Position and force control of a flexible robot manipulator for orthopedic surgery

Abstract

Surgeons are using robots as a tool to increase surgery accuracy and decrease procedure times. One of the main problems in robotic assisted orthopedic surgery is the force control in manipulator robots. It always has been subject of great study and interest in the scientific community, where the most common approach is to consider it as a hybrid control problem, due to their complexity and non-linearities. It becomes evident, when we consider two distinct states, the pre-contact state and after contact state. In order to have faster motion and better acceptance by the surgeons the manipulator must be lightweight and therefore may vibrate. The flexible manipulator used in this study contains two flexible links, one rigid link and six revolution joints, all actuating under gravity effect. The manipulator robot control strategies are based on the Closed-Loop Inverse Kinematics algorithm (CLIK) and Linear Quadratic Regulator control (LQR).