Dynamics and Control of a Minimally Actuated Biomimetic Vehicle: Part II - Control

A control strategy is proposed for a minimally-actuated flapping-wing micro air-vehicle (FWMAV). The proposed vehicle is similar to the Harvard RoboFly that accomplished the first takeoff of an insect scale flapping wing aircraft, except that it is equipped with independently actuated wings and the vehicle center-of-gravity can be manipulated for control purposes. Using the results from the derivation of the aerodynamic forces and moments from Part I, a control allocation strategy and a feedback control law are designed that enables the vehicle to achieve untethered, stabilized flight about a hover condition. The control laws are designed to make use of three actuators, two of which control the angular position of the wing in the stroke plane, and one that moves a bob-weight that manipulates the vehicle center-of-gravity. The Split-Cycle Constant-Period Frequency Modulation technique, introduced in Part I, is used to allow each wing to generate nonzero cycle-averaged rolling and yawing moments. The technique achieves this objective by varying the frequency of the oscillators, that drive each wing throughout the wing-beat cycles, such that the dynamic pressure acting on each wing during the upstroke is different from that which acts on the