Fuzzy Ultrasonic Testing System with Columnar Rod

This paper describes an ultrasonic testing system with a columnar rod. The general ultrasonic probe is affected by transmission pulse for measurement using the direct contact method. However, if we use a columnar rod between an ultrasonic probe and a target object, we can measure without the transmission pulse. This paper describes the measurement system of the object thickness by the rod and fuzzy logic. The evaluation method consists of three stages. First, the surface echo position is determined from the acquisition ultrasonic wave. Second, the bottom echo position is decided by using fuzzy inference. Finally, the object thickness is calculated from the surface position and the bottom position. We applied our method to ten materials with different thickness. As the result, our method was able to evaluate the thickness of all materials within the error rate of 6.0%