Design and Kinematics Analysis of Parallel Robotic Arm for Urological Surgery

Abstract

In this paper, a novel 4-DOF parallel surgical robot with parallelogram remote center-of-motion mechanism is proposed for transurethral resection of bladder tumors in urology. The emergence of minimally invasive surgery robots has enabled surgeons to achieve more dexterous and more reliable surgical procedures, but general surgical robot platforms have some shortcomings, such as high cost and complicated maintenance, which is not conducive to promotion in a wide range. Based on analysis of the manual operation characteristics of the surgeons in the current operation, the kinematics model of the surgical tool with D-H coordinates is established, and the Jacobian matrix of the cutting points in the instantaneous motion analysis is solved. A robotic arm scheme, including parallelogram remote center-of-motion mechanism, rope drive module and parallel actuator module, is designed. A kinematic model of the surgical robot is established. A calculation method of Jacobian matrix with numerical methods is provided. The Kinematic Conditioning Index defined to measure the operational dexterity of the robot in the global and local space is described. With the index as the optimization goal, optimized selection of parameters and configurations are performed. And the final physical model of surgical robot is shown. The novel surgical robot system can maintain good surgical performance, while greatly reducing system development costs and complexity.