[NotInControl]

Originally Posted by techhelpbb

Re: NotInControl

I couldn't find anyone that made this work in competition last year...and this is probably the reason why:

http://www.chiefdelphi.com/forums/sh...t=89697&page=3

So as a participant in those prior conversations I'll tell you what I found:

The encoders do not split nicely like that. I encourage you to look at the produced output signal when you are doing so using an oscilloscope.

There is a chance you can get them to work regardless of the issues it creates but I suspect the system noise will occasionally get the better of you. I will not speculate on how often, but from what I've seen using wiring well within the standards of inspection for U.S. FIRST (and load tested beyond the standards)...often enough you might consider it an issue...especially in systems with many loaded CIMs.

Thanks for the info. I figured it wouldn't be as easy as splitting the encoder signals. But like I said I know there are solutions available, but at a risk. I'd rather be done with it on the CRIO than debugging the problem through the last week of build on the Jag.

As for the method I use to determine the gains:
I prefer the more modern approach of simulating the plant and designing a controller to a model and then implementing in on the real system and tweaking from there. I create a plant model in matlab or simulink and use the control system toolbox to determine the gains (within a close range because my model is a linear approximation of the system and doesn't account for all physical effects of the system.)

Guess and check methods like Ziegler-Nicholos methods do work but I feel that Guess and Check methods only work if you really have a background in control systems or have enough experience with controllers to know exactly how to react when you see certain behavior. I'd always recommend the modern approach, because at a minimum it will give you a starting point for your gains, where you can then tweak by hand. I'll always recommend the simulation approach over guess and check.

The gains for my test on the Jag were using the same process I documented in the video I posted earlier.


Regards,
Kevin