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A degradation feature extraction technique based on static divided symbol sequence entropy
Chunxia Gu1, Juan Bi2, Bing Wang3
1School of Economics & Management, Shanghai Maritime University, Shanghai, China.
A new static divided symbol sequence entropy method accurately extracts degradation features from quay crane gearbox vibration signals. This technique enhances complexity characterization and sensitively describes performance degradation, offering a fast foundation for health evaluations.
Area of Science:
- Mechanical Engineering
- Signal Processing
- Condition Monitoring
Background:
- Traditional methods struggle to identify degradation patterns in quay crane gearbox vibration signals due to noise and impact components.
- Accurate feature extraction is crucial for effective condition monitoring and predictive maintenance of critical machinery.
Purpose of the Study:
- To propose a novel degradation feature extraction technique for quay crane gearbox vibration signals.
- To enhance the characterization of signal complexity and performance degradation in the presence of noise.
Main Methods:
- Development of a static divided symbol sequence entropy technique based on basic scale entropy.
- Uniform symbolization standard using the root mean square of the health condition signal and a scale coefficient.
- Expansion of the symbol set to improve information content and complexity characterization, especially in large-value regions.
Main Results:
- The proposed technique accurately and flexibly characterizes performance degradations in vibration signals.
- Analysis using logistic chaotic sequences and hoisting mechanism gearbox lifetime signals demonstrates sensitive description of performance degradation.
- The method effectively characterizes the complexity of nonlinear time series.
Conclusions:
- The static divided symbol sequence entropy technique offers a robust solution for extracting degradation features from noisy vibration data.
- The method is computationally fast and suitable for real-time applications.
- This technique provides a foundation for developing advanced health evaluation methods for quay crane gearboxes.
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