Method and electronic device for obtaining initial value of combined navigation calibration based on high-precision map

Abstract

The present invention provides a method for obtaining initial values ​​of combined navigation calibration based on a high-precision map and an electronic device. The method rigidly mounts the combined navigation to be calibrated on a moving carrier, sets the lever arm value and attitude angle calibration value of the combined navigation to the center of the rear wheel axle to zero, and configures the output point of the combined navigation as the combined navigation center; the combined navigation travels a certain distance along the center line of a fixed lane along the moving carrier, and the combined navigation positioning result during the storage process is recorded as a first point set; the lane center line result of the corresponding lane is extracted from the high-precision map and recorded as a second point set, and the corresponding part is excerpted; the filtered first point set is aligned with the excerpted part of the second point set using a point cloud matching method to obtain an alignment rotation matrix; and the alignment rotation matrix is ​​used to obtain the calibration values ​​of the lever arm value and the attitude angle.

Description

Technical Field

[0001] The present invention belongs to the field of high-precision positioning, and specifically relates to a method for obtaining initial values ​​of combined navigation calibration based on high-precision maps and electronic equipment. Background Art

[0002] At present, after the integrated navigation is installed, in addition to calibrating the integrated navigation to the antenna arm, it is also necessary to calibrate the integrated navigation to the rear axle center arm to obtain the accurate vehicle position.

[0003] In reality, manual measurements of the xyz-axis lever arms and attitude angles are required as initial values ​​to be input into the integrated navigation calibration program. Without a complete vehicle digital model, manually measuring the lever arms to the rear axle using integrated navigation requires visual inspection to ensure parallelism. Manual measurement can introduce significant measurement errors, resulting in suboptimal calibration results. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method and electronic equipment for obtaining initial values ​​of combined navigation calibration based on high-precision maps to improve calibration accuracy.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: a method for obtaining initial values ​​of combined navigation calibration based on high-precision maps,

[0006] The integrated navigation system to be calibrated is rigidly mounted on a moving carrier, the arm value and attitude angle calibration value of the integrated navigation system to the rear wheel axle center are set to zero, and the output point of the integrated navigation system configuration is the integrated navigation system center;

[0007] The combined navigation system drives the moving vehicle along the center line of a fixed lane for a certain distance, and the combined navigation positioning results in the storage process are recorded as a first point set; coordinate conversion and filtering are performed on the positioning points in the first point set;

[0008] Extracting the lane centerline of the corresponding lane from the high-precision map as a second point set; extracting the corresponding portion from the positioning points in the second point set based on the filtered first point set;

[0009] Using the point cloud matching method, the filtered first point set is registered with the selected part of the second point set to obtain the registration rotation matrix;

[0010] The corresponding translation and rotation are obtained by aligning the rotation matrix, the translation is decomposed to obtain the calibration value of the lever arm value, and the rotation is converted to obtain the attitude angle calibration value.

[0011] According to the above solution, the moving carrier is also equipped with a lane centering system, so that the moving carrier travels along the center line of a fixed lane.

[0012] According to the above solution, before the combined navigation system travels a certain distance along the center line of a fixed lane with the moving carrier, it is powered on first and waits for the combined navigation RTK positioning to converge, the state is a fixed solution, and it remains stationary for a period of time.

[0013] According to the above solution, the fixed lane includes at least one curve with a large angle, and the angle of the curve is such that the heading angle and roll angle of the combined navigation have certain changes when passing through the curve.

[0014] According to the above solution, the moving carrier remains stationary for a period of time before and after traveling a certain distance along the center line of a fixed lane.

[0015] According to the above solution, the attributes of the first point set include timestamp, longitude, latitude, high level, roll angle, pitch angle and heading angle.

[0016] According to the above solution, the attributes of the second point set include longitude, latitude, elevation, transverse slope, longitudinal slope and azimuth.

[0017] According to the above solution, the coordinate transformation and filtering of the positioning points in the first point set are specifically as follows:

[0018] Convert latitude and longitude information into projection coordinate information, the projection method is Gaussian projection or UTM projection;

[0019] Extract the starting stationary point and the ending stationary point from the first point set, and filter out points whose timestamps are before the starting stationary point and after the ending stationary point.

[0020] According to the above solution, the corresponding part selected from the positioning points in the second point set is specifically:

[0021] By using a nearest neighbor search algorithm, the points closest to the starting stationary point and the ending stationary point are found in the second point set, recorded as the starting section point and the ending section point, and the points before the starting section point and after the ending section point are filtered out.

