RigidBody3D collision penetration issue

[waxen bane]

I'm having an issue with RigidBody3Ds penetrating through CollisionShape3Ds.

I have a truck (VehicleBody3D node) with a AnimatableBody3D child node which houses the collisions for the bed of the truck. I have various objects (boxes, capsules and cylinders) that are RigidBody3Ds. With any one of the objects in the truck bed when moving they'll eventually hit the back of the truck and penetrate through the collision. Fortunately, they don't fall out. Please see the attached video that showcases my issue. I am using the Jolt physics engine and Godot 4.4.1 (Stable).

I've tried various things:

• Increasing physics ticks per second (if this is at 1000 it is nearly 100% perfect. In some cases I've noticed it'll still penetrate).
• Enabling continuous collision detection
• Adjusting penetration slop, speculative contact distance, baumgarte stabilization factor, CCD movement threshold and max penetration, recovery iterations & amount, collision margin fraction, and solver iterations.
• Increasing collision thickness and having multiple collision shapes in the same spot.
• Messing around with physic material configurations.

I'm probably forgetting some stuff but that should be the majority of it.
I want the objects to be able to interact with each other (when there is multiple) and their outside environment (such as a long capsule hanging over the side and hitting a tree for example) so locking them to a specific spot won't be an option.
Any ideas will be appreciated :)

[spare dirge]

First thing that bothers me with this approach is the AnimatableBody. I think you should make the bed of the truck part of the Vehiclebody3d using multiple box Collision shapes.

This way you'll get Rigidbody vs Rigidbody ( Vehiclebody extends Rigidbody) collisions which should be more reliable.

Also, if you haven't done so already, disable can_sleep for your Rigidbodies - at least while testing

[waxen bane]

Thanks for the reply! I posted my issue to reddit and someone said the same thing. Removing the AnimatableBody3D seemed to have fixed the issue. Although my vehicles handling is now pretty wacky but I should be able to fix that. I believe I have can_sleep set to true already. Thanks again!

[spare dirge]

The vehiclebody probably calculates its center of mass and inertia automatically from the positions and sizes of the collision shapes like a pure Rigidbody would.
You could set it's center of mass manually, if that option is available