Tag Archives: flying

Publications Research

Four-winged flapping flyer in forward flight

mite4ailes Four-winged flapping flyer in forward flight
R. Godoy-Diana, P. Jain, M. Centeno, A. Weinreb & B. Thiria
In Klapp et al. (eds.), Selected Topics of Computational and Experimental Fluid Mechanics, Environmental Science and Engineering, pp. 147-158. Springer (2015).
[doi:10.1007/978-3-319-11487-3_8] PDF file

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. read more »

Research

Habilitation à diriger des recherches (HDR)

Bio-inspired swimming and flying – Vortex dynamics and fluid/structure interaction

Ramiro Godoy-Diana
Habilitation à diriger des recherches, Université Pierre et Marie Curie, 2014.
[hal.archives-ouvertes.fr]

PDF file here (19.4 MB)

The present document, prepared in view of obtaining the Habilitation à diriger des recherches, reviews my main research subject at PMMH since 2006, which concerns the study of swimming and flying inspired by nature. Canonical examples of flapping flight and undulatory swimming are explored using simplified experimental models as a starting point. This allows for the discussion of some fundamental questions related to the physics of bio-inspired locomotion at “intermediate” Reynolds numbers. In particular, we address the strong fluid-structure interactions that arise in these problems, where we have focused on: simplified models of flapping foils in hydrodynamic tunnel experiments, especially in the dynamics of vorticity in the wake of an oscillating foil ; mechanical models of flapping flyers with flexible wings in a self-propelled configuration (in the spirit of the pioneer experiments of Etienne-Jules Marey), as well as novel experimental models of undulatory swimming.
read more »

Publications Research

Force balance in the take-off of a pierid butterfly


montage_Pieris_rapae
Force balance in the take-off of a pierid butterfly: relative importance and timing of leg impulsion and aerodynamic forces

G. Bimbard, D. Kolomenskiy, O. Bouteleux, J. Casas & R. Godoy-Diana.
Journal of Experimental Biology, 216 : 3551-3563 (2013).

Abstract: Up to now, the take-off stage remains an elusive phase of insect flight relatively poorly explored compared to other maneuvers. An overall assessment of the different mechanisms involved in the force production during take-off has never been explored. Focusing on the first downstroke, we have addressed this problem from a force balance perspective in butterflies taking-off from the ground. read more »

Publications Research

Stabilizing effect of flexibility in the wake of a flapping foil

flex_vs_rig_jetStabilizing effect of flexibility in the wake of a flapping foil
C. Marais; B Thiria; Wesfreid, J. E. & R. Godoy-Diana.
Journal of Fluid Mechanics, 710 : 659-669 (2012).

Abstract: The wake of a flexible foil undergoing pitching oscillations in a low-speed hydrodynamic tunnel is used to examine the effect of chordwise foil flexibility in the dynamical features of flapping-based propulsion. read more »

Publications Research

Behind the performance of flapping wing flyers

flapping_wingRather than resonance, flapping wing flyers may play on aerodynamics to improve performance
S. Ramananarivo; R. Godoy-Diana & B. Thiria.
Proceedings of the National Academy of Sciences (USA), 108 (15): 5964-5969 (2011).

Abstract: Saving energy and enhancing performance are secular preoccupations shared by both nature and human beings. In animal locomotion, flapping flyers or swimmers rely on the flexibility of their wings or body to passively increase their efficiency using an appropriate cycle of storing and releasing elastic energy. Despite the convergence of many observations pointing out this feature, the underlying mechanisms explaining how the elastic nature of the wings is related to propulsive efficiency remain unclear. Here we use an experiment with a self-propelled simplified insect model allowing to show how wing compliance governs the performance of flapping flyers. read more »

Publications Research Video

Bending to fly

How wing compliance drives the efficiency of self-propelled flapping flyers
B. Thiria & R. Godoy-Diana.
Physical Review E, 82 : 015303(R) (2010).
*arXiv preprint blogged in MIT Technology Review (March 2, 2010)
*Also referenced in Vir. J. Bio. Phys. Res. / Volume 20 / Issue 3 / (August 1, 2010)

 

Abstract: Wing flexibility governs the flying performance of flapping-wing flyers. Here, we use a self-propelled flapping-wing model mounted on a ”merry go roun” to investigate the effect of wing compliance on the propulsive efficiency of the system. read more »