Bistable morphing composite structures: A review

Bistable structures, a class of highly geometrically nonlinear morphing structures, have two stable configurations that remain in their respective equilibrium positions without the continuous application of an external force. This paper aims to summarise, review, and assess the literature about the theoretical studies, driving methods, numerical simulations, experimental investigations, and fields of application of the structures. The theoretical models are separated into anisotropic and isotropic composites based on the properties of the material. The generalised methods to study the bistability of structures with various properties are presented. The driving methods used to trigger the snap of one equilibrium structure to the other include mechanical force, piezoelectric actuation, shape memory alloy actuation, thermal actuation, and magnetic actuation. Numerical simulations of the curing process during manufacture and of the morphing process, which includes the snap-through and snap-back of the bistable structure, are reviewed. Moreover, the experimental investigations of structures with unsymmetric and antisymmetric layups are also presented. Bistable composite laminates and their structures have been used in aerospace, bionics, energy harvesting, and other fields due to their unusual behaviour and morphing potential. This paper also highlights the remaining challenges and possible future work on bistable composite transition, from phenomenon to potential applications.