A shape memory-based multifunctional structural actuator panel

A multifunctional panel concept is presented in which a lightweight, structurally efficient sandwich panel is able to undergo a reversible change in shape upon application of a localized thermal stimulus while supporting significant load. The shape change is effected by shape memory alloy face sheet elements. which exploit a "one-way" shape memory effect only. Unlike other related designs, no external or bias forces are required to complete the full cycle of shape change. The reversible shape change is accomplished by a core design which forces an inactive face sheet to martensitically deform in tension when the opposing face sheet undergoes a length change. By alternately heating one face sheet and then the other, the sandwich panel is able to perform fully reversible cyclic shape changes. The performance of the sandwich panel, in terms of required thermal power, actuation frequency, peak load hearing capacity. stiffness. and weight, can be optimized by proper selection of face sheet material and its thickness. the overall core thickness, core member thickness and length, and the design of the joint connecting core members and face sheet. (C) 2004 Elsevier Ltd. All rights reserved.