Using digital light processing (DLP), a relatively new 3D printing method, researchers at Georgia Institute of Technology (Georgia Tech) have created origami structures that hold significant weight and remain durable when folded repeatedly. The structures are composed of a single polymer. They do not require assembly, making this technique a one-step approach to fabricating complex origami structures. Georgia Tech postdoctoral fellow Xiao Kuang demonstrates the compressability of origami structures created through digital light processing 3D printing. Courtesy of Christopher Moore, Georgia Tech. DLP creates structures by printing successive layers of a liquid resin that is then cured by UV light. The researchers developed a new resin that, when cured, is very strong. “We wanted a material that is not only soft, but can also be folded hundreds of times without breaking,” said professor H. Jerry Qi. The photocurable resin is used with hinge-panel elements to form the origami structures. The panels make up the bulk of the structure. The hinges, which occur along the creases where the origami structure folds, allow repeated folding because they are made of a thinner layer of resin than the larger panels. The team used DLP to print several structures ranging from individual origami cells to a complex bridge composed of many zippered tubes (origami structures that can support weight and be refolded). Tests showed that the origami structures were capable of carrying about 100 times the weight of the structure, and could be repeatedly folded and unfolded without breaking. This is a closeup of an origami structure created through digital light processing 3D printing. Courtesy of Christopher Moore, Georgia Tech. The 3D-printed origami assemblages were found to show acceptable strength and load-bearing capacity for engineering applications. What we have here is the proof of concept of an integrated system for manufacturing complex origami. It has tremendous potential applications,” said professor Glaucio H. Paulino. When Paulino first reported these structures in 2015, they were made of paper and required gluing. The DLP-printed origami structures mimic the behavior of their paper counterparts. Paulino’s team recently created a new origami pattern that he has been unable to physically make because it is so complex. “I think the new system could bring it to life,” he said. The researchers are working to make the printing even easier, while also exploring ways to print materials with different properties. The research was published in Soft Matter (http://dx.doi.org/10.1039/c8sm01341a).