Unobtrusively Actuated Origami Structures

Abstract

The kinematics of Miura-fold origami enables the creation of expandable structures with uniquely high packing ratios. This project’s focus was to develop an actuation method for these structures that avoided hinge interference to maintain the highest packing ratio. By using cheap, unobtrusive pneumatic cylinders that fit within material thickness, this goal could be met. As the project evolved, an analytical model was developed to determine the size and number of actuators necessary for a generic structure, better hinging and assembly designs were developed, and groundwork was laid for determining structure panel strength. To demonstrate these developments, a polypropylene structure was designed that features a square top-down cross-section, weighs approximately 45lbs, can expand from 14” to 45” tall, utilizes 0.02” living hinges with rounded profiles for folding, demonstrates full structure actuation by pneumatic cylinders, and shows that the analytical model gauged actuation energy and maximum force within a 6% accuracy range.