Augmented Model of the 3-PRS Manipulator for Kinematic Calibration

Kinematic calibration helps improve the accuracy on any manipulator whereas an extended kinematic model will help even further by providing a closer kinematic representation of the physical manipulator. In this paper an augmented kinematic model of the 3-PRS manipulator is developed. The original architecture and kinematics of the manipulator are presented. The revised kinematic model is then presented, followed by a derivation of the new inverse and forward displacement solutions. Simulation results show that the augmented model improves the accuracy of the manipulator by several orders of magnitude assuming even moderate deviations from the nominal kinematic model.