[Ether]

http://vamfun.wordpress.com/2012/02/...city-pid-loop/

"Apply a normal PID loop with speed as the input, set the D term to zero and have a high integration gain , KI, that responds quickly to the error and holds the speed reference when the error goes to zero. The integrator must have full authority in this case. KP is adjusted to add damping and minimize the overshoot. This is the method I recommend and was the basis for the last post on precomputing PID gains."

Caveat:
The following is an excerpt from a post dated 01-14-2012 in the thread titled 2012: Tuning the Jaguar's Speed Control PID Loop :

Originally Posted by Mr. Lim

The I-term appears to be capped. Theoretically, even a small I-term should cause the speed control loop to reach its setpoint eventually. It might take a long time, but it should reach the setpoint, given enough time.

It does not.

What we're seeing is the maximum speed we can achieve is directly proportional to the I constant.

This is unfortunate, because we have been able to find some I-constants which appear to work beautifully, however since the I-term is capped, we can never quite achieve our top speed.

Capping the I-term is usually a great way to ensure our PIDs don't wind up too much, however in this case, it's inhibiting us from ever getting to our top speed.