Magnetic-Free Wireless Self-Direct Drive Motor System for Biomedical Applications With High-Robustness

The integration of high-precision robotics and magnetic resonance imaging (MRI) exhibits the potential to enhance the accuracy and safety of MRI image-guided surgery. However, the potential hazards associated with conventional electromagnetic servomotors in strong magnetic fields have hindered the development of MRI-compatible robotics. To address this issue, this article proposes and implements a novel magnetic-free wireless drive system that creatively integrates capacitive power transfer with ultrasonic motors to realize the truly wireless self-direct drive without strong magnetic field interference. The proposed system overcomes the drawbacks of existing wireless motors requiring microcontrollers, power switches and communication modules at the motor side, facilitating high-degree integration and maintenance-free operation. In addition, a dual-mode wireless drive control scheme is proposed to achieve the full-speed range wireless direct drive. Promisingly, the proposed system is unaffected by coupling mechanism misalignment and load variation, ensuring precise manipulation with high robustness. Both theoretical analysis and experimental results are conducted to verify the effectiveness of the proposed wireless motor system.