Systematic Fatigue Test Spectrum Editing Using Wavelet Transformations

Our Phase I effort showed that spectrum compression could be successfully achieved via Wavelet Transform (WT) based Fatigue Spectrum Editing (FSE) techniques for uniaxial HCF spectra cases. For example, 85% reduction in spectrum length can be achieved in the case of the original FELIX spectrum. However, the extension of the same FSE technique to multi-axial HCF cases showed less desirable results as we could only attain up to 50% reduction of the original spectrum in the example cases we investigated. To achieve higher spectrum compression levels cases in multiaxial HCF cases as well as for uniaxial HFC+LCF cases involving load interaction effects, we therefore propose further enhancement and development efforts in the following areas: algorithm enhancements to cover LCF and HCF cases, experimental effort for verification and validation, and improve computational efficiency through a distributed computational framework. The above proposed research effort will also support in the completion of our envisioned framework that has the signal generation and preprocessing module, signal processing module, damage calculation module, optimization module and validation experiments to achieve the desired FSE performances. Ultimately, this research effort will provide certification of FSE techniques in spectrum editing techniques for most applications.