Dynamics and Control of a Biomimetic Vehicle Using Biased Wingbeat Forcing Functions: Part II - Controller

Abstract

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. Using the derivation of the aerodynamic forces and moments from Part I, a control allocation strategy and a feedback control law are designed that enable the vehicle to achieve untethered, stabilized flight about a hover condition. Six degree-of-freedom maneuvers near hover are demonstrated as well. The control laws are designed to make use of two actuators that control the angular position of the wing in the stroke plane. The SplitCycle Constant-Period Frequency Modulation with Wing Bias technique, introduced in Part I, is used to allow each wing to generate non-zero cycleaveraged aerodynamic forces and moments. This technique modifies the frequencies of the up and down strokes to yield non-zero cycle-averaged drag due to the flapping motion of a wing. Additionally, the midpoint of the wingbeat profile can be modified by use of a wing bias. The bias is introduced to primarily provide pitching moment control. In this work, the sensitivities of cycle-averaged forces and moments with respect to the