Design and Optimization of a Voice Coil Motor With a Rotary Actuator for an Ultrasound Scanner

This paper proposes a new application for the rotary voice coil motor (VCM). In developing a low-cost ultrasound scanner for the developing world, an oscillating transducer is required to sweep over the skin. The ultrasound scanner must operate from a USB power supply in remote locations. The application requires a 3.3-N force on the coils of the motor to overcome the inertia of the skin. A proof-of-concept prototype motor with electronics has been designed, simulated, and tested. The VCM optimization is discussed in detail with the unique separation of the magnets being critical to reduce the axial bearing forces for this application.