PDA

View Full Version : Servo Centering Issue


WhiteSatin
2009.07.15, 05:47 AM
Brand new MR-02. If I turn to the right then return to center, the wheels will go past center and stop slightly off to the left, a few degrees. When I turn to the left and then return to center, the wheels stop slightly off to the right. If I push the wheels by hand, they will jump from one side to the other, not frrom steering slop, but actual movement from the servo itself. I've tried 2 different radios, same thing happens with each. I've tried both of these radios on 2 other cars that work fine. So I know it's the car.

I know the typical response is potentiometer, but obviously it's working to some degree. Do they every partially fail where they can't quite find center but almost do?

TannerT
2009.07.15, 09:23 AM
Brand new MR-02. If I turn to the right then return to center, the wheels will go past center and stop slightly off to the left, a few degrees. When I turn to the left and then return to center, the wheels stop slightly off to the right.

Does it go lock to lock after re-centering? What does it do when you turn everything on and let it sit? Does it center? You could try adjusting the silver pot on top of the board. Is your steering trim centered?

Eman
2009.07.15, 03:25 PM
Sounds like you need to clean or replace the pot. Weird being its new.....

WhiteSatin
2009.07.15, 07:36 PM
Do you mean does it go to lock on its own, or can I turn it to lock? Well I can turn it to lock just fine. Except for not centering in quite the right place, and centering in 2 places, the steering acts normal.

If I turn it on and let it sit, it picks either slightly left of center or slightly right of center and just stays there, no jumping or anything. It never picks dead center though, it always goes either left or right of center.

I could make it pick dead center 50% of the time if I adjusted the trim, but then it would be way off center when it switched over to its other version of center, so it wouldn't help any to trim it.

color01
2009.07.15, 08:34 PM
That probably indicates that the pot is shifting, and then staying in its shifted position -- thus you have a range of steering angles that the car may "think" is center.

Try operating your servo with the MR02's top cover removed. You'll be able to see better what the issue is. ;)