Log in

View Full Version : Team 4461 Preseason Drivebase

Chris Calvin
03-01-2015, 01:32
Hello CD, First Post!

Our preseason drivebase is here (https://github.com/FRC4461/SolidWorks). The drivebase is constructed from sheet metal and 1x3 tubing. We opted for 4" colson wheels driven by 9mm GT2 belts (42 tooth pulleys) and a 3 Cim gear box (no shifter).

Let us know what you think.
asid61
03-01-2015, 02:21
Welcome to CD!
So I've got your drivetrain open right now, and I'm noticing a few small errors or odd choices here and there:
-Your sheet metal bends have a very small radius. Are you sure these radii are correct? Check with your sponsor to make sure.
-Your gearbox gear spacings are off! The first stage of gearing is okay (1.602", that's fine) but the second stage is 1.620"! Is there a reason for this, or did you just misplace a zero?
-I like the 6-cim drive, but it's almost wasted on a 14:50 x 14:50 reduction to 4" wheels. You're geared for 7.2fps according to JVN frer speed, which is pretty slow. To get the most out of your drive, you might want to bump things up to a 14:42 or 14:44 reduction for the second stage to get a free speed of 8.2fps+. You still won't blow your 40a breakers on the cims in pushing conditions at 140lb robot weight.

As a side note, you should consider changing your naming system. The way you have it now, there are tons of oddly named parts. Using a numbered system or a number/name system is a lot easier to keep track of IME. Last year I was essentially stuck with the job of keeping the CAD clean, which was very tricky when everything had odd names and weren't kept track of. Also consider using folders in assemblies (right click -> add to new folder) to keep track of stuff like screws and nuts and plates.
I like your subassembly system. You only have four pieces in your final assembly, which is really, really good. Keep up the good work, and good luck!

EDIT: Also, Solidworks materials! Save 6061 to your favorites list. Two clicks and you've got the part to the right material. Makes rendering a breeze, makes drawings easy to material (even rookies can do it!), and makes the final assembly look nicer.