Heavy Vibrations coming from all PAL wheels

[fat-lobyte]

Hi! I am experiencing serious jitter and vibrations, whenever either the PAL wheel or the PAL adjustable wheels are intalled.

I am pretty sure it's the wheels, because this craft does not vibrate:

but this one does:

[BobPalmer]

I'll take a look!

[dboi88]

I had done my tests with the inline wheel which were bad at times but the none adjustable ones shake the world! The adjustable wheel get worse the further away from position 0 you get if that helps.

[BobPalmer]

Sorted in next release

[fat-lobyte]

Just a little heads up, this is not fully fixed, it might actually be worse in some situations now.
I'm gonna do some investigating, then I'll come back with more details.

Do you prefer to have a new Issue opend?

[BobPalmer]

We can use this old issue, but I do need more examples as I was rolling all over the place with the wheels with no issues the other day.

[fat-lobyte]

Alright, the issue seems to depend on the servo angles and the loading. The further down you go, and the more weight is on the wheels, the more likely they are to jitter.

Please download the following craft: PAL-Jitter.zip

If you remove the two tanks completely, the craft stays rock solid. If you leave them on, and set the servos to -60° for the outer/inner hinge, it starts rocking like crazy.
If the tanks are loaded partially, the jitter starts later.

One could even define a jitter point: If the Outer/Inner hinge of the Lateral PAL Wheel is set to an angle below this point, the craft starts to jitter.

Full tanks: -36°
Half tanks: -43°
1/3 of tanks: -55°
Empty tanks: No visual jitter, but craft slides around
No tanks: No visual jitter, craft stays in place.

A similar effect can be produced when using "Hack Gravity": the higher the gravity, the more it jitters.

The workarounds for now are:

• Keep the wheels straight, at 0° for inner/outer hinge. No Jitter at all
• Keep the mass of the crane small (obviously a problem when picking stuff up). Increasing the number of wheels does not seem to help though.

[maranble14]

For me the issue extends beyond just vibration... These wheels are deliberately trying to flip my craft. I have two example videos I've uploaded. Both instances are without any sort of SAS or user input. Thanks :)

https://youtu.be/fJZiJ4DuR5Y

https://youtu.be/_pVGQSlL3D0

[wisnoskij]

This might be a stock issue? I had the same sort of vibration (sometimes positive feedback vibration) with wheels with stock parts long before this mod was ever installed.

[Joker58th]

I'm experiencing the same issue as described by fat-lobyte with a similar build. The heavier it is and the lower it goes, the thing starts dancing all over the place even to the point of flipping. I am only testing on Kerbin runway at this point. Is anyone actively looking at this? I love this mod for base building and this crane style rover similar to above but with docking port on its belly is the only way I've found that works half way decent.