Norman Yee, an American elected official in San Francisco, has recently proposed legislation that would prohibit autonomous delivery robots -- which includes those with a remote human operator -- on public streets in the city. In a statement provided to Recode, Yee said, "our streets and our sidewalks are made for people, not robots." He also worries that many delivery jobs would disappear. The proposed legislation is causing a headache for one high-tech startup in particular. The tech company is called Marble, which uses bots fitted with camera and ultrasonic sensors to deliver small packages and food within a one or two mile radius. The delivery robots themselves travel at a walking pace and use cameras and sensors to avoid pedestrians and navigate pavements. The Guardian reports: San Francisco police commander Robert O'Sullivan is in favor of the legislation, fearing the robots could harm children, the elderly, and those with limited mobility. "If hit by a car, they also have the potential of becoming a deadly projectile," he told a local TV station. Marble CEO Matt Delaney says these fears are unfounded. "We care that our robots are good citizens of the sidewalk," he says. "We've taken a lot of care from the ground up to consider their need to sense and intuit how people are going to react."