Looks like we will be seeing a lot of pretty ridiculous arm joints this year. Double strand #35 is rated at something like 1500 lb working load. (note, we have two single strand #35 for our main arm joint)
I have a feeling that team 121 is trying to point out that they will have a 4 wheel drive this year by the two sprocket and the chain. And the output shaft there is referred to the transmission output shaft. 
-Arefin.
Shouldnt you be more worried about your chain slipping than it breaking? We only used one chain last year so im not exactly an expert but it would seem to me that one chain should be plenty for just about anything in FIRST.
It looks like an industrial machine with that paint on it.
Why would you paint your chain anyways? Sounds like a good way to sieze up the links, if you ask me
Arefin, that is very unlikely that that is a drive train chain because it is actually one chain, not two, and there is no reason they would need such a monstrous chain for their drive train.
that’s what i was thinking too… Seems like overkill for FIRST
If that’s what I think it is, that’s very mean.
I approve. 
MrToast
Its a shop machine. lol.
Not a robot teaser.
Not a bandsaw is it? something that moves similarly to a band saw anything that out in the open is moving not turning a bit or piece.
I do agree with Arefin that it looks like a 4 wheels drive train but i dont think that the shaft is the output of a transmition. About the paint it looks nice…
David
You guys honestly think that’s part of the robot after watching American Robot?! :yikes:
Dave
Ok, you guys are quite astute…It is not actually part of our robot.
I will give 100 points to anyone who can guess what it really is from… It is on something that we found in the navy warehouse that we work in. It is really big.
Rob
Can I guess? http://www.davedelong.com/gallery/misc/emoticons/angel.png
Actually, I don’t remember what it is, but i know exactly where it is and what it looks like. http://www.davedelong.com/gallery/misc/emoticons/tongue.pnghttp://www.davedelong.com/gallery/misc/emoticons/erm.png
Dave
is it a mechanism for raising something? like a door or elevator?
Logic says that since only about 10% of the chain is resting on the sprockets, then this is not the actual pivot point for the chain. I believe it is just a chain tensioner we are seeing to reduce flex in the actual chain run. It looks like the actual load bearing drive sprocket would be about a foot (or more) in diameter and located inside the limits of the chain guard guard that is showing in the top right?
As for it’s application? I don’t know.
Lifting relatively small (as far as Navy boats go) boats out of the water?
Wierd thing is, if it isn’t a torque transferring sprocket (just an idler or tensioner), why is it keyed?
To run the shaft on the bearings so they don’t put wear on the shaft itself.
Setscrew wouldn’t do the trick?