Force control of a new 6-DOF haptic interface for a 6-DOF serial robot

This paper presents force control systems of a new 6-DOF haptic interface for a 6-DOF serial robot. The haptic interface was designed to operate with three translations and three rotations. First open loop force control is implemented to demonstrate the feed forward static force control based on Jacobian matrix. The error of open loop control can be reduced by a PD controller. However this controller does not show good performance if the forces change directions rapidly. In addition the joint frictions and dynamics degrades the controller performance. Therefore a self-tuning fuzzy PD controller is designed to adjust the parameters of PD controller. Finally a master-slave control system for the haptic interface and serial robot is presented.