Rescue Line 3.2.8 Rescue Maze 3.2.10 esingle binary switch

I read “RoboCupJunior Rescue Line Rules 2023”. (RCJRescueLine2023RulesFinal.pdf)
and I read “RoboCupJunior Rescue Maze Rules 2023”. (RCJRescueMaze2023RulesFinal.pdf)
so I have some questions.

Rescue Line
3.2.8 Robots must be equipped with a single binary switch or button of any kind, clearly visible to the >referee, for restarting the robot when a lack of progress occurs.

Rescue Maze
3.2.10 Robots must be equipped with a single binary switch or button, clearly visible to the referee, >for restarting the robot when a lack of progress occurs.

Q.1 Can only one switch be operated during LOP?

Q.2 The Lego mindstorms EV3 has two switches (stop button and start button) and the following article allows the use of EV3.
Is this still allowed for EV3 use?

Q.3 Are the operations described below allowed when LOP?
The robot has two switches (power switch and reset switch)
Robot Stop : Power switch → off
Robot Restart : Power switch → on and Reset switch → one push

Q.4 The same operation is required at every LOP. correct?
The rules don’t say that.


Hello MASA,

The objective of this rule is to make sure there is a consistent way of restarting your robot when there is a Lack of Progress. Being clearly visible allows the referees understand that the robot is going through a LoP and no extra information is being provided (some examples are premapping, informing to change left/right priority, letting the robot there is an obstacle, if there is a rescue kit in place, changing programs, etc). Now with this in mind, let me answer your questions.

Q.1 - Correct.

Q.2 - As the thread indicates, EV3 is a platform where there is a limit to the number of sensors that can easily be attached, therefore we allow to use the buttons include in the EV3 if the brick is clearly visible to the judge and the sequence you describe is always the same, not changing programs. EV3 is still allowed. In this case, I recommend the team indicate to the referees how the system is going to be restarted and make it as clear as possible to follow the same mechanism in from of them when a LoP occurs.

Q.3 If your robot is using a microcontroller or similar where you can add multiple sensors, I will recommend not opting for this set of operations. If your robot design only works with this sequence it will need to be explicitly call out to the referees beforehand and make it easily identificable to make sure the order is not altered (for example, both switches clearly visible, marked with different colors, showing that a different order doesn’t do anything, etc). If the judge believes a different sequence was followed (intentionally or unintentionally) that can be enough to be consider a penalization. In conclusion, is better if there is only one binary switch to be operated during a LoP.

Q.4 You’re correct, it is stated in the rule 4.5.3 “After a lack of progress, the team must reset the robot by using a switch located in a visible location by the referee (see 3.2.10).”

Let me know if you still have any questions about this or the specific implementation for your robot.


Diego Garza Rodriguez
2023 Committee

Hello @Dieguinilombrin

Thank you reply.

Answer of Q.2
LEGO EV3 can be used in competition.

Answer of Q.4
We must to do the same operation every LOP When LOP occurs.

I understand.

Please teach me about Q.1 and Q.3 again.
your answer is
Q.1 Only one switch can be used in LOP
Q.3 Two switches can be used in LOP
These two answers don’t seem to match.

A robot with one switch is recommended.
Although not recommended, robots with multiple switches can participate in the competition.
do you mean this?