Research on Metal Magnetic Memory Signal Singularity Detection

Two novel signal singularity detection (SSD) algorithms for metal magnetic memory (MMM) signal are put forward in this paper: the signal segmented fluctuation and the signal segmented dissimilarity. What the former results from is that the MMM signal corresponding to the stress concentrated area (SCA) fluctuates more heavily than non SCA while the latter is based on the fact that if the MMM signal, which has a definite length, is segmented in a certain interval, the stress concentrated segments (SCS) are generally far less than those which are not stress concentrated by number, and the signals of the non SCSs are similar to each other, but the signals from SCSs are dissimilar to those of non SCSs. The two methods have the advantage in the detection of the metallic work piece which is non defective in looks but fatigued as well as may be helpful to detect the singularity of the signals such as negative pressure wave, ultrasonic wave etc. Experimental result with real data demonstrates the effectiveness of the proposed algorithms. Moreover, the MMM SSD software implementation are considered.