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Unread 11-11-2014, 21:32
ajlapp ajlapp is offline
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AKA: Anthony Lapp
None #0118 (Team RUSH and Robonauts)
 
Join Date: Sep 2001
Rookie Year: 1996
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Re: pic: Frog Force 503 Omnitank Drivetrain (rAC)

Quote:
While not a member of 118, I have had their systems explained to me by their students, so I can provide a little insight into why they do what they do.

They like the chain in tube because of the small space savings (and no bearing blocks to manufacture) but mostly because it requires no tensioning. The chain may stretch, but there is nowhere for it to go, so losing a chain isn't possible. Note that this doesn't mean the chain is necessarily strong enough for whatever load you are applying, it just means it won't derail as long as you stick it in a small enough space.

The double sprockets don't actually run double chain. Remember that the center wheel(s) are connected to the wheel in front of and behind it, so they have two chain runs on their axles. The people designing/building the drive found it simpler to just put double sprockets on all the axles rather than make spacers just for some of them.
This info is accurate. We don't run tensioners as they're not needed. We don't run double chains, but there is a double sprocket and two runs easily fit.

118 runs a modified version of the production units available from www.Team221.com. 118 has used them for the past two seasons with excellent results.

Editorial Note:
If you're breaking #25 chains in your drive base, you're doing something wrong.

It is very hard to generate a enough force in your drive base to violate the working load rating. Especially if you avoid master links...
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Anthony Lapp
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