On Fri, 2 Jan 2004 07:12:52 -0500, you wrote:
>In a nutshell, they used a DC gearhead motor with a lever arm mounted on=
 the
>shaft.  The end of the arm was connected to the inside of the throttle
>cable.  The outside of the throttle cable was clamped to the unit.
>
Sounds similar to a cruise-control I built back in 1995 using a 68HC11E2
for my F-150. I used a stepping motor driving a gear reduction, with the
lever arm on the end of the driven gear connected to a standard throttle
cable.

>The
>outer control loop adjusted the motor position to keep the engine speed =
at
>the desired value.  The engine speed was measured by feeding the =
tachometer
>pulses into a CCP input.
>
In my case the idea of course is to keep the vehicle speed constant, the
speed being derived from the 8000 pulse per mile signal they use to
run the speedometer. No inner control loop was need due to using the
stepper motor instead of DC gearhead motor.

Much to my surprise, that thing is still running even though it was
hand wired on perf-board :)

Bob

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