Uber has unveiled plans to trial autonomous'sidewalk robots' to deliver food to people's doorsteps. The US ride-hailing giant announced the idea as part of a raft of new features and services for its customers. These included an option for those in certain cities to specifically request a ride in an electric car, which Uber said was part of its global commitment to becoming a zero-emissions mobility platform by 2040. Comfort Electric is now available in Los Angeles, San Francisco, San Diego and Dubai, with more cities to come soon. The sidewalk robot concept is one of two autonomous delivery pilot programs being trialled in California.