Heat set creases in polyethylene terephthalate (PET) sheets to enable origami-based applications

Abstract

Polyethylene terephthalate (PET) sheets show promise for application in origami-based engineering design. Origami-based engineering provides advantages that are not readily available in traditional engineering design methods. Several processing methods were examined to identify trends and determine the effect of processing of PET sheets on the crease properties of origami mechanisms in PET. Various annealing times, temperatures, and cooling rates were evaluated and data collected for over 1000 samples. It was determined that annealing temperature plays the largest role in crease response. An increase in the crystallinity of a PET sheet while in the folded state likely increases the force response of the crease in PET sheets. An annealing time of at least 60 min at 160 °C-180 °C with a quick cooling results in a high force response in the crease. The effectiveness of the processing methods was demonstrated in several origami patterns of various complexities.

An Origami-Based Medical Support System to Mitigate Flexible Shaft Buckling

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Exploiting the Nonlinear Stiffness of TMP Origami Folding to Enhance Robotic Jumping Performance

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Synthesis and characterization of polyethylene terephthalate (PET) precursors and potential degradation products: Toxicity study and application in discovery of novel PETases

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