Four-Winged Flapping Flyer in Forward Flight

Abstract

We study experimentally a four-winged flapping flyer with chord-wise flexible wings in a self-propelled setup. For a given physical configuration of the flyer (i.e. fixed distance between the forewing and hindwing pairs and fixed wing flexibility), we explore the kinematic parameter space constituted by the flapping frequency and the forewing-hindwing phase lag. Cruising speed and consumed electric power measurements are performed for each point in the ( f , ϕ) parameter space and allow us to discuss the problem of performance and efficiency in four-winged flapping flight. We show that different phase-lags are needed for the system to be optimised for fastest flight or lowest energy consumption. A conjecture of the underlying mechanism is proposed in terms of the coupled dynamics of the forewinghindwing phase lag and the deformation kinematics of the flexible wings.

To tread or not to tread: comparison between water treading and conventional flapping wing kinematics

“…Several multidisciplinary research activities inspired by bird and insect flight have led to successful demonstrations of flapping wing vehicles. Some examples of roughly insect scales are the Delfly [1,2], Robobee [3,4], robotic hummingbird [5], TL-Flowerfly [6], fourwinged flappers [7] etc. Specifically, in the insect flight regime, flapping wings are driven by different mechanisms such as a system of gears and servo motors [1,8], torsional springs [9], electromagnetic actuators [10,11], or piezoelectric actuation [12].…”