Hello, I’m trying out the RBD Car Rig and have been following some tutorials. However, when I use the RBD Bullet Solver, the wheels start to wiggle, and I can’t figure out what’s causing it. I tried replacing the wheels with simple cylinders to make sure they were 100% aligned with the rig but it didn’t fix the issue.If anyone knows what might be causing this or how to fix it I’d really appreciate the help!

Hello. After unpacking the FBX you maybe have a transform attribute that you should delete. Perhaps deleting it fixes the issue.

If not, add transform node after attribute delete and rotate Y by 90 degrees until the truck points in +X axis.
Also align your trajectory curve. Adjust the curve so that the first segment points along +X axis before twisting into rest of your curve.
Basically after selecting curve node, look at the geometry spreadsheet and make sure Y and Z values are identical on point 0 and point 1 (which should correspond to the first segment of the curve) while X on Point 1 should have a bigger value than on Point 0.

You should adjust your curve so point 0 is placed slightly behind center of the car, point 1 is in front of the car and offset only on X while keeping the same Y and Z values. Point 2 should also be further out along the X and point 3 you can start twisting on any axis according to your liking.