Rapid prototyping for nondevelopable discrete and semi-discrete surfaces with an overconstrained mobility.

Abstract

In recent years, technical folding, also known as structural origami, has been developed and implemented in many fields and applications to a wide range of materials. As many techniques are inspired by computational origami, their output is in most cases a three-dimensional mesh that can be developed without stretching or tearing in a planar mesh that represents a planar sheet of material. This is not only helpful in the fabrication of large spatial structures, but also in the design and development phase where the models can easily be built from planar sheets of paper. For geometries that cannot be folded from a single sheet, an assembly strategy is needed that allows for a high accuracy of the final model. We present a solution for the model making in the design phase, that uses 3D printing of a hinge that can be assembled with a simple snapping mechanism to facilitate the model making process. Based on the special class of T-hedral surfaces, the authors will show examples and methods for discrete and semi-discrete models with an overconstrained mobility. Therefore, the strategy will be shown and explained for straight- and curved foldlines, respectively. Although STL printers are becoming more popular, the focus lies on FDM printers as they are currently more commonly used in design and engineering offices, as well as by design- and architectural students.