Now that speed cameras use is established in Europe and parts of the US, the concept of automated ticketing is beginning to expand far beyond moving violations. Already, automated ticketing machines are deployed in the US to hit vehicles that overstay in a parking spot by a minute or that have excessive tailpipe emissions. The newest addition to this growing list is camera that scans the tires of passing cars and mails tickets if the depth of the tire tread is deficient by a fraction of an inch. Although not currently deployed, the German company ProContour hopes to sell this system to state and local governments looking for a way out of tight budget situations with a positive, pro-safety message.

"Car tires are technically, the number one cause of car accidents in Germany," ProContour states on its website. "An average of four car accidents occur daily with personal injuries as the result of smooth or defective tires."

The company claims its combination of a laser and high-speed camera is capable of taking measurements at 430 million points on a tire each second. As the tire moves, the distance between the camera and the object changes allowing the system to create a three-dimensional profile of the tire. The software can then calculate not just the depth of the tread, but also whether the tire itself was designed for summer or winter use. The manufacturer has tested measurement accuracy at speeds of up to 75 MPH, but it believes the technology should work at even higher speeds.

European Union regulations authorize the imposition of a fine of up to 100 Euro (US $160) whenever the tread depth of one of a vehicle's four tires measures less than 1.6mm (0.06 inches). In Germany, drivers can also be ticketed for using tires that are "unsuitable." This means using a summer tire during the winter season carries a stiff fine -- ProContour hopes that fine will be automated.

Depending on its construction, a balding tire with low tread depth can actually have more grip in dry conditions and is not a safety hazard. That can change if it rains, however. The primary purpose of tire tread is to channel water away from the tire so that it maintains contact with the road. The combination of high water and low tread depth can lead to aquaplaning and loss of vehicle control.

ProContour's system can be used in both fixed and mobile locations and is available in an easy-to-hide configuration.