In terms of espresso technology, a simplified definition of PID = an electronic brew temperature controller. There's tons of information on p
erivative controls (PID). Below are a few introductions:
- What is PID - short and sweet, not overly technical.
- PID controller - Wikipedia's definition. More technical, a little more on the mathematics. A number of good links to more information.
The subject of PID'ing Silvia is well worn on CG, alt.coffee, and of course "PID"
is mentioned frequently on HB. Below is a small sample:
By the way, I got better quality search results on google from "proportional derivative controller" rather than "PID."