The effective kinematic calibration method of industrial manipulators using IGPS

In this paper, presented is an effective kinematic calibration method for serial robot manipulators which are six joints welding robots used by SHI (Samsung Heavy Industries). The robot endpoint's position and orientation are measured by the IGPS (indoor global positioning system). This paper capitalizes on the modified D-H (Denavit and Hartenberg) parameters for kinematic error modeling, and estimates all kinematic parameters through the least square method that is minimize a kinematic position error. This work also presents the comparison of the robot position and orientation error between after and before calibration that is applied joint offset in the commercial controller.