Out-of-plane magnetic actuators with electroplated permalloy for fluid dynamics control

We have developed millimeter-scaled magnetic actuators capable of achieving large out-of-plane displacement and large forces using surface micromachining techniques in conjunction with electroplating of Permalloy (Ni₈₀Fe₂₀). Each actuator consists of a Permalloy piece attached to flexural cantilever beams, which are 400 μm long and 100 μm wide. Experiments show that under a 6×10⁴ A/m external magnetic field, an actuator with the volume of the magnetic piece being 1 mm×1 mm×5 μm can reach a 65° angular displacement and exert a 87-μN force in the direction perpendicular to the substrate. We also discuss one potential application of controlling macroscopic fluidic mechanical systems using micromachined actuators. Results on using developed actuators to achieve rolling motion in a macroscaled delta-wing airfoil are presented.