Uber is expanding its use of autonomous delivery vehicles with the announcement that it will soon deploy sidewalk robots developed in Miami, Florida. The six-wheeled delivery robots will come from Cartken, an Oakland-based AI company founded by a team of ex-Google engineers known mostly for deploying its vehicles on college campuses. The robots will deliver items offered by a slate of businesses in the Dadeland area of Miami-Dade County, with plans to expand into larger areas of the city and