Damage Delay Factor for Composite Laminate Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current structural health monitoring methods for composite laminates face challenges in accurate and stable damage detection due to limitations in probabilistic diagnostic imaging and delay and sum methods, including restricted imaging capability, high costs, and artifacts in reconstructed images.
Innovation Solution
A probability multiply-sum structural damage imaging positioning method and system based on a delay factor, which uses a damage delay factor in path probability distribution functions to improve damage positioning accuracy and robustness, incorporating optimal excitation frequency, group-velocity correction, and path probability multiply-sum operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the probabilistic diagnostic imaging method is used, then damage probability of path or path intersection is strengthened, but imaging capability is restricted and non-path damage positioning is inconvenient
Solution Approach 1:
The patent combines the probabilistic diagnostic imaging method with the delay and sum method to create a multiply-sum imaging approach. This merging integrates the strength of path probability strengthening with the capability of accurate damage positioning, allowing the system to handle both path and non-path damage effectively while maintaining imaging quality without requiring denser sensor networks.
2Measurement precision
If a denser sensor network is used to cover more damaged regions, then imaging quality is improved, but costs increase
Solution Approach 1:
The patent makes the sensor network sparse yet effective by designing a sensor arrangement that can detect various types of damage (path damage, non-path damage, off-axis damage) using a limited number of sensors. The multiply-sum algorithm enables each sensor to contribute to multiple detection functions, eliminating the need for a denser sensor network while maintaining comprehensive monitoring coverage and imaging quality.
3Measurement precision
If the delay and sum method is used, then accurate imaging and quick detection of large-area structures are achieved, but artifacts appear in reconstructed images due to unknown modulus parameters and theoretical approximation errors
Solution Approach 1:
The patent introduces a damage delay factor as an intermediary parameter that bridges the gap between theoretical group velocity and actual measured group velocity. This delay factor acts as a correction mechanism that accounts for material property variations and theoretical approximation errors, enabling accurate damage positioning while eliminating artifacts in the reconstructed images by reconciling theoretical models with actual measurements.
4Measurement precision
If algorithm tolerance or denoising design is used, then accurate positioning is achieved, but the method depends on prior knowledge such as dispersion and group velocity
Solution Approach 1:
The patent implements a feedback mechanism where the damage delay factor is calculated from actual measured group velocity data and used to correct theoretical predictions. This feedback loop continuously adjusts the imaging algorithm based on real measurements, reducing dependence on prior knowledge about material properties while maintaining high positioning accuracy. The system adapts to actual material behavior rather than relying solely on pre-established theoretical values.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enhances damage detection accuracy and robustness by reducing artifacts and improving off-axis positioning, leading to more reliable structural health monitoring and reduced maintenance costs.
Implementation Method 1
ultrasonic guided waves are excited and captured through proper design of a piezoelectric sensor network
Implementation Method 2
ultrasonic guided waves are used as a bearing and transmission medium of damage information
Data Source
AI summary
A probability multiply-sum structural damage imaging positioning method and system based on a delay factor includes obtaining optimal excitation frequency and group-velocity theoretical correction function based on numerical simulation of composite laminates; based on optimal excitation frequency, obtaining ultrasonic guided wave response signals of composite laminates in healthy and lossy states and sensor coordinates used for signal collection; performing path screening based on ultrasonic guided wave response signals; obtaining group-velocity correction function based on measured group velocity obtained based on ultrasonic guided wave response signal in healthy state, and calculating actual delay time based on obtained effective path, group-velocity correction function, and sensor coordinates; obtaining damage delay factor based on actual and reference delay time; forming path probability distribution based on damage delay factor, and performing path probability multiply-sum operation to obtain structural damage imaging result; and obtaining structural damage positioning result based on peak point coordinates of imaging result.