Force Control for Grasping Soft Tissue

Abstract

Abstract – Tissue grasping is a crucial component of surgical procedures that involves simultaneously satisfying two competing criteria – maintaining grasp stability while avoiding damage due to excessive grip force. Automation of grasp force control thus requires a controller to apply grasping forces just sufficient to maintain grasp stability. This task is complicated by the serially connected dynamics of grasp friction and tissue relaxation. This paper presents a preliminary experimental investigation of a simple model-independent approach to grasp control based on (i) measurement of total tangential grasp force and (ii) discrimination of relaxation and friction forces by imposing a limited basis set of grasper motions. † Index Terms – grasping; soft tissue; robotics; surgery I.