Degradation Stage Division Method of Coordinate System Angle Based on New Health Index

A new method for constructing health index and dividing bearing degradation stages is proposed to address the problem that the traditional comprehensive evaluation index of rolling bearings cannot describe the cumulative degradation process of bearings and the difficulty in dividing degradation stages. Firstly, based on the time domain features peak value, the cumulative sum of peak values is calculated as the health index, which can explain the cumulative degradation process of the bearing from a physical perspective. Then, according to the operating characteristics of the bearing, the angle between the bearing health index and the x-axis positive direction of the coordinate system is obtained to form an angle data set. Finally, each point in the angle data set is traversed to find the points that meet the given conditions in the included Angle data set. This point is taken as the degradation point to divide the operating stages of the bearing. The experimental results show that the proposed method has generalization ability and the divided stages.