PMD Camera- and Hand-Eye-Calibration for On-Orbit Servicing Test Scenarios on the Ground

Abstract

In this paper we present the ability to intrinsically and extrinsically calibrate a Time-of-Flight sensor, namely, a Photonic Mixer Device (PMD) camera, using the DLR CalDe and DLR CalLab camera calibration toolbox. This camera is intended as a visual sensor for pose estimation in the close rendezvous phase during future On-Orbit servicing. In order to test and verify the pose estimation algorithms on the ground, we conduct different rendezvous scenarios using the European Proximity Operation Simulator. It is necessary to accurately know intrinsic parameters like the focal length, the principal point, and the distortion parameters, as well as the extrinsic parameters, i.e., the position and orientation of the PMD camera relating to the mounting board, whenever it is fixed on the robot and involved in the process of target pose estimation. In this work we differentiate from state-of-the-art approaches for the calibration of PMD cameras in this context by making use of the motion of the mounting robotic manipulator alone, i.e., without the need for accurate positioning of the target calibration plate by a second robotic manipulator.