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Unread 27-01-2013, 23:24
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Re: Set the rate of acceleration

Quote:
Originally Posted by BPtigers View Post
I believe I found the pid thing, but I'm not sure which one it is, or how to hook it up to what?
You want the PID Output Rate Limiter.vi (it's the bottom one of the three in your image). As with any LabVIEW function, its inputs and outputs are described in the popup help. The only inputs you need to be concerned with are "input" and "output rate", and the output is called "output".

Just insert it on the wire where you want to limit the rate of change of a value, with the source connected to "input", the destination connected to "output", and a number representing the maximum rate of change connected to "output rate". You can use a front-panel control as the source of the rate number, so you can change it while the program is running. Just remember to either replace it with a constant or "make current value default" when you determine the rate you want.

Quote:
Also I have no idea what your talking about the 100 to the 1000 thing where is that? I am newbie Sorry for any frustrations, Thanks
The output rate is in units of "EGU per minute". Since you probably want to limit the motor rate of change to go from full scale reverse to full scale forward in about a half second (give or take an factor of two or so), that's something like 4 per second, which is 240 per minute. Start there and tweak it up or down until you get a value that works for you.
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