Study on Mechanical Behavior of Bi-Stable Laminated Ultra-thin Shells with Piezoelectric Layers

The deployable laminated composite shells are straight thin-walled tubes with a partial or full circular cross-section. They are configurable between two stable states of the structure: a coiled state in which the structure is folded along its length and an extended state in which the structure is unfolded. These ultra-thin flexible shells are folded without large permanent deformation and are capable of self-deployment through the controlled release of elastic strain energy accumulated during folding. The expected uses in industry have been intensifying the need for a comprehensive understanding of their prominent bi-stable behaviours.This project aims to establish an analytical model for the shells with piezoelectric layers placed on the surfaces, and to derive an explicit formula for elastic strain energy incorporating the effect of bending-stretching coupling used to control a characteristic parameter, i.e., rolled-up radii of the structures. Meanwhile, a numerical approach will be developed to validate the theoretical model.