Design and manufacturing of highly tailorable pre-bent bi-stable composites

A composite bi-stable structure can deform and maintain its stable states without the need for constant energy inputs. In this paper we describe a class of composite bi-stable shells that makes use of ad-hoc stacking sequences and pre-bending to modify the curvature of the plate. These composite structures possess two types of bi-stability (same direction and opposite direction). The same-direction bi-stable structure is characterized by the presence of two stable states that face the same direction. The same-direction bi-stable configuration can produce a final shape of the shell that effectively minimises the overall volume of the structure and can therefore be used in reconfigurable and stowable antennas. We also describe a procedure to extend the duration of the transition process between the stable states from ~1 second to ~5 seconds. This slow transition
process can effectively reduce the potential damage to components attached to the bi-stable structure. The slow transition process described here is also relevant to further develop the technology readiness level of engineering applications involving multi-stable composites.