Communication Issues from EMI?

[BB3539]

Tell me what you think ...

We kept losing communication when the robot was running. After checking every connection, and replacing every component we were perplexed and frustrated. Looking at it and thinking about telecommunications, could this be the solution? Now, call me crazy, but having our radio sandwiched between 4 CIMs and 2 Mini CIMs (see image below) would put it right into an series of magnetic fields. The motors are designed to concentrate the field inside, but I would believe there is still fields generated outwards from the motors. Given all the changes in drive direction, those fields were constantly changing and irregular. So, we moved the radio out away from the CIMs/MiniCIMs and presto, no more communication issues.

Crazy or good scientific solution? Please let us know if we are way off here, or if this logic makes sense.

[Mark McLeod]

That's a definite cause.
We want to keep the radio some distance from all electromagnetic noise sources.

We also want to keep it from too much metal that would interfere/block with the internal antennas, i.e., the metal mass of the CIMs.
Don't bury it in the bowels of the robot, keep it up in the clear.

Avoid even mounting it on a vertical metal plate that would mask it. A Lexan/pvc or other non-conducting/non-metallic mount is preferred.

[rich2202]

Radio should be high on the robot. That would put it some distance from the drive cims.

[GeeTwo]

That long loop of cable makes a great antenna; we have a very short cable between the two.

[BB3539]

Thanks for the tips and info!

[mac]

If and I say if. All those components were on the bottom. It should have failed inspection. The lights on the radio are suppose to be visible by field personal. FTA, CSA, Head Ref and Field Reset people that know what the deal is. That way your grief would never have come up. Just weak inspections. Thank You, God Bless, Mentor Mac

[rich2202]

Originally Posted by mac

If and I say if. All those components were on the bottom. It should have failed inspection.

There is "fail", and then there is "FAIL". Yes, an RI will cite the team for the problem, but, if there is no way to easily remedy, it is not a deal killer, and eventually allowed to play.

As long as someone can look in and see the lights, then that is fine. If they can't, then the team better make sure they don't have a communications issue, or they may be disabled because the FTA's are not going to spend time in later rounds figuring out if the radio is the problem if they can't see it.

[Al Skierkiewicz]

BB,
If mounted as shown you placed at least one of the antennas in the radio next to a CIM motor. This serves to overload the radio receive input and detune that antennas.
Place radio high and away from metal as best as you can on your design.
Al