Tech & Science

CU-Boulder ‘photo origami’ proposal
wins $2 million NSF grant

The art of origami has inspired children and artists all over the world because of the amazing objects that can be created by folding a simple piece of paper.

Now an engineering research team at the University of Colorado Boulder has won a $2 million grant from the National Science Foundation to develop a light-controlled approach for “self-assembly” mechanisms in advanced devices based on the same principles.

Known as “photo origami,” the idea is supported by NSF’s Emerging Frontiers in Research and Innovation program, which supports interdisciplinary teams working on rapidly advancing frontiers of fundamental engineering research.

CU-Boulder associate professor of mechanical engineering Jerry Qi will lead the team developing the photo origami technique. Collaborators will include CU faculty Robert McLeod of electrical engineering, Kurt Maute of aerospace engineering sciences and Elisabeth “Beth” Stade of mathematics, along with Patrick Mather of Syracuse University.

The ability to transform a flat polymer sheet into a sophisticated, mechanically robust 3-D structure will enable new approaches to manufacturing and design of devices from the microscopic to centimeter scales, according to the team. Examples include using extremely low-weight, high-strength materials to create micro-electromechanical systems with complicated 3-D architectures that can be used for microscopic sensors such as antennas or microphones, and miniature robotic devices for environmental monitoring.

Present barriers to the development of folding and unfolding mechanisms stem from the lack of understanding of scaling laws that allow researchers to generalize results obtained at various size scales, the inability to easily cause matter to “reorient” itself to achieve the desired folding patterns, and challenges in automated, sequential folding.

To overcome these challenges, the CU team will make use of recent fundamental advances in the control of polymer architecture through light-triggered chemical reactions.

“One has to accurately control how much deformation a material should have in order to obtain a precise folding angle and to determine where to fold or stop folding in order to avoid interference in the folding path and form the desired structure,” said McLeod, who will use the interaction of light with material deformation to develop optical waveguide transistors.

In this new form of logic circuit, light triggers the deformation of a soft polymer, which in turn switches the light on or off. In this way, the optical waveguide transistor will enable a structure to be pre-programmed with a folding pattern through a sequential set of switching events controlled by the shape of an origami sheet.

In recent years, CU researchers and their collaborators have made significant progress in using light to control and alter the structure of a polymer. They are able to both bend and stiffen polymer structures and to develop new, soft, shape-memory composite materials through photo-initiation techniques. Shape-memory composites are “smart” materials that have the ability to return from a temporary, deformed shape to their original shape when induced by a trigger.

In addition, the team will work with the local school district to provide research and educational opportunities for K-12 students and teachers.