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Unread 29-10-2008, 17:24
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Madison Madison is offline
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FRC #0488 (Xbot)
Team Role: Engineer
 
Join Date: Jun 2001
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Location: Seattle, WA
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Re: pic: FRC488 - 80/20 Drive Train

Quote:
Originally Posted by AndyB View Post
Madison, this looks like a very simple, easy to put together design.

The only weaknesses are, in my eyes, angular clearance for ramps.

Assuming the wheels are centered at 3/4" above the 8020, and positioned about 3.5" back from the inside of the front rail, that only gives you about 17 degrees of angular clearance. But for a flat-field application, this looks like a very nice drive that you could easily modify at any point.
Yeah, this can clear a 17* angle, but nothing greater. If there's anything steeper, we'll figure out how to deal with it as a special circumstance -- or we'll turn the chassis upside down.

Quote:
Originally Posted by qwertyuiop[]\ View Post
Why do you need a six wheel robot if you are using omni's? also watch out, 8020 bots get heavy, fast. on our 2006 robot we essentially built our entire robot out of 8020. There is alot of un necessary weight in 8020. Do you really need all for slots in the metal? it is very strong and is very fast, so if your going for a fast build this is what you want. Also, what size 8020 are you using, the inch or half inch?
6WD does a bit better at getting over obstacles -- whether those be field elements or game pieces. Again, the simplicity here is that we can swap in any sort of wheels we'd like easily -- and we can add or remove "drop" as necessary.

The profile shown is 1010 -- 1" square.

We have a good history of building reliable drive trains that are also very light. We've been working lately on minimizing manufacturing time, so we're conceding some of the features that make things light in favor of those that make them quick to build.

Quote:
Originally Posted by Andy Baker View Post
You are right, as the t-slots do allow for the t-slot nuts to slip. However, another thing to do besides drilling a hole is to just add another t-slot nut to back up the initial nut. If there are 2 in a row, and both are tightened well (and checked routinely), then the slippage does not happen.

Andy
That'll be Fred's job. Fred is the advocate for 80/20 on our team and even then we use it sparingly. If it breaks, it's his fault.
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