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Unread 06-29-2015, 08:34 AM
Nathan Streeter's Avatar
Nathan Streeter Nathan Streeter is offline
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FRC #1519 (Mechanical MAYHEM)
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Re: pic: Octocanum Module

Very innovative design; I don't think I've ever seen something similar!

The design seems generally very good. Obviously you have a pretty high weight per module, but it's not bad at all considering you have a mecanum, 2" wide colson, all your gearing, and a CIM and MiniCIM. You could easily drop MiniCIMs on the front or something like that to save an easy ~5 pounds on the robot. I'd say to keep the 2" colson... if you're bothering to have a high-torque traction mode, I'd say don't skimp on it. Now, a fair question could be, "how much do you really need the traction mode?" I think many teams (my own included) tend to want to add all the 'bells and whistles' without really doing the strategic game analysis.

My one comment about the integrity of the design is about the idler axle. I've never used a single bearing on an axle like that... does anyone else have some experience with an idler shaft with gears on each side supported by only one bearing? You could always put a .875" press fit on the back side so you could put a turned down shaft through through the module if you need more support. Seems like 3/8" aluminum would be more than enough for that.

EDIT: I'm guessing you're fully aware, but your mecanum mode is geared pretty high. It may end up working well for you (particularly in some games), but I'd honestly only gear a >110lb robot that high in 2011 and 2014 of the games since 2005 (although I think fair cases could be made for 2006 and 2008). I realize a fair bit of this is a 'strategy/design style' though. :-)
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Student: 2006-2010 (#1519)
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Last edited by Nathan Streeter : 06-29-2015 at 08:51 AM.
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