Ultrasound Defect Localization in Shell Structures with Lamb Waves Using Spare Sensor Array and Orthogonal Matching...

Area of Science:

• Structural Health Monitoring
• Wave Propagation Analysis
• Non-Destructive Testing

Background:

• Lamb wave-based Structural Health Monitoring (SHM) faces challenges in damage localization due to multimodal and dispersion effects, limiting resolution.
• Existing methods often require numerous sensors, increasing complexity and cost.
• High-resolution damage detection with minimal sensor deployment is crucial for practical SHM applications.

Purpose of the Study:

• To propose and validate a novel method for high-resolution Lamb wave damage localization using a minimal number of sensors.
• To develop an Orthogonal Matching Pursuit (OMP)-based algorithm for effective separation of wave packets and dispersion removal.
• To demonstrate the feasibility of using only two piezoelectric transducers for accurate defect detection.

Main Methods:

• Development of an Orthogonal Matching Pursuit (OMP)-based decomposition and dispersion removal algorithm.
• Algorithm application to separate wave packets corresponding to different propagation paths and remove dispersion effects.
• Verification using simulation signals with both non-overlapped and overlapped wave packets.

Main Results:

• The proposed OMP-based algorithm successfully separated wave packets reflected from simulated defects and structural edges.
• The method demonstrated effective dispersion removal, enabling clearer signal analysis.
• Damage localization was achieved with a sparse sensor array comprising only two piezoelectric transducers.

Conclusions:

• The Orthogonal Matching Pursuit (OMP)-based algorithm significantly enhances the resolution of Lamb wave-based damage localization.
• The proposed method allows for defect detection using a minimal sensor configuration (two transducers), reducing system complexity.
• This approach offers a promising solution for efficient and high-resolution Structural Health Monitoring.