EXTRINSIC CALIBRATION OF ROTATING 2D LASER RANGE FINDER AND CAMERA USING PHOTOGRAMMETRIC TEST FIELD AND PING PONG BALLS
Keywords: Extrinsic Calibration, 2D Laser Range Finder, Camera, Spherical Targets, Bundle Adjustment
Abstract. In this article, a method for the extrinsic calibration of a 2D laser range finder and a camera is presented. This technique produces a 3D point cloud from the test field by connecting a laser range finder to a servomotor. In this study, ping balls and standard photogrammetric targets were employed as a test field. Ping pong balls are used because they can be easily recognized in data from laser range finder and camera. To calculate extrinsic calibration parameters between a camera and laser range finder, these balls are employed as control points in the data. The extrinsic calibration of the Laser range finder and camera is carried out using the point cloud created from the test field and the photos captured from the test field. In this method, a sphere is fitted to each ping pong ball's points in the 3D point cloud, and the coordinates of that sphere's center are taken to be the coordinates of that ball. By measuring the distances between various targets in the test field, the scale can be resolved. This approach was compared with another state-of-the-art method. The proposed method is more accurate and stable than the alternative way, taking into account the average inaccuracy of check points.