Active Hybrid Composite Actuators – A Comparison of Different Design Approaches

Abstract:
Combining the outstanding actuation capability of shape memory alloys (SMA) with fiber reinforced polymers (FRP) on the materials level leads to an active hybrid composite material, which provides new opportunities for shape changing structures. Properties can be tailored to specific application needs, which especially for aerodynamic systems allows for thin and lightweight structures with the ability to change surface curvature smoothly and without gaps or kinks on demand. Being one of the first applications of such active hybrid structures made from SMA-wires and a hosting FRP structure, we demonstrate the potential of this new technology with a fully integrated system of active vortex generators for a glider, using an integral design of the active elements. This contribution presents the design process for the whole system together with experimental results from tests in laboratory as well as under real world conditions in a flight test. Two distinct descriptions of the actuator system will be described, focusing on static and dynamic actuation performance, energy requirements under different aerodynamic and thermal loading as well as ease of manufacturing and integration aspects.