legality of bolt and screw heads breaking plane of chassis meeting bumpers

[Jack Jones]

Originally Posted by Al Skierkiewicz

Kika and others,
The bumper design is intended to protect your robot. The GDC looked very hard at the effects on last year's damage and saw that bumpers, as designed, indeed protected our robots. Part of that design is the backup frame structure that prevents the bumpers from damage due to extreme flexing. Robot inspectors will evaluate each bumper implementation to determine if, in their opinion, the bumpers satisfy the rule. If anyone thinks that a 3/4" slab of plywood can absorb the hit of two 150 lb objects by itself should look for a post from Dave Lavery last year on this subject. The bumper system includes the backing frame structure and will be evaluated with that in mind. To that end, the GDC has allowed you to "pocket" the bumper (not drill holes through the material that will weaken the plywood) to allow the bumper to use the backing of the frame to strengthen the system. If you have two bolt heads at each end of the bumper that cause it to be separated from the frame for 35", some failure will occur. If your inspector asks you to make four small pockets, I don't think he/she would be out of line. Please be prepared to remount your bumpers during the inspection process following weigh and size. This step will be needed to evaluate the bumpers, check for height and ball intrusion and kicker extension if any.

If the GDC has looked very hard at the bumper design, then how is it they overlooked the most critical element - the plywood? There's a whole lot of difference between the 13 ply Baltic Birch plywood we use and the 5 ply soft-wood junk they sell at Home Depot. The ruling spends just one word, "plywood", on the most important part, but goes into great detail and updates about trivial air gaps. It just doesn't make sense!

Al - I'll bet you a dollar to a doughnut (no Krispy Kreme please) that a 35" slab of our plywood will take that hit.