Ball Screw Fault Detection and Location Based on Outlier and Instantaneous Rotational Frequency Estimation

Figure 11

The results of the instantaneous rotational frequency estimation: (a) the time-frequency distribution of experiment 1; (b) the detailed time-frequency distribution of experiment 1; (c) the instantaneous rotational frequency of experiment 1; (d) the time-frequency distribution of experiment 2; (e) the detailed time-frequency distribution of experiment 2; (f) the instantaneous rotational frequency of experiment 2.

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