Mechanical design of a 5-DOF robotic interface for application in haptic simulation systems of large-organ laparoscopic surgery

Laparoscopic manipulation of delicate large intra-abdominal organs is a difficult task that needs special training programs to improve the surgeons’ dexterity. In this study, the mechanical design of a robotic interface for haptic simulation of large-organ laparoscopic surgery is described. The designed robot enjoys five active DOFs, back drivability, low inertia, friction and backlash, and sufficiently large force/moment production capacity. The kinematics of the robot was analyzed and a functional prototype was fabricated for experimental tests. Results indicated that the target workspace was fully covered with no singular points inside. The mechanism was highly isotropic and the torque requirements were in the acceptable range. The trajectory tracking experiments against a 1 kg payload revealed an RMS of 0.9 mm, due to the simplifications of the kinematic model, i.e., not considering the friction and backlash effects. It was concluded that the designed robot could satisfy the mechanical requirements for being used as the robotic interface in a haptic large-organ laparoscopic surgery simulation system.