan the position of the marker points to obtain the point cloud data of the marker points in the radar coordinate system; use the RTK module in the calibration equipment to collect GPS coordinates, and determine the position coordinates of the uncalibrated laser radar in the world coordinate system based on the GPS coordinates and the pre-determined initial calibration parameters; according to the position coordinates of the uncalibrated laser radar in the world coordinate system, the point cloud data and the position coordinates of the marker points in the world coordinate system, use the iterative closest point algorithm to match the marker points to optimize the initial calibration parameters and obtain the final calibration parameters.

[0127] Optionally, the laser radar calibration device 400 further includes:

[0128] The initial calibration parameter determination module is used to measure the posture of the RTK module and the uncalibrated laser radar in the calibration equipment by using a three-coordinate measuring instrument; according to the posture of the RTK module and the uncalibrated laser radar, the initial calibration parameters of the uncalibrated laser radar are determined.

[0129] Optionally, the laser radar calibration device 400 further includes:

[0130] The RTK module selection module is used to measure the position coordinates of the preset marker points in the world coordinate system using the total station; collect the GPS coordinates of the marker points using the candidate RTK module; calculate the error of the candidate RTK module based on the position coordinates measured by the total station and the GPS coordinates collected by the candidate RTK module; if the error of the candidate RTK module is less than or equal to the preset position error, set the candidate RTK module in the calibration device.

[0131] Optionally, the final calibration parameter determination module or the RTK module selection module is specifically used to measure the position coordinates of the preset marker points in the world coordinate system using a total station through the following steps:

[0132] Use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system multiple times;

[0133] For each landmark point, calculate the mean and standard deviation of the location coordinates of the landmark point;

[0134] The standard deviation of the marker point is less than the mean corresponding to the preset standard deviation, which is used as the position coordinate of the marker point.

[0135] The specific details of each module or unit in the above device have been described in detail in the corresponding method, so they will not be repeated here.

[0136] It should be noted that, although several modules or units of the equipment for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more modules or units described above can be embodied in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into being embodied by multiple modules or units.

[0137] The present application also provides a laser radar calibration system. Figure 5 , the laser radar calibration system 500 includes: a calibration device 510 and a target laser radar 520 to be calibrated;

[0138] The calibration device 510 is used to collect first point cloud data in the target scene in the world coordinate system; the position coordinates of the first point cloud data are determined according to the GPS coordinates collected by the RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar;

[0139] The target laser radar 520 to be calibrated is used to collect the second point cloud data in the target scene in the radar coordinate system; the target laser radar and the calibration device are time synchronized;

[0140] The calibration device 510 is also used to match the first point cloud data and the second point cloud data using an iterative closest point algorithm to determine the calibration parameters of the target laser radar.

[0141] Optionally, the calibration device 510 is also used to collect third point cloud data in the test scene in the world coordinate system using the calibration device; collect fourth point cloud data in the test scene in the radar coordinate system using the target laser radar; determine the fifth point cloud data in the world coordinate system based on the fourth point cloud data and the calibration parameters; calculate the point cloud overlap between the third point cloud data and the fifth point cloud data, and determine the calibration error based on the point cloud overlap; if the calibration error is less than or equal to a preset calibration error, configure the target laser radar according to the calibration parameters; if the calibration error is greater than the preset calibration error, adjust the position or acquisition parameters of the target laser radar, and return to the first point cloud data acquisition module.

[0142] Optionally, the laser radar calibration system further includes a total station;

[0143] Total station, used to measure the position coordinates of pre-set marker points in the world coordinate system;

[0144] The calibration device is also used to use the uncalibrated laser radar in the calibration device to scan the position of the marker point to obtain the point cloud data of the marker point in the radar coordinate system; use the RTK module in the calibration device to collect GPS coordinates, and determine the position coordinates of the uncalibrated laser radar in the world coordinate system based on the GPS coordinates and pre-determined initial calibration parameters; use the iterative closest point algorithm to match the marker points based on the position coordinates of the uncalibrated laser radar in the world coordinate system, the point cloud data and the position coordinates of the marker point in the world coordinate system to optimize the initial calibration parameters and obtain the final calibration parameters.

