阅读说明：本技术 激光雷达与组合惯导的位姿标定方法、系统及介质 (Pose calibration method, system and medium for laser radar and combined inertial navigation ) 是由 胡小波 杨业 叶华 于 2019-10-24 设计创作，主要内容包括：本发明实施例公开了一种激光雷达与组合惯导的位姿标定方法、系统及介质。其中,该方法包括：获取激光雷达和组合惯导在两个采集位置对多个标定板采集的两个点云数据集和两个惯导数据集,所述激光雷达和所述组合惯导刚性连接；根据所述两个点云数据集,确定各个标定板的参考点在所述两个点云数据集中对应的点云坐标；根据所述两个惯导数据集和各个标定板的参考点在所述两个点云数据集中对应的点云坐标,确定所述激光雷达到所述组合惯导的位姿转换矩阵。本发明的技术方案无需人工测量,可快速准确的标定出激光雷达和组合惯导之间的相对位姿。(The embodiment of the invention discloses a method, a system and a medium for calibrating the pose of a laser radar and a combined inertial navigation system. Wherein, the method comprises the following steps: acquiring two point cloud data sets and two inertial navigation data sets acquired by a laser radar and a combined inertial navigation on a plurality of calibration plates at two acquisition positions, wherein the laser radar is rigidly connected with the combined inertial navigation; determining point cloud coordinates corresponding to the reference points of the calibration plates in the two point cloud data sets according to the two point cloud data sets; and determining a pose transformation matrix of the laser radar reaching the combined inertial navigation according to the two inertial navigation data sets and the corresponding point cloud coordinates of the reference point of each calibration plate in the two point cloud data sets. According to the technical scheme, manual measurement is not needed, and the relative pose between the laser radar and the combined inertial navigation can be calibrated quickly and accurately.)

1. A pose calibration method of a laser radar and a combined inertial navigation is characterized by comprising the following steps:

acquiring two point cloud data sets and two inertial navigation data sets acquired by a laser radar and a combined inertial navigation on a plurality of calibration plates at two acquisition positions, wherein the laser radar is rigidly connected with the combined inertial navigation;

determining point cloud coordinates corresponding to the reference points of the calibration plates in the two point cloud data sets according to the two point cloud data sets;

and determining a pose transformation matrix of the laser radar reaching the combined inertial navigation according to the two inertial navigation data sets and the corresponding point cloud coordinates of the reference point of each calibration plate in the two point cloud data sets.

2. The method of claim 1, wherein determining, from the two point cloud data sets, corresponding point cloud coordinates of the reference point of each calibration plate in the two point cloud data sets comprises:

for each point cloud data set, converting a three-dimensional plane corresponding to the point cloud data set into a two-dimensional plane, and determining a spatial conversion matrix corresponding to the point cloud data set in the conversion process;

determining two-dimensional coordinates corresponding to the reference points of the calibration plates in the two-dimensional plane;

and determining the point cloud coordinates corresponding to the reference points of the calibration plates in the three-dimensional plane of the point cloud data set according to the space conversion matrix and the two-dimensional coordinates.

3. The method of claim 2, wherein converting the three-dimensional plane corresponding to the point cloud dataset into a two-dimensional plane comprises:

fitting a three-dimensional plane equation corresponding to the point cloud data set;

determining a normal vector of the three-dimensional plane equation according to the three-dimensional plane equation;

and rotating the three-dimensional plane corresponding to the three-dimensional plane equation so as to enable the normal vector of the three-dimensional plane to coincide with a preselected coordinate axis in the rectangular coordinate system.

4. The method according to claim 2, wherein each calibration plate is composed of a group of main calibration plates and auxiliary calibration plates with different reflectivity and coincident centers, each group of main calibration plates and auxiliary calibration plates are arranged in parallel, and the projection outline of each group of main calibration plates on the auxiliary calibration plates is contained in the outline of the auxiliary calibration plates;

correspondingly, if the reference point is the central point of the calibration board, determining the corresponding two-dimensional coordinates of the reference point of each calibration board in the two-dimensional plane, including:

determining the outline of the main calibration plate of each calibration plate in the two-dimensional plane according to the point cloud data of each calibration plate in the two-dimensional plane;

and fitting the corresponding two-dimensional coordinates of the central points of the calibration plates in the two-dimensional plane according to the profiles of the main calibration plates of the calibration plates in the two-dimensional plane.

