Friction compensation for 6DOF Cartesian coordinate haptic interface

In this paper, control schemes for haptic interface for micromanipulation systems is mainly discussed. We have proposed a tele-micromanipulation system, which enables human operators to operate micro tasks, such as assembly or manufacturing, without feeling stress. This paper focuses on the haptic sense, which gives the operators the feeling of presence. The mechanical instrument applied in the human interface device usually has a reasonable immanent friction. This friction must be compensated in a way that the operator should not feel this friction force but the force from the manipulated environment. The main contribution of this paper is a direct model based chattering free sliding mode friction estimator and compensator for a mechanical instrument. Experimental results are presented.