[0022] As a second aspect, the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method when executing the computer program.

[0023] The beneficial effects of the present invention are as follows: the present invention carries the combined navigation on a moving carrier, travels a certain distance on a section of road, and uses the point cloud matching method to align the positioning information collected by the combined navigation with the information of the high-precision map of the same section of road, and obtains the calibration values ​​of the lever arm value and the attitude angle based on the alignment rotation matrix; the present invention avoids the errors caused by manual measurement and improves the calibration accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a flow chart of a method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to specific examples and accompanying drawings.

[0026] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0027] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0028] Integrated navigation calibration primarily involves measuring the initial values ​​of the rear axle lever and attitude angles. Six key components of integrated navigation calibration are required: the x-axis lever, y-axis lever, z-axis lever, roll angle, pitch angle, and yaw angle in the vehicle coordinate system.

[0029] like Figure 1 As shown, the present invention provides a method for obtaining initial values ​​of integrated navigation calibration based on high-precision maps, which specifically includes the following steps:

[0030] S1. Rigidly install the integrated navigation system to be calibrated on a moving carrier, set the lever arm value and attitude angle calibration value of the integrated navigation system to the rear wheel axle center to zero, and configure the output point of the integrated navigation system as the integrated navigation center.

[0031] In some embodiments of the present invention, the moving carrier is a vehicle, but other moving carriers may also be used, such as bicycles, motorcycles, electric vehicles, or people. The integrated navigation is rigidly mounted on the moving carrier to ensure that the path of the integrated navigation is consistent with that of the moving carrier without jitter.

[0032] When no calibration is performed, the lever arm value and attitude angle calibration value of the combined navigation to the rear axle center are first set to zero, and then the initial calibration value is obtained and then assigned.

[0033] S2. The combined navigation system drives the moving vehicle along the center line of a fixed lane for a certain distance, and stores the combined navigation positioning results in the process as a first point set; coordinate conversion and filtering are performed on the positioning points in the first point set.

[0034] In certain embodiments of the present invention, the moving carrier is a vehicle equipped with a high-precision map and a lane centering system, so that the moving carrier can travel a certain distance along the center line of a fixed lane more smoothly.

[0035] The calibration of the combined navigation requires the completion of the calibration of six major parts, namely the x-axis arm, y-axis arm, z-axis arm, roll angle roll, pitch angle pitch and heading angle yaw in the vehicle coordinate system. If there are only straight roads, the heading angle yaw and roll angle roll basically do not change much, and the calibration of the heading angle yaw and roll angle roll cannot be completed. Therefore, in certain embodiments of the present invention, the fixed lane should include at least one large-angle curve, and the angle of the curve is such that when passing through the curve, the heading angle and roll angle of the combined navigation have a certain change. In certain embodiments of the present invention, the radius of curvature of the large-angle curve is less than 100 meters. In this way, it is possible to ensure that the heading angle yaw and the roll angle roll have relatively obvious changes by driving on the curve.

[0036] Furthermore, before departure, the vehicle is powered on and waits for the integrated navigation RTK positioning to converge, the state is a fixed solution, and it remains stationary for a period of time. At this time, the integrated navigation locates the vehicle's starting stationary point V1_start.

[0037] The vehicle lane centering system is started, and the vehicle travels a certain distance along the fixed lane and stops for a period of time at the end. At this time, the integrated navigation locates the vehicle's end stationary point V1_end.

[0038] The combined navigation positioning results within this period are stored as the first point set V1. The attributes of the first point set include timestamp, longitude, latitude, high altitude, roll angle, pitch angle and heading angle, etc. The starting stationary point V1_start and the ending stationary point V1_end are both in the first point set V1.

[0039] The latitude and longitude information of the positioning points in the first point set V1 are converted into projection coordinate information, and the projection method is not limited, such as Gaussian projection or UTM projection.

[0040] The starting still point V1_start and the ending still point V1_end are extracted from the first point set V1, and then points with time stamps before the starting still point V1_start and after the ending still point V1_end are filtered out.

[0041] In this way, the data of the first point set V1 is processed and filtered.

[0042] It should be noted that the above only provides one method for processing and filtering the data of the first point set V1, namely, using a stationary method to obtain the starting and ending points. Of course, other methods can also be used to process and filter the data of the first point set V1, as long as the positioning data between the starting stationary point V1_start and the ending stationary point V1_end can be obtained for the integrated navigation.

