Portable Forceps Manipulator with Closed Loop Mechanism using Gimbal-mounted Parallel Linkage for Endoscopic Surgery

Abstract

A new locally operated detachable end-effector manipulator (LODEM) as the portable forceps robot that can be used by a surgeon as a third arm during laparoscopic surgery was developed. The portable forceps manipulator which has motor controlled three DOFs consists of a separable pivot restraint device that can be sterilized and an actuator unit draped with a sterilized cover. This manipulator uses a gimbal-mounted parallel linkage mechanism of the closed loop structure for the pitch and the yaw axes, and a wire driven linear slider mechanism for the insertion axis attached to the forceps. The manipulator placed above the abdominal wall using a fixed arm connected to a bed rail is motor controlled by a handheld interface with button switches. The positional accuracy and the mechanical deflection of the manipulator were evaluated. Simulated laparoscopic cholecystectomy using the prototype manipulator was performed on a surgically realistic gall bladder model. It was confirmed that the organ model could be pulled in various directions using the forceps attached to the manipulator manually and driven by the motors. The results of the present study indicate that the proposed manipulator could be used for robotically assisted laparoscopic surgery by a surgeon working near the patient.