While the Japanese art of origami has been “a rich source of inspiration” for scientists working to construct such 3D forms, the limitation to simple shapes has held up development of new applications in areas such as biomimetic systems, soft robotics and mechanical meta-materials, especially for structures on small length scales where traditional manufacturing processes fail. Now, however, a team led by polymer scientist Ryan Hayward has developed an approach that could open the door to a new wave of discoveries.

He and Junhee Na, Arthur Evans and Christian Santangelo at UMass Amherst, with several other collaborators, have found a way to make reversibly self-folding origami structures on small length scales using ultraviolet photolithographic patterning of photo-crosslinkable polymers.

The UMass Amherst team uses a maskless lithographic technique based on a digital micromirror array device to spatially pattern the crosslinking of the polymer films, and then dissolves away the uncross-linked regions with a solvent. By directly patterning the polymer films, rather than using a traditional photolithographic approach based on a photoresist layer, it is possible to pattern multiple layers of polymers with widely contrasting material properties using relatively few processing steps.

In biomedicine or bioengineering, the new approach may help in developing advanced self-deploying implantable medical devices, or in guiding the growth of cells into complex tissues and organs.