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

Figure 12

The results of the instantaneous rotational frequency estimation based on continuous wavelet transform: (a) the detailed time-frequency distribution of experiment 1; (b) the instantaneous rotational frequency of experiment 1; (c) the detailed time-frequency distribution of experiment 2; (d) the instantaneous rotational frequency of experiment 2.

(a)

(b)

(c)

(d)