Morphing Wing

But flight stability with morphing wings is possible—consider the peregrine falcon. Swifts are another kind of acrobat flier. Researchers... 

Lentink, D U. K. Muller, E. J. Stamhuis, R. de Kat, W. van Gestel, L. L. M. Veldhuis, et al. How Swifts Control Their Glide Performance with Morphing Wings. Nature 446 (April 26, 2007) 1,082-1,085. The researchers conducted wind tunnel experiments demonstrating that by changing the shape of their wings, swifts can fly up to 60 percent farther and turn up to three times faster. 

Fig. 3 Examples for application fields of SMPs. (A) Offset fed antenna reflector in packaged shape (B) dress with adaptable fashion made of SMP fibers (taken from [17] by permission of Woodhead Publishing LTD, UK) (C) reusable mandrel for tooling (taken from [6], reprinted by permission from the Society for the Advancement of Material and Process Engineering (SAMPE)) deployable antenna reflector of satellite in open (D) and closed (E) shape (F) aircraft with morphing wings (G) spoons for handicapped people (taken from [183] by permission of lOP) (H) intravenous cannula from SMP (taken from [183] by permission of lOP) (J) hinge made of an SMP composite. A, D, E, F, J provided by CTD Composite Technology Development...

Fig. 2.6. Morphious , the Virginia Tech morphing wing wind tunnel simulator a cruise configuration, b attack configuration, c wing twist (Photos courtesy of the designer David A. Neal, III)...

Bae, J.S. Siegler, T.M. Inman, D.J. Aerodynamic and Static Aeroelastic Characteristics of a Variable-Span Morphing Wing. AIAA J. Aircraft, Vol. 42, No. 2. 

Defense Advanced Research Projects Agency (DARPA) begins a project, Morphing Aircraft Structures, to investigate the potential of such technology as shape-changing wings. 

Howard, R. W. and Liang, Y. (1993). Cuticular hydrocarbons of winged and wingless morphs of the ectoparasitoid Choetospila elegans Westwood (Hymenoptera Pteromalidae) and its host, larval lesser grain borer (Rhyzopertha dominica) (Coleoptera Bostrichidae). Comp. Biochem. Physiol. B, 106,407 414. 

The techniques devised at the University of Horida directly address the issue of wind gusts. When the local airspeed over the wing changes suddenly, the increased pressure causes the membrane to deform and lose camber. As a result, the Cl decreases, but the increase in velocity yields a nearly constant value of lift. This type of passive morphing is referred to as load spilling. 

Garcia H, Abdulrahim M, Lind R (2003) Roll control micro air vehicle using active wing morphing. AIAA paper 2003-5347, AIAA guidance, navigation control conference, Austin, TX, 11-14 Aug 2003... 

Honig, L. S. and Summerbell, D. (1985) Maps of strength of positional signalling activity in the developing chick wing. J. Embryol. Exp. Morph. 87,163-174. Hombruch, A. and Wolpert, L.(1991) The spatial and temporal distribution of polarizing activity in the flank of the pre-limb-bud stages in the chick embryo. Development 111, 725-731. 

Smith, J. C. (1980) The time required for positional signalling in the chick wing bud. J. Embryol. Exp. Morph. 60, 321-328. 

Scherer, L.B. Martin, C.A. Sanders, B. West, M. Florance, J. Wieseman, C. Burner, A. and Fleming, G. DARPA/AFRL Smart Wing Phase 2 Wind Tunnel Test Results. SPIE Vol. 4698 (2002), pp. 64-75 Cabell, R.H. Schiller, N. Mabe, J.H. Ruggeri, R.T. Butler, G.W. Feedback Control of a Morphing Chevron for Takeoff and Cruise Noise Reduction. Proc. ACTIVE 04 Williamsburg/VA, USA (2004)... 

C.E.S. Cesnik, Wing shape deformation for high-performance aerial vehicles. ICASE Morphing Seminar Series. Presentation (2002)... 

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