Bruce in Alaska wrote:

You missed the point entirely with the above. The PWM for the rudder
position is set in the controller design and does not care what mechanism
is moving the rudder, andlong as it has postive control over that
mechanism. (ie move right, oir move left) The rest is already designed
into the controller feedback loop, and a nonissue for the user. It
could be an issue if you were designing an AP controller from scratch,
but that is not the case in this thread.

Unfortunately that IS the case. He wants to control the drive from a
simple tiller pilot output. That is just forward and reverse. No PWM,
no braking, no rudder angle input, no fancy logic. I don't see a way to
do it in the first place but a balanced double ended cylinder will make
what ever solution he comes up with a whole lot simpler.

-
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
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