Challenge Follies -Reply

[Hans Blom, 950919]


your control system must have a precise measure of its own output


Yes. Doesn't yours?


No. Of course not, Hans. You've been making this up. A control model
(PCT) doesn't use u in the computation of the error signal that
drives u.

Me, now:
No, I'm not making this up, as Bill has acknowledged already. Please
read your own (or Bill's code) of the "classical" PCT-controller with
its "leaky integrator". In all of these controllers I find a state-
ment that starts with

  u := u + ...

In more accurate terminology:

  u_new := u_old + ...

This means that the controller, in computing its new u, uses (and
therefore must know!) its previous u.