Design, Analysis and Prototype Testing of a Non-explosive Self-deploying Wing Actuated by NiTi Shape Memory Alloy Wires

Abstract This paper introduces an innovative approach to the deployment of folding wings on cruise missiles, aiming to overcome the issues associated with explosive devices. The proposed solution involves employing NiTi shape memory wires for a nonexplosive self-deploying wing mechanism. The fundamental concept of the design revolves around the utilization of NiTi wires, which contract upon electric heating. This contraction action severs the shear pin, consequently releasing the folded wings. The operational performance of the NiTi wire is thoroughly examined through a series of electro-thermo-mechanical tests, offering valuable insights for selecting the appropriate wire material. Moreover, the mechanical dynamics involved in the self-deploying process are elucidated through finite element simulations. The simulations highlight that the thermally-induced phase transformation within the NiTi wires generates substantial actuation forces, exceeding 700 N, and strokes of over 6 mm. These forces are deemed sufficient for breaking the aluminum shear pin and effecting wing deployment. The proposed mechanism’s practical viability is substantiated through prototype tests, which conclusively establish the superiority of the nonexplosive self-deploying wing mechanism when compared to conventional methods. The experimental outcomes underscore the mechanism's capability to markedly reduce overload stress while remaining compliant with the designated requirements and constraints.