Shield Design for Shape-Shifting Surfaces

Shape-Shifting Surfaces (SSSs) are multilayered surfaces that are able to change shape while maintaining their integrity as physical barriers. SSSs are composed of polygonal unit cells, which can change side lengths and corner angles. These changes are made possible by each side and corner consisting of at least two different shields, or layers of material. As the layers undergo relative motion, the unit cell changes shape. In order for the SSS to retain its effectiveness as a barrier, no gaps can open between different layers. Also, the layers cannot protrude past the boundaries of the unit cell. Based on these requirements, a design space exploration was performed to determine, using equilateral triangle unit cells and triangular shields, the maximum deformation range of a unit cell. It was found that the triangular shields with maximum allowable deformation were right triangles with one of the angles being equal to 37.25 degrees and the adjacent side equal to 61% of the side length of the unit cell. The key contribution of this paper is a first algorithm for systematic SSS shield design. Possible applications for SSSs include protection, by creating body-armor systems; reconfigurable antennas able to broadcast through different frequencies; recreational uses, and biomedical applications.