7103 Robo Remedy 2018 Robot and 2019 Preseason CAD Release

This Robo Remedy’s CAD Release for the 2018 Season and 2019 Preseason.

2018 Robot- Mr. J:
https://grabcad.com/library/team-7103-first-power-up-2018-mr-j-1

2019 Preseason West Coast Drive Chassis:
https://grabcad.com/library/team-7103-2018-off-season-west-coast-drive-1

Both of these models were made primarily by myself and our student lead. As far as the WCD, neither of us have any prior experience designing a custom drivetrain, so any feedback would be greatly appreciated.

It looks good for a first go! I couple things that I see in GrabCAD for the 2019 WCD (things can be messed up in GrabCAD that are totally different in the main assembly so if that is that case with any of these, bravo!).

  1. There are different wheels on either side of the drive train, even if they were the same size, I could see that causing some interesting issues with auto and other consistency aspects.
  2. There are no bearing holes in the drive rail, this would be good to add for exact center to center distances for the chain runs to be perfect (unless you’re tensioning somehow, which I didn’t see modeled).
  3. I don’t know much about sheet metal construction, but that is a very interesting use of the belly pan doubling as the front and back rail.
  4. A couple things have very little clearance. The battery and the battery casing are touching and the belly pan on the back of the CIMS are most notable.
  5. The gearbox mounting seems flimsy to me, I would add a standoff to the rail to make sure the bracket wouldn’t bend.

These are a few that I noticed, if you have any other questions don’t be afraid to PM me or ask questions.

Thanks!
As far as specific replies

  1. Yes, I’m well aware and would never build a robot like that! Those were simply to evaluate which wheel size would make the most sense; I put in both for ease of comparison.
  2. We plan on tensioning; I didn’t put holes there because wheels spacing is not firmly decided yet. Also, it wasn’t necessary for the sake of communicating the design idea.
  3. I quite like the idea! I took inspiration from this design:
    https://grabcad.com/library/us-first-robotics-west-coast-drive-system-2
  4. I’m also aware of that. The clearances are something we definitely need to work on, but I’m not particularly good with yet.
  5. That is also a thought I had after I drew it. It’s probably the most “iffy” part on here since it was drawn last and somewhat hastily.

Also, spacers will be used on the shaft in some obvious areas, but were not drawn.

I’m glad to see that where you saw issues isn’t where my initial concerns were! I was mainly concerned with if our sheet metal bearing holders and gearbox mounting would be able to support the load seen in a drivetrain. Also, I got a look at the 16 tooth sprockets when they arrived the other day, and they are a lot smaller than I envisioned, which also led me to question the integrity of the design.