as far as I know the Raspberry Pi was never forbidden, it was not only added last year.
I understand your concern, and this is indeed a problem. One option would be to just completely forbid any kind of wireless communication. But if we do this, teams could not use LEGO MINDSTORMS or most Raspberry Pis anymore. Some teams use multiple MINDSTORMS on one robot and let them communicate via Bluetooth - this would not be possible anymore then.
First of all we trust the participants to play by the rules - the rules are very clear about remote controlling robots. If we notice this, the team will be disqualified.
Apart from that we are going to conduct interviews, just like the last years, where we will inspect the students robots and software. Students need to be able to explain what their robot is doing in which situation. If they can't do it, this is very suspicious and a good sign of a) either the students didn't built their robot or b) the robot is remote controlled.
The judges will be instructed to write down suspicious activities if there are some. Based on that interviews will be executed in depth.
I always recommend teams to just remove or disable their wireless devices if they can - this way it is not possible that there are any interferences, either randomly (since there will be many persons walking around with their phones enabled) or on purpose by other teams. If there are any doubts you are on the safe side then.
We think that these measures are sufficient - at least we made good experiences with them in the last year.
If you have any suggestions about how to improve the process, please let us know!
We are looking forward to a fair competition!
Rescue OC Montreal 2018