OAT Convert to Even Angle Signal VI

OAT Convert to Even Angle Signal VI

Owning Palette: Order Analysis VIs

Requires: Sound and Vibration Toolkit

Converts an even-time-spaced scaled signal to an even-angle-spaced signal by resampling the acquired signal. Wire data to the scaled signal [EU] input to determine the polymorphic instance to use or manually select the instance.

Minimum Data Requirements
This function requires a minimum amount of signal and speed profile data before an output will be returned. reset?, analysis method, pulse/revolution, max order, and zero delay? will affect the amount of data required before an output is returned.

Note  Choosing a large max order is computationally intense, resulting in slower processing times and increased memory usage.

Details  

OAT Convert to Even Angle Signal (1 Ch)

	reset? specifies the initialization of the internal states. The first time this VI runs, or when reset? is TRUE, the internal states initialize to zero. If reset? is FALSE, this VI sets the internal states to the final states from the previous call to the VI. The default is FALSE.
	analysis method specifies the analysis method this VI uses to convert the scaled signal [EU] to even-angle signal. 0 fast (default)—The fast method can generate accurate results suitable for most applications and works well with both analog and digital tachometer signals. 1 accurate—The accurate method can generate more accurate results than the fast method, especially if you are performing run-up or run-down tests with high speed transition rates. However, the accurate method requires an accurate tachometer pulse measurement to generate accurate results. Typically, using a counter to acquire digital tachometer signals yields an accurate tachometer pulse position. This method also is approximately 30% slower than the fast method.
	scaled signal [EU] specifies the scaled signal expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define a virtual channel in National Instruments Measurement & Automation Explorer (MAX). t0 specifies the start time of the waveform. dt specifies the time interval in seconds between data points in the waveform. Y specifies the data values of the waveform.
	speed profile specifies the tachometer-pulse arrival time and the rotational speed at each pulse. time [s] specifies the time instant of pulses in seconds. speed [RPM] specifies the rotational speed at each pulse time instant in revolutions per minute.
	pulse/revolution specifies the number of pulses the tachometer generates during each revolution. The default is 1.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	max order specifies the maximum order to analyze. If the value of this parameter is less than or equal to zero, this VI automatically sets the maximum order to analyze. The maximum order used might be larger than the one you specify. Review actual max order entry for calculation. The default is 0 (auto).
	zero delay? specifies whether a filter delay exists between the input signal and the output signal. The default is FALSE.
	even-angle signal returns data resampled at even-angle intervals. This parameter is synchronous to the rotational speed with constant number of samples per revolution. r0 returns the starting index value for counting revolutions. dr returns the revolution interval between two sequential samples. Y returns the values of even-angle spaced samples in a scaled engineering unit.
	even-angle channel info returns information that you can pass to another VI about the measurement configuration for even-angle signal. Note  You must wire even-angle channel info when performing extended measurements. Do not modify the even-angle channel info values. If you want to view the information, you can create a custom probe.
	even-angle position info returns the position information of even-angle signals. positions [s] returns the locations of the samples in seconds. samples/rev returns the number of samples per revolution.
	error out contains error information. This output provides standard error out functionality.
	actual max order is the actual measured maximum order this VI uses. actual max order is calculated using max order and pulse/revolution:

OAT Convert to Even Angle Signal (N Ch)

	reset? specifies the initialization of the internal states. The first time this VI runs, or when reset? is TRUE, the internal states initialize to zero. If reset? is FALSE, this VI sets the internal states to the final states from the previous call to the VI. The default is FALSE.
	analysis method specifies the analysis method this VI uses to convert the scaled signal [EU] to even-angle signal. 0 fast (default)—The fast method can generate accurate results suitable for most applications and works well with both analog and digital tachometer signals. 1 accurate—The accurate method can generate more accurate results than the fast method, especially if you are performing run-up or run-down tests with high speed transition rates. However, the accurate method requires an accurate tachometer pulse measurement to generate accurate results. Typically, using a counter to acquire digital tachometer signals yields an accurate tachometer pulse position. This method also is approximately 30% slower than the fast method.
	scaled signals specifies the scaled signals expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define a virtual channel in National Instruments Measurement & Automation Explorer (MAX). t0 specifies the start time of the waveform. dt specifies the time interval in seconds between data points in the waveform. Y specifies the data values of the waveform.
	speed profile specifies the tachometer-pulse arrival time and the rotational speed at each pulse. time [s] specifies the time instant of pulses in seconds. speed [RPM] specifies the rotational speed at each pulse time instant in revolutions per minute.
	pulse/revolution specifies the number of pulses the tachometer generates during each revolution. The default is 1.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	max order specifies the maximum order to analyze. If the value of this parameter is less than or equal to zero, this VI automatically sets the maximum order to analyze. The maximum order used might be larger than the one you specify. Review actual max order entry for calculation. The default is 0 (auto).
	zero delay? specifies whether a filter delay exists between the input signal and the output signal. The default is FALSE.
	even-angle signals returns the data resampled at even-angle intervals for each channel. even-angle signals are synchronous to the rotational speed with constant number of samples per revolution. r0 returns the starting index value for counting revolutions. dr returns the revolution interval between two sequential samples. Y returns the values of even-angle spaced samples in a scaled engineering unit.
	even-angle channel info returns information that you can pass to another VI about the measurement configuration for even-angle signal. Note  You must wire even-angle channel info when performing extended measurements. Do not modify the even-angle channel info values. If you want to view the information, you can create a custom probe.
	even-angle position info returns the position information of even-angle signals. positions [s] returns the locations of the samples in seconds. samples/rev returns the number of samples per revolution.
	error out contains error information. This output provides standard error out functionality.
	actual max order is the actual measured maximum order this VI uses. actual max order is calculated using max order and pulse/revolution:

OAT Convert to Even Angle Signal Details

The output signal is synchronous to the rotational speed with a constant number of samples per revolution.

Use the SVPO Convert to Even Angle Signal VI to convert an even-time-spaced scaled signal to an even-angle-spaced signal on embedded targets that have limited computational resources.