Tiny autonomous robots can now swim on their own

For decades, microscopic robots lived mostly in our imagination. Movies like "Fantastic Voyage" convinced us that tiny machines would one day cruise through the human body, fixing problems from the inside. In reality, that future stayed frustratingly out of reach. 

The reason was not a lack of ambition. It was physics. 

Now, a breakthrough from researchers at the University of Pennsylvania and the University of Michigan has changed the equation. The teams have built the smallest fully programmable autonomous robots ever created...