Identifying the kinematics of robots and their tasks

An approach to identifying the kinematic models of manipulators and their task geometry is presented. Starting with the observation that in many tasks manipulators naturally form mobile closed kinematic chains, it is shown that these closed loops can be identified by an iterative least-squares algorithm similar to that used in calibrating open chain manipulators. By merely using joint angle readings and self motions, consistency conditions can be utilized to identify the kinematic parameters. While the task of a robot opening a door is studied in detail, the method readily generalizes to a large class of robot tasks. Simulations are presented to accompany the analysis