Study of volumetric origami structure with highly anisotropic and tunable load carrying capacity

Abstract

Deployable structures have been of great interest for applications like space structures and portable architectures. However, these deployable structures often suffer from the lack of capabilities to support external load on their own. Thus, there is a high demand for a deployable yet rigid, load supporting structure. Here, I investigate analytically and experimentally the ability of an origami-based structure called the Tachi Miura Polyhedron (TMP), which can be used as deployable yet rigid structure. The TMP is a three dimensional origami structure representing bellows in appearance. It exhibits some unique mechanical properties, and here in particular, its force-displacement response is studied to establish its novel response mathematically. First, the force-displacement relations for the single TMP cell are developed in three mutually perpendicular directions of compression and are verified by experiments on paper prototypes. It is found that the single TMP exhibits a highly tunable load carrying ability under compression in one direction and tunable anisotropic behavior, i.e. variable load capacity depending on the loading directions and initial postures. This makes it a suitable choice for deployable yet rigid structures. Then the force displacement relations are extended to a multi-TMP structure in which multiple TMP cells are combined to form a cellular structure. It is found that the multi-TMP also exhibits tunable load capacity and tunable anisotropic behavior. Conclusively highly tunable and anisotropic load carrying mechanisms of the TMP are understood and established mathematically through this work, and the ability of this structure to be deployable yet load supporting is showcased by simple prototypes.