Wireless Connection Issues

Hello! This week we ran our first ever VEX IQ camp at our local community college. We had 10 new Super Kits for the kids to use. We had a ton of connection issues with the IQ kits this week. Monday and Tuesday, they worked fine, ran them all day, no issues at all. Wednesday and Thursday, the brains/controllers kept dropping connection. We tried reinstalling the firmware, different/new controllers, brains, tethers, data wires, charged batteries, static spray, etc. and at one time, all 6 bots had to be tethered just to drive. Most bots will last about 30 seconds then drop connection. Not sure if this is a known problem with the new firmware but again, it was fine earlier in the week.

It worked better today once we found an issue with versions of the firmware. All computers had RobotC 4.10. My computer had a build date of June 11th, the others, June 4th (although when you clicked to check for updates on the June 4th computers, RobotC said it was up to date). I uninstalled the June 4th build date and installed the June 11th. 3 of the 6 worked fine (90-100% reliable) 2 ran well about half the time, and 1 we had to put a Modkit driver program on it before it would work. All autonomous and tethered driver programs worked fine. I remember having these issues last year related to the I2C problem (tethered and auto programs ran fine, wireless would cut out with these errors). We have ni I2C errors, but the pattern seems to eerily similar. Any ideas?

Thanks!

Hi trianglerobotics,

We’re very sorry that you have encountered this problem. To help us diagnose and fix this problem, can you provide us with some additional information?

  1. Are you using the 900 MHz Radio or 2.4 GHz Radio?

  2. When the Robot Brains and Controllers are turned on, what radio channel are they using?

This channel information can be found by pressing the X button on the Robot Brain when on the Home Screen to access Settings. Then press the Down button to highlight System Info, then press the Check button to access those settings. Press the Down button to change from Robot Brain to Controller. When on the Controller screen, the final line lists “Channel” and then a number.

The channel should be unique for every Robot Brain that is on in that room, and the Channel will likely be different every time the Robot Brain is turned on.

Regards,

  • Art
    Tracks 007.jpg

Thanks Art, I will try them when we begin our next camp on Monday and let you know.

Greetings Art, the radios are 900Mhz and when we check the channels, they are different. In our first run today, they worked fine. The second run, the one stopped as soon as the other was connected. When this was going on, one team would get a message “connect controller” when they had been driving fine (just came out of the blue when the other team connected theirs). We noticed in the settings that the strength is only about 50%. If any thing comes between them, it shoots down to less than 10.

We are getting a ton of “connect controller” messages now after 5-10 seconds of driving.

Hi trianglerobotics,

We are currently investigating this issue here in further detail as we have not seen this level of communication issues before. To help resolve this situation, please check your building area for any older cordless telephones or similar wireless radio devices that may be causing radio interference. Some older cordless telephone systems from the 1990s used the 900 MHz radio spectrum for communication between the handset and the charging/base station (almost all new ones have switched to 2.4 GHz spectrum).

If you look on the label on the bottom of these products it will say what radio frequency it runs at. If you see any running on the 900 MHz spectrum please temporarily disable or turn them off to see if the issues with VEX IQ radio communication improve.

Edit:
If you cannot find any obvious sources of other devices running on the 900 MHz radio spectrum, there may also be less obvious sources of radio interference. To help out all potential for radio interference problems, please take the VEX IQ Robot Brains and Controllers to a more remote location, like the end of the parking lot or the middle of the sports fields at your school and test them there. If everything works well in this remote location, then it is likely that another 900 MHz device is causing interference with the VEX IQ system in your classroom/build area.

Regards,

  • Art

Thanks Art, I will take a bot home and try it there. Could the fact that the building we are in has as many as 9 wireless networks being recognized by computers cause this interference?

Art, I believe the issue is in the 1.11 IQ Firmware. Late last week, we put a sample driver on all the robots from a computer that was still running 1.10 (offline-so no auto update). We did not have any issues. Today, all students opened IQ Firmware Updater and installed 1.11 and began having the connection issues inside of 15 seconds. We went back, put on 1.10 and it worked fine for multiple hours. In both instances, we were running RobotC firmware 4.10 (build date June 4th) so that remained constant in both cases. That’s why I think it’s with IQ Firmware 1.11.

Hi trianglerobotics,

Please contact VEX Technical Support by emailing support@vex.com or calling us at 1-903-453-0802 so we can provide more detailed assistance to resolve this problem.

Regards,

  • Art