This paper describes the process of calibrating the kinematic model for an active binocular head having four revolute joints and two prismatic joints. We use the complete and parametrically continuous (CPC) model proposed by Zhuang and Roth in 1990 to model the motorized head (or camera positioning system), and use a closed form solution to identify its CPC kinematic parameters. The calibration procedure is divided into two stages. In the first stage, the two cameras are replaced by two end-effector calibration plates each having nine circles. The two removed cameras can be used to build a stereo vision system for observing the varying positions and orientations of the end-effector calibration plates when moving the joints of the head. The positions and orientations of the calibration plates, or equivalently, of the end-effectors, can be determined from the stereo measurements. The acquired data are then used to calibrate the kinematic parameters. In the second stage, the cameras are remounted to the IIS-head, and a method proposed by Tsai is used to calibrate the hand-eye relation. Once the above kinematics calibration is done, the binocular head can be controlled to gaze or track 3-D targets.

Date Published: 1 November 1992
PDF: 15 pages
Proc. SPIE 1825, Intelligent Robots and Computer Vision XI: Algorithms, Techniques, and Active Vision, (1 November 1992);

Published in SPIE Proceedings Vol. 1825:
Intelligent Robots and Computer Vision XI: Algorithms, Techniques, and Active Vision
David P. Casasent, Editor(s)