2023 Draft Rules Public Discussion #soccer-rules-2023

Hey everybody, we have merged most of the changes into the 2023-draft-rules branch the current version of which automatically gets built to this URL: https://robocupjuniortc.github.io/soccer-rules/2023-draft-rules/rules.pdf

Pending pull requests also get built at https://robocupjuniortc . github. io/soccer-rules/<branch name after the ‘from’/rules.pdf (for example the PR https://github.com/RoboCupJuniorTC/soccer-rules/pull/68 gets built to https://robocupjuniortc.github.io/soccer-rules/aquahika/omnidirectional-lens/rules.pdf)

There are also a couple more changes I added to the first post of this thread:

  • We added ±10% tolerance on the 20mm line width
  • We reflected the reality that lines are frequently not painted but taped or installed as white carpet in the rules
  • Limited maximum voltage anywhere on the robot to 48V safety reasons
  • Introduced communications module for the future

We had an issue using the 2022 rules in lightweight and 1vs1 open about the line
In Lightweight, the robot must not emit infrared light.

This is a clear statement, but it still was subject of many discussions.
As you cannot see IR light, you can only prove that a robot emits IR light by another robot that gets disturbed. Unfortunately some teams changed this clear statement to something like “you have to prove that your robot gets confused by our robot” and that moved the discussion from the inspection-desk to the field and caused discussions (sometimes even arguments) between teams.

So the easiest way would be to stick to this rule and disqualify the IR-Light emitting robot until the IR-light emitting devices are removed (and not called “switched of” by the team).

But on the other hand actual lidar sensors could replace ultrasonic sensors. They are better, cheaper and last longer. So I can understand the desire to use them.

But then we need a rule change.

It is possible to build a IR-detecting ring that can cope with getting IR-laser lights right into the sensor and we could say that good teams should know how to build a proper IR-ring.
But if we have the rule of “no IR at all” just the beginning teams should rely on this and should be fine with the most simple IR-ring possible.

If we want to allow IR-lidars we should make this clear and introduce a rule like “Teams have to be aware of IR-pollution on the field and have to build ball-detectors being capable of this”.

Both would be fine, but please clarify this in advance.
I do not want to see teams arguing with each other on the field instead of having an enjoyable and fair game.

So if we want to stick to the “no-IR” I would suggest the additional line “In Lightweight, the robot must not emit infrared light. IR-emitting devices (including IR-lidars) are not allowed on the robot, even if switched of”. This would bring the discussion about it back to inspection desk where it belongs.

Nevertheless these great lidar sensors should be recommended for 2vs2 open or any other league that does not use the IR-balls.

Best regards

Hey Roland,

Was the team claiming interference using IR receivers or just IR sensors? I’m trying to find out if boards like the popular VL53L0X emit pulses similar to the IR ball’s carrier frequency. Understanding that saturating the field in IR would cause issues even if filtering for ambient IR - I’m wondering if there may be some sort of compromise that IR VSELs could be allowed if mounted at a minimum height (noting that the walls now should now be higher), perpendicular to the field (which is the most likely how it would be used correct?), and be limited in number (e.g. four per team).

It would be great to see if any teams reading this could verify if there are conditions in which lidar can be used and unlikely interfere with other teams detecting the ball.



I agree with widening the field, but am I correct in understanding that the 10cm width of the perimeter means that the out-of-bounds rule only applies to the penalty area? Am I correct?

The current out-of-bounds rule is “if the robot’s entire body goes out beyond the white line of the field,” but if the outer area is reduced from 22 cm to 10 cm, it would be practically impossible for a robot’s body of 18 cm in diameter to go all the way beyond the white line into the outer area.

If the above is correct, I feel that the out-of-bounds strategy would be much easier as it would only need to be within the penalty area.
Under the previous rules, it was easy to do out-of-bounds at high speeds, which also served as a sort of speed limit, but I am concerned that the new rules will lead to higher speeds, especially for LightWeight.

In fact, my impression from the Bangkok tournament was that the out-of-bounce strategy proved to be not easy, as teams with a decent out-of-bounce strategy, both LightWeight and Open, were strong.

This change will have an impact not only on future matches, but also on robot development. In other words, in exchange for the increased difficulty and reduced burden on referees gained by a larger field, will not the difficulty of out-of-bounds strategies be reduced, causing robots to go faster?

Best regards,

I quoted your question and posted a response into the corresponding thread.

@stiebel @Mike I created a discussion thread for the IR emissions/IR detection issue here. Let’s continue the discussion over there.

Thank you! That is what I wanted!

Soccer Open

I disagree with the removal of the limits on the number of cameras and the viewing angle, because I think that limitations stimulate creativity. Furthermore, this is consistent with humanoid soccer, where vision limitations exist. With no limitations, 2 camera with 180 degrees angle of view give omni vision system, this means that it possible to solve the problem buying 2 cameras,
I would like the problems to be solved with ideas.

