The innovation sets the stage for a new generation of tiny devices that can track bacteria, sniff out chemicals, destroy pollutants, perform microsurgery and remove plaque from arteries.
The "brain" of the new robot is a complementary metal-oxide semiconductor (CMOS) clock circuit that contains 1,000 transistors, plus an array of diodes, resistors and capacitors. The integrated CMOS circuit generates a signal that generates a series of phase-shifted square wave frequencies that set the robot's gait. The robot legs are platinum-based brakes, and both circuits and legs are powered by photovoltaics.
The new robot is only one-thousandth the size of larger robots mounted on onboard CMOS electronics and can travel at speeds of more than 10 microns per second.
Researchers have previously developed tiny robots that can crawl, swim, walk and fold themselves, but always with "threads" connected together. To generate movement, the wire is used to provide an electric current, or the laser beam must be focused directly on a specific spot on the robot.
"Previously, we had to manipulate these 'lines' to get any kind of response from the robot." "Now that we have these brains, it's like untangling a string from a marionette, like Pinocchio having consciousness," said Itai Cohen, a professor of physics at Cornell University.