23rd Congress of International Council of the Aeronautical Sciences, 8-13 September, 2002, Toronto, Canada
Paper ICAS 2002-5.5.1 (I.L.)

FLIGHT DYNAMICS OF SMALL VEHICLES

S. Ho (1), H. Nassef (1), N. Pornsin-Sirirak (2), Y-C. Tai (2), C-M. Ho (1)
(1) University of California, USA; (2) California Institute of Technology, USA

Keywords: unsteady aerodynamics, micro air vehicles, active flow control, mems

Experimental studies of both the unsteady aerodynamics of micro air vehicles [MAVs] utilizing flapping wings and various active flow control strategies for flexible aerodynamic surfaces are described. Flow visualization and lift and thrust measurements clearly show that a stable unsteady leading edge vortex and its interaction with the stiffness distribution of a flapping wing determine the aerodynamic performance of the MAV. Two active flow control strategies, one for local vortex control using electrostatically controlled checkvalve actuators fabricated directly on the wing, and the other involving instantaneous variation of the wing’s angular speed to achieve global vortex control, are also presented. Combined with a novel distributed control algorithm (the Gur Game), they light a path toward adaptive flow control of flexible surfaces.

view full paper