cleaning robot project

I have a project to make a robot to clean small things around the house, but I have to make sure that after cleaning a place, he can not go there any more except when he needs to deviate from something, how i can i do it?

I can't help, but I'm joining the thread to see what answers you get. Obviously needs some kind of "mental map" and cross off the places it's been.

Interested to see what comes up.

I was thinking "close the door".

More info will be needed. "Cleaning small things" - so not the floor. How does that robot get around? What does it know of its environment? To what extent "can not go there any more"?