Does anyone know of a sensor that determines position, feeds back a signal
to both allow position and preselection of motion? I am trying to fabricate
a flap handle that when put in a position (say 30 deg flaps)
actuates the motor; the sensor senses when the motor (flap) is there
and then shuts off. Seems to me cowl flap linear actuators might do
that? But I already have a motor and a way to sense flap position. I
just need to feed it back and control it at the flap handle. Marc

Any potentiometer will work as a sensor.
http://parts.digikey.com/1/parts-kws/a-250k-potentiometer

Paul Lamar

Out put stage attached. The word I was looking for was voltage
divider for the flap position selector switch. You will need a pot
with as many turns as ball screw shaft (or proportional gearing).
C. Smith

Paul,
           Agricultural combine harvesters have just what you are looking
for, which they use to set the sieves and rotors at pre-set
positions..  As a spare part they charge $1000, but can be bought
elsewhere for a few hundred or less, (the actuator.)  The brains I
have never had to look at, but you could find a local farmer and
look at his machine.  The Case 8010 uses them as I suspect New
Holland or any later harvester in your area.  All the driver does is
hit the button and everything is set to whatever settings have been
pre-set to that crop, say wheat, if you move into corn, again just
hit the button and all is altered by the linear actuators.  Sure
beats the old days when at each different crop it took a half hour
with spanners to do the same and you came out covered in chaff and
crap and itched for the rest of the day.  Neil.

Got a call one time about a combine either cracking the kernels or throwing
over. When I got there the son and hired hand were there and had a couple of
24's with them. They were PO'd when I would not look at it until I had all the
keys and disconnected the batteries. NOTE: the only thing more dangerous than
a dumby, is a dumby that thinks he is smart, Or a drunk. See previous. Found
the dumbies were tightening one side and loosening the other. 1/8" clearance
on the one side and about 5/8" on the other. Yup the new stuff idiot proofs
that. Like you said Neil, cleaner too.

Dale Davies