Fuzzy PID Control Orienting Medical Robot in Minimally Invasive Surgery

Radio frequency ablation is a simple, safe and potentially effective treatment for patients with liver tumor. Despite all recent therapeutic advancements, however, intra-procedural target localization and precise and consistent placement of the tissue ablator device are still unsolved problems. Therefore, we study robot-assisted radio frequency ablation of liver tumors that typically require precise placement of the ablator tool to meet the predefined planning and lead to efficient tumor destruction. But, it is very difficult for the robot arm to track moving target in real-time and accuracy, because the moving target moves in nonlinear and uncertainty. This paper proposes a new method of fuzzy PID controller combining the performance of fuzzy controller and PID controller. Fuzzy controller is applied to track the target moving in mutation, PID controller is applied to improve dynamic performance. The experimental results have showed that the control system has strong robustness.