In recent years, origami has become a focus and an inspiration for scientists developing light, foldable robots. But these delicate prototypes are often hampered by a serious design challenge: the need for a hefty battery to provide electricity.
A group of researchers from the Wyss Institute at Harvard have bypassed the issue by engineering tiny robots that don’t need a battery at all. Instead, their prototypes are powered wirelessly. They join a number of scientists–including those at MIT–who want to invent not only the robots of the future, but the medicine of the future.
These little robots are powered by an electromagnetic field, similar to how you would wirelessly charge a cell phone. By changing the frequency of the magnetic field, the researchers are able to precisely control the exact movement of their prototype. For instance, one triangular robot that’s no bigger than a quarter is composed of three triangular pieces of thin plastic, attached with hinges to a middle triangle that has a circuit. The hinges are controlled by coils of a metal called “shape-memory alloy,” which changes its form when it’s exposed to heat. When an electric current starts running through the central circuit, these coils heat up and contract, causing the three triangles to fold up toward the center of the robot. When the current stops, the hinges return to their flat state.
While the origami-inspired joints can only contract and relax, the Wyss team was also able to construct a robot that, using the same mechanism, can bend to the left and right and open and close a small claw.
Mustafa Boyvat, a postdoc at the Wyss Institute and Harvard’s engineering school and the lead author on the paper, tells Co.Design over email that this kind of technology is particularly relevant in medicine. “Having small wireless medical tools for some tasks can bring a lot of advantages for patients and doctors,” he says.
Because these types of bots are wireless and can be accurately controlled using nothing but a magnetic field, they could be swallowed by or injected into patients. Then, they could perform tasks inside the body–like filming images or holding tissue, under the control of a professional.
Besides the pincher robot, Boyvat’s team also built a paper ship in a bottle to show that their discovery can scale up. On an even larger scale, it could let smart objects in the home communicate wirelessly and without power. Boyvat also imagines there may be applications in the creative world, though they’re likely far away: “Designers [and] artists can use this technology to produce dynamic origami structures that can be powered and controlled wirelessly,” he says.