Development of an elementary micromachined electromagnetic digital actuator for microdisplacements

In this paper an elementary micromachined digital electromagnetic actuator for microdisplacements is presented. The moving part is composed of a permanent magnet placed in a silicon square cavity. This magnet can reach 4 discrete positions and can be switched by applying current pulses through wires placed below the cavity. A semi-analytical model has been developed to design the actuator. A prototype, composed of a silicon part, has been manufactured using Deep Reactive Ion Etching (DRIE) process. The device has been characterized by several performance tests: the response time is 8 ms and the measured stroke is 179 µm.