<R31> Experienced Opinions Needed

<R31>: No devices or decorations are permitted on the robot that are intended to jam or interfere with the operation of the vision system (i.e. changing robot color to confuse opponent’s vision system).

This is my first post on the CD board (and this is my rookie year), so I apologize if I am repeating an old topic. I searched as best I could with the limited time that I have to try and answer my question before posting.

I was able to find some old threads from prior seasons that discussed this topic, but they seemed more like speculation than a definite answer. So, I’m hoping somebody will respond, “We tried this last year and didn’t get disqualified…” or “We tried this last year and it WAS against the rules…” or something along those lines.

Our team is considering mounting a couple of the green cathode tubes to the front upper portion of the robot, so that while on defense, this light will distract or confuse the opposing team’s shooters.

My initial reaction was that this was in clear violation of Rule 31. But the more I think about it, the more I wonder: what is meant by “jam or interfere with the operation…”?

Upon further reflection, I believe the function (or operation) of the camera is to lock onto a green light source. The aforementioned strategy would not prevent the camera from performing this operation. It would still lock onto a green light source. It just may not be the correct one.

If a robot had a device that would somehow scratch the lens, or detonate an EMP, then those would definitely be interfering or jamming with the operation of the vision system, and would be in clear violation of R31.

What if there was a really short shooter, and a taller robot drove in front of it. Would that be considered interfering? It definitely would have prevented the vision system from locking onto a target.

I’m not trying to devalue GP. I just want to understand the application of the rule, and how it has been enforced in previous competitions.

I can tell you from an engineering / military perspective, there is radio jamming equipment that is used on the battlefield, that puts out strong radio energy on frequencies known to be used by the enemy.

The effect is the radios lock onto the jammer’s signal, instead of the signal the operator wants to listen to.

Your intended application sounds pretty much the same. If you stop the opponents robot from being able to scan for the goal light (by using a light of the same color, or by firing a laser into its camera) if that is not ‘jamming’, then what is?

its definitely interfering with the intended function of the camera system.

This is illegal. The intent of the game designers is to allow the robot to use the field light source as part of its function. Any other light source will “jam or interfere with operation”.

I beleive this was also answered in the Q&A.

GP is a big part of our game.

I can understand your logic that technically the offensive robot could lock onto either target. However, there’s more to R31 than just jamming and interfering. There’s an example given to allow you to understand the intent of the rule. It says you’re not allowed to confuse the opponent’s vision system. Having two lighted targets on the field is confusing. Therefore, your device would be intended to confuse the vision system; making it illegal.

For the definitive answer, see the Q&A:


Q: We are wondering if we can put the green flowlighting on our robot so that the oppenents robot will aim at us oppesed to the target.

A: No, that would not be allowed

The cathodes would be no different from green flowlighting, really. So It’s quite definitely illegal.

I agree with what everyone else posted. This is how my team thinks about it: How would you feel if it happened to your team?

We actually discussed this at a meeting, MOE (365) paints their robot neon green ever year. We decided that they are probably NOT going to be allowed to paint it this year (at least not green) because it would interfere with the function of the camera.

To me, it sounds like you are trying to deceive the other team, that’s not the spirit of GP at all. At least, not what I’ve learned it to be. Now, driving in front of another robot, that’s just defense. It’s not technically preventing the accurate function of the camera. If the robot moved over an inch, it would see the green light again.

I say no, I think a green neon tube would be illegal.

It will not pass my inspection. Period.

2004, 2005, 2006
Lead Robot Inspector

Thank you for the quick responses!

Part of the advantage in switching to an illuminated light source is that it will help the problems with the camera locking on to non-illuminated green objects. Last year in Philadelphia, our robot’s camera locked dead onto MOE’s fluorescent green t-shirts. I can only imagine what would happen if someone’s autonomous routine decided MOE was the goal. :stuck_out_tongue:

Green light? Why not be more devious and put a UV strobe on your bot. UV drives the camera crazy. Of course there is the counter measure. UV blocking polarized lens. Before you Know it we will have battle bots. Our team is going to try something along the line of track them and PUSH them.

Then the alliance flashing LEDs are illegal? I think not. Obviously, it’s bright green, or lights with a strong green component that would cause a jamming. The camera/programming should be able to ignore anything else.

Yes, you can program the camera to avoid other colors, but intentional addition (other than what FIRST gave you) seems to me to be illegal. I just think it’s inappropriate to even WANT someone else’s camera to malfunction.

Think about how much time and effort your team has put into programming their camera algorithm and routine? Would you wish the same consequences on your own team?
This is one of the ways we teach new students about Gracious Professionalism.
You have spent your six weeks working on the robot, trials, tribulations, etc. Now you get to the competition and see someone else who has spent JUST as much time, just as much effort, fail because of something YOU did wrong. Would you help them?

The obvious answer should be yes, and if it IS yes, then why would you create something to break/cause a malfunction in something else?

In this case, it is entirely illegal by the rules. But I am reminded of the moral argument of tipping. If a bot has a severe COG problem and a spot that flips them over every time… do you push them down? (Not talking about wedges nor a bot designed to tip others)

No. And I would pull our driver if (s)he exploited that weakness.

Actually, last year a vision target was green, much closer to the ground, and was painted. Moes bot still had some green:

This year, i dont see why it would be different, because the light is in the air, and its an actual light, not paint. Plus, you can always limit your camera from looking at the ground

MOE recently tested the camera with a team shirt, and the camera did NOT pick up on it. The shirt was put right next to the light, in various positions, and the camera immediately went straight to the light each time.

As you have seen, the consensus is the green light would be illegal. But attacking this from a different direction, the green tubes are very fragile and would likely break if placed on a robot. If another robot is designed to seek out and shoot at a green light, than you are inviting a lot of balls to be shot at your robot, possibly disabling or damaging your bot or again, breaking the light. Finally, a team with that range on their camera could simply put a shade in front of the camera to have it “see” only green lights above a certain height thereby eliminating your strategy completely. As you can see, fully thinking through the problem will yield reasons against particular strategies even when they are legal. It is what most teams will do during the design process to get to the best design they can. Prototyping helps as well.
You are not the first rookie to come up with ideas that go against the mainstream or violate the rule book so don’t feel bad. Thanks for getting this clarification before ship where eventually an inspector would have the distasteful task of asking you to remove it. Ask anything anytime.

Good to hear! Moe always seems to be ontop of things like this. I guess that light is just too good of a target! Hope you didnet mind me using you as an example. :smiley:

This depends hugely on how the camera was configured! I’ve seen your shirts before (very hard to miss) at capital clash, and I think you may have problems if your drivers were wearing them. That said, programmers should really be ignoring things below a reasonable height.

that is the problem. To get the maximum triangulation on the light the camera needs to be at floor level, looking up at an angle (if you want the camera to measure distance + direction to target).

The program assumes the light is at the proper height. If it locks onto something else, the decoy could be at any height, and the tracking system would have no way of telling the difference.