In this paper, a compliant motion control system for a redundant manipulator, based on the model-based collision detection system[l] is proposed. First, we discuss the collision detection sensitivity of the model-based collision detection system and do a case study for a 7-DOF serial link manipulator to discuss the validity of the collision detection system. Then, we propose a compliant motion control system for the 7-DOF manipulator taking the result of the sensitivity analysis into account. The ann angle of the 7-DOF manipulator, which is a redundant degree of freedom of the manipulator, is controlled compliant to the external force applied by the collision and estimated by the colIision detection system. The proposed compliant motion control system is implemented in the 7-DOF manipulator and the experimental results illustrate the validity of the proposed system.

In this paper, we propose a collision detection system based on a nonlinear adaptive impedance control law. The collision detection detects collisions of a manipulator with its environment without using external sensors. The adaptive impedance control law is employed to estimate the dynamic parameters of the manipulators, and allows the manipulator to have interaction with its environment. The system detects collisions based on the difference between the actual input torque to the manipulator and the reference input torque, which is calculated based on the estimated parameters of the manipulator dynamics. The manipulator stops when a collision detection system is implemented in an industrial manipulator and experimental results illustrate the validity of the proposed system.