Improvements of force tracking performances for a minimal surgery training system using haptic and robot devices

This paper presents the closed loop teleoperation of a minimal surgery training system using haptic and robot devices. The force tracking performances of system can be improved by using dynamic compensation and fuzzy control. In this system, the master is the 6-DOF haptic device and the slave is the 6-DOF serial robot. The master haptic device provides the trajectories for the slave serial robot throught the operation of user's hand on the steering handle while the slave robot sends feedback forces on its end effector to the master controller in order to generate forces/moments on the steering handle of haptic master. In this manner the user's hand will feel the forces/moments as the same those of the robot end effector. Because dynamics of the master haptic device affects directly to the performances of control actions, it should be calculated to compensate in the control algorithms. Inverse dynamics combined with fuzzy control is used to compensate for actual dynamics of the haptic master in the real closed loop teleoperation system. Experiment results indicate that the dynamic compensation and fuzzy control can improve the control performances effectively.