Flights of nearly all unmanned aircraft, or drones, have been banned over 133 U.S. military facilities due to security concerns over the use of unauthorized drones, the Federal Aviation Administration said on Friday.
Robots clean rivers and sort waste, monitor ecosystems, and inspect renewable-energy infrastructure. But even the greenest robot has an environmental footprint.
EPFL engineers have designed acoustic cavities that convert sound waves into thrust, propelling small robots and ultralight aerial vehicles without on-board actuators or electronics.