5. The method of claim 1, wherein determining a pose transformation matrix of the laser radar to the combined inertial navigation according to corresponding point cloud coordinates of the reference points of the two inertial navigation data sets and the respective calibration plates in the two point cloud data sets comprises:

generating a first world coordinate expression corresponding to a reference point of a target calibration plate at a second acquisition position according to the two inertial navigation data sets and a pose transformation matrix of the combined inertial navigation reached by the laser radar to be determined; wherein the target calibration plate is any one of the plurality of calibration plates;

generating a second world coordinate expression corresponding to the reference point of the target calibration plate at the second acquisition position according to the point cloud coordinates corresponding to the reference point of each calibration plate in the two point cloud data sets;

determining a pose transformation matrix of the laser radar reaching the combined inertial navigation according to the first world coordinate expression and the second world coordinate expression;

and the second acquisition position is the position of the point cloud data set and the inertial navigation data set acquired for the second time in the two acquisition positions.

6. The method of claim 5, wherein generating a first world coordinate expression of a reference point of a target calibration plate corresponding to a second acquisition position according to the two inertial navigation data sets and a pose transformation matrix of the combined inertial navigation reached by the laser radar to be determined comprises:

determining an inertial navigation conversion matrix of the combined inertial navigation from a first acquisition position to a second acquisition position according to the two inertial navigation data sets;

and generating a first world coordinate expression of converting the reference point of the target calibration plate from the radar coordinate system to a world coordinate system at the second acquisition position according to the inertial navigation conversion matrix, the pose conversion matrix of the combined inertial navigation to be determined, and the point cloud coordinate corresponding to the reference point of the target calibration plate in the point cloud data set acquired at the second acquisition position.

7. The method of claim 5, wherein generating a second world coordinate expression of the target calibration plate corresponding to the reference point at the second acquisition location according to the corresponding point cloud coordinates of the reference point of each calibration plate in the two point cloud data sets comprises:

determining a point cloud transformation matrix of the point cloud data from a first acquisition position to a second acquisition position according to corresponding point cloud coordinates of the reference point of each calibration plate in the two point cloud data sets;

and generating a second world coordinate expression of converting the reference point of the target calibration plate from the radar coordinate system to a world coordinate system at the second acquisition position according to the point cloud transformation matrix and the corresponding point cloud coordinate of the reference point of the target calibration plate in the point cloud data set acquired at the second acquisition position.

8. The method of claim 5, wherein determining the pose transformation matrix of the laser radar to the combined inertial navigation based on the first world coordinate expression and the second world coordinate expression comprises:

constructing a target equation according to the first world coordinate expression and the second world coordinate expression;

and solving the target equation to obtain a pose transformation matrix from the laser radar to the combined inertial navigation.

9. A surveying and mapping system is characterized by comprising a laser radar, a combined inertial navigation and control device; the control device is respectively connected with the laser radar and the combined inertial navigation system, and comprises:

one or more processors;

storage means for storing one or more programs;

when executed by the one or more processors, cause the one or more processors to implement the method for pose calibration of lidar and combined inertial navigation according to any of claims 1-8.

10. A computer-readable storage medium, on which a computer program is stored, wherein the program, when executed by a processor, implements the method for pose calibration of lidar and combined inertial navigation according to any one of claims 1 to 8.

Technical Field

The embodiment of the invention relates to the technical field of computers, in particular to a method, a system and a medium for calibrating the pose of a laser radar and a combined inertial navigation system.

Background

With the development of sensor technology, in the field of outdoor 3D mapping and positioning, the combined use of the multi-line laser radar and the combined inertial navigation becomes an indispensable scheme in multi-sensor fusion. The calibration of the relative pose between the two is crucial to the use of the sensor, and is directly related to the accuracy of the measurement result of the sensor.

At present, when the pose calibration of the laser radar and the combined inertial navigation is carried out, the method is adopted to manually measure the angle value and the displacement value between the laser radar and the combined inertial navigation which are in rigid connection, and further realize the pose calibration of the laser radar and the combined inertial navigation according to the measurement result. However, the relative pose between the laser radar and the combined inertial navigation is calibrated through manual measurement, so that the cost is high, the error is large, and the accuracy of pose calibration is seriously influenced.

