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Extract RPM signal from tachometer pulses

`rpm = tachorpm(x,fs)`

```
[rpm,t,tp]
= tachorpm(x,fs)
```

`[___] = tachorpm(x,fs,Name,Value)`

`tachorpm(___)`

`[___] = tachorpm(`

specifies
options using `x`

,`fs`

,`Name,Value`

)`Name,Value`

pairs and any of the
previous syntaxes.

`tachorpm(___)`

with no output
arguments plots the generated RPM signal and the tachometer signal
with the detected pulses.

The `tachorpm`

function performs these steps:

Uses

`statelevels`

to determine the low and high states of the tachometer signal.Uses

`risetime`

and`falltime`

to find the times at which each pulse starts and ends. It then averages these readings to locate the time of each pulse.Uses

`diff`

to determine the time intervals between pulse centers and computes the RPM values at the interval midpoints using RPM = 60 / Δ*t*.If

`'FitType'`

is specified as`'smooth'`

, then the function performs least-squares fitting using splines. If`'FitType'`

is specified as`'linear'`

, then the function performs linear interpolation using`interp1`

.

[1] Brandt, Anders. *Noise and Vibration Analysis:
Signal Analysis and Experimental Procedures*. Chichester,
UK: John Wiley & Sons, 2011.

[2] Vold, Håvard, and Jan Leuridan. “High Resolution
Order Tracking at Extreme Slew Rates Using Kalman Tracking Filters.” *Shock
and Vibration*. Vol. 2, 1995, pp. 507–515.

`orderspectrum`

| `ordertrack`

| `orderwaveform`

| `rpmfreqmap`

| `rpmordermap`

| `statelevels`

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