Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 25, 2025 - November 29, 2025
As for the candidate of a novel smart structure with variable morphology, present study examined the self-extraction of origami folded shape memory polymer (SMP) sheet. We used a flat polyurethane SMP sheet of which the glass transition temperature was 55℃. The origami was prepared by folding the sheet in viscous state at temperatures higher than the glass transition temperature, and the elastomeric deformation was set into the glassy state at room temperature. It was observed that the SMP origami was unfolded spontaneously to be back to the flat sheet of original shape at temperature of the viscose state, which revealed typical shape memory effect of SMPs. Starting from the simple origami with one-fold line, origami structures with two folding lines were examined. The sequence of extraction in the fold lines was observed and the mechanical origin of the self-extraction was examined in terms of the strain relief around folding lines and nodes.