Researchers have developed the tiniest walking robot to date. Its aim is to be small enough to engage with visible light waves while still moving autonomously, allowing it to navigate to specific areas—such as within a tissue sample—to capture images and assess forces at the level of some of the tiniest structures in the human body.
Cornell University researchers have developed the tiniest walking robot to date. Its aim is to be small enough to engage with visible light waves while still moving autonomously, allowing it to navigate to specific areas—such as within a tissue sample—to capture images and assess forces at the level of some of the tiniest structures in the human body.
The researchers detailed their findings in a paper titled “Magnetically Programmed Diffractive Robotics,” which was published in Science.
“A walking robot that’s small enough to manipulate and effectively alter light essentially brings the capabilities of a microscope lens into the microscopic world,” explained Paul McEuen, professor of physical science emeritus and leader of the team. “It can enable close-up imaging in ways that a conventional microscope simply cannot.”
Cornell scientists already hold the world record for the smallest walking robot, measuring between 40 to 70 microns.
The new diffractive robots promise to surpass that record significantly, according to co-author and physics professor Itai Cohen. “These robots measure between 5 and 2 microns. They are incredibly small, and we can manipulate their movements as we wish using controlled magnetic fields.”
For the first time, diffractive robotics links untethered robots with imaging methods reliant on visible light diffraction—the phenomenon where light waves bend when passing through an aperture or around an object. This imaging approach requires an aperture size that is similar to the wavelength of light. To ensure this optical method works effectively, the robots must be on a comparable scale, and they also need the ability to navigate independently to reach their imaging targets. The Cornell team has successfully met both criteria.
Using a pinching motion controlled by magnets, the robots can crawl forward on a solid substrate. They can also move through liquids in a similar fashion.
This blend of agility, adaptability, and sub-diffractive optical technology represents a major advancement in the domain of robotics, according to the researchers.
This research received support from the Cornell Center for Materials Research, the National Science Foundation, and the Cornell NanoScale Science and Technology Facility.
