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Author Topic: Choosing angle sensor for robot arm?  (Read 1759 times)

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Offline anh_risnTopic starter

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Choosing angle sensor for robot arm?
« on: May 16, 2011, 07:45:23 PM »
Hi all, I'm getting difficulty in finding best angle sensor for my robotic arm, can anyone tell what is the best angle sensor for robot arm?
where I can buy it? thanks.

Offline rbtying

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Re: Choosing angle sensor for robot arm?
« Reply #1 on: May 16, 2011, 07:56:29 PM »
A potentiometer.

http://www.sparkfun.com/products/9941 <-- this is one, but if you're buying a bunch a dedicated parts supplier (digikey and suchlike) are better on pricing, by far.

Offline anh_risnTopic starter

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Re: Choosing angle sensor for robot arm?
« Reply #2 on: May 16, 2011, 08:06:42 PM »
Is it reliable and durable? maybe sometimes the resistance will chance a bit or broken because of the mechanical movement

Offline anh_risnTopic starter

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Re: Choosing angle sensor for robot arm?
« Reply #3 on: May 16, 2011, 08:20:06 PM »
isn't there any special potentiometer for robot arm?

Offline rbtying

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Re: Choosing angle sensor for robot arm?
« Reply #4 on: May 16, 2011, 08:40:06 PM »
A potentiometer is usually quite reliable, as long as you mount it correctly.  Mounting it off-axis will lead to the issues you mentioned.  There probably are special potentiometers for robot arms, but they're quite expensive and frankly unnecessary unless you're looking to make an industrial-grade device (be prepared to throw away lots of money if you are).

How fast will this arm go? That will be the primary source of wear/tear.

Offline anh_risnTopic starter

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Re: Choosing angle sensor for robot arm?
« Reply #5 on: May 16, 2011, 08:49:51 PM »
Can you find me the site which has special potentiometer? perhaps I will check first.
and thanks for your advise.

Offline anh_risnTopic starter

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Re: Choosing angle sensor for robot arm?
« Reply #6 on: May 16, 2011, 10:50:52 PM »
Hi all, can u also suggest me common rotary encoder? low cost rotary encoder should be better, because my hardware didn't need very fast rotation.

Offline rbtying

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Re: Choosing angle sensor for robot arm?
« Reply #7 on: May 16, 2011, 11:02:36 PM »
Can you find me the site which has special potentiometer? perhaps I will check first.
and thanks for your advise.

Some quick google searches should bring up information here.  Alternatively, read datasheets and look up parts on digikey.

Hi all, can u also suggest me common rotary encoder? low cost rotary encoder should be better, because my hardware didn't need very fast rotation.

Rotary encoders are much more expensive than potentiometers: where a decent pot might cost ~$0.50, a non-mechanical rotary encoder will cost ~$20.00.  Rotary encoders are also better for faster movement as compared to slower, since they have lower resolution, where a potentiometer is more cost-effective.

P.S.: Please don't double-post, just edit.

 


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