A Method for Separating Echo Signals for Ultrasonic Flaw Detection

Abstract

The invention discloses a method for separating echo signals for ultrasonic flaw detection, comprising steps: 1. Acquisition and synchronous upload of ultrasonic echo signals: using an ultrasonic flaw detection device to perform ultrasonic detection on a measured object to obtain ultrasonic echo signals of the measured object F(t), and the obtained ultrasonic echo signal F(t) is synchronously transmitted to the data processing device; the ultrasonic echo signal F(t) includes ultrasonic echoes at the positions of K defects in the measured object signal; 2. signal sparse decomposition; 3. echo signal separation: using data processing equipment and according to the iterative decomposition of the K best matching atoms in the optimal atom set at this time, the ultrasonic echo signal F(t) is Separation to obtain K separation signals. The method of the invention has simple steps, reasonable design, convenient implementation and good use effect, and realizes simple and fast separation of superimposed signals at the positions of multiple defects in the same ultrasonic echo signal by using signal sparse decomposition.

Description

Technical field [0001] The present invention belongs to the field of ultrasonic flaw detection, and more particularly to an echo signal separation method for ultrasonic flaw detection. Background technique [0002] Ultrasonic flaw detection (also known as ultrasound detection or ultrasonic detection) is a non-destructive detection method for detecting the internal defects of the material and the energy variation of the ultrasonic propagation waveform reflection and transmission time using the material and its defect. The principle of ultrasonic flaw is that ultrasonic waves have a small transmission loss in the solid, and the detection depth is large. Due to the phenomenon of reflection and reflection in the heterogeneous interface, it is not possible to pass the gas solid interface, if there is a gas hole, crack, Defects such as layered (gas in defects) or inclusions, ultrasonic (also known as ultrasonic signals or ultrasound signals) are propagated to the interface of metal and...

AI Technical Summary

Problems solved by technology

[0008] In addition, when using the sparse decomposition method for signal denoising (also called signal extraction), the essence is to use the matching pursuit algorithm for signal extraction. Because in the matching pursuit algorithm, firstly, the selection of Gabor atoms has no physical meaning, and secondly, if If a wrong Gabor atom is selected in a certain iteration, the subsequent iteration process has to correct this error, resulting in mistracking and poor algorithm performance.

Moreover, according to the sparse signal representation theory, when the size of dictionary atoms is smaller than a threshold, due to the cumulative consistency constraints, the sparse representation is unstable and unreliable

Therefore, the existing sparse decomposition methods have many defects

Images