Abstract
Elegant 3D origami structures from a planar sheet have been presented by incorporating curved folding into the design. Sometimes they look like sculpture, and a new genre called curved origami are now being formed. However, relation between the curved origami and traditional origami using straight creases is not clear in theoretical bases. We construct curved creases consisting of very short (tending to infinitesimal) straight hinge like creases. In the present report, some origami samples for circular tubes surfaces and conical surfaces are introduced. In the second half, a fundamental design method of such forming collar in vertical form-fill-seal machine is presented by using curved folding without elastic strain.
