Effect of hinge elasticity on morphing winglet mechanical systems

After pioneering examples in the '70 and the '80, technology advances have brought aircraft morphing systems close to the exploitation on commercial vehicles. However, in spite of many successes, further steps shall be accomplished before series production lines are entered. They introduce new needs and sometimes exasperate aspects till now under control in the design phase. The increased number and kind of parts pushes for implementing additive manufacturing techniques; their modelling gives rise in turn to important simulation challenges. In case of mechanical, alternative to compliant systems, modelling of elements shall take in consideration behavior that is substantially different from the analogous counterparts on classical devices. Hinges and torsion bars are more diffused and smaller in these architectures. This work deals with hinges modelling inside mechanically-driven architectures for adaptive winglets. Impact of these aerodynamic surfaces on aircraft stability is crucial and accurate models are required to guarantee their correct implementation. Morphing capability emphasizes this occurrence even more. Schematization effects are investigated in terms of both static and dynamic response. The variation of the deformed shape is therefore examined, identifying the strain map and internal forces distribution changes, essential for design purposes and stress analysis. Modal characteristics deviations are then explored, which may substantially influence aeroelastic stability margins. It is envisaged that this approach could be exploited to consider lags effect. A parametric investigation is finally carried out to identify structural behavior sensitivity to such kind of modifications.