South Korean scientists have adapted a navigation system from Cruise missiles to build a robot vacuum cleaner that can find its way around a room day or night, New Scientist reports in next Saturday’s issue.

Robot cleaners usually keep track of their position by measuring how far their wheels have turned. But if the wheels slip on a parquet floor or on carpet pile, the cleaner gets confused.

The patented device built by researchers at Samsung gets around this by placing a video camera and infrared detector on top of the cleaner, giving it normal and infrared vision of the room.

The robot’s computer continually compares this picture with a wide-angle photograph of the room in its memory. More here.