Waste-sorting robots that have been learning their job while wandering through Google offices can now effectively sort items in bins into recycling, compost and rubbish.
One way of teaching machines to perform tasks is by reinforcement learning, in which a robot is told what a successful outcome looks like and is left to figure out how to achieve it by trial and error and a system of feedback, gradually building up an optimal model of what to do.
Normally, a robot starts to learn how to complete a task in this way from scratch, but to kick-start this process …