A Study of Bistable Laminates of Generic Lay-Up for Adaptive Structures



Abstract:  Asymmetric laminates are known to exhibit two stable cylindrical states and one unstable saddle state. Such bistability has attracted attention in aerospace applications because of the potential low energy requirement to achieve a large deflection or change in shape. This paper presents experimental observations of a generic asymmetric [−30/60] laminate with and without piezoelectric actuation and compares against both energy-based analytical and finite element (FE) models. It is observed that the analytical model offers a qualitative understanding of bistable behaviour, degree of curvature and overall shape but is unable to model the distinctive curvature changes near the boundaries which can be captured by the FE model. The investigation also presents the use of piezoelectric actuation to achieve snap-through in both analytical and FE models, which is compared and validated with experimental characterisation.