Suppression of cross-well vibrations of a bistable square cross-ply laminate using an additional composite strip

The behavior of bistable structures having two local potential energy minima has been extensively explored in recent years. In bistable systems, both stable states are located at their potential energy wells, where the shape transition can be triggered by overcoming the energy barrier between them. Nature of the potential energy landscape plays a vital role in the snap-through behavior of such structures. For regular geometries like a perfect square-shaped bistable plate, minima of the potential energy landscape is perfectly symmetric and complementary to each other. Potential energy landscape with perfectly symmetric local minima may lead to continuous cross-well vibrations as the snap-through, and reversible snap-through requirements are identical. Such vibrations are often undesirable for morphing applications where stationary control of the structural configurations is required. In continuation to the previously reported novel strategy to generate a tunable potential energy landscape in a square bistable cross-ply laminate by attaching an additional composite strip, the present study reveals the dynamic design space of strip attached to square bistable cross-ply laminate. A Rayleigh–Ritz-based semi-analytical formulation and a fully nonlinear finite element model are employed to investigate the dynamic characteristics of unsymmetrical laminate with an additional composite strip. A parametric study is performed to explore the changes in the potential energy landscape and corresponding dynamic characteristics with changes in the width and thickness of the strip. In order to suppress undesirable cross-well vibrations from a periodic excitation, optimum design parameters of the strip (width and thickness) are reported in the study.