Microscopic robots 'walk' thanks to laser tech

These robots, roughly the size of paramecium, provide a template for building even more complex versions that utilize silicon-based intelligence, can be mass produced, and may someday travel through human tissue and blood. The collaboration is led by Itai Cohen, professor of physics, Paul McEuen, the John A. Newman Professor of Physical Science and their former postdoctoral researcher Marc Miskin, who is now an assistant professor at the University of Pennsylvania. The walking robots are the latest iteration, and in many ways an evolution, of Cohen and McEuen's previous nanoscale creations, from microscopic sensors to graphene-based origami machines. The new robots are about 5 microns thick (a micron is one-millionth of a meter), 40 microns wide and range from 40 to 70 microns in length. Each bot consists of a simple circuit made from silicon photovoltaics -- which essentially functions as the torso and brain -- and four electrochemical actuators that function as legs.