A team of US researchers has developed a 7.8mm-sized robot that uses origami folding and magnets to move around.
The robot, which can swim through liquids and locomote across land, could one day be used in targeted medicine delivery and other micro-forms of transport.
Origami-inspired robots are not a new concept: in fact, there have been several announced by engineers in the past half-decade. But this millirobot, described in a paper in Nature Communications, is the first to be able to navigate both land and water, and need only one geometric component to move and perform functions.
The tiny robot is made from thin polypropylene film, folded using Kresling origami – a hollow cylinder made of folded triangles. Its base is a magnetic plate.
The geometric design and weighting of the robot means that, when placed under different magnetic fields, it can be coaxed into rolling, flipping and propelling itself via spinning. This lets it move around in both air and water with ease.
The millirobot can pump liquids, meaning it could be used to deliver controlled amounts of medicine to certain parts of the body. The robot can also suck up solid items via spinning and transport them to different places.
The researchers, who are based at Stanford University, US, also tested out the millirobot’s grit in a (dead) pig’s stomach. They found that the robot could navigate through the viscous organ and deliver a mock “medicine” to a specific target.
“The proposed concept of the spinning-enabled amphibious origami robot can be scaled up or down for broader applications,” write the authors in their paper.
“With advanced fabrication methods, downsized origami robots can be manufactured for biomedical environments, including blood vessels and ureters.
“In addition, the internal cavity of Kresling can be utilized to integrate different components within the robot, such as mini-cameras and forceps, enabling multiple biomedical operations, including endoscopy and biopsy.”