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Unread 04-02-2017, 18:24
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Re: We are trying to set up PID

P is proportional gain. That gain pushes back based on how far off you are. I is integral gain. It pushes back based on how long you've been how far away. Finally, D is derivative gain. It pushes back based on how fast you're going away.

In LabVIEW, it works a little weird, as you'll notice you have proportional gain, integral "time" and derivative "time." The way this works is that when you increase the P gain, all three gains are actually being increased, and the "time" values are multiplied by the P values to get their respective gain values (in a very weird way, there are extra multipliers in there, so don't go trying to figure out what your gains are, just roll with it)

You have to tune PID loops no matter what, it takes time, it's slightly dangerous (integral gain can run away from you fast, so have your hand on the E-stop), and honestly it's far from easy.

Good luck!
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