Geometry-based robot calibration method

This paper describes a geometry-based robot calibration method for a 6-DOF robot manipulator. The calibration device only includes a set of light projections consisting of three laser beams. In the proposed calibration algorithm, the coordinates of the laser spots on the table in the world coordinate system is first obtained by processing the image data from a CCD camera fixed above. Based on that, the mapping between the world coordinate system and the robot base coordinate system can then be utilized to locate the robot within its environment by some geometric analysis. The calibration method proposed in the paper is extremely suitable for the fast calibration of a multi-robot cooperation system due to the low cost of the calibration device and the simplicity of the algorithm involved. Some experimental results for a RH6 robot are presented to demonstrate the validity of the proposed calibration method.