"Robot vacuum" is not a solved problem. I've got a Roomba, and it mostly does the vacuuming, but sometimes gets "stuck" in the middle of the room, or maybe against a single wall. My Roomba's nemesis is chair legs, sometimes it gets under a 4-legged chair, but somehow can't find it's way back out. Comical, really. I enjoy my Roomba as something of a pet, but I have come to low expectations about vacuuming completeness.