Design and analysis of a grid patch multi-stable composite

Abstract

In this paper, the effect of stacking sequences on the number of stable configurations for multi-patch composite panel is studied. The model is designed by connecting a number of bi-stable composite patches in a grid. The total strain energy equation with a fourth order shape function including variations of the curvatures is applied in conjunction with a Rayleigh-Ritz technique for fast predication of stable shapes. A square panel model consisting of four connected patches of asymmetrical laminate is designed with 0° and 90° ply's angle, and then the model is extended by a mix of symmetric and asymmetric laminates. The stable shapes of model are validated using both FE predictions and experimental tests, and the results show quite good agreements in the stable configurations. Each case of panels exhibits two or more distinct stable configurations, which are mainly dependent on distribution of stacking sequences on surface. These stable configurations are interesting shapes that may be used to create a large multi-stable surface as useful device in a morphing skin application. This work could be used as a guideline for design of a large multi-patch morphing skin for highly degree of stability.