Tiny robot can be made to ‘walk’ using pulsed laser beams

A breakthrough robot can be made to walk by charging up its legs with pulsed laser beams, allowing it to move without the need for an onboard battery. Unfortunately, you’ll probably never get to see it with your own eyes.

Don’t feel too bad, though: At just 5 microns thick, 40 microns wide, and a maximum of 70 microns in length, even its inventors need ultra-magnification technology to see it properly. (For reference, a micron is one-millionth of a meter or, approximately, 1/100 the thickness of a sheet of ordinary paper.)

“The last 50 years have led to incredible developments in the miniaturization of electronics,” Itai Cohen, professor of physics at Cornell University, told Digital Trends. “Today, we can manufacture an entire Intel 4004 chip in an area equivalent to the cross section of a single strand of human hair. The ability to make chips at this scale opens the door to making tiny robots. But there was a missing piece: We did not know how to make the moving robotic appendages at this scale.”

In this latest micro-robot demonstration, the researchers developed actuators that are just 10 nanometers thick, and can form bends that are only a few microns in radius within a fraction of a second. Each tiny robot is composed of a simple circuit that is made up of silicon photovoltaics and four electrochemical actuators for legs. Powering the legs is a matter of toggling the laser back and forth between front and back photovoltaics.

Laser microbot
Cornell University

Future micro-surgeons?

Right now, it’s still early days for the research. The robots qualify as robots — but, perhaps, only barely. “The next big step is to add more complex circuits to make more advanced robots,” Marc Miskin, who worked on the project as a postdoctoral researcher and is now an assistant professor at the University of Pennsylvania, told Digital Trends. “What can they sense? How do we incorporate feedback or onboard timing? Can they be programmable? The good news is that the semiconductor industry has already developed a lot of technology to go after these questions. We’re all optimistic that these tiny machines may evolve rapidly.”

When they do, the investigators have some big plans for them. Or, rather, some very, very small plans. “An exciting application — though still far in the future — is [for the robot to act] as a microsurgeon,” Paul McEuen, professor of physical science at Cornell, told Digital Trends. “Imagine a swarm of tiny robots at the edge of a cancerous tumor that, cell by cell, sense the health of tissue and then destroy any cancer they find. [This] will require the integration of sensors, intelligence, and careful feedback, but it should be possible.”

A paper describing the work was recently published in the journal Nature.

Editors' Recommendations