Reliability modeling and life estimation using an expectation maximization based wiener degradation model for...

Area of Science:

• Aerospace Engineering
• Reliability Engineering
• Statistical Modeling

Background:

• Momentum wheels (MW) are critical components for satellite mission success.
• Degradation data from performance characteristics is essential for assessing MW reliability.
• Existing models may not fully capture the complex degradation patterns of MW.

Purpose of the Study:

• To develop a novel reliability modeling and life estimation approach for satellite MW.
• To utilize a Wiener degradation model combined with the expectation maximization (EM) algorithm.
• To provide accurate life predictions for MW based on observed degradation.

Main Methods:

• Established a Wiener degradation model incorporating random effects, informed by failure modes, mechanisms, and effects analysis.
• Employed the first hitting time concept to define and model failure time.
• Utilized the expectation maximization (EM) algorithm to efficiently estimate model parameters from latent variables in the likelihood function.

Main Results:

• Derived an explicit reliability function based on the Wiener degradation model.
• Successfully estimated model parameters using the EM algorithm, handling unobserved latent variables.
• Validated the developed approach using real-world degradation data from a specific type of MW.

Conclusions:

• The proposed approach provides an effective method for reliability modeling and life estimation of satellite MW.
• The integration of Wiener process and EM algorithm offers a robust framework for analyzing component degradation.
• This methodology enhances the prediction of MW lifespan, contributing to improved satellite mission assurance.