Well I never… Researchers in Iran are throwing life belts into the sea with a lifeguard drone. In seaside tests the Pars robot took just 22 seconds to bring a belt to a pretend struggling swimmer 75 metres from the shore. The human lifeguard took 90 seconds to reach him.
The drone currently needs a human operator, but its developers are aiming for it to recognise distressed swimmers on its own, drop them a life belt and return to base. Hurray! For once a drone story that doesn't fill me with dread.