Deployable and Mechanical Properties of An Origami Spring Structure*

Origami has recently been studied intensively by physicists, mathematicians, and engineers due to its deployability, versatility and low cost in potential engineering applications. Examples include self-deployable solar arrays in space and self-folded origami inspired robots. To understand deployable properties of an origami structure, models of an origami “spring” were investigated. Origami spring structures may be useful in robotics and structural designs as their length can vary, while maintaining structural rigidity. Mathematical methods based on the geometry of these spring structures are used to predict ideal maximum height, formulate a relationship between the angle of rotation and the spring height, and to obtain a Poisson’s ratio of the spring structure. We show that the Poisson’s ratio is not constant and is scalable with respect to different geometric parameters. Elastic modulus of the spring structures are also predicted using models based on Hooke’s law and the stationary principle. By studying origami spring models, we discovered interesting and potentially practical engineering designing insights that are embedded in this smart structure.