Analysis and Modeling of a Voice-Coil Linear Vibration Motor Using the Method of Images

The vibration motors for smart phones with haptic interfaces require higher reaction rate and longer service life than what a typical rotational motor with eccentric mass provides. In this paper, a new type of a linear vibration motor is proposed. A voice-coil actuator is employed for high reaction rate. Permanent magnets replace mechanical springs, which would help increase the service life. For analyzing and modeling the proposed vibration motor, we use the method of equivalent current sheet and the method of images. These methods are validated against finite element analyses and experiments. A prototype motor is designed and fabricated. Tests with the prototype show the feasibility of the proposed linear vibration motor.