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Author Topic: I need some input  (Read 678 times)

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Offline acar25Topic starter

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I need some input
« on: August 26, 2010, 12:05:35 PM »
I have had an idea of making a robotic arm. A one-jointed arm, that joint being the elbow.

I need to control a servo with a potentiometer. when the potentiometer is turn farthest left (or lowest value) the arm is contracted. When the potentiometer is at the farthest right (or highest value) the arm is extended.

Any advice?

Offline futmacl

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Re: I need some input
« Reply #1 on: August 26, 2010, 12:09:48 PM »
Any advice?

On what, specifically? Finding a servo? Building your own servo? Interfacing it to something (if so, to what)?

EDIT: Oh, didn't catch your point - driving a servo based on potentiometer reading, versus just controlling a servo that contains a potentiometer.
« Last Edit: August 26, 2010, 01:02:03 PM by futmacl »

Offline Soeren

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Re: I need some input
« Reply #2 on: August 26, 2010, 12:57:53 PM »
Hi,

I need to control a servo with a potentiometer. when the potentiometer is turn farthest left (or lowest value) the arm is contracted. When the potentiometer is at the farthest right (or highest value) the arm is extended.

Any advice?
Discard the electronics in the servo (except the H-bridge). Then use a dual comparator chip (eg. LM339) to make a window comparator that compares the two potentiometers (the one in the servo and the external one) and control the bridge from the outputs.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

Offline Razor Concepts

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Re: I need some input
« Reply #3 on: August 26, 2010, 07:09:49 PM »
Or buy a servo driver for $5

 


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