Ohio State researchers have discovered a way the ancient practice of paper folding might progress 21st-century medicine: origami robots.

The robots are designed to be used to treat ailments inside the human body. Using a magnetic field, the researchers can control the structure of the robots as they see fit once they enter the human body — an advantage lost with other, more invasive methods of delivering medications, Shuai Wu, a second-year doctoral student in the Soft Intelligent Materials Laboratory at Ohio State and a leading author of the study, said.

“It’s a pretty flexible way and a reliable way to make the whole structure deform as we want,” Wu said.

Wu said another advantage to the magnetic control of the robots is that they don’t require a power source or other external connections such as wires and tubing, meaning their size can be significantly reduced. Renee Zhao, assistant professor of mechanical and aerospace engineering and corresponding author of the paper, said the robots could deliver medications in all forms, with the amount of treatment distributed dependent on its concentration more than the size of the robot itself.

The research, released in a study published Sept. 14 in the journal Proceedings of the National Academy of Sciences, is in partnership with Georgia Tech and funded by the National Science Foundation, according to a Sept. 21 news release. 

Zhao said while Georgia Tech researchers are focused on studying the origami pattern itself, Ohio State’s team is focused on assembling the robots and finding ways to control them. 

To build the robots, Zhao said researchers create the shape of the origami, cut out the patterns, then assemble them. Placed between the folded patterns are magnetic disks, created with soft magnetic polymer, which takes about two hours to assemble.

Jun Nishikawa, a fourth-year in mechanical engineering currently working on even smaller versions of the robots, said this shape of origami allows for the structure to be extended and retracted while keeping stable. 

“If you actually hold it in your hand and push on it, it kind of snaps into place. Sort of like pressing a button,” Nishikawa said.

Zhao said this soft material is preferred when making robotic systems because it provides a lot of flexibility when manipulating structures. 

The material attempts to mimic animals in nature with a greater range of motion, such as squids or earthworms, Zhao said. Such movement would allow the robots to move themselves easily within the body.

“We’re trying to make the material intelligent,” Zhao said. “So, the material itself is not just only a material, it’s also a computer. This is what we’re trying to embed into this origami system.”

Wu said one of the next steps will be scaling up the magnetic field that interacts with the origami robots, so it will be large enough to maneuver them throughout the entire human body.

For later health care applications, Wu said the robots need to be compatible with the human body, so the current paper material for the origami shape will be switched to a polymer that isn’t harmful to living tissue. He said the robots will also be scaled down so that they can easily navigate through confined spaces within the human body.

Further research will evaluate the safety of the robots, Zhao said, with emphasis placed on considering where to surgically insert and remove the robots to minimize invasiveness.

Beyond dispensing medications for treatments, the researchers are thinking of other ways the robots can help medical services.

“We can add some pH sensors or other types of sensors to the robot, so that when it navigates through the human body, it will sense the surrounding environment and tell us whether there will be a sign of the disease,” Zhao said.