Controlling a strobe to automatically capture rotational speed

This is pretty far out there but I figured, if I don't ask, I'll never know if somone has thought about it.
We use an LED strobe to measure rotational spped of a product during testing. Basically, the strobe pulse rate is adjusted until it matches the RPM's of the rotation and due to the effect, the rotation appears [relatively] stationary.
The particular strobe device I am using has some input/output control, for instance, I know I can read the rate on the output and I think I may be able to control the rate on the input.
Assuming I can control the rate, the big question is, are there any [somewhat simple] methods anyone knows of that would allow me to determine when the strobe rate matches the rotational speed of my product. I would think it would require some type of camera setup that monitors the area of rotation and can automatically 'see' when the apparent rotation 'due to strobe effect' effectively stops.
Don't think I will have a lot of time on current project to implement this (unless it really IS simple) but am wanting to plan for next level and make sure I start feeding the seeds for buy-in down the road.
Any thoughts appreciated
Doug
Doug
"My only wish is that I am capable of learning each and every day until my last breath."

No mounting? Hmm. If the rotational part has "features" (I.E., grooves or parts that stick out) you might be able to use a reflective sensor. Same idea as a rotary encoder but the light is directed to the part itself and as features pass by you can read the variations in light intensity. Highly dependant on any features being present and material type. I will continue to think about it...

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Thansk for your reply. You are right that measure frequency to get the speed is the best way, but it's hard to get the dirction at the same time. You suggest me that "perform two angle measurements to get the sense of rotation", but I'm not sure I catched what you mean about this. I try to understand your opinion like this: distribute the signals to 2 counters, and start 2 tasks, one for frequency, the other for angle which used for deciding the dirction?
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RobertoBozzolo 已写：
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http://www.ni.com/ask
Make our forums great:
If you like the answer, don't forget to "Kudos!".
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Controlling a strobe to automatically capture rotational speed

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