[0043] S3. Extract the lane centerline of the corresponding lane from the high-precision map and record it as a second point set. The lane centerline includes information such as longitude, latitude, elevation, transverse slope, longitudinal slope, and azimuth.

[0044] Based on the filtered first point set, a corresponding portion is selected from the positioning points in the second point set. In certain embodiments of the present invention, a nearest neighbor search algorithm is used to find the point closest to the starting stationary point V1_start in the second point set V2, denoted as the starting selected point V2_start, and the point closest to the ending stationary point V1_end is found, denoted as the ending selected point V2_end. The nearest neighbor search algorithm can be KNN or various variants thereof.

[0045] Then, the positioning points before the starting section selection point V2_start and after the ending section selection point V2_end in the second point set V2 are filtered out.

[0046] S4. Use the point cloud matching method to align the filtered first point set with the selected part of the second point set to obtain the registration rotation matrix M.

[0047] The point cloud matching method may be the commonly used ICP, NDT and their related variants.

[0048] S5. Obtain the corresponding translation T and rotation R through the registration rotation matrix conversion, decompose the translation T to obtain the calibration values ​​of the lever arm values ​​x, y, and z in the three axis directions, and convert the rotation R to obtain the attitude angle calibration values, namely the roll angle roll, pitch angle pitch, and heading angle yaw, and finally obtain the calibration initial value of the combined navigation.

[0049] As a second aspect, the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method when executing the computer program.

[0050] By adopting the method of the present invention, it is only necessary to drive a certain distance in a lane to provide a relatively accurate initial value for the combined navigation calibration based on the high-precision map, thereby avoiding the errors caused by manual measurement and improving the calibration quality of the combined navigation.

[0051] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0052] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all such improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps, characterized by: The integrated navigation system to be calibrated is rigidly mounted on a moving carrier, the arm value and attitude angle calibration value of the integrated navigation system to the rear wheel axle center are set to zero, and the output point of the integrated navigation system configuration is the integrated navigation system center; The combined navigation follows the moving carrier along the center line of a fixed lane for a distance, and the combined navigation positioning results in the storage process are recorded as the first point set; Perform coordinate transformation and filtering on the positioning points in the first point set; Extracting the lane centerline of the corresponding lane from the high-precision map as a second point set; extracting the corresponding portion from the positioning points in the second point set based on the filtered first point set; Using the point cloud matching method, the filtered first point set is registered with the selected part of the second point set to obtain the registration rotation matrix; The corresponding translation and rotation are obtained by aligning the rotation matrix, the translation is decomposed to obtain the calibration value of the lever arm value, and the rotation is converted to obtain the attitude angle calibration value.

2. The method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps according to claim 1, characterized in that: The motion carrier is also equipped with a lane centering system, so that the motion carrier travels along the center line of a fixed lane.

3. The method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps according to claim 1, characterized in that: Before the combined navigation system and the moving carrier travel a certain distance along the center line of a fixed lane, the system is powered on and waits for the combined navigation RTK positioning to converge, become a fixed solution, and remain stationary for a period of time.

4. The method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps according to claim 1, characterized in that: The fixed lane includes at least one curve with a large angle; the angle of the curve is such that the heading angle and roll angle of the combined navigation have a certain change when passing through the curve.

5. The method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps according to claim 1, characterized in that: The moving carrier remains stationary for a period of time before and after traveling a certain distance along the center line of a fixed lane.

6. The method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps according to claim 1, characterized in that: The attributes of the first point set include timestamp, longitude, latitude, high altitude, roll angle, pitch angle and heading angle.

7. The method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps according to claim 1, characterized in that: The attributes of the second point set include longitude, latitude, elevation, transverse slope, longitudinal slope and azimuth.

8. The method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps according to claim 5, characterized in that: The coordinate transformation and filtering of the positioning points in the first point set are specifically as follows: Convert latitude and longitude information into projection coordinate information, the projection method is Gaussian projection or UTM projection; Extract the starting stationary point and the ending stationary point from the first point set, and filter out points whose timestamps are before the starting stationary point and after the ending stationary point.

9. The method for obtaining initial values ​​for integrated navigation calibration based on high-precision maps according to claim 8, characterized in that: The corresponding part selected from the positioning points in the second point set is specifically: By using a nearest neighbor search algorithm, the points closest to the starting stationary point and the ending stationary point are found in the second point set, recorded as the starting section point and the ending section point, and the points before the starting section point and after the ending section point are filtered out.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method according to any one of claims 1 to 9 when executing the computer program.

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