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Passive wing pitch reversal in insect flight

Published online by Cambridge University Press:  30 October 2007

ATTILA J. BERGOU
Affiliation:
Department of Physics, Cornell University, Ithaca, NY 14853, USA
SHENG XU*
Affiliation:
Department of Theoretical and Applied Mechanics, Cornell University, Ithaca, NY 14853USA
Z. JANE WANG
Affiliation:
Department of Theoretical and Applied Mechanics, Cornell University, Ithaca, NY 14853USA
*
Present address: Department of Mathematics, Southern Methodist University, Dallas, TX 75275, USA.

Abstract

Wing pitch reversal, the rapid change of angle of attack near stroke transition, represents a difference between hovering with flapping wings and with a continuously rotating blade (e.g. helicopter flight). Although insects have the musculature to control the wing pitch during flight, we show here that aerodynamic and wing inertia forces are sufficient to pitch the wing without the aid of the muscles. We study the passive nature of wing pitching in several observed wing kinematics, including the wing motion of a tethered dragonfly, Libellula pulchella, hovering fruitfly, hovering hawkmoth and simplified dragonfly hovering kinematics. To determine whether the pitching is passive, we calculate rotational power about the torsion axis owing to aerodynamic and wing inertial forces. This is done using both direct numerical simulations and quasi-steady fluid force models. We find that, in all the cases studied here, the net rotational power is negative, signifying that the fluid force assists rather than resists the wing pitching. To further understand the generality of these results, we use the quasi-steady force model to analyse the effect of the components of the fluid forces at pitch reversal, and predict the conditions under which the wing pitch reversal is passive. These results suggest the pitching motion of the wings can be passive in insect flight.

Type
Papers
Copyright
Copyright © Cambridge University Press 2007

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References

REFERENCES

Andersen, A., Pesavento, U. & Wang, Z. J. 2005 a Analysis of transitions between fluttering, tumbling and steady descent of falling cards. J. Fluid Mech. 541, 91104.CrossRefGoogle Scholar
Andersen, A., Pesavento, U. & Wang, Z. J. 2005 b Unsteady aerodynamics of fluttering and tumbling plates. J. Fluid Mech. 541, 6590.CrossRefGoogle Scholar
Combes, S. A. & Daniel, T. L. 2003 Flexural stiffness in insect wings ii. Spatial distribution and dynamic wing bending. J. Exp. Biol. 206, 29892997.CrossRefGoogle ScholarPubMed
Dickinson, M. H., Lehmann, F.-O. & Götz, K. G. 1993 The active control of wing rotation by drosophila. J. Exp. Biol. 182, 173189.CrossRefGoogle ScholarPubMed
Ellington, C. P. 1984 The aerodynamics of hovering insect flight. i. The quasi-steady analysis. Phil. Trans. R. Soc. Lond. B 305 (1122), 115.Google Scholar
Ennos, A. R. 1988 The inertial cause of wing rotation in diptera. J. Exp. Biol. 140, 161169.CrossRefGoogle Scholar
Fry, S. N., Sayaman, R. & Dickinson, M. H. 2005 The aerodynamics of hovering flight in drosophila. J. Exp. Biol. 208, 23032318.CrossRefGoogle ScholarPubMed
Norberg, R. 1972 The pterostigma of insect wings an inertial regulator of wing pitch. J. Comput. Physiol. 81, 922.CrossRefGoogle Scholar
Pesavento, U. & Wang, Z. J. 2004 Falling paper: Navier–Stokes solutions, model of fluid forces, and center of mass elevation. Phys. Rev. Lett. 93 (14), 144501-1144501-4.CrossRefGoogle ScholarPubMed
Russell, D. B. 2004 Numerical and experimental investigations into the aerodynamics of dragonfly flight. PhD thesis, Cornell University.Google Scholar
Sane, S. P. & Dickinson, M. H. 2002 The aerodynamic effects of wing rotation and revised quasi-steady model of flapping flight. J. Exp. Biol. 205, 10871096.CrossRefGoogle ScholarPubMed
Sedov, L. I. 1965 Two-Dimensional Problems in Hydrodynamics and Aerodynamics. Interscience.CrossRefGoogle Scholar
Song, D., Wang, H., Zeng, L. & Yin, C. 2000 Measuring the camber deformation of a dragonfly wing using projected comb fringe. Rev. Sci. Instrum. 72, 24502454.CrossRefGoogle Scholar
Wang, Z. J. 2000 Two dimensional mechanism for insect hovering. Phys. Rev. Lett. 85, 22162219.CrossRefGoogle Scholar
Wang, Z. J., Birch, J. M. & Dickinson, M. H. 2004 Unsteady forces and flows in low Reynolds number hovering flight: two-dimensional computations vs. robotic wing experiments. J. Exp. Biol. 207, 449460.CrossRefGoogle ScholarPubMed
Wang, Z. J. & Russell, D. 2007 The effect of fore and hind-wing interactions on aerodynamic force and power in dragonfly flight. Phys. Rev. Lett. (in press).CrossRefGoogle Scholar
Weis-Fogh, T. 1973 Quick estimates of flight fitness in hovering animals, including novel mechanisms for lift production. J. Exp. Biol. 59, 169230.CrossRefGoogle Scholar
Willmott, A. P. & Ellington, C. P. 1997 a The mechanics of flight in the hawkmoth manduca sexta i. Kinematics of hovering and forward flight. J. Exp. Biol. 200, 27052722.CrossRefGoogle ScholarPubMed
Willmott, A. P. & Ellington, C. P. 1997 b The mechanics of flight in the hawkmoth manduca sexta ii. Aerodynamic consequences of kinematic and morphological variation. J. Exp. Biol. 200, 22732745.Google ScholarPubMed
Xu, S. & Wang, Z. J. 2006 a An immersed interface method for simulating the interaction of fluid with moving boundaries. J. Comput. Phys. 216, 454493.CrossRefGoogle Scholar
Xu, S. & Wang, Z. J. 2006 b Systematic derivation of jump conditions for the immersed interface method in three-dimensional flow simulation. SIAM J. Sci. Comput. 27, 19481980.CrossRefGoogle Scholar