Starting today, residents and businesses in Redwood City, Calif., and Washington, D.C., can get food delivered right to their doors — via robot. Starship Technologies, an Estonia-based startup created by two Skype co-founders, Ahti Heinla and Janus Friis, will put its autonomous ground-delivery robots to work delivering food with Postmates in Washington, D.C., and DoorDash in Redwood City, Calif. The six-wheeled robots are a little under two feet tall, weigh about 40 pounds empty and travel four miles per hour — walking speed. The idea is that one day soon these autonomous rovers will share sidewalk space with pedestrians on their own, but for now they’ll be accompanied by handlers — people walking alongside each robot as it makes its deliveries. The handlers will take notes on how well Starship’s robots perform and intervene if something goes wrong.