To obtain high-precision measurement data using vehicle-borne light detection and ranging (LiDAR) scanning (VLS) systems, calibration is necessary before a data acquisition mission. Thus, a novel calibration method based on a homemade target ball is proposed to estimate the system mounting parameters, which refer to the rotational and translational offsets between the LiDAR sensor and inertial measurement unit (IMU) orientation and position. Firstly, the spherical point cloud is fitted into a sphere to extract the coordinates of the centre, and each scan line on the sphere is fitted into a section of the sphere to calculate the distance ratio from the centre to the nearest two sections, and the attitude and trajectory parameters of the centre are calculated by linear interpolation. Then, the real coordinates of the centre of the sphere are calculated by measuring the coordinates of the reflector directly above the target ball with the total station. Finally, three rotation parameters and three translation parameters are calculated by two least-squares adjustments. Comparisons of the point cloud before and after calibration and the calibrated point clouds with the point cloud obtained by the terrestrial laser scanner show that the accuracy significantly improved after calibration. The experiment indicates that the calibration method based on the homemade target ball can effectively improve the accuracy of the point cloud, which can promote VLS development and applications.

中文翻译：

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自行开发的车载式LiDAR扫描系统的准确校准

为了使用车载光检测和测距（LiDAR）扫描（VLS）系统获得高精度的测量数据，在执行数据采集任务之前必须进行校准。因此，提出了一种基于自制目标球的新型校准方法来估计系统安装参数，该参数是指LiDAR传感器与惯性测量单元（IMU）方向和位置之间的旋转和平移偏移。首先，将球面点云拟合到一个球体中以提取中心坐标，然后将球体上的每条扫描线拟合到该球体的一部分中，以计算从中心到最近的两个部分的距离比，通过线性插值计算中心的姿态和轨迹参数。然后，球心的真实坐标是通过全站仪测量目标球正上方的反射镜的坐标来计算的。最后，通过两个最小二乘平差计算三个旋转参数和三个平移参数。校准前后的点云与校准后的点云与地面激光扫描仪获得的点云的比较表明，校准后精度显着提高。实验表明，基于自制目标球的标定方法可以有效地提高点云的精度，可以促进VLS的发展和应用。通过两个最小二乘平差计算三个旋转参数和三个平移参数。校准前后的点云与校准后的点云与地面激光扫描仪获得的点云的比较表明，校准后精度显着提高。实验表明，基于自制目标球的标定方法可以有效地提高点云的精度，可以促进VLS的发展和应用。通过两个最小二乘平差计算三个旋转参数和三个平移参数。校准前后的点云与校准后的点云与地面激光扫描仪获得的点云的比较表明，校准后精度显着提高。实验表明，基于自制目标球的标定方法可以有效地提高点云的精度，可以促进VLS的发展和应用。