Researchers at the University of Pennsylvania created tiny micro-robots that can be injected through a hypodermic needle and into the human body. It is said to help in mapping the brain, monitoring the vital signs and in performing other tasks like drug delivery.

The researchers were able to develop these micro-robots with the use of a nanofabrication technique. This technique allowed them to turn a 4-inch specialized silicon wafer into a million microscopic robots in just weeks and at a low cost.

"When I was a kid, I remember looking in a microscope, and seeing all this crazy stuff going on. Now we're building stuff that's active at that size. We don't just have to watch this world. You can actually play in it," said Marc Miskin, who developed the nanofabrication techniques with his colleagues' professors Itai Cohen and Paul McEuen and researcher Alejandro Cortese at Cornell University.

"The really high-level explanation of how we make them is we're taking technology developed by the semiconductor industry and using it to make tiny robots," said Miskin.

Each of the legs of the robot is formed from a bilayer of titanium and platinum. The platinum is applied using the atomic layer deposition.

"The legs are super strong," said Miskin. "Each robot carries a body that's 1,000 times thicker and weighs roughly 8,000 times more than each leg."

Each micro-robot is the width of a human hair, it is wirelessly powered, and it can walk and survive harsh environments. The micro-robots are solar powered, and they are controlled by a laser light that is transmitted to either two or four silicon solar cells that are on top of the robot's skeleton.

Powering the micro-robots in this way means that the robots can only operate near the surface of the body. Researchers want to expand, so they are looking into new energy sources, including magnetic fields and ultrasound, that would help enable the micro-robots to travel to other areas of the human body.

Researchers are also currently working on smart versions of the micro-robots with clocks, onboard sensors, and controllers.

"We found out you can inject them using a syringe and they survive -- they're still intact and functional -- which is pretty cool," Miskin said.

Nanobots are predicted to become a part of medicine in the future. They remove the need for invasive procedures, and they enable smart medicine by delivering drugs to the parts of the body and by performing repairs and diagnosis. Micro-robots also have the potential to monitor patients, with doctors constantly assessing the patient via sensors within the human body.