How do you you choose the dimensions for your robot chassis?
Figure out how you want your robot to play the game, Figure out what drivetrain you want to use. Think about how stable the robot will be, with the wheelbase, track width, and center of mass it will end up with. Think about how the “mechanisms” will fit on the robot, including any gaps in the bumpers to allow robot parts or game pieces to move in or out.
Also keep the size to less than the maximum allowed in the rules. We like to make ours an inch smaller in each dimension, just to make sure we will pass inspection.