ESA’s Philae comet lander has once again gone silent. According to the space agency, the first spacecraft to make a soft landing on a comet lost radio contact with the Rosetta orbiter mothership on July 9.
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.