CANBus Jaguars don't Respond to Motor Commands

[sleepisforthewe]

Hey guys,

  I was surprised I didn't see any examples of this, but thought it must be pretty simple. I'm attempting to command a Jaguar over CANBus with a simple VI. I am able to read all parameters I want from any Jaguar I want, but when I command the Jaguar to move under PercentVBus mode (or any other mode for that matter), nothing happens.

The yellow light is also steady on the Jaguar I'm talking to. I have Enabled the robot on the Driver Station and added a simple PWM motor as well to prove outputs work. I figure I must just be missing some simple block to enable final output or something... You'll see I've added all kinds of likely unessesary VIs as well trying to debug. Any ideas?

Thanks,

-Mike C.-

Team 1444

[sciencewhiz]

Can you control the controllers with BDC-COMM?

There are several CAN examples. Tutorial 9 on the LabVIEW getting started screen is CAN. In the FRC Examples in the LabVIEW example finder there are 5 CAN examples.

[sleepisforthewe]

Thanks for the reply.

Yes the motors run in open-loop voltage control from BDC-COMM just fine. Hah, I just found the CAN examples under "Find FRC Examples" link from the start screen. The only difference between theirs and mine I see is that they don't use the "Enable" motor VI. Tomorrow I'll try their example and mine with the Enable removed. We'll see...

[DAQjr]

Look for any errors on the Driver Station in the diagnostics tab.

You may also look on the NetConsole for any messages (remember it has to be enabled in the imaging tool).

[sleepisforthewe · Accepted solution]

Yep, deleting the "Enable" VI caused it to immediately work. Naturally it was one of those 30sec fixes that took 6hrs to discover. I got the idea from the FRC CAN Jaguar example VI. I finally found it last night after using the "Find FRC Examples" on the Labview Launch Screen under Support. Thanks for your input guys. Time to try some fancy stuff...

My theory on why is that the Enable VI enables the Jaguar's internal PID controller. So when in Open-Loop modes and without any PID parameters, the Drive won't have any output.

-Mike C.-

Team 1444