Zurich scientists have been building and experimenting with super small robots that can be used to help perform incredibly delicate surgical procedures on humans.

The body on these nanobots is just a quarter-millimeter in diameter (approximately the width of four human hairs), but is still advanced enough to have a retractable needle that allows it to probe and interact with the human body. And although its needle is as thin as a regular, human-sized surgical scalpel, it’s still just as sharp.

Since these robots are so small, they’re really only adept for use in minimal, non-invasive surgeries, but their size also makes them ideal for highly sensitive procedures with delicate areas of the human body, such as the eyeball.

However, their miniscule size also means they don’t have any room for a battery to power them, which is why researchers have created an alternate system that uses electromagnets places around a patient’s head to power the robot inside that person’s body. Doctors or scientists can then increase or decrease the force of the electromagnets to control the nanobot by pushing or pulling it through the person’s body. This system is called The OctoMag.

Right now, this system isn’t quite ready for use on humans.

[via Mashable,, image via NanoGlass]