Feature category | Abbreviation | Features | No. Tri-axial features | No. Magnitude features |
---|---|---|---|---|
Time | T | Root mean square, range, mean, variance, skew, kurtosis | 18 | 6 |
Frequency | F | Dominant frequency, Relative magnitude, Moments of power spectral density (mean, standard deviation, skew, kurtosis) | 18 | 6 |
Entropy | E | Sample entropy | 3 | 1 |
Correlation | C | Cross-correlation peak (XY,XZ,YZ), Cross-correlation lag (XY,XZ,YZ) | 6 | 0 |
Derivative | D | Moments of the signal derivative (mean, standard deviation, skew, kurtosis) | 12 | 4 |
Total for each sensor type | 57 | 17 |