pic: Team 5413 Stellar Robotics Offseason Drivetrain

[GeeTwo]

Originally Posted by Chris is me

Do you have a system to tension the chain when / if it stretches?

While it's not a real answer, you can see that there are four screw heads around each wheel shaft. This implies that there are actual bearing blocks on the other side of each plate, which may be adjustable.

Originally Posted by Chris is me

The integrated gearbox is great for reducing part count but not so great for serviceability and relies on your sheet metal shop's hole tolerances being as good as your milled plate tolerances.

Every bearing is (or should be) mounted in a block, not a plate. There is no need for a bearing where the main drive shaft passes through the inner plate, as it is supported by a bearing in the motor mount plate at one end and a bearing block screwed to the outer plate at the other end.

At first glance, I thought that you'd built an AM14U, then saw that the top folds were more like the U2, then noticed the gearbox and chain mounted inboard of the wheels rather than belts on both sides of the wheels, then the bearing block mounts. If you're ready to run a game with a single-speed 5:1 gearbox, this seems to combine the rugged battle tested design of the recent kit with some optimizations to reduce the footprint consumed by the belts/chains, and move the wheels farther out. I also like the complete "skateboard" capability that the recent kitbot lacks - if you put the control system (and perhaps battery) inside the volume defined by the inner rails, you have a level surface upon which to build your manipulators. By perforating every 1", you have plenty of mount points as you make adjustments. It's also a natural to mount a VersaFrame superstructure.

I would also recommend a belly pan, both for torsion control and for mounting your controls. Considering the belly pan makes me wonder - why are the bottom folds on the inner plate outboard towards the wheels, rather than inboard? If you put them inboard, you could mount your bellypan/control panel there. Likewise, if your top folds bent outboard rather than inboard, they would tend to act as chain guards rather than restricting access to the volume between the inner plates where (if you put your control system low), you are going to want to go. Or perhaps you are planning to mount the control panel/torsion control panel to the TOP of this chassis, and accept that when you need to work on the control system, you're going to lay the robot on a side/end/top so that you can access it from the side that normally faces the carpet?

Edit: I can imagine a truly elegant battery box that's accessed from below, in which the battery is held in place at one end by the front or rear plate, and an angle bracket keeps the battery from sliding away from that end plate or dropping onto the carpet.