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Unread 06-12-2011, 03:06
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biojae biojae is offline
Likes Omni drives :)
AKA: Justin Stocking
FTC #5011 (BOT SQUAD) && FTC#72(Garage bots)&& FRC#0399 (Eagle Robotics)
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Join Date: Oct 2008
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Re: Grabbing oblong objects

Quote:
Originally Posted by AdamHeard View Post
Without knowing the exact mechanical design it's hard to give completely valid advice.
Ok. Here's the design.

It is a chain based fourbar grabber. It is powered by 2 continuous turn servos.
Both arms are powered and move simultaneously. The potentiometer is part of the gear reduction.

Attached is a sketch.

The black object in the center is a crate.
The blue members are the C channels.
The red circles are sprockets/gears.

The sprockets that connect to the gears are mounted solidly to each beam, so that they do not spin, thus providing the fourbar motion.
The gears turn the black channels.
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Last edited by biojae : 06-12-2011 at 03:19. Reason: added side view sketch