HELP!!! Calibrating Victors

[comwiz7]

We are in dire need of some help regarding the calibration of the victors. We have them attached to one of the CIM motors we will be using in the KIT transmission. We pulled the motor out of the transmission so it doesn't conflict with the other motor.
When we go through the calibration process we get an unsuccessful (red light blinking) calibration each time. We have tried to reset the victors to factory calibration but we have the same problem. We also can't seem to find the dead zone on the joystick.

[SpaceOsc]

Originally Posted by comwiz7

We are in dire need of some help regarding the calibration of the victors. We have them attached to one of the CIM motors we will be using in the KIT transmission. We pulled the motor out of the transmission so it doesn't conflict with the other motor.
When we go through the calibration process we get an unsuccessful (red light blinking) calibration each time. We have tried to reset the victors to factory calibration but we have the same problem. We also can't seem to find the dead zone on the joystick.

I deal with this on daily basis now during the season.

1. Download the FRC Dashboard Viewer www.ifirobotics.com/dashboard_viewer.shtml

2. Use the Dashboard Program to physically calibrate the Joysticks to 127 (Center).. try to keep it from moving to 126 to 128. if u cant its ok as long as it hits 127 at some point. this read out will tell you when your joysticks are actually centered. Be aware that the joysticks from FIRST (White ones) almost never center on their own.

3. Make sure your Victors are fully complimented with the corresponding programming, Correct Pwm ports to correct Joysticks, and all power cables to each victor.

4. ideally a two man Job, With everything on get a small pin to reach the pushdown button and press the victor calibrate button and hold it down. IMPORTANT!!! do not move the Joysticks at all before or during the act of Pressing the Calibrate Button. Press the Button and once the LED flashes around tell the guy at the joysticks to move all the way up and all the way down about 3-4 times (doesn't really matter) tell him when to stop and until he is centered again you finally let go and hopefully you will get green.

5. Doing it in order and observantly will increase the chances of calibrating correctly

Hope it helps

[comwiz7]

Thanks for the tips! I'm going to try your suggestions tomorrow first thing.

[sparkydp]

another thing to check is if you're using a joystick that has manual sliders on the side for calibration, if those are too far out of alignment, the victor won't get a full range of values. It's sometimes to handy to have the RC just printout the pos(x,y) of the joystick so you can make sure it travels from 0 to 254 in both axis.

[Al Skierkiewicz]

Com,
There is no real reason to pull motors to calibrate. Just remove the breakers for the other motors during the procedure. It is also possible your PWM cable may be intermittant. Try changing it, they have been known to be bad in the past.

[phrontist]

I see the general concensus seems to be that one should calibrate the victors by pushing a joystick to the extremes. Wouldn't it be better to send pure 255 and 0 signals in code?

[Al Skierkiewicz]

Originally Posted by phrontist

I see the general concensus seems to be that one should calibrate the victors by pushing a joystick to the extremes. Wouldn't it be better to send pure 255 and 0 signals in code?

That would be fine if your joystick to A/D interface were perfect. In this case you are telling the speed controller "no matter what you think or what someone else told you, this is full forward and this is full reverse and this is me letting go of the joystick, now remember that and we will be fine."

[Alan Anderson]

Originally Posted by phrontist

I see the general concensus seems to be that one should calibrate the victors by pushing a joystick to the extremes. Wouldn't it be better to send pure 255 and 0 signals in code?

254. Not 255. Get in the habit of considering 255 an illegal value for both joystick input and pwm control.

If you're going to "calibrate" a Victor by sending it full-scale signals, you're not really calibrating it to your operator inputs. You'd have an easier time resetting it to its default calibration, and you'd still want to be accommodating the range of values you get from your joysticks in some other way.

[kaszeta]

Originally Posted by SpaceOsc

I deal with this on daily basis now during the season.
3. Make sure your Victors are fully complimented with the corresponding programming, Correct Pwm ports to correct Joysticks, and all power cables to each victor.

Note that since many teams do a lot of code between the joysticks and the victors (deadbands, scaling factors, etc), it's worth writing a program for your bot that does nothing but calibrate the Victors. Our team wrote one that automatically ramps all the pwm outputs between 0 and 254 unless a joystick button is pressed, at which point it drives all the pwms to 127. Very useful for calibrating.

Of course, if you didn't do anything to the Victors in the first place, they won't need this.

And if you are directly tying your operator inputs to the Victors, then the listed procedure with the joystick is defintely the way to go.

[Joe Ross]

Originally Posted by kaszeta

Note that since many teams do a lot of code between the joysticks and the victors (deadbands, scaling factors, etc), it's worth writing a program for your bot that does nothing but calibrate the Victors. Our team wrote one that automatically ramps all the pwm outputs between 0 and 254 unless a joystick button is pressed, at which point it drives all the pwms to 127. Very useful for calibrating.

What's the purpose of doing that compared to reseting to factory calibration?

[sparkydp]

the biggest reason to calibrate is to take into account the imperfection of your joystick, using the code to calibrate will make sure the victors accomodate the whole range of values, but then there is no guarantee that you're sending that to them using your input from the joystick.

[comwiz7]

Thanks everybody for your tips. The dashboard program really helped us a lot, I can't believe I didn't already know about it.

[SpaceOsc]

Originally Posted by comwiz7

Thanks everybody for your tips. The dashboard program really helped us a lot, I can't believe I didn't already know about it.

So it all worked out? Glad to hear it