Extrinsic Calibration of a Monocular Camera and a Single Line Scanning Lidar

This paper proposes a calibration method for monocular cameras and 2D Lidar external parameters based on automatic detection of features. The triangle calibration target is used, and the point and line features are automatically extracted. The point line constraint and the proposed European transformation invariance constraint are applied simultaneously in the calibration process to obtain more accurate and effective external parameters. First, a line feature extraction method is proposed. The triangle region in the image is extracted by Hough transform and K-means clustering, and the 3D pose of the triangle calibration target is calculated. Second, we analyze the effects of image feature extraction and Lidar measurement range errors on rotating and translational external parameters, respectively, through simulation experiments. The error characteristics of camera-lidar external parameters are analyzed and compared with those of Zhang and Pless. Finally, real-data experiments show that our method can obtain accurate external calibration.