*Article* **AOC-OPTICS: Automatic Online Classification for Condition Monitoring of Rolling Bearing**

**Hassane Hotait 1, Xavier Chiementin 1,\* and Lanto Rasolofondraibe 2,\***


 CReSTIC, University of Reims Champagne Ardenne, Moulin de la Housse, 51687 Reims Cedex 2, France**\***Correspondence:xavier.chiementin@univ-reims.fr (X.C.);lanto.rasolofondraibe@univ-reims.fr(L.R.)

Received:3April2020;Accepted:15May 2020;Published:20May2020

**Abstract:** Bearings are essential components in rotating machines. They ensure the rotation and power transmission. So, these components are essential elements for industrial machines. Thus, real-time monitoring is required to detect a possible anomaly, diagnose the failure of rolling bearing and follow its evolution. This paper presents a methodology for automatic online implementation of fault diagnosis of rolling bearings, by AOC-OPTICS (automatic online classification monitoring based on ordering points to identify clustering structure, OPTICS). The algorithm consists of three phases namely: initialization, detection and follow-up. These phases use the combination of features extraction methods, smart ranking, features weighting and classification by the OPTICS method. Two methods have been integrated in the dimension reduction step to improve the efficiency of detection and the followed of the defect (relief method and t-distributed stochastic neighbor embedding method). Thus, the determination of the internal parameters of the OPTICS method is improved. A regression model and exponential model are used to track the fault. The analytical simulations discuss the influence of parameters automation. Experimental validation shows detection with 100% accuracy and regression models of monitoring reaching *R*<sup>2</sup> = 0.992.

**Keywords:** rolling bearing; condition monitoring; classification; OPTICS
