Changing the aerodynamic forces acting on an aerofoil is most commonly done by camber change using an actuated pin-jointed control surface at the trailing edge. There can be significant mass penalties with such devices and achieving a smooth camber variation is difficult. This work presents a design for an aerofoil section which has at least two stable camber geometries. The aerofoil’s multistability derives from the use of a novel tape-spring assembly. A tape-spring is effectively a cylindrical shell. They possess the unusual mechanical property of being able to be folded elastically and lock when straightened. The design case considered is based on a typical helicopter main rotor blade. The multistable device is used to improve the performance of the rotor blade during the transition between hover and forward flight. Force-displacement characteristics of the flap are found experimentally and compared with finite element and analytical models. Both modelling techniques are in good agreement with the manufactured demonstrator.
|Translated title of the contribution||Multistable Tape-Spring Assemblies for Morphing Aerofoil Applications|
|Title of host publication||19th International Conference on Adaptive Structures and Technologies (ICAST), Ascona, Switzerland|
|Pages||1 - 9|
|Number of pages||9|
|Publication status||Published - 6 Oct 2008|