At present, the magnetic tile defects are mainly detected by manual work, which is of low efficiency and precision, requiring strong intensity of labor. At the same time, missing and false detection frequently happen. An automatic detection system with low cost and high reliability is required.
The method proposed in this paper is basically a NDT one. There are many NDT methods for ferrite magnetic titles: eddy current testing [1] and [2], ultrasonic testing [3], magnetic particle testing [4] and [5], penetrant testing [6], etc. The eddy current and ultrasonic testing are usually more suitable for large-size plates. In magnetic particle and penetrant testing, the process is more complex than machine vision systems in magnetic tile defects detection