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Unread 03-02-2014, 16:00
Oblarg Oblarg is offline
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AKA: Eli Barnett
FRC #0449 (The Blair Robot Project)
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Re: Help: Torque to Linear force conversion

Quote:
Originally Posted by pfreivald View Post
Yeah, I'd love to see it.
Here's a picture of the ratchet. You can see two severely gouged teeth, and these are on the lighter side of the damage we saw that year (we regularly rotated/swapped out ratchets as the teeth became useless). The pawl, too, took a beating in that mechanism, but I don't have it to show as it appears to have been lost.

http://imgur.com/8kZIYzK

To give a reference for the amount of force we were using on this thing, here's a shot where you can make out two of the (very heavy-duty) springs we used to power it:

http://www.flickr.com/photos/robotproject/5049734546/

In this picture it is set up for half-power, our full-power setup used four springs.

Quote:
Originally Posted by Dan.Tyler View Post
Relieve the load on the teeth before releasing the pawl.

You designed to have enough power to pull it back? Pull it back a half tooth more while disengaging the pawl.

Similarly, if using a dog gear method... Drive the motor forward and backdrive while pulling the dog.
Alas, we could not do this as we used the same motor to both tension and release our ratchet.
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Member, FRC Team 449: 2007-2010
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Last edited by Oblarg : 03-02-2014 at 16:10.
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