A centimeter-scale quadruped leverages curved-crease origami

Researchers led by Cynthia Sung in Penn Engineering have crafted a more simplified approach to the design and fabrication of these robots.

Centimeter-scale walking and crawling robots are in demand both for their ability to explore tight or cluttered environments and for their low fabrication costs. Now, pulling from origami-inspired construction, researchers led by Cynthia Sung, Gabel Family Term Assistant Professor in the School of Engineering and Applied Science’s Mechanical Engineering and Applied Mechanics (MEAM) Department, have crafted a more simplified approach to the design and fabrication of these robots.

A centimeter-scale quadruped robot sitting on a desk next to a a quarter for scale
(Image: Sung Lab)

Known as CurveQuad, this centimeter-scale quadruped leverages curved-crease origami to self-fold, unfold, crawl, and steer, all using a single motor. The curved creases in this technique have interesting mechanical properties as compared to more commonly used straight crease designs because they induce bending in a folded sheet. Energy, stored in the folding of creases and in the bending of panels, allows for controlled, reversible, and complex motions using fewer actuators.

“The robot is able to do these things because it uses curved creases,” says Sung, also a member of Penn’s General Robotics, Automation, Sensing and Perception (GRASP) Lab. “Since it is simple and thus relatively cheap, we imagine that similar designs can be made in the future for rapid deployment of robotic swarms, which could be produced for dollars or potentially even cents per robot.”

The findings are published in the journal Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems. Researchers presented their work on Oct. 2 at the 2023 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2023), held in Detroit, MI.

CurveQuad’s single motor for self-folding and movement reduces the robot’s total mass and volume. The origami-inspired design also simplifies the manufacturing and assembly of a centimeter-scale robot by fabricating the entire robot, or its parts, from a few flat sheets of material, then folding it into its 3D shape, often with fully embedded electronics, actuators, and computation onboard. These manufacturing processes are also scalable to large-volume production.

Read more at Penn Engineering Today.