Magnetic actuation of hinged microstructures

We have investigated magnetic actuation of hinged, surface micromachined structures. Electroplated magnetic material (Permalloy) is integrated with two types of hinged microstructures and the magnetic actuation process has been experimentally characterized. Under a given external magnetic field, the angular displacement of a hinged structure is determined by the volume of the magnetic material or by the stiffness of an auxiliary flexural loading spring. We have demonstrated parallel actuation of large arrays of hinged microstructures under a global (wafer scale) external magnetic field. The design rules for achieving a prescribed asynchronous actuation sequence among a group of microstructures have been determined to enable efficient parallel assembly of three-dimensional (3-D) microstructures.