LEGO Machine Tests How Small A Gap A Mouse Can Fit Through

It’s common knowledge that mice can fit into tight spaces. But how tight exactly? Canadian engineer Matthias Wandel created an experiment to see exactly how small a gap a mouse can fit through.

Using a Lego kit his work purchased for him and a Rasberry pi circuit board, Mattias created a tricky little machine with a door that the computer closes a little bit more every time the mouse leaves the area. It first detects the mouse using a light sensor and then waits for the animal to leave before ratcheting the door closed a millimeter more each time.

As it turns out, it seems a mouse can squeeze into a gap about 11 to 12 millimeters wide. Well, at least this particular mouse could. If his head could fit within a space, his body could squeeze through, no matter how many seeds he had packed his stomach with.