Aerodynamic Control of Micro Air Vehicle Wings Using Electroactive Membranes

Electrically controlled adaptive materials are ideal candidates for developing high agility micro-air-vehicles (MAV) due to their intrinsic multi-functionality. The dielectric elastomer VHB 4910 is one such material, where deformation occurs with an applied electric field. Here, we study the aerostructural response and control authority of a VHB 4910 membrane wing. An experimental membrane-wing platform was constructed by stretching VHB 4910 over a rigid elliptical wing-frame. The low Reynolds number (chord Reynolds number < 10⁶) aerodynamics of the elliptical wing were characterized with different electrostatic fields applied. We observe an overall increase in lift with maximum gains of 20% at 4.5 kV, and demonstrate the ability to delay stall. Aerodynamic effects are investigated with membrane displacement and strain data obtained through visual image correlation (VIC). The VIC data is compared to a finite deforming finite element shell model to help understand structural shape changes under electrostatic fields and low Reynolds number aerodynamic flows. The model is formulated to directly input three dimensional membrane displacements to quantify aerodynamic loads on the electroactive membrane surface.