Researchers at Cornell University have created the smallest walking robot to date. Its mission is to be small enough to interact with visible light, yet still be able to move independently, allowing it to be moved to a specific location (e.g. a tissue sample). The smallest structure in the body.
The team’s paper, “Magnetically Programmed Diffractive Robotics,” science.
“A walking robot small enough to interact with light and effectively shape it takes the lens of a microscope and places it directly into the microworld,” said Paul McEuen, professor emeritus of physics, who led the research team. “You can do close-up imaging in a way you could never do with a regular microscope.”
Cornell scientists already hold the world record for the world’s smallest walking robot, measuring between 40 and 70 microns.
Itai Cohen, a professor of physics and co-author of the study, said the new diffraction robot “will blow that record out of the water.” “These robots are between 5 microns and 2 microns. They’re very small, and by controlling the magnetic fields that guide their movements, we can make them do whatever they want.”
For the first time, diffractive robotics uses imaging technology that relies on visible light diffraction (the bending of light waves as they pass through or around an aperture) to connect untethered robots. Imaging techniques require an aperture whose size is similar to the wavelength of light. For the optics to work, the robot must be at that scale, and the robot must be able to move on its own to reach the image target. The Cornell team achieved both goals.
Controlled by magnets that make a pinching motion, the robot can advance inch by inch on a solid surface. They can also “swim” through fluids using the same motion.
The combination of maneuverability, flexibility and subdiffractive optics has led to significant advances in robotics, the researchers said.
This research was made possible by the Cornell Center for Materials Research, the National Science Foundation, and the Cornell Nanoscale Science and Technology Facility.
