Engineers from the Advanced Institute of Industrial Technology in Tokyo have developed a novel biometric automotive anti-theft system that uses the unique shape of your butt to identify you.

The driver’s seat is fitted with 360 sensors that measure pressure according to a scale of zero to 256. Each reading is plotted to create a 3-D image — essentially a topographic map of your ass — used as a personal identifier. Anytime someone gets behind the wheel, the system analyzes the shape of their behind. If it isn’t your rear end in the seat, the car isn’t going anywhere.

The engineers behind the gadget say it was able to identify six different testers with 98 percent accuracy. We can’t read the report (.pdf) because it’s in Japanese, so we don’t know how the system might react to, say, having a wallet in your pocket or packing on a few pounds during the holidays.

Business newspaper Nikkei says the researchers hope to commercialize “a highly reliable anti-theft system” through a collaboration with automakers within two or three years.

Image: Advanced Institute of Industrial Technology