Multiple-robot programming for coordinated motion, end-effector calibration, and part localization

The authors present an algorithmic solution to the problem of programming a redundant multiple-robot system for concurrent motion. Arc welding processes are used as application examples. Specifically, the weld path programming algorithm is illustrated, using the GTAW (gas tungsten arc welding) process as an example and assuming a 6-DOF (six-degree-of-freedom) welding robot and a 2-DOF positioner. The algorithm is designed to simplify, and to some extent automate, the task of programming the robotic mechanisms of the welding workcell. The algorithm treats the multiple robots as a single kinematic mechanism. Redundant joints are used to satisfy constraints imposed by the welding process. Approaches to solving the practical problems of calibration and localization are presented within the framework of the algorithm. Simulation examples for specific tasks are demonstrated and discussed. >