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kDude
02-15-2008, 05:23 PM
We're using a function in our robot's code that lessens the sensitivity of the analog sticks. But now when we run it, as we slowly press forward on the sticks, they go forward but then they stop and go backward very quickly and then goes forward again. It's like it "jolts" as its going forward. We tested the code throughly and we figured out it's not the math of the code. So we have no idea what is going on. Anyone have any suggestions?

Al Skierkiewicz
02-15-2008, 05:42 PM
Dude,
Is it possible you are trying to overcome a problem with the joysticks by writing code? I always have to ask...Are your speed controllers calibrated? This simple function will match the extremes on your joysticks to max output on the speed controller. It is very easy to watch the LEDs on the controllers to see where (or if ) they achieve full red or full green as you move the joystick forward and back. If they do not, then calibration is the easy answer. Joysticks also exhibit electrical noise as they move and this may be interpreted by your code as a human commanded direction change.

kDude
02-15-2008, 05:56 PM
Yes we calibrated the controller. We're using the xbox 360 controller with the USB chicklet so we calibrated both the analog sticks. I don't know if that changes the calibration problem or not, but there's not any LED's that indicate whether or not we're at the maximum or minimum for the joysticks.

Laaba 80
02-15-2008, 06:02 PM
We were having the same problem. When you push the joystick to turn left, the robot jerks right then goes left. The thing that confuses me is that this doesnt happen when you turn right. We did calibrate the victors, but it was a few weeks ago, it may be something to look at.
Joey