How do I start collecting data after I've reached a target velocity?

[BEBUofI]

I am new to LabView and I am trying to collect data on the coefficient of sliding friction.  I want the DAQ Assistant to start collecting data after the test skid has reached its target maximum velocity.  I can't find any bit or flag that would work as this trigger and I am having a hard time reading and finding the info from my encoder. 
Any bright ideas??
thanks
-beb

[johnsold]

Any reason why you cannot start the data collection when the skid begins moving and throw away the data that comes in before the target is reached?

Lynn

[BEBUofI]

I suppose so, if I have to.  I am still having problems finding a target velocity flag

[johnsold]

How are you measuring the velocity? That may have a significant influence on how to detect the desired point. How long does the acceleration last compared to the constant velocity section? What is your sampling rate and how many channels?

The more information we have about your setup,the more likely someone will be able to help you to a goood solution.

Lynn

[Otis]

Honestly, you will probably need to read the data the entire time, and then in software determine that if the rate is increasing then you don't want to log to disk.  As soon as the rate begins decreasing though you will want to begin logging to disk.

You will have to give us much more information such as how you are reading the velocity, how long the tests are, and how many channels of what types of data you are trying to analyze.

[BEBUofI]

Yea, I will give you as much information as I can, but not over the weekend. 
I'll post again probably Monday.