Router Connectivity Poor

[Hebrew]

Hi,

When we are running our robot wirelessly we continuously run into issues with the router (in AP mode) connecting with the CRio at an efficient pace. (The CRio is connected to the router via ethernet cord) When we push forward the joystick it takes a few seconds for the robot to respond and it keeps losing connection. The wireless card is the only card not disabled and it is only connected to our router. We are running an ethernet cable from Port 2 into the CRio through the router in AP mode.

Are we doing something wrong?

Are there any possible fixes to stop the robot from losing communication?


Thanks.

[Alan Anderson]

While control lag can be due to wireless communication problems, it usually is caused by the program on the cRIO trying to do too much. If you can rule out intereference from other wireless networks, I suggest that you focus on the programming.

[Hebrew]

The program that I was using was the default one for testing wirelessly.

[Cuog]

Try pinging your crio to see what sort of lag you're getting. If its particularly high, you may have a damaged cat5 cable, or router. If you have consistently low response times from the ping test you likely have a software issues either in the driver station or on the robot.

[Keyreaper]

Also try making sure your cRIO, Driver Station, and LabView are all updated to the most recent version. We had a cRIO that was causing lag, but after updating it to match the proper versions of the other software it ran with much less lag.

To ensure that it is in fact the radio or router, try running code directly tethered to the cRIO. And see if the problem still persists.

[DonRotolo]

Also remember that the thingus on the robot is really a radio. If it is mounted near metal, it will be unhappy.

[Hebrew]

Originally Posted by DonRotolo

Also remember that the thingus on the robot is really a radio. If it is mounted near metal, it will be unhappy.

That might have been a reason..it is going to be mounted on a 1/4 to 1/8 inch chunk of aluminum and that was what it was on when it was being tested.

The robot was running fine with an ethernet cable to port 2 of the router and port 3 to the CRio.

I will try pinging the CRio on monday.

I also have not updated to the January 23rd update yet which is what I will also try but I thought it was only for the Axis Camera and imaging the CRio, unless that is related somehow.

Thanks.

[Greg McKaskle]

Especially if using LV, be sure to click to the Diagnostics tab of the DS and see if there are errors. Errors drastically slow the cRIO and will cause lag. Finally, be sure to click to the Charts tab of the DS and see what the CPU, round trip time, and dropped packets are. Those measurements will help us to guess at what is causing the lag.

Greg McKaskle

[Hebrew]

The only error I can remember is the axis camera is not found because we do not have it set up yet.

[dakaufma]

Originally Posted by Hebrew

The only error I can remember is the axis camera is not found because we do not have it set up yet.

Any unhandled error can slow down your code; if the camera isn't connected/configured (even temporarily) you should disable it in the Begin and Vision VIs. That being said, if your code is working properly with a wired connection then this isn't your main problem.

[cgmv123]

Originally Posted by DonRotolo

Also remember that the thingus on the robot is really a radio. If it is mounted near metal, it will be unhappy.

And noise generating electronics. OK, they have metal in them, but they are a lot worse when it comes to radio signals. My portable radio has terrible reception near the electronics hub/frame/terminus room at my school.

[slibert]

We had a similar problem - until we read the rule that says the router on the robot has to receive power from the REGULATED 12v power supply on the power distribution board. If using the unregulated 12V outputs, the router resets when battery load gets high because voltage drops below the 12-to-5V convertors operating min voltage of 10V....