Measuring tread depth with light-spot analysis

A suitable and safe tire strongly affects safety while a car is driven. However, when the tire is worn and the tread has become shallow, it can cause the driving car to slide easily and reduces safety. Accordingly, many governments, including Taiwan, stipulated that the depth of the tread must be greater than 1.6 mm; obviously, developing a convenient method to measure tread depth is a valuable technology. This paper proposed a non-contact measuring depth method, which is based on light-spot analysis. The experimental results showed that the proposed method could measure tread depth correctly.