Topology Optimization of Origami Structures based on Crease Pattern and Axial Rigidity

Origami structures exhibit desirable stowage properties for application in deployable space structures. This work presents a description of the kinematics and proposes a design method using topology optimization. In order to expand the design envelope, using a truss model, the objective is to find the optimal configuration of the trusses based on axial rigidity and the crease pattern that maximizes the displacement at set locations, under prescribed forces and boundary conditions. First, a linear method is used to determine small strain and small rotation mechanics of flexible origami, with the aim of studying the behavior at the initiation of folding. Subsequently, a nonlinear method is implemented to consider large displacement and large rotation mechanics. To carry out the optimization process, constraints on the number of active fold lines and on the axial rigidity distribution are applied. Previous studies on topology optimization of origami structures have considered only folding and bending in their analyses. Here, it is shown that including the axial rigidity as a design variable leads to new promising origami designs.