If you ever tried your hand at origami and thought it was too complicated, researchers at the Georgia Institute of Technology and Peking University got your back. They developed a way to create self-folding origami structures using a PowerPoint slide, a projector and photocurable liquid polymers.
To make the origami, the researchers first designed a grey-scale pattern with software, in their case PowerPoint. The pattern is then projected onto a layer of liquid polymer resin with an ordinary LED projector. The light irradiation cures the resin continuously from the side directly exposed to the other side. This causes the resin to shrink in the illuminated place, bending the film along the light path by itself.
How much the material bends, depends on the amount of light exposure, both in time and intensity. In the study, light was shone onto the film for five to ten seconds, which produces a film about 200 microns thick. To make the most complex origami structures, the researchers shine light onto both sides of the structures.
Using this technique, the researchers were able to create various, complex structures, such as flowers, cranes, and Miura-ori folding. For now, they are only able to create small structures of about a centimetre (half an inch) in size, as the method mainly deals with thin polymer films.
The researchers used poly(ethylene glycol) diacrylate in this demonstration, coloured with an orange dye, but the technique should work with a broad range of photocurable polymers.
This method could be used to fabricate soft origami machines, mechanical metamaterials, as well as some capsule structures. As the material is not strictly confined, it could be applied to many comparable material systems.
For another way to create self-folding origami, click here.
Photos: Rob Felt / Georgia Tech