Author Topic: Slide Pot  (Read 1117 times)

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Offline CommanderbobTopic starter

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Slide Pot
« on: January 31, 2010, 04:54:23 PM »
I'm looking for a slide potentiometer that has a travel of at least 6". The longest one I've found was 100mm (about 4"). We need it to be able to tell where a pneumatic piston is.

Offline Soeren

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Re: Slide Pot
« Reply #1 on: January 31, 2010, 05:05:15 PM »
Hi,

You could get lucky searching among professional stage lightning sites, but be ready to pay through your nose if you do.

Alternatively, you could use a system like what's used on old radio scales, with a string where one point is moving with the piston and then driving a rotary pot with a pulley with a diameter made to match the length of travel to the around 270° travel of the pot.

There are other methods as well, but how precise do the readout need to be?
Regards,
Søren

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Offline z.s.tar.gz

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Re: Slide Pot
« Reply #2 on: January 31, 2010, 07:15:30 PM »
+1 for sting and pulley. I've never seen a 6" linear pot before.
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Offline Soeren

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Re: Slide Pot
« Reply #3 on: January 31, 2010, 09:30:33 PM »
« Last Edit: January 31, 2010, 09:32:28 PM by Soeren »
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
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Offline duste83

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Re: Slide Pot
« Reply #4 on: February 06, 2010, 08:02:31 AM »
why don't you just use a lever action with a smaller linear pot.?  you have one end on a pivot and the other on the moving object and the shorter linear pot. in the middle.

Offline nottoooily

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Re: Slide Pot
« Reply #5 on: February 06, 2010, 05:21:53 PM »
Yea these are used in industry like what Soeren said, but you pay a heavy price for reliability and ruggedness.

You can also make you own from a straight or spiral length of electric heater wire/etc.


I'm looking for a slide potentiometer that has a travel of at least 6". The longest one I've found was 100mm (about 4"). We need it to be able to tell where a pneumatic piston is.

Offline galannthegreat

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Re: Slide Pot
« Reply #6 on: February 09, 2010, 12:34:58 PM »
I found one on this site that has 5 inch travel. It's motor driven though, but if you don't need the motor you can just remove it.

http://www.alltronics.com/cgi-bin/category.cgi?item=28P006
Kurt

 


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