| Flying insects display remarkable maneuverability. Unlike typical airplanes, these insects are able to execute an evasive action, rapidly change their flight speed and direction, or leisurely land on flowers buffeted by wind, exhibiting aerodynamic feats unmatched by any state-of-the-art aircraft. By subtly tuning their wing motions, they generate and manipulate unsteady aerodynamic phenomenon that is the basis of their extraordinary maneuverability.;Inspired by these tiny animals, scientists and engineers have pushed the boundaries of technology in many aspects, including meso-scale fabrication, electronics, and artificial intelligence, to develop autonomous millimeter-scale flapping-wing robots. In this thesis, we demonstrate, on real insect-scale robots, that using only an approximate model of the aerodynamics and flight dynamics in combination with conventional tools in nonlinear control, the inherently unstable flapping-wing robot can achieve steady hover. We present the development of flight controllers that gradually enhance the flight precision, allowing the robot to realize increasingly aggressive trajectories, including a highly acrobatic maneuver---perching on a vertical surface, as observed in its natural counterparts. We also demonstrate that these experiments lead to higher fidelity of in-flight aerodynamic models, strengthening our understanding of the dynamics of the robot and real insects. |
