# Robot Jittering problem while driving

We have a HS 6 Motor drive with 2 motors split into the three ptcs 2-5, 6-9, and Power Expander. Whenever we intentionally burnout the motors, instead of coming slowly to a stop, the robot jitters forward and never fully comes to a stop. If we burn the motors out by hand, in initiates a regular burnout. If we burn the motors out by running into walls/game elements, it makes the drive jitter while trying to drive forward. Anyone have any problems with this, if so any solutions?

This is probably because in actual matches, each motor is actually being stressed slightly differently because of differences in friction, how the drive is chained (if at all), the center of mass, etc. If one motor on a side dies, the other two are being forced to compensate for this loss. This is likely the cause. When you “burnout” the motors by hand, you creating a controlled environment in which each wheel has equal load. That’s my best guess at least.

Our drive is set up where every motor is geared together and then chained to the wheels, so the motors should be stressed equally. Also, our robot is symmetric so the center of mass is in the center as far as left and right, but its probably further back since our batteries and motors are closer to the back of the robot, could that be a problem? Even with the drive friction that comes with chain, we still feel that a 6 motor hs should be able to run flawlessly, so this problem is very confusing for us.

What ports are everything in? And how are they geared and chained, could you send a pic? The metal sprockets pinions add a LOT of friction when touching each other, and chains aren’t known for their efficiency (although they aren’t really that bad, I think it would mostly be the sprockets).

Do you mean metal gears?

Yes. The 12-tooths are called sprockets (as my team keeps reminding me)

No. They’re called pinions.

Oh crap right. I like to call them '1’s, so I mix them up. Sorry about that, I’ll edit it.

Lol I was like

Why are the sprockets metal and more importantly, why are they touching

The gears are High Strength 36 tooth plastic gears and are geared vertically like a tower. I don’t have a picture available currently, but I’ll post one around 3:30 EST which is when I’ll have a chance to take one.

Managed to get the pictures a little bit earlier.

The burn outs we have been experiencing in normal driver control are due mainly to turning and the ptcs pretty much never trip during straight driving, even when holding a mobile goal. We have 4 omnis so could our weight being focused at the back cause problems like this?