Chinese education authorities have gone high-tech to catch cheaters as millions of high-school students take their “gaokao”, the annual university entrance exam seen as key to landing a lucrative white-collar job.
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.