Anticipation in Control System Theory

[From Bruce Abbott (950507.1855 EST)]

Remember our little discussion about anticipation in Rick Marken's control
system, the one that used both p and dp/dt in its perceptual input function?
Well, here's a little quote from a text on control system theory:

    A proportional-plus-derivative control system is defined as a feedback
    control system in which the output forcing function is a linear
    combination of the actuating signal and its first derivative. . . .
    This type of control system is often referred to as an ANTICIPATOR
    since the derivative control causes changes in the output forcing
    function in anticipation of an error in the immediate future.
    (Milhorn, 1966, emphasis mine)

So, Rick, you've designed an anticipator. Amusing twist, don't you think? (;->

Regards,

Bruce