Is it legal to build a competition robot in the Withholding Allowance?

Provided that all custom/modified/assembled parts weigh less than 30 pounds, is there anything actually barring this? R23 only counts custom parts, and allows those parts to be switched between events. CIMs and other motors with uninstalled pinion gears count as COTS, as do unassembled gears/gearboxes, which are generally the heaviest individual parts of a small robot. Intake wheels and drive wheels if removed would also not count against the limit. Likewise, an unassembled electrical system would be COTS, though it seems inadvisable to wire the bulk of even a small robot at a competition the day before matches. Practicality aside, is there anything stopping a team from building a 25-30 lb. frame with minimal custom parts, reassembling everything on site in the pits, then submitting that robot and the associated BOM for qualification matches after inspection?


It’s as it states for anything in your withholding allowance so yes you are allowed to build a frame and bring it in, anything you bring counts as withholding allowance on the frame or structure for its weight


Keep in mind it is 30lbs total and not individually, your best advice is to use the lightest, strongest materials for the structure, square aluminum tubing is a great way to go

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We have a lot of 1/16" 2" x 1" tubing, a CNC mill, and a Taz 6; we were planning on pocketing as much as possible from the tubing and printing out gearboxes for easy assembly/alignment. With that, it is feasible to get a drive base to maybe 5 pounds before COTS parts without too much difficulty. Thank you for the advice, though!

You’re welcome if you have any other inspection questions I’ve found a link to this years inspection EDIT: It would be best if you followed up to date with the inspection list here at

it has been done before

You wouldn’t be the first team to do this. There are a number of teams which have essentially built a new robot from COTS and a withholding allowance on the first day of a three day event. Especially if you do this at a second/third event, be mindful of C5 - never have anything which could be perceived by an astute observer as two robots simultaneously, and transfer enough key components from the “old” robot to the “new” one that you can claim with a straight face that the transferred components “are” the robot from a reasonably astute point of view.


We did something kind of like this for championships last year. At week 4 during finals, we realized that a drive gearbox on our robot was going to need either replacing or repair. We worked through a few different repair scenarios and timed them before Houston, and decided to build a new identical drivetrain (chassis, gearboxes, and motors only) with the withholding allowance and COTS. It just seemed like the more reliable method to bring the replacement gearbox in assembled, rather than wait to get our hands into it for repair until pit day. It all worked out well. Hardest part was probably figuring out what to leave disassembled and how to split components between airline checked bags and carry on. Inspectors did stop by to check with us that we did not have two robots at the event, but otherwise it was not an issue. It was a fun challenge, maybe will try again because we can. We did a time lapse of the work in the pit, though we didn’t record the whole time unfortunately:

Ok, thank you!

@GeeTwo, as far as avoiding violating C5: Would moving the RoboRIO, a few (4?) motor controllers, and maybe a Versaplanetary or two count? The plan is, as of now, replace the entire drive base and likely any mechanisms (so virtually every structural element). It seems like removing those components would create a pretty clear husk of a robot, but I honestly don’t know if that would still count as bringing 2 separate robots to an event.

The rules are quite vague on this, but if I were going this route and were building a new chassis, I would try to transfer key identifying items from the bag to the “new” robot, such as the RIO, RSL, radio, PDP, and main breaker. Removing these things from the thing you put in the bag makes the rest of the bagged assembly clearly “no longer the robot” in a way that removing motor controllers and gearboxes does not.

Please don’t rehost the inspection checklist by uploading it to CD like you did. Instead, link to the manual page where the current version is linked from. If there is an update (and there likely will be), then the one you posted will be out of date and mislead teams that find it.

@Jon_Stratis This is the current version as of today I’m not sure what you mean

If the list is updated in the future, the pdf you uploaded will be out of date. Linking the webpage that hosts the updated pdf instead of uploading the pdf itself to CD will prevent this from being an issue.


I mean if they update the checklist tomorrow, then it will be out of date. At that point, anyone that comes to this thread and downloads the one you uploaded will not be getting the most recent one. As Frank said in his blog at the start of the season,

A plea: Please do not re-host or redistribute the content posted by FIRST . All are welcome to post links to our content as long as the content itself remains on our servers. The content could change at any time after Saturday’s Kickoff (though after Kickoff, we promise that we try to only change things we think are really broken), and by linking to our content instead of hosting, we can make sure everyone is getting the most up to date information.

Alright thanks for notifying me on this thought it was just the game manual that changes

Check out this TBA blog to see how 558 basically does what you are describing.

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