# Hybrid Fault Diagnosis of Bearings: Adaptive Fuzzy Orthonormal-ARX Robust Feedback Observer
## 3 Anomaly Diagnosis Based on Proposed Hybrid Algorithm
### Fault Detection and Fault Classification
Furthermore, the average of single-type fault diagnosis accuracy in the presence of load variation for the proposed method is about 97.5%, for the SFO is about 90.3%, and for the FO is 86%. Additionally, for multi-type faults, the average of diagnostic accuracy in the presence of motor speed variation for the proposed method, SFO, and FO are 97.95%, 94.9%, and 80.35%, respectively. In future work, the prognostics challenge will be solved using hybrid observation approaches. All of the authors contributed equally to the conception of the idea, the design of experiments, the analysis and interpretation of results, as well as the writing of the manuscript. Writing--original draft preparation, F.P. and J.-M.K. ; writing--review and editing, F.P. and J.-M.K. All authors have read and agreed to the published version of the manuscript. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Algorithms** & **PM (Proposed Method)** & **SFO** & **FO** \\ \hline
**Crack Diameters (mm)** & 3 & 6 & 3 & 6 & 3 & 6 \\
**Normal** & 100\% & 100\% & 100\% & 100\% & 89\% & 89\% \\
**IR Fault** & 98\% & 98\% & 92\% & 94\% & 80\% & 80\% \\
**OR Fault** & 99\% & 98\% & 92\% & 94\% & 76\% & 78\% \\
**Ball Fault** & 97\% & 98\% & 94\% & 94\% & 76\% & 79\% \\
**IR-Ball Fault** & 97\% & 97\% & 94\% & 94\% & 76\% & 77\% \\
**OR-Ball Fault** & 97\% & 97\% & 95\% & 95\% & 80\% & 80\% \\
**IR-OR Fault** & 97\% & 98\% & 94\% & 95\% & 81\% & 81\% \\
**IR-OR-Ball Fault** & 98\% & 98\% & 95\% & 96\% & 81\% & 82\% \\ \hline
**ACA\%** & 97.9 & 98 & 94.5 & 95.3 & 79.9 & 80.8 \\ \hline \hline \end{tabular}
\end{table} 
Table 12: The multi-fault diagnosis accuracy for motor speed-variant dataset. **Funding:** This research was financially supported by the Ministry of Trade, Industry & Energy(MOTIE) of the Republic of Korea and Korea Institute for Advancement of Technology(KIAT) through the Encouragement Program for The Industries of Economic Cooperation Region. (P0006123). **Conflicts of Interest:** The authors have no conflicts of interest to declare. ## References

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