[0145] Optionally, the laser radar calibration system further includes: a three-coordinate measuring instrument;

[0146] Coordinate measuring machine, used to measure the position and posture of the RTK module and uncalibrated lidar in the calibration equipment;

[0147] The calibration device 510 is also used to determine the initial calibration parameters of the uncalibrated laser radar according to the position and posture of the RTK module and the uncalibrated laser radar.

[0148] Optionally, the laser radar calibration system further includes: a total station;

[0149] Total station, used to measure the position coordinates of pre-set marker points in the world coordinate system;

[0150] The calibration device 510 is also used to collect the GPS coordinates of the marker points using the candidate RTK module; calculate the error of the candidate RTK module based on the position coordinates measured by the total station and the GPS coordinates collected by the candidate RTK module; if the error of the candidate RTK module is less than or equal to the preset position error, the candidate RTK module is set in the calibration device.

[0151] Optionally, a total station is specifically used to measure the position coordinates of pre-set marker points in a world coordinate system multiple times;

[0152] The calibration device 510 is also used to calculate the mean and standard deviation of the position coordinates of each marker point; and take the mean corresponding to the standard deviation of the marker point being smaller than the preset standard deviation as the position coordinates of the marker point.

[0153] An embodiment of the present application also provides an electronic device, comprising: a processor; and a memory for storing instructions executable by the processor; wherein the processor is configured to execute the above-mentioned laser radar calibration method in this example implementation.

[0154] Reference Figure 6 , Figure 6 This is a schematic diagram of the structure of an electronic device in an embodiment of the present application. The specific embodiment of the present application does not limit the specific implementation of the electronic device.

[0155] like Figure 6 As shown, the electronic device may include: a processor 602 , a communication interface 604 , a memory 606 , and a communication bus 608 .

[0156] The processor 602 , the communication interface 604 , and the memory 606 communicate with each other via a communication bus 608 .

[0157] The communication interface 604 is used to communicate with other electronic devices or servers.

[0158] The processor 602 is used to execute the program 610, and specifically can execute the relevant steps in the above method embodiment.

[0159] Specifically, the program 610 may include program codes, which include computer operation instructions.

[0160] The processor 602 may be a central processing unit, or a specific integrated circuit, or one or more integrated circuits configured to implement the embodiments of the present application. The one or more processors included in the smart device may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0161] The memory 606 is used to store the program 610. The memory 606 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0162] Program 610 can be specifically used to enable processor 602 to execute the steps in the above-mentioned laser radar calibration method embodiment.

[0163] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding process descriptions in the aforementioned method embodiments and will not be repeated here.

[0164] A computer-readable storage medium is also provided in an embodiment of the present application, on which a computer program is stored. When the computer program is executed by a processor, the above-mentioned laser radar calibration method is implemented.

[0165] It should be noted that the computer-readable storage medium shown in the present application may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, device or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wireless, wire, optical cable, radio frequency, etc., or any suitable combination of the above.

[0166] In an embodiment of the present application, a computer program product is also provided. When the computer program product is run on a computer, the computer executes the above-mentioned laser radar calibration method.

[0167] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0168] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments described herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A laser radar calibration method, characterized in that: include: The calibration device is used to collect first point cloud data in the target scene in the world coordinate system; the position coordinates of the first point cloud data are determined according to the global positioning system GPS coordinates collected by the real-time differential positioning RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar; The target laser radar to be calibrated is used to collect second point cloud data in the target scene in the radar coordinate system; the target laser radar and the calibration device are time synchronized; The first point cloud data and the second point cloud data are matched by using an iterative closest point algorithm to determine the calibration parameters of the target laser radar.

