Folding and Deployment of Thin Shell Structures

Abstract

Thin shells made of high modulus material are widely used as lightweight deployable space structures. The focus of this chapter is the most basic deployable thin shell structure, namely a straight, transversely curved strip known as a tape spring. Following a review of the materials used for the construction of deployable thin shell structures, including constitutive models and failure criteria developed specifically for this type of structures, this chapter provides an introduction to the mechanics of tape springs and tape spring hinges. Finite element techniques to model deployable structures containing tape springs are presented and the ability of these models to accurately simulate experimentally observed behavior is demonstrated. These tools can be used to design structures able to achieve specific behaviors. As an example, the design of a two-hinge boom that can be wrapped around a small spacecraft without any damage, and can dynamically deploy and smoothly latch into the deployed configuration is presented.