Free constraints (e.g. PhysicsHandle) don't work with SkeletalMesh

Development World Creation
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We use a slightly modified version of UPhysicsHandleComponent to attach weapons to characters. Like the stock version, it creates a Physx joint with ‘free’ motion along all six axes, and linear/angular motors that try to maintain the constraint.

This approach works great with static meshes. However when trying with a SkeletalMesh with a physics asset, the constraint motors cannot maintain connection, even with no force limit. There is ‘something’ happening, but it’s as if the free constraints aren’t prioritized the same way as locked constraints linking bodies in the grabbed SkeletalMesh