I’ve read the rulebook through a few times and haven’t found anything relating to this. The BUMPERS are not part of the WITHHOLDING ALLOWANCE, but they are still brought along with COTS parts, separate from the bagged ROBOT.
Our ROBOT has different modes, and one of these modes requires a BUMPER cutout whereas the other one does not. Can we have one set of BUMPERS with a cutout and another set of BUMPERS without a cutout? As long as they are both meet the criteria would this be legal?
I can’t find any rule that prohibits this. R26 says the robot must be able to display red or blue bumpers, R28 says each set of bumpers must weigh no more than 20 pounds.
After having spent a week 1 event painfully inspecting (rejecting) bumpers all day for 2 days, if you can build multiple sets of bumpers that meet the rules you get a gold star. It’s hard enough to get a team to make 2 sets that pass.
I don’t feel like going back and checking how the bumper rules differ between this year and last year, but I know last year a number of teams made multiple sets of bumpers and they all passed inspection. One set was slick to avoid defense, and one was rough for playing defense.
I don’t see why you wouldn’t be allowed to switch so long as both sets of bumpers are legal. I also don’t see why you would want to switch bumpers for different auto routines instead of always going with the cutout bumpers. Seems like an unneeded hassle to me, and it lengthens the time needed to change autonomous routines.
More than 1 set of Bumpers is fine. You just have to let the Inspectors know during weigh-in. The weight of each set is recorded, so you have to let them know you have more than 1 set so they can record them all (and also verify that the bumpers weigh less than 20#).
It isn’t for auto routines, the different modes are different mechanisms being swapped around for strategic purposes. Some go over the bumpers, some need the cutout.
All right now I need to see this. Swiss army bots in FRC has been a theory I’ve pondered for years.
Haha, it isn’t optimal by any means. It’s just a result of me staring at Solidworks for 12 hours and realizing I couldn’t fit everything into one assembly with existing space constraints. Split them into 3 different things. 2 are interchangeable and 1 will be on all the time.
The bumpers should just be weighed as a separate set like if you had one set in red and one in blue.
Just remember to make sue the weight of all the different components must weigh be under 120lbs. for example if you have a gear mechanism and a ball mechanism that can get changed out the robot plus the gear mechanism and ball mechanism must weigh less than 120lbs. Rule R04.
Boy, does this bring up some old memories: https://www.chiefdelphi.com/forums/showpost.php?p=711900&postcount=35
In 2008, we on 1519 built a dual-configuration robot which was deemed illegal by the GDC. Ultimately, the issue was “there is no way that the full set of bumpers (both sets) can be mounted on the robot and satisfy Rule .”
However, that’s ancient history. I think that your dual-configuration bumpers should be allowed if the full set of bumpers (for either color) satisfies the bumper weight limit.
Yet, it doesn’t matter what any of us here on CD think. All that matters is what the Lead Robot Inspector at your first event thinks. I thought our dual-configuration robot was legal in 2008, too. 
PS: As a fallback if your approach is deemed illegal, can you just use the “with cutout” bumpers on the robot all the time?
In case the lead inspector deems our attachments and bumpers illegal, we would probably just roll with the full set of bumpers. We could still shoot/intake/gears/climb albeit at worse efficiency. The cutout-mode is the more strategically viable option, however. (based on what I have seen in week 1)
You can swap out to your heart’s content if the robot, with both sets of mechanisms, is within the 120# limit.
If they are not, then you will need to be reinspected with every change.