Remote Servo / Stepper motor control

[MackMe06]

Hi,

I am looking for a way to turn something with either a servo or stepper motor but to control that servo / motor with an analogue knob. i.e. if I turn the knob to the left, the motor will turn left, and vice versa.

Is there a pre-made product out there that just has a servo / motor attached to a control knob where I won't have to do any programming or anything, just wire it up?

Any help here would be appreciated.

Thanks.

[Dave Dixon]

You might try search on synchro motors. All you need is AC voltage excitation, and they do what you are asking.
http://en.wikipedia.org/wiki/Synchro
Good luck,
Dave

[philba]

it depends on the motor you choose and how you want it to turn (continuously or ?).

Basically, I would use a potentiometer in a voltage divider and feed that into an ADC on a uC. Then in the uC, if the value goes below the mid-point, rotate the motor one way, if above, rotate the other way.

Until we know how you want it to rotate, it will be very hard to answer your question.

but to answer your direct question - no there probably isnt a pre-made product. You might be able to get by with a 555 timer and use a pot to change the duty cycle. the 555 output goes into a servo.

[dacflyer]

hi there , if your looking to control a servo with a pot,,here a link for you.. i hope you can view it..

http://www.conrad.at/goto.php?artikel=234915

if not then look to the left in the spaces below and type in the box that says Art - Nr. and type in 234915 and hit enter..

i got 3 of these kits when i was in Austria
its listed as a servo tester, its for testing model airplane servos or any other R/C type servo.. it gives you about 60° - 75° of swing
and the pot is a 5k size
the IC on it is a HFC4001BE and theres just a few other components on it.
i think i paid about 7.00 each for them, 4.95€ euro.

if you like i probably can print you the schematic if you want it..
then you can build it.

good luck

[slamer]

If you got about $20.00. This product might just do what you want. It's just a simple battery powered servo tester. Just turn the knob to move the servo.

http://www.robotlogic.com/product_servotester.html

[Externet]

Hi.
You can do that with any plain stepper motor driver that typically uses a 555; replacing the fixed resistor that sets the frequency with a potentiometer.
Miguel