Closed cross-section dual-matrix composite hinge for deployable structures

Dual-matrix composite structures with localized elastomer composite hinges have been proposed to enable packaging with much smaller fold radii than allowed by traditional resin-based fiber reinforced composites. Previous studies have been limited to proof-of-concept of folding capabilities and constitutive modeling of elastomer composites. A novel closed cross-section dual-matrix deployable hinge is studied here to develop the tools for studying the deployment of general dual-matrix structures. A set of tools for the analysis of deployment of this simple structure is developed: an analytic model that minimizes the strain energy in the folded configuration, experimental characterization, and finite element techniques using the LS-Dyna commercial software. The three models are used to predict the packaged shape and deployment moments, and are shown to be in good agreement amongst themselves. The analytic model is used to demonstrate control of the folded shape of the hinge using the stiffness of the elastomer composite. This behavior is verified using finite element models developed in the LS-Dyna commercial code. The simulations are used to predict the localized fold radius of the hinge within 3% and deployment moments within 5% by accounting for the microbuckled stiffness of the elastomer composite.