⁶ CIM drive-train brown out

[KrazyCarl92]

Originally Posted by MaGiC_PiKaChU

We had a 6-CIM drivetrain with our 2014 bot. No brownouts. We were running 2 bags and/or minis along with it

It's a different ball game now that the roborio has certain brownout conditions in place to prevent mid-match rebooting loss of comms. I have heard several teams say the brownouts were not noticeable to them while driving a 6 CIM drive. However, we do not have a representative sample because last years game did not subject motors to the normal rigor of an FRC game that includes defense or other high torque situations such as field obstacles.

Your set up with driving each motor to a wheel independently is a generally poor design choice. Here's why:
1. You will need to have a gearbox for each wheel. This will be heavier.
2. With a 6 wheel drop center drive, one pair of your corner wheels will not be in contact with the carpet when flat on the ground (or it will at least have substantially less normal force). It will therefore be unable to transmit any force to the ground (or substantially less). If you chain your wheels together and have 1 central gearbox on each side, the torque could be transmitted to another wheel to make use of the extra motor power.
3. When in situations like a pushing match or obstacle traversal, your wheels may have abnormal weight distribution. Since their normal force on the carpet or otherwise field surface is unequal, different wheels may begin to break traction and slip at a lower torque than others. If you had the wheels chained or belted together you could essentially allow the motors to distrubte the torque to which wheel it is needed on, and avoid this loss of traction issue. In this years game in particular, if you picture a situation where you're caught strangely on an obstacle and only 2 of your wheels contact a field surface you would only be able to use 2 motors worth of power to drive by your design.

There are plenty of performance related reasons to do a single gearbox per drive side with chains or belts or gears connecting all the wheels and physical justifications behind them. Hope this helps.