Communication between several Lego Bricks within a single robot

Hi,

Is the use of several Lego Bricks* within a single robot allowed, and which modes of communication between bricks are legitimate?
*(generalizing NXT, EV3, SPIKE as “brick” for this)

  1. Wired connections
    Some bricks can be daisy-chained with a wired connection - according to some past forum posts this is OK, and nothing else than using different circuit boards in one robot. I have also applied this interpretation for one team in this year’s Austrian Open already.
    Is this interpretation still correct?

  2. Wireless connections
    The general rules state that:

Robots are not allowed to use any kind of communication during game play unless the communication between two robots is via Bluetooth class 2 or class 3 (range shorter than 20 meters) or via ZigBee.

I’ve found conflicting interpretations in past forum posts, asserting either that this means communication within a single robot is just not allowed at all, or that it is fine if following the rule.

Personally, I can also see this rule just not applying at all for a single robot with 1 to N Lego bricks (or RaspberryPis, Arduinos, …) just being components within the same robot and there being no current restrictions on how components within one robot communicate.

I was asked this question by a team who qualified for the European and World Cup events at the Austrian Open, and would appreciate it if we could give a general answer to this.
(Possibly even adding some clarifying wording to future 2024 rules)

Thanks in advance!
Cheers,
Nico
RobocupJunior Austria

Hi @Nico ,

Thank you for your question, this definitely started a conversation in the committee to see how we can improve the rules for 2024 :slight_smile:

Is the use of several Lego Bricks within a single robot allowed?*
Yes, having more than one “brain” it’s allowed. This can be a combination of bricks (like 2 LEGO bricks), with multiple brands or types (1 brick with 1 arduino).

which modes of communication between bricks are legitimate?
1. Wired connections
You’re correct, all wired connections within a robot are allowed. All the wires required to connect the “brains” are considered part of the robot.

2. Wireless connections
The intention of that rule was to simplify other competitions where they require multiple robots, like RCJ Soccer and RCJ OnStage. In the scenario of RCJ Rescue, it is there to provide a valid wireless way of communication with other teams during the super team competitions.

Now, considering the ambiguity of the rules and after discussing this with the committee members, we determined that for now we will be accepting wireless communication between the same robot components with the previously mentioned protocols. We recommend teams to do not opt for this option as we cannot guarantee that the wireless communications will work great in the competition arena and/or there will be a “safe” connection guarantee for these protocols (for example, a malicious spectator trying to connect to unsafe bluetooth ports to cause performance issues in the robot). We will be working into making better changes in the 2024 rules for this case.

Thank you!

Diego Garza Rodriguez
2023 Committee

1 Like

Hello @Dieguinilombrin

I read “Rescue Line 2023 rules” and “Rescue Maze 2023 rules”.
RCJRescueLine2023Rules.pdf (Last updated: 2023-05-21)
RCJRescueMaze2023Rules.pdf (Last updated: 2023-05-21)

Rescue Line
3.2.4. Wireless communication must be used as described on the RoboCupJunior General Rules.

Rescue Maze
3.2.6. Wireless communication must be used as described on the RoboCupJunior General Rules.

These rules have not changed, nor have the RoboCupJunior General Rules.

your answer

we determined that for now we will be accepting wireless communication between the same robot components with the previously mentioned protocols.
We will be working into making better changes in the 2024 rules for this case.

Is this already allowed?
or, Are you saying that permission will be considered under the 2024 rules?

Regards,
MASA

Hello @MASA ,

Considering that now it’s the moment I made the post, yes, this is allowed in the 2023 competition and we can reference this post as reference for any possible clarifications needed. We will formally incorporate the changes in the 2024 rules.

Thanks,

Diego Garza Rodriguez
2023 Committee

Hello @Dieguinilombrin

Thank you reply

yes, this is allowed in the 2023 competition and we can reference this post as reference for any possible clarifications needed. We will formally incorporate the changes in the 2024 rules.

I understand.
I hope this will be specifically described in the 2024 rules.

Regards,
MASA

Hello
I read Rescue Line 2024 Rules (DRAFT). RCJRescueLine2024RulesDraft.pdf

@Dieguinilombrin write

we can reference this post as reference for any possible clarifications needed. We will formally incorporate the changes in the 2024 rules.

Section 3.2.4 describes the use of wireless communications. but nothing has changed from the 2023 rules.

we determined that for now we will be accepting wireless communication between the same robot components with the previously mentioned protocols.

Is this communication still allowed?
Will the changes be reflected in the final version of the 2024 rules?

Regards,
MASA

Hi @MASA ,

Thanks for bringing this to our attention. We updated the 2024 draft rules and will be posted in the official release. This is going to be the new rule for both line and maze:

3.2.4 Wireless communication is only allowed for the SuperTeam Challenge and must be used as described on the RoboCupJunior General Rules – RoboCupJunior[RoboCupJunior General Rules]. Robots performing other types of wireless communication need to be deleted or disabled. If the robot has other wireless communication equipment or is on a game different than the SuperTeam Challege, the team must prove the wireless communication is disabled. Non-conforming robots may be immediately disqualified from the tournament.

Let me know if you have any questions with these changes.

Diego Garza Rodriguez
2024 Committee

Hello @Dieguinilombrin

Thank you reply.

3.2.4 Wireless communication is only allowed for the SuperTeam Challenge

I understand that the “final rules” will change.

you wrote before

we determined that for now we will be accepting wireless communication between the same robot components with the previously mentioned protocols.

This communication, which was allowed in 2023, will not be allowed in 2024.
is my understanding correct?

Regards,
MASA

Hi @MASA ,

You are correct. The wireless communication that was previously accepted for 2023 won’t be accepted in 2024 outside of the SuperTeam Challenge. This includes wireless communication within the same robot.

Thanks,

Diego Garza Rodriguez
2024 Committee