Frame Material

[HarveyAce]

Our robot did okay at the competition, but when it underwent the stress of all of the banging and rough nature of the game Breakaway, the frame tended to warp. It was our rookie year and maybe i shouldn't be so harsh on it, but I wouldn't chance using it again for holding much weight.

[zbanks]

In my experience, the kitbot generally works well enough.

Sure it will warp, but it seems completely worth the weight savings. If you notice that it starts to warp, it's generally easy enough to add extra support.

One year we decided that kitbot was too warpy and we needed to use a stronger frame. We built a double-tiered frame out of aluminum stock that is roughly equivalent to 80/20. That was a bad life decision. It still warped because the corners were the weak spot. It was also incredibly heavy.

Kitbot is a strong option if you don't have time to experiment with a lot of different things. It will warp, but the corner gussets are strong & its easy enough to add reinforcement. (80/20, although overkill, fits snugly inside the C-channel...) Most importantly, make sure the path from transmission to wheel is rigid: if that starts flexing, you'll encounter chain issues.

[Kevin Sevcik]

We've been building off the kit frame for a few year now, and haven't had any issues with reliability or warping. I think last year was a bit of an outlier. The standard config with the wheel brackets wasn't rigid enough against the diagonal stresses from the chains, so thatb caused problems for teams. With the flat field and standard mounting this year, I think the kit frame will be plenty strong enough for most teams.

As for our usage of it, we've been building it mostly standard, and then putting uprights into the corners that bolt into the side of the corner bracket. It tightens up the corners nicely as well as giving us material to build a second deck on, etc. We build the rest of our frame out of various sizes of 0.065 square tubing, which gives us a nice light but stiff frame

[sdcantrell56]

One very easy way to pretty much fix all the warping problems is to mount a continuous piece of 3/8" baltic birch plywood to the bottom of the frame. Only cut out where you need to for the wheels and chain. This will greatly strengthen the frame plus give you a non-conductive mounting surface for all the electronics.