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 micromachin ing techniques in conjunction with electroplating of Permalloy (Ni80Fe20). Each actuator consists of a Permalloy piece attached to flexural cantilever beams, which are 400 mu m long and 100 mu m wide. Experiments show that un der a 6 X 10(4) A/m external magnetic field, an actuator with the volume of the magnetic piece being 1 mm X 1 mm X 5 mu m can reach a 65 degrees angul ar displacement and exert a 87-mu N force in the direction perpendicular to the substrate. We also discuss one potential application of controlling ma croscopic fluidic mechanical systems using micromachined actuators. Results on using developed actuators to achieve rolling motion in a macroscaled de lta-wing airfoil are presented. (C) 1999 Elsevier Science S.A. All rights r eserved.