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Unread 29-08-2012, 15:14
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Re: pic: 2012 frc971 transmission

Quote:
Originally Posted by DampRobot View Post
Sure thing. I've always designed belt setups just like chain, with a tensioner/sliding endpoint, so this effected my WOT:


Category Weight Chain Belt
Availability: 4 4/16 3/12
Weight: 4 3/12 4/16
Manufac.
Speed: 3 4/12 4/12
Total: 11/40 11/40

The thread I was referring to in terms of efficiency can be found here: http://www.chiefdelphi.com/forums/showthread.php?t=76964&highlight=belt+chain+effici ency. I believe their methods were quite scientific and methodical, and they concluded that belt was 6% "faster" then chain over a given distance.

6% used to seem small compared to the difficulty of obtaining belts that can only be used for one application. I suppose that not having to do sliding tensioning blocks would be a plus for chain, but I'm really not that sure. Although teams certainly have been successful with it, center distance design with belt or chain has always seemed like a technique that could tend to cause problems when you actually try to put it together.
6% is substantial when teams are operating on fixed power.

The argument that the lead time of belts is a disadvantage isn't really the entire story there. Do teams really build their entire robots with no parts that have a lead time? We have several suppliers of belts, and we KNOW that we can get any given belt we need in reasonable time. We also make sure to design around belts that exist and are in stock, which is trivially more effort than designing around a chain spacing you know.
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