Development of forceps manipulator for assisting laparoscopic surgery

Abstract

Telemanipulation for use in surgery is an increasing field of robotics which combines new technical and medical developments. Some drawbacks of minimally invasive surgery can be reduced by using telemanipulation systems. This article describes the development of a hydraulic gripper with force-feedback which is designed for use in laparoscopic surgery. With respect to the manipulation of bowels during a colon resection a gripper is designed which exerts a force with a significantly better distribution on the tissue compared to conventional grippers. This is done by a flexible tube which curls itself around the tissue (like the finger of a surgeon by open surgery) and prevents damaging due to the absence of sharp (metal) edges. The force exerted on the tissue is measured by the pressure of the water in the tube and used to control the driving system of the forceps. Using a computer system, the force exerted on the tissue can be limited to a certain amount by a control algorithm. The driving system consists of an electromotor with spindle and a piston and is driven directly by the computer. Finally, a telemanipulation system is presented, which consists of the hydraulic forceps, a transputer network and a master manipulator with force actuation. With this instrument the surgeon can drive the forceps to a desired force, which is directly presented to his finger. Future developments include the positioning of the gripper inside its working area.