Enhancing the post-buckling response of a composite panel structure utilising shape memory alloy actuators – a smart structural concept

Abstract

Restoration forces, associated with embedded activated pre-strained shape memory alloy wires, have successfully been employed to enhance the post-buckling behaviour of a laminated panel structure. An extensive experimental and numerical programme has been conducted, of which, results will be presented. The manufacturing methodology of the hybrid SMA/carbon/epoxy panel is outlined. The panel specimen features 0.3 mm diameter shape memory alloy wires embedded and partially consolidated to the host matrix at desired locations. Numerical thermal analysis has been employed to predict the non-uniform temperature profile, attributed to shape memory alloy activation through resistive heating, within the laminate. Structural finite element (FE) analysis has been employed to determine the hybrid panel's adaptive response while under the influence of the uniaxial compressive load in excess of its pseudo-critical buckling value. It is shown that, utilising the control authority generated from the small SMA actuator volume fraction employed, the out-of-plane displacement of the post-buckled laminated panel can be reduced. With the increase in use of composite materials within aerospace platforms, it is envisaged that the hybrid adaptive SMA/laminate configuration will extend the operational performance over conventional materials and structures, particularly when the structure is exposed to an elevated temperature.