Were planing our bumpers for this year and were wondering if we can put a piece of aluminium in between the wood of our bumpers and our robot frame?
The main thing to watch for here is the 1" hard parts rule (R31b). If you put metal between the frame perimeter and the wood, you’re decreasing the amount of metal and other hard parts you can put outboard of the bumper wood.
Is the metal part of the BUMPER? Then beware of the 1" hard parts rule as already noted.
But is the metal part of your ROBOT? If so, then you’ve increased your FRAME PERIMETER - make sure you still comply with the size limit!
I think it depends on the shape/size of the piece of metal. Strips of angle on
the edges of the plywood are legal. Backing the entire back face would not be.
To help you answer the question @GaryVoshol asked, Blue box from R30 (emphasis mine):
If a multi-part attachment system is utilized (e.g. interlocking brackets on the ROBOT and the BUMPER), then the elements permanently attached to the ROBOT will be considered part of the ROBOT, and the elements attached to the BUMPERS will be considered part of the BUMPER. Each element must satisfy all applicable rules for the relevant system.