Answered: Motors overloading or Cortex turning off

I am building an arm out of vex for the Science Olympiad. It isn’t too heavy, and sometimes, when my cortex does not do something weird, one of the two 393’s that I have connected to turntables is able to begin lifting it before it glitches. When I try to make them lift the arm, it starts to go up, but then the lights on the cortex go blank, then come back on and start blinking yellow trying to reestablish a connection with the joystick. I have updated to the newest Master Keys yesterday so I know that isn’t the problem. I can attach a video or picture if that would help.

roboinventor,

Can you duplicate the issue while controlling your robot directly connected to the Joystick with the USB A-to-A cable?

-Eli

No, the motors work perfectly when I plug it in, but is there any way I can make it work wirelessly?

roboinventor,

The issue that you are experiencing may be cause by a damaged VEXnet Key.
Do you have a different set of keys you can try?

Also try our newest Master Code, as it features a more robust VEXnet link.
Let me know if you need help upgrading to the newest Master Code.

-Eli

I tried my friends keys and it had the same problem. I just got my vex recently and I also got easyC v4 with it. A couple of days ago I upgraded the Master Code, do I need to see if EasyC needs to update before I update the code?

Yes, please make sure you are running the latest version of easyC.
Click on “Help” and then “Check for Updates”

-Eli

It says that EasyC is up to date and I plugged my cortex and controller into the computer and checked that the master code is up to date.

Excellent.
Now take a look at your batteries.
On the Cortex:
Are you using AA batteries or one of our 7.2V VEX battery packs?
Also make sure that you have a secure connection between battery and Cortex.

On the Joystick:
Make sure you are using fully charged AAA batteries.
If available, power the Joystick with our VEXnet Joystick Power Adapter.

-Eli

Right now I am using AA batteries in the Cortex and brand new AAA’s in the joystick. I think the AA’s should be in good shape because I only put them in a couple of weeks ago but I can try to get new batteries for it.

roboinventor,

Since we are trying to isolate the problem, please try a different set of batteries on the Cortex and Joystick.
If you do not have a different set of batteries, try using a Voltmeter to measure the voltage across your battery case.

-Eli

I put new batteries in the cortex because I had already had the problem last night and replaced the batteries in the Joystick. The motors will last longer now but the cortex still cuts out. I can now get about 8 seconds of continuous work before they stop.

I replaced the batteries and it lasts longer, but it still cuts out. Now it will last around 6 seconds before they stop.

**If everything works when the Cortex and Joystick are connected via the USB A-A Cable, then you have a VEXnet Link issue. Please verify again everything works ok when Tether with the USB A-A Cable. If so, then try the following:

Since you have already tried a known “good” set of VEXnet Keys, you may be in an area where there is too much WiFi traffic. Trying turning Off all Wifi Transmitters in the area or try the robot in a different area – your house, school, a parking lot……

Another possibility is that you have too much metal around the VEXnet Keys – too much metal can cause interference preventing the VEXnet signals getting to and from the VEXnet Keys. Try removing some metal and try moving the Joystick very close to the Cortex.**