Material characterization of thin planar structures using full-field harmonic vibration response measured with...

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Physics

Background:

• Accurate material characterization is crucial for designing thin 2-D structures.
• Traditional methods may struggle with noisy or limited vibration data.
• Non-contact measurement techniques like holography offer potential for advanced analysis.

Purpose of the Study:

• To develop a novel, robust method for estimating the Young's modulus of thin 2-D structures.
• To utilize non-modal, single-frequency harmonic vibration data measured via holography.
• To assess the method's accuracy and robustness in the presence of noise and parameter uncertainties.

Main Methods:

• Finite-difference discretization of the plate equation applied to holographic displacement data.
• Bayesian optimization to minimize the difference between measured and calculated displacement fields.
• Validation using analytical solutions and finite-element method (FEM) simulations with added noise.

Main Results:

• The proposed method accurately estimates Young's modulus with errors below 5%, even at signal-to-noise ratios as low as 0 dB.
• Quantified the impact of uncertainties in geometric, material, and boundary parameters on modulus estimation.
• Demonstrated the method's applicability to experimental holographic data from a copper plate.

Conclusions:

• The novel Bayesian optimization approach provides a reliable method for material characterization of thin 2-D structures from noisy vibration data.
• The technique is robust to noise and parameter uncertainties, making it suitable for experimental applications.
• This method advances non-destructive material property evaluation using optical measurement techniques.