Disclosure of Invention

The embodiment of the invention provides a method, a system and a medium for calibrating the pose of a laser radar and a combined inertial navigation system, which can quickly and accurately calibrate the relative pose between the laser radar and the combined inertial navigation system without manual measurement.

In a first aspect, an embodiment of the present invention provides a pose calibration method for a laser radar and a combined inertial navigation, including:

acquiring two point cloud data sets and two inertial navigation data sets acquired by a laser radar and a combined inertial navigation on a plurality of calibration plates at two acquisition positions, wherein the laser radar is rigidly connected with the combined inertial navigation;

determining point cloud coordinates corresponding to the reference points of the calibration plates in the two point cloud data sets according to the two point cloud data sets;

and determining a pose transformation matrix of the laser radar reaching the combined inertial navigation according to the two inertial navigation data sets and the corresponding point cloud coordinates of the reference point of each calibration plate in the two point cloud data sets.

In a second aspect, an embodiment of the present invention further provides a pose calibration apparatus for a laser radar and a combined inertial navigation, where the apparatus includes:

the system comprises a data set acquisition module, a data set acquisition module and a data set processing module, wherein the data set acquisition module is used for acquiring two point cloud data sets and two inertial navigation data sets acquired by a laser radar and a combined inertial navigation on a plurality of calibration plates at two acquisition positions, and the laser radar is rigidly connected with the combined inertial navigation;

the point cloud coordinate determination module is used for determining point cloud coordinates corresponding to the reference points of the calibration plates in the two point cloud data sets according to the two point cloud data sets;

and the pose conversion matrix determining module is used for determining a pose conversion matrix of the laser radar reaching the combined inertial navigation according to the two inertial navigation data sets and the corresponding point cloud coordinates of the reference point of each calibration plate in the two point cloud data sets.

In a third aspect, an embodiment of the present invention further provides a mapping system, where the mapping system includes a laser radar, a combined inertial navigation and control device; the control device is respectively connected with the laser radar and the combined inertial navigation system, and comprises:

one or more processors;

storage means for storing one or more programs;

when the one or more programs are executed by the one or more processors, the one or more processors implement the method for calibrating the pose of lidar and combined inertial navigation according to the first aspect.

In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the method for calibrating the pose of the lidar and the combined inertial navigation according to the first aspect is implemented.

According to the method, the system and the medium for calibrating the pose of the laser radar and the combined inertial navigation, provided by the embodiment of the invention, two point cloud data sets and two inertial navigation data sets, which are acquired by the laser radar and the combined inertial navigation at two different positions aiming at a plurality of calibration plates in a rigid connection manner, point cloud coordinates corresponding to reference points of each calibration plate in each point cloud data set are determined through the two acquired point cloud data sets, and then a pose conversion matrix from the laser radar to the combined inertial navigation is determined by combining the two inertial navigation data sets, so that the relative pose between the laser radar and the combined inertial navigation can be accurately calibrated. According to the scheme of the embodiment of the invention, manual measurement is not needed in the whole process of calibrating the relative poses of the laser radar and the combined inertial navigation, the accuracy of the calibration result is greatly improved, and the calibration cost is reduced. A new idea is provided for calibrating the relative pose between the laser radar and the combined inertial navigation.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1A is a flowchart of a pose calibration method for a laser radar and a combined inertial navigation system according to a first embodiment of the present invention;

FIG. 1B is a schematic diagram of a data acquisition process of a lidar and a combined inertial navigation system according to an embodiment of the invention;

fig. 2A is a flowchart of a pose calibration method for a laser radar and a combined inertial navigation system according to a second embodiment of the present invention;

fig. 2B is a visual image effect diagram of a calibration plate structure and two-dimensional point cloud data thereof in the embodiment of the present invention;

FIG. 3 is a flowchart of a pose calibration method for a laser radar and a combined inertial navigation system according to a third embodiment of the present invention;

fig. 4 is a schematic structural diagram of a pose calibration apparatus for a laser radar and a combined inertial navigation in a fourth embodiment of the present invention;

fig. 5A is a schematic structural diagram of a mapping system according to a fifth embodiment of the present invention;

fig. 5B is a schematic structural diagram of a control device of a mapping system according to a fifth embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present invention, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.