Shape-memory alloy actuation of insect-like flapping wings

Abstract
This paper presents the results from an exploratory investigation into the real-time shape adaptation of an artificial insect-like wing. Insect-like flapping flight offers many aerodynamic advantages at small scales, <150mm, compared to more conventional approaches to flight. However, it requires the implementation of low band-width high strain adaptation of aerofoil shape. The incorporation of Shape-Memory (SM) alloy actuators within composite wingforms offers one solution to such shape-changes. The results of this preliminary programme show that it is possible to introduce 'twist'and saddleshapes into insect-like wings using integrated SM actuators. This offers the potential for real-time adaptation of angle of attack during upstroke and structural stiffening during downstroke of a flapping wing. The paper also shows that these effects can be simply modelled by FE, analysis providing accurate data for SM actuator performance is available.