An army of a million microscopic robots

摘要

TROOPS of mini walking robots have been created that could enable scientific exploration at a microscopic level. People have made microscopic robots before, but these haven't been able to move by themselves, says Marc Miskin at the University of Pennsylvania. That is partly because of a lack of small enough actuators, which are required for movement, such as bending a leg. Miskin and his colleagues have developed an actuator made of a thin layer of platinum. The robots have four tiny actuators as legs, each connected to a different solar cell on the back. This enables the legs to bend if the solar cells are hit by laser light and propels the square metallic bodies forwards (Nature, d0i.org/d7kt). By shooting the solar cells in sequence with a laser, you trigger the legs to contract to move in the way you want, says Miskin. Through a process similar to that used to produce circuit boards, Miskin and his team made more than a million microrobots, each of which is smaller than a tenth of a millimetre and only visible under a microscope.