Optimization of bistable composite laminates with actuated state-change

Adaptive structures offering large deformations with small and removable energy input are gaining increasing interest in the aerospace industry. One such mechanism is actuated asymmetric composite laminates. This paper presents an optimization formulation for the design of bistable laminates for reversible snap-through enabled by two orthogonal piezoelectric patches. The formulation optimizes the load carrying capability of the structure subject to deflection and actuation limits through variation in ply orientations and laminate geometry. We find the problem to be multimodal with the interactions between the optima and constraint boundaries to be dependent on the loading and snap-through directions and the values of the constraints. Reductions in total actuation voltage can be achieved through the simultaneous use of the positive and negative working ranges of two piezoelectric layers.