One fact which I had written about earlier, was that I have a “Neato XV Signature” vacuuming robot.
This robot has frequently gotten lost underneath my bed, presumably because the lower surface of my box is a canvas sheet which hangs below the sensor-line of the robot’s laser, in a way that’s curved almost parallel to the floor. The robot cannot analyze the geometry which this seems to forbid it, and can therefore sometimes end up in an endless loop. Because I want to be able to trust my robot with vacuuming 100%, when I’m not home, this error required adjustment.
Using great lengths which I have, of the magnetic boundary marker, I now also zoned off the rectangular region which is the entire underside of my bed. The robot no longer goes there.