Rules regarding placing a coloured image against the alliance station glass

Is there any rules against placing a picture (for example a pink rectangle) against the alliance station window on the drivers side so that a robot camera could see this image to help in navigation? The only thing I’ve found is that you cant purposely disrupt other teams vision systems, but I don’t think this could be considered to be doing that.


I imagine that would be fine. Please note that H403 does prohibit that use during auto, so it would only be able to be used during teleop.

Let the ROBOT do its thing. During AUTO, DRIVE TEAMS may not directly or indirectly interact
with ROBOTS or OPERATOR CONSOLES unless for personal safety, OPERATOR CONSOLE safety,
or pressing an E-Stop. A HUMAN PLAYER feeding CARGO to their ROBOT is an exception to this

H403 seems to prohibit drive team interaction with the robot/driver station, not robot interaction with the driver station, so it should be fine – using arUco tags or something of the sort could be cool, and could push FIRST to start using them instead of retroreflective tape


Holding up a sign for a robot to interpret (as vision tracking or interpretation) would be indirectly interacting with the robot. It’s not just about the driver station, it’s also about the robot, thus the explicit exception for feeding cargo to the robot (which has nothing to do with the driver station).

As I interpret it, a drive team couldn’t actively raise a sign during auto (e.g. CheezyVision). However, if the drive team leaned such a sign against the polycarb during setup, and just left it there during auto, that wouldn’t be “interacting”.


This is also what I’m interpreting OP’s question as. I believe there’s been talk of this before at some point? It seems familiar (driver station vision localization) for some reason.

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Why not cover the lid of your drive station laptop with pink contact paper?


I was originally leaning towards “no” on this one, but the rules make it incredibly ambiguous, if not leaning towards “yes”. H303 divides items brought to the ARENA into the OPERATOR CONSOLE and everything else. A vision target would probably fall under H303.VI.b, an item allowed per H303.B (non-powered signalling devices).

If it’s taped to the glass, G301C says that attaching [an OPERATOR CONSOLE] to the DRIVER STATION is not allowed. A placard/vision target/whatever most likely does NOT count as part of your OPERATOR CONSOLE, whose definition is modified in H402’s blue box stating that “any device connected to the OPERATOR CONSOLE is considered a control device because REFEREES are not expected to differentiate between devices that can or cannot control the ROBOT”. I highly doubt you would get caught under this rule though, it is an incredible reach.

As other users have said, whether it counts as “indirect communication with the ROBOT” is very, very ambiguous. I would again lean towards no, but the HEAD REF would absolutely have the grounds to disallow it.

In my opinion, I would confirm with a HEAD REF before a competition, or on the Q&A board (although you might not get a response because this is a rather specific scenario). Regardless, if you do plan to use this, have a backup plan ready just in case :wink:

Actually, that makes me think of an interesting loophole.

For the sake of argument, suppose that the vision target is affixed to the lid of the laptop, so that it’s not supported in any way by the polycarb. The vision target is then definitely part of the OPERATOR CONSOLE-- which definitely is allowed to control the robot during auton. For example, running vision code on the driver station laptop (getting a video stream from the robot, and then pushing the results back to the robot) is, AFAIK, totally legal.

In this case, then, it’s definitely just the OPERATOR CONSOLE, not the DRIVE TEAM, that’s interacting with the robot.


Hi Carlos,
NB: This is a reply to an early post by Carlos. Carlos posted a comment while I was writing this reply so it appears a little out of order.

Yes this was our intention. To place a marker against the glass/polycarb driver station window in a know position (like the bottom corner) This could be just sitting there separately (maybe with a bit of bluetac to keep it in place) or it could be held there with an extension arm from the operator console /driver station that gets put into place during the initial match setup. Either way it would be a static device and not moved during auto (or during the match for that matter).

To me interacting with the robot during auto would be someone wearing pink arm bands and then waving your arms during auto so that the robot camera could detect this and change its decision during auto. This would clearly be in violation of the rules. But this is not what we are contemplating.

Thanks everyone for your opinions, although I’m still not clear if this would be allowed and or not.

To extend this question, if this wasn’t allowed during auto, can anyone see a rule that would not allow this picture to be placed in said position after auto was finished to help the robot localize during the rest of the match.

Have you considered that you’ll be in a different driver station location each match, so this device would essentially be in one of three locations? Seems to me that could hamper plans to use it as a static navigation aid…



Robot code can access current alliance color and driver station position through WPILib’s DriverStation class so it should be trivial to account for differences in driver station position when localizing. Field tolerances might be a bigger issue for this plan? Particularly if the alliance station walls are being moved by robots hitting them while climbing.


This was kind of already done by Team 254 in 2019. Not exactly the same, but similiar.



So after mulling this over I don’t think this violates any rules but definitely is something that I wouldn’t do.

Using this only for auto mitigates a lot of risks however there is a lot that goes on around the field that you do not have control over. We still don’t know the Volunteers shirt color this year, volunteers are allowed to have dyed hair, the outfits worn by MCs and GAs can be anything, plus you never know what random color or shape might result from teams being in the stands together.

The bottom corners of the drivers station are also only a little over 3 feet tall so if you plan on using this during teleop even a non max height defender could block your view.


They mentioned that it’d only be during auto, so G210 would disallow this, no?

To add on to this, a hanger leg obstructs the robot view of some part of four of the lower corners of the Player Stations.
Teach it to look for your team number sign instead :slight_smile:

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You’d set it up during pre-match.

Marker design and probabilistic robot models over deterministic models can deal with all those issues listed above. Firstly I just wanted to know if its legal to place a marker, before I invest too much time into teaching the students all about Bayes filters, Particle Filters and Monte Carlo localisation.

With the pace that FRC is advancing, I’m suspecting within a couple of years there will be a tensor flow blackbox with a 360 camera available for under $500 USD that will tell you your exact pose on the field at any time.
Im guessing 971 are probably close to this already, they had a robot with 6 cameras a few year ago from memory.

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I’m just going to leave this link here: Zebravision 7.0

Video too(sadly, not from our own robot, 2020/2021/etc):

I look forward to the stack lights being ruled illegal.