Morphing structures suitable for unmanned aerial vehicles (UAVs) have been investigated\nfor several years. This paper presents a novel lightweight, morphing concept based on the exploitation\nof the â??lever effectâ? of a bistable composite plate that can be integrated in an UAV horizontal tail.\nFlight dynamics equations are solved in Simulink environment, thus being able to simulate and\ncompare different flight conditions with conventional and bistable command surfaces. Subsequently,\nbistable plates are built by using composite materials, paying particular attention to dimensions,\nasymmetric stacking sequence and total thickness needed to achieve bistability. NACA0011 airfoil is\nchosen for proving this concept. Wind tunnel tests demonstrate that the discrete surface is capable of\nwithstanding the aerodynamic pressure. A remotely piloted vehicle is employed to test the discrete\nhorizontal tail command during the take-off. The results show that, choosing a proper configuration\nof constraints, stacking sequence and aspect ratio for the bistable laminate, it is possible to tailor\nthe snap-through mechanism. The proposed concept appears lighter and increases aerodynamic\nefficiency when compared to conventional UAV command surfaces.
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