A mechanism for testing the torsional mechanics of origami-inspired hinges

Abstract

Folding 2-dimensional sheets into static and dynamic 3-dimensional structures has the potential to improve rate, cost, and flexibility in manufacturing. In order to explore origami-inspired design, a better understanding of the mechanics of the fold is needed. This is to create better mathematical models and design for particular stiffness and fatigue specifications. The purpose of this study is to create a desktop machine that enables the measurement of the torsional stiffness of folded hinges over a wide angular range and a large number of cycles. This machine was then used to test 100 and 140 lb papers with 4 and 14 scores for the crease. Each paper was tested for 10 cycles and stiffness calculated. It was shown that 40 lb papers have higher reaction forces than the 100 lb papers. Stiffness measurements were inconclusive due to possible bending in addition to the hinging. For the 200 cycle around a 2 g decrease can be seen from I cycle to 200 cycles.