On the development of a portable, cost effective and compact master/slave system for robot-assistec Minimally Invasive Surgery

Abstract

Making robot's joint compliant is an interesting design paradigm for achieving safe Human Robot (HR) collaboration. Until now the researchers focus has mainly been on revolute joint, in contrast to a few works on prismatic joint. This work introduces a new design capable of achieving, passively, a nonlinear elastic behavior for prismatic joint implementation that we refer to as Prismatic Compliant Joint (PCJ). This new device is based on a six-bar mechanism equipped with a linear spring. Hence, this structure generates the desired nonlinear stiffness behavior under a specified external force. The elasticity characteristic complies with Hunt-Crossley (HC) contact model derived from the conducted experimental work on the human abdomen. Furthermore, a simulation of HR collision is performed in order to verify the shock absorption capacity of the PCJ on the rigid skull. Finally, a 3D printed prototype is presented as a proof of concept of the mechanical feasibility of the desired behavior.