Abstract

Info

Title:: Controlling contact force in robot-assisted cranio-maxillofacial surgery using fuzzy variable admittance

Author(s):: WANG Zehua; HU Zhi; LU Weiming; NI Shuangtao; School of Electronic and Electrical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China

Keywords:: Keywords: surgical robot admittance control fuzzy control contact force control

Abstract:: Abstract: A robot force control method based on fuzzy variable admittance is proposed for solving the problem of poor force control caused by unstable environmental parameters during robot-assisted cranio-maxillofacial surgery. The detection of the contact force is realized by a force sensor installed at the end of UR5 robot, and the appropriate expected force is set. According to the changes in environmental parameters, the admittance control model is automatically adjusted and the expected force is tracked. Finally, contact force tracking and position error simulation analysis are carried out, and force control experiments is conducted to verify the effectiveness of the control method during the operation process of robot-assisted pulling apart the simulated maxillofacial tissues. The results show that in a dynamic time-varying surgical environment, the fuzzy variable admittance control method can achieve the ideal force control, reducing peak contact force by 10.77%, reducing the number of system oscillations by 50%, and shortening the stable adjustment time by 18.75%. To some extent, the proposed method can avoid the injury caused by excessive contact force and meet the safety requirements of surgery.