Folding of cylinder

Abstract

This report presents the research and analysis of folding an extended cylindrical structure into a condensed cylinder through engraving repeatable, triangulated patterns onto the surface of the structure. Success and development in this field could enhance the capabilities of the folding cylindrical structures. Origami, a method to achieve compactness, is exploited by folding the materials along their pattern embossed perimeter. An investigation is needed to find out the behaviour of each origami pattern in terms of compressive energy. Four cylindrical patterns (Design A, B, C and D) were chosen. Parameters of each pattern are specified by the number of sides (N), the lengths of the dimensions and the angles α and β. Polypropylene has been chosen as the building material. Patterns were engraved on the polypropylene and experiments are conducted on Instron 5565 tester to examine the mechanical energy required for compression of these patterns and its relationship with the number of sides and length of fold lines. Three results have been obtained from the conducted experiments. Firstly, findings show that the load increases with the number of sides of the cylindrical prototypes. Secondly, different patterns with the same number of sides require different compression loads. Lastly, there is a proportional relationship between the folding length and mechanical energy involved in the compression process.

Keywords: folding, cylinder, triangulated, origami, polypropylene