Large Scale Curved Folding Mechanisms

Abstract

Curved Folding as a method to generate structures with bent plates is a widely used design strategy in many fields. Even though the digital approaches in curved folding and active bending are constantly evolving, the materialization of these structures in a larger scale is the current bottleneck. This is obvious for materials that are not foldable due to their material behavior as e.g. wood. Therefore, we introduce a method with the aim to simplify the construction of large curved folded structures from wooden sheet material.

Compared to folding systems with straight fold lines, curved fold lines allow for the reduction of folds as well as the number of assembled pieces. In the current process folded structures are assembled from cut pieces to a “folded configuration” [1]. This strategy applied to structures with curved fold lines requires, that the individual parts need to be bent before they can be connected. This makes the assembly process a very complex one [2].

In this paper, the authors will describe a method to develop foldable structures from wooden boards. The focus lies on the development of foldable systems with curved fold lines in combination with sheet material. The use of curved fold lines causes bending of the sheet material adding the advantages of active bending [3] to the system. The authors will also show the constraints of the concept of digital paper and the limited sheet size of timber sheet material. In the presented approach, the authors describe the fabrication of complex folding mechanisms assembled from CNC milled parts in flat state, connected with a fabric hinge and folded to a stable three-dimensional configuration.