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Some test environments do not allow you to install a tachometer onto the device under test (DUT) to obtain a speed reference. Use the OAT Tachless Speed Profile Generator VI to compute a simulated speed profile from the sound or vibration signal spectral map when you cannot install a tachometer onto the DUT. A window with a time-frequency colormap appears every time you run the OAT Tachless Speed Profile Generator VI. You must specify the order components on the colormap to generate the simulated speed profile.

Refer to the Tachless Order Tracking (Offline) VI in the labview\examples\Order Analysis\Tachless Order Tracking directory for an example of generating a simulated speed profile.

Note  You cannot use a simulated speed profile with resampling-based order analysis VIs such as the OAT Convert to Even Angle Signal VI and the OAT Spectral Map VI. The simulated speed profile works only with order analysis VIs based on the Gabor transform, such as the OAT Extract Order Waveform VI and the OAT Extract Most Significant Order Waveforms VI.

Use a simulated speed profile to extract order waveforms and compute the order magnitude from those order waveforms. Because of the lack of a real tachometer trigger signal, you cannot obtain accurate phase information with a simulated speed profile.