Tracking controls of torque and force of 4-degree-of-freedom haptic master featuring smart electrorheological fluid

This study presents a new type of haptic master device using electrorheological fluid for minimally invasive surgery application. The proposed haptic master consists of an electrorheological spherical haptic device for 3-degree-of-freedom rotational motion and an electrorheological linear haptic device for 1-degree-of-freedom translational motion. The principal design variables of the haptic master are determined using the Bingham characteristic of electrorheological fluid and geometrical constraints. After designing an organ model, control performances are evaluated in a virtual environment using a sliding mode controller. It is demonstrated that the proposed haptic master can track well both torque and force which are required (or desired) ones for surgical operation using the robot-assisted minimally invasive surgery.