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Unread 01-02-2008, 09:04
Steve_Alaniz Steve_Alaniz is offline
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Re: Encoders 3-6 Trouble

Quote:
Originally Posted by Qbranch View Post
Just a question... are you doing velocity control? If so, I'm guessing you're running in the 39.37Hz (25.4ms) loop? Is this enough resolution?

By my calculations, you can have an absolute maximum velocity control resolution of 0.39ft/sec. Is your robot really really fast? Hence the low res encoder?

-q

I'm using the encoders for distance in autonomous mode. The robot is capable of about 8ft/sec at the very top speed. I've run it on short full speed but haven't written the PID coding yet, so I don't know the accuracy just yet, but the simple number tweaking I've done looks promising so I'm expecting really good results from the PID. I'm reading a 6" wheel which in theory gives me a resolution of 6*PI/128 about .15 inch/ count. That's probably more than I need and I hope to have the PID tested and tuned by Monday, I hope.

Steve