Hi everyone, I’m Raimondo form Italy, Team MegaHertz mentor, and Italian RR 'til 2021.
I have some point to suggest and I’ll start from Soccer Lightweight

Soccer Lightweight
This sub-league is supposed to be the entry league in the international competitions, but if we observe the international (and also national in my experience) tournament the level is quite higher than open league. I think this is due to the fact that rules in this category was substantially stable for many years. In open league, from 2016 two important rules changes was happened, and thank to this, new teams are allowed to compete with same possiblity than others. In Lightweigt is more difficult to start. In my mentor experience, in the past first with the new students I started in the Lightweight category and then they continued in the Open category. Now I start directly in the Open category, it’s easier and less frustrating because the level allows new teams to play.

Concluding I think that rule changes in the Open sub league worked well, and made international and national tournament more playable (especially for new teams), so I propose to make important rule changes in the Lightweight as well:

  • reduce size to 20cm diameter
  • move to “old” orange passive ball
  • introduce power or torque limitation

I explain my proposal:

  • reducing robot size (like Open league) corresponds to having a proportionally larger field. This should increase use of strategy in game.

  • the pulsed ball is too big for a 20cm robot, so I propose to use 7cm orange passive ball. Furthermore, this make easier the first project, in fact there’s many embedded vision system, but very less pulsed ball detectors, so that in Lightweigt teams have to design their own.

  • in the past rules, we can find “rules aimed to favor skills over brute force in the games” I think we have to follow this direction, and introduce power or torque limitation in this sub-league (for the moment) is the only way to avoid that the game became a money game and not a strategy game. In this moment, use powerful (and expensive) motors ensure performance. But if we want to favor game strategy is the only way, cause field is too small. Power supply limitation is not enough, cause is always possible to get powerful motors if you can spend enough.

Please post this specific point in the camera limitations thread linked above so all arguments can be collected there.

Hi Raimondo,

these are interesting points and suggestions. I opened a separate thread for these here and responded there as well.
I’d like everybody’s experiences there with respect to how hard it is for new teams to get into LWL and OL respectively.

Best Regards

May you help me to find where I have to post?

Soccer Entry

I know that international rules don’t have Entry rules, but in the past some suggestion was given.
As the level in the other sub-leagues is very high, I think we need standardized rules for the Entry League. It is important to have standard rules, to give certainty to the teams. This is important in regional and super-regional tournaments. For example, the year in which there were problems with incorrect publication of the rules in EURCJ. So we need a place where the rules are published without errors, and the site must be stable, if it is not possible to publish on an international site, you can use the super regions sites.
As for the contents, as I said during the RR meeting, I am rather opposed to the constraint linked to brands, but I am instead in favor of technical limitations, as we did in the Italian championship.

@remosgro Please check out the thread started on entry rules discussion here. There is also a news feed thread you may subscribe to here for announcements regarding entry league.

There is an effort to stabilize entry league rules!

We’d particularly love to hear specifics on the regulations around the Italian entry league where @Mike alreadly linked to. We’re trying to get an overview of what Entry leagues are even running and ware going to be trying to get them to harmonize enough for the super-regional competition to not require major changes from teams.

For today’s Open Calls we’re not going to make Entry Rules a major topic of discussion to keep focus on the 2v2 rules draft but right after the regular Rules are finished we’re going to focus on the Entry rules (that’s why there are already forum threads for that).


Hi David,

you can find the 2018 EURCJ version of entry rules, was called “superlight”.


This year we made some small adjustments (move to 9V supply) but I have no EN version.
Anyway the ideas is a LW with some limitations.
The main limitation is that only 2 motion motors must be used, cause omni movement is difficult to implement for the first experience team. You can join this category only once.
We don’t used small field, cause we assumed that school already have the big one, and mentors use this league as preparatory, or as first experience.
If you have questions I’m glad to discuss.

Hi Raimondo,

I went ahead and cross-posted that to this thread which is where we’re trying to collect experiences.

Best Regards

Hey everybody,

the final rules are now finished, nothing much changed over the latest revisions of the draft (except some stuff that went missing in the edit, the replacement out-of-bounds rule wasn’t in yet and other stuff helpfully pointed out during the Open Calls). You can find them at the usual place on the website.

Thank you to everybody who has contributed, we would have made worse rules without you.

Best Regards

Hi everyone,

I hope I’m not spamming you with this, I thought if you were interested in the new rules you might also be interested in the new scheme for the judged awards. @Mike made a detailled description and posted it for discussion in this new thread and we’d appreciate any feedback you may have what makes sense to you, what parts of the description are maybe not as easy to read and understand, if you foresee any loopholes that we should close, stuff like that.

Best Regards