A researcher from Case Western Reserve University has turned origami into a patent-pending soft robot that may one day be used on an assembly line, in surgery or even outer space.
TWISTER, an origami-inspired soft robot. (Russell Lee)
Kiju Lee, Nord Distinguished Assistant Professor of Mechanical and Aerospace Engineering, has moved from paper robotics to 3D printed models that bend, contract, extend and twist. The mechanism is called TWISTER (Twisted Tower Robot).
TWISTER was inspired by the origami twisted tower that was originally designed by Japanese artist Mihoko Tachibana, which uses multiple origami segments that form a tower structure. This origami design was reinvented for various potential applications in robotics and manufacturing.
In her earlier paper-folded structure work, Lee’s team added three small versions of the towers to one end of the larger tower and manipulated them to grasp like three fingers. When picking up and moving eggs and ripe fruit, Lee’s team found that when excessive force was applied, the fingers absorbed the extra force by distributing it and deforming.
This quality demonstrates the design’s potential for manipulating all kinds of fragile objects without requiring force-based sensing and interacting with humans without safety concerns.
Lee has successfully converted the TWISTER designs into models for 3D-printing. This work allows for fabrication of complex origami-inspired design via 3D printing.
"Among the possibilities for this robot are fragile-object manipulation and direct human-robot interaction because these robots are soft and safe," said Lee, "TWISTER is very different from rigid body robots."
TWISTER is made from multiple layers of regular polygons—triangles, hexagons or octagons—forming a tube-like shape of a tower.
Lee used cable-based actuation to control the robot. There are different approaches that are being explored, like using Shape-Memory-Alloys. The motions can make a tower lying on its side crawl.
The hard-bodied robots are typically separated from people during the manufacturing process for safety reasons.
"Because this robot can be made with soft materials," said Lee, "it could be safe to use on an assembly line right next to people."
Lee and physicians have been exploring ways to miniaturize the robot so it can be inserted in the body for minimally invasive surgeries.
"Laparoscopic surgery often requires some rigid pieces, and movement to control them from the outside causes stress on the tissues," Lee said.
She and her team have also been exploring these origami robots for space applications, like a space arm.
"To put anything into space, volume and weight are critical, because of the cost of rocket transport," Lee said. "This robot is fully collapsible and, compared to a rigid arm, light and compact."
Lee will present the study at the IEEE/RSJ International Conference on Intelligent Robots and Systems in Vancouver on Sept 27.
