The rms level is a simple magnitude of the signal in the time domain and frequency domain. Figure
A1 displays the measured torque in the system and the rms level of accelerometer number 1, with
the fourteen selected records marked on the plots with stars. Moderate increases occur in the rms
level at records 240, 390 and 420. A large increase occurs in rms around record 440 and maximum
occurs at 443. The rms amplitudes of the time-frequency transforms of the data (fig. A2 and A3)
follow a different trend. The amplitudes of most of the time-frequency transforms decrease at each
torque increase with the following exceptions: negligible decrease for the WV-CW transform at the
125% to 150% (records 209, 210) torque increase; small amplitude increase for the CWT at the 80%
to 100% (records 43, 44) torque increase; and negligible decrease for the CWT at the 125% to 150%
torque increase. Table A1 lists all of these magnitudes for the fourteen selected data records.