Our robot has been having some trouble getting over the barrier that we built based off of the Team Field Drawings, but we now believe that the drawings might be incorrect.
According to page 72 of the Game Specific Drawings for the competition fields, the top of the barrier is exactly 4 inches above the carpet, as shown below.
However, page 3 of the Team Field Drawings has teams building the barrier with a piece of 1/2 inch plywood on the bottom, followed by a 2x4 (of course actually 1.5 x 3.5), and then another smaller piece of 1/2 inch plywood on top. Added all up, that would give the barrier a total height of 4.5 inches, as shown below.
Have any other teams notice this? Has it caused any problems for your robot? If so, what have you done about it?
As far as I can tell, the Wooden Barrier is an accurate functional replica of the field barrier but it’s not perfect. From what I’ve seen if a robot can climb the wooden barrier then it can climb the field barrier if it’s got enough traction against the steel.
If you look at the drawings, or a Barrier constructed from them, you’ll notice that the effective height of the Wooden Barrier is only 4". The difference lies in the fact that the 4" bump is now about 3/8" - 1/2" higher from the floor than a normal barrier because the entire barrier is sitting on a 1/2" step that extends out on either side by 4" - but I believe (Or at least our testing has shown) that this is a non issue because the robot’s drivetrain should come in contact with this step before touching the barrier, effectively making the barrier the leading edge of the of the Drivetrain ‘sees’ the correct 4" Tall.
If you want to make the step an non-issue you could attach a piece of 1/2" plywood to extend the step out further so that your entire robot is sitting on it when you go to climb the 4" tall portion of the barrier (I’d suggest covering this additional piece of plywood with carpet). If you want to get really precise, you could cover the 4" of the step touching the barrier with 1/8" steel sheetmetal to accurately represent the competition barrier.
Interestingly enough from what I’ve found, the competition barrier might actually be easier to climb then the wooden barrier for some robots because of how the edges on the competition barrier are actually rounded from the bending process - assuming the robot has enough traction against the steel barrier.