A nonlinear iterative approach to predict large deflections of a novel spring-loaded ornithopter wing

In this study, a new design of an ornithopter wing has been introduced whose stiffness can be controlled and varied according to design requirements using a spring introduced at the trailing edge. The new patented wing design consists of a leading edge spar, supported by an arrangement of ribs. One or more springs can be attached to the trailing edge which keeps the wing taut and maintains the span-wise twist of the wing when a load is applied. A numerical iterative approach has been developed to calculate the large deformations of the wing when a known load distribution is applied to this wing. Notably, this method overcomes the limitations of conventional Finite Element Methods, accounting for multiple ribs and spring configurations. Experimental validation confirms the accuracy of the proposed approach, offering a significant advancement in modelling complex ornithopter wing deformations and paving the way for improved design optimisation.