University of Pennsylvania’s Ian Scheffler reports that researchers have built the tiniest programmable, autonomous robots ever.

Rob Egan provided feedback on the work of editor Gaby Clark. Critical remarks from the editors With thanks to Marc Miskin of Penn Microscopic swimming machines that can perceive and react to their environment autonomously, run for months, and cost about a penny each were constructed by researchers at the University of Pennsylvania and the University of Michigan. They are the tiniest completely programmable, autonomous robots in the world.

Each robot is less than a grain of salt in size, measuring approximately 200 by 300 by 50 micrometers — hardly discernible to the naked eye. Robots that function at the microscopic level have the potential to revolutionise healthcare by tracking the condition of individual cells and manufacturing by assisting in the creation of microscale gadgets.

The light-powered robots have tiny processors on board that allow them to learn complicated patterns, detect environmental temperatures, and change their routes appropriately.

The first totally autonomous, programmable robots of this scale, as described in Science Robotics and Proceedings of the National Academy of Sciences, function without tethers, magnetic fields, or external control similar to a joystick.

“We’ve made autonomous robots 10,000 times smaller,” remarks Marc Miskin, assistant professor in electrical and systems engineering at Penn Engineering and senior author of the publications. “That opens up an entirely new scale for programmable robots.”