2. The method according to claim 1, characterized in that After determining the calibration parameters of the target laser radar to be calibrated, the method further includes: Using the calibration device to collect third point cloud data in the test scene in the world coordinate system; Using the target laser radar to collect fourth point cloud data in the test scene in the radar coordinate system; Determining fifth point cloud data in a world coordinate system according to the fourth point cloud data and the calibration parameters; Calculating a point cloud overlap between the third point cloud data and the fifth point cloud data, and determining a calibration error according to the point cloud overlap; If the calibration error is less than or equal to a preset calibration error, configuring the target laser radar according to the calibration parameters; If the calibration error is greater than the preset calibration error, adjust the posture or acquisition parameters of the target lidar, and return to the step of using the calibration device to collect the first point cloud data in the target scene in the world coordinate system.

3. The method according to claim 1, characterized in that Before collecting the first point cloud data in the target scene in the world coordinate system by using the calibration device, the method further includes: Use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system; Using an uncalibrated laser radar in the calibration device to scan the position of the marker point to obtain point cloud data of the marker point in the radar coordinate system; Collecting GPS coordinates using the RTK module in the calibration device, and determining the position coordinates of the uncalibrated laser radar in the world coordinate system according to the GPS coordinates and the predetermined initial calibration parameters; According to the position coordinates of the uncalibrated laser radar in the world coordinate system, the point cloud data and the position coordinates of the marker points in the world coordinate system, the marker points are matched using an iterative closest point algorithm to optimize the initial calibration parameters and obtain the final calibration parameters.

4. The method according to claim 3, characterized in that Before determining the position coordinates of the uncalibrated laser radar in the world coordinate system according to the GPS coordinates and the predetermined initial calibration parameters, the method further includes: Using a three-coordinate measuring machine to measure the position and posture of the RTK module and the uncalibrated laser radar in the calibration device; According to the position and posture of the RTK module and the uncalibrated laser radar, initial calibration parameters of the uncalibrated laser radar are determined.

5. The method according to claim 1, characterized in that Before collecting the first point cloud data in the target scene in the world coordinate system using the calibration device, the method further includes: Use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system; Using the candidate RTK module to collect the GPS coordinates of the landmark points; Calculate the error of the candidate RTK module according to the position coordinates measured by the total station and the GPS coordinates collected by the candidate RTK module; If the error of the candidate RTK module is less than or equal to a preset position error, the candidate RTK module is set in the calibration device.

6. The method according to claim 3 or 5, characterized in that: The method of measuring the position coordinates of the preset marker points in the world coordinate system by using a total station includes: Use the total station to measure the position coordinates of the pre-set marker points in the world coordinate system multiple times; For each marker point, calculate the mean and standard deviation of the position coordinates of the marker point; The standard deviation of the marker point is smaller than the mean value corresponding to the preset standard deviation, and is used as the position coordinate of the marker point.

7. A laser radar calibration device, characterized in that: The device comprises: A first point cloud data acquisition module is used to collect first point cloud data in the target scene in the world coordinate system using a calibration device; the position coordinates of the first point cloud data are determined according to the global positioning system GPS coordinates collected by the real-time differential positioning RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar; A second point cloud data acquisition module is used to acquire second point cloud data in the target scene in the radar coordinate system using the target laser radar to be calibrated; the target laser radar and the calibration device are time synchronized; The calibration parameter determination module is used to match the first point cloud data and the second point cloud data using an iterative closest point algorithm to determine the calibration parameters of the target laser radar.

8. A laser radar calibration system, characterized in that: The system comprises: a calibration device and a target laser radar to be calibrated; The calibration device is used to collect first point cloud data in the target scene in the world coordinate system; the position coordinates of the first point cloud data are determined according to the global positioning system GPS coordinates collected by the real-time differential positioning RTK module in the calibration device, the final calibration parameters of the calibrated laser radar in the calibration device, and the original point cloud data collected by the calibrated laser radar; The target laser radar to be calibrated is used to collect second point cloud data in the target scene in the radar coordinate system; the target laser radar and the calibration device are time synchronized; The calibration device is also used to match the first point cloud data and the second point cloud data using an iterative closest point algorithm to determine the calibration parameters of the target laser radar.

9. An electronic device, characterized in that: include: A processor, wherein the processor is used to execute a computer program stored in a memory, wherein the computer program, when executed by the processor, implements the method according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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