Researchers have created new cell-sized insect-shaped robots with some pretty nifty properties. These little devices are wirelessly powered and can survive and walk in harsh environments. Best of all, they are so tiny they can be injected through a needle.
"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 devices with colleagues professors Itai Cohen and Paul McEuen and researcher Alejandro Cortese at Cornell University.
A brain and organs
The new technology developed by the researchers is a nanofabrication technique that can convert a 4-inch silicon wafer into a million microscopic robots in just weeks. These tiny robots are each a mere 70 micron long.
To put it into perspective, the new devices are the width of a human hair. Despite their minuscule size, their bodies have been equipped with the equivalent of a brain and organs.
These systems are made of a superthin skeleton of glass mounted with a thin layer of silicon that carries electronics components and two or four silicon solar cells.
"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.
The robot's four legs are made from a bilayer of platinum and titanium applied using atomic layer deposition. "It's like painting with atoms," explained Miskin.
"The legs are super strong. Each robot carries a body that's 1,000 times thicker and weighs roughly 8,000 times more than each leg."
In order to power these minuscule robots, the researchers simply need to shine a laser on one of their solar cells. Each solar cell has the task of achieving the contraction or relaxation of the front or back legs.
Smart versions desired
Now, teams at Cornell and Pennsylvania are attempting to make smart versions of the robots. These will be equipped with onboard sensors, clocks, and controllers.
Miskin is also working on new energy sources for the minuscule devices because the laser option limits the robot's control to a fingernail-width into tissue. Some of the alternatives explored are ultrasound and magnetic fields.
These would allow the robots to travel deep into the human body. If this seems far fetched, it should be noted that the devices are already performing well once injected.
"We found out you can inject them using a syringe and they survive -- they're still intact and functional -- which is pretty cool," Miskin concluded.