| Popis: |
Morphing structures have long been desired in the various industries to enable, for example, efficient fluid flow in different flow regimes. However, problems with mechanical complexity, weight, and large energy requirements have meant that morphing structures have only been sparingly utilised. Current state of the art morphing technologies use systems of mechanical motors and hydraulics to create shape changes. These systems add parasitic weight, and are mechanically complex, adding to maintenance costs. Attempts have been made to use solid-state devices such as piezo-ceramics and shape memory alloys to create shape changes, however these devices rely on either extremely high voltages, or changes in atmospheric conditions in order to actuate. They also have comparatively poor mechanical properties. Here we present a concept of a solid-state electrochemically-actuated morphing structure manufactured from aerospace grade carbon fibre. The concept exploits expansions caused by lithium-ions intercalating into the carbon fibre microstructure. Both analytical and FE models are used to simulate a morphing three-layer laminate in a cantilever setup, and it is shown that relatively large deflections could be achieved, albeit at relatively low frequencies (in the range of mHz). An analysis of the likelihood of delamination occurring showed that there are no layups for which delamination is likely based on the estimated interlaminar strengths, and it is therefore unlikely that such a device would suffer from delamination in normal operational conditions. This concept paves the way for a new type of morphing structure that is mechanically simple, lightweight, and uses a low amount of energy to produce large shape changes without loss of mechanical integrity. QC 20200930 |
