I was at Menards a while ago, they had a robot floor scrubber running up and down the aisles. Had a "teddy bear" sitting in the drivers seat. I had to watch it working, testing some to see how close it would get to me before stopping. About 10 feet, ≈3 meters, was as close as it got. Walking up to it from behind about the same distance, it would stop. I did talk with a guy who saw me "teasing" the robot. He said it has a map of the floor plan in memory, so it just drives around, not bumping into anything or anyone. The store is divided in sections, so the machine focuses on one section at a time, when it has finished that, moves to another, if the batteries get low, it heads back home.