What would make the LED on the Victor go out?

Hi

I got a problem I’ve not seen before.

As far as I know the LEDs on the Victors should be either blinking, red, orange, or green when powered up right. When we power up this years bot the LEDs all go out and the motors run full-on for about 3 sec, then the system finds itself and everything seems to work right.

Some specs:
4 moter tank drive
default 2 joystick control
2 right motors on PWM 1 and 3
2 left motors on PWM 2 and 4
only the 4 victors and the controller are powered at this time
???

Matt B

This is probably a question for Innovation First. Did you calibrate the speed controllers? If so did you get a confirmation that the calibration was accepted. See http://www.innovationfirst.com/FIRSTRobotics/pdfs/V883UsersManual.pdf for procedure.
I would next ask if the speed controllers react the same if the robot controller is not powered up when you apply power to the controllers. I was under the impression that the RC was supposed to disable or set to zero all PWM outputs while initializing. If the controllers are normal with no power to the RC, you might have a problem with the RC

Ohh boy!!

I don’t like that answer much.

If I unplug the PWMs the LEDs on the controllers blink just like they are supposed to.

I will try an old RC in the morning.

Matt

Are you using the default program?

Your LED can be off if you are not within the ceritifed “Dead Band.”

Just check your controller, see if it is not calbriated. That may help…

It only goes to Red or Green when it reaches the end of the band (0 or 254)

Thanks for all the help guys.

I really hate to mess with the calibration of the victors. We had a really tough time by doing that 5 years ago and we have left them on the default calibration ever since.

Matt,
All Victors have to be calibrated. If you don’t calibrate, the the victor doesn’t respond correctly to your software and joysticks. It is an easy thing to do. I recommend pulling all breakers except the RC and the controller that your are calibrating when you follow the procedure. (This is a safety thing for me.)
This year more than ever calibrating controllers is important. Since there is no joystick to read and convert during autonomous mode, the controller needs to know what full scale forward and reverse is.

P.S. The controller stores all the values you calibrate when you release the cal button. You have to hold it down until calibration is complete.

My team experienced a similar problem in that when we powered on, the robot took off. Backwards. At full speed. It turns out that we had not initialized the motor variable to 127 in the program. This means that it defaulted to 0, which translates to full backwards. Now, if you didn’t have the victor calibrated properly, it is conceivable that the full reverse light wouldn’t come on, and you would continue going backwards until someone played with the controls… just a thought…

You haven’t had to calibrate the speed controllers for years. The victors (883/884) are precalibrated for the FIRST control system. Read the Victor 883/884 user’s manual

PS. I’m suprised Joe Johnson hasn’t said that yet :wink:

Would you want to depend on the Victor being calibrated from the factory or would you want to be absolutely sure that the Victors were calibrated to your software and joysticks? For a minute of work, a season of good ops.