Flying insects are able to navigate complex and highly dynamic environments, can rapidly change their flight speeds and directions, are robust to environmental disturbances, and are capable of long migratory flights. However, flying robots at similar scales have not yet demonstrated these characteristics autonomously. Recent advances in mesoscale manufacturing, novel actuation, control, and cus...

This paper analyzes the lift-production system in hovering of flapping wing robot COLIBRI size a hummingbird. The first examines mechanism for which new gear transmission is proposed to reduce friction and facilitate assembly. Next, sensitivity analysis performed on size. Then, discusses several options gearbox, various DC motors two battery configurations (a single or batteries series) minimiz...

Neuroanatomical evidence argues for the presence of taste sensilla in Drosophila wings; however, the taste physiology of insect wings remains hypothetical, and a comprehensive link to mechanical functions, such as flight, wing flapping, and grooming, is lacking. Our data show that the sensilla of the Drosophila anterior wing margin respond to both sweet and bitter molecules through an increase ...

The development of flapping-wing micro air vehicles (MAVs) demands a systematic exploration of the available design space to identify ways in which the unsteady mechanisms governing flapping-wing flight can best be utilized for producing optimal thrust or maneuverability. Mimicking the wing kinematics of biological flight requires examining the potential effects of wing morphology on flight per...

Using a dynamically scaled robotic wing, we studied the aerodynamic torque generation of flapping wings during roll, pitch, and yaw rotations of the stroke plane. The total torque generated by a wing pair with symmetrical motions was previously known as flapping counter-torques (FCTs). For all three types of rotation, stroke-averaged FCTs act opposite to the directions of rotation and are colli...

A numerical framework is presented to simulate rigid and flexible flapping wings. The fluid-structure interaction is realized by coupling a Navier-Stokes solver to a geometrically nonlinear co-rotational structural solver. In the coupled fluid-structure interaction interface the aerodynamic loading and deformed wing surface are shared by two solvers within each time step. A remeshing method bas...

The aerodynamic performance of hovering insects is largely explained by the presence of a stably attached leading edge vortex (LEV) on top of their wings. Although LEVs have been visualized on real, physically modeled, and simulated insects, the physical mechanisms responsible for their stability are poorly understood. To gain fundamental insight into LEV stability on flapping fly wings we expr...

We study the dynamics of a rigid, symmetric wing that is flapped vertically in a fluid. The motion of the wing in the horizontal direction is not constrained. Above a critical flapping frequency, forward flight arises as the wing accelerates to a terminal state of constant speed. We describe a number of measurements which supplement our previous work. These include a a study of the initial tran...

All natural flyers equip flexible wings. It’s widely thought that the wing flexibility can play important roles in flight aerodynamics. In the current work, a combined experimental and computational method is developed to study the role of morphing wing in hovering dragonfly aerodynamic performance. We start with taking high-speed images of a freely flying dragonfly. Next, a surface reconstruct...

Wing or fin flexibility can dramatically a↵ect the performance of flying and swimming animals. Both laboratory experiments and numerical simulations have been used to study these e↵ects, but analytical results are notably lacking. Here, we develop small-amplitude theory to model a flapping wing that pitches passively due to a combination of wing compliance, inertia, and fluid forces. Remarkably...