Design and Implementation of a PWM-Controlled Controllable Current Source for Robotic Catheter Force Feedback Applications

In recent years, force sensing and drive control at the distal end of the ablation catheter in radiofrequency ablation (RFA) surgery has received widespread attention. In particular, how to achieve high-precision catheter operation has become a hot research issue. In order to solve this problem, this paper proposes a controllable current source based on pulse width modulation (PWM) control for a robotic ablation catheter force feedback system. The system adjusts the magnetic field strength of the magnetorheological fluid through a Buck converter to achieve force feedback control during catheter operation. The design focuses on fast response, a wide current adjustment range, excellent stability, and compact design to ensure that the system can work stably in a medical environment. Through experimental verification, the designed current source shows good dynamic response and precise force feedback adjustment when controlling force feedback, which significantly improves the operation accuracy and safety of the catheter.