The strategic goal of this collaborative project is to establish a new, highly interdisciplinary research program in the field of adaptive structural systems. For obvious reasons engineering research need to be related to a specific application. In the frame of this proposal shape adaption is applied to an aircraft airfoil. Yet our findings will provide scientific fundament for many other applications.
The main challenge of a smart airfoil lays in the conflicting requirements of deformability and rigidity. In fact, no airplane could possibly fly with a compliant wing, due to the occurrence of dynamic (flutter) and quasi-static aeroelastic instabilities. Previous research on the smart airfoil was mostly based on a purely structural approach: mechanical engineers tried to solve this issue by optimizing the structural features of the wing (with compliant behavior only for selected deformation modes) which resulted in severe limitations for both the adaptability of the wing and its capability to sustain high speed aerodynamic loads.
Mechanical structures are designed to fulfill a range of design criteria, such as strength, stiffness, stability and fatigue requirements under specified loading conditions. Compliant structures are designed to be hinge-less, combining load-carrying properties with functionalities which are specific to mechanisms. Those functionalities are achieved by taking advantage of the elastic properties of the material thus introducing a controlled flexibility in the structure. Specific applications concern clamping or fixation mechanisms, energy storage and release, transfer or transform motion, force and energy and shape adaptation. The design of the next generations of products will take advantage of adaptive materials with their capabilities of controlled changes and adaptation in mechanical and physical properties. Adaptive structural systems will integrate actuators, sensors, energy conversion or dissipation elements that interact with the host structures by means of appropriate control devices. In this context adaptive structures open up new perspectives in terms of structural efficiency, multi-functionality and the capability to change shape and geometry in presence of time-varying environmental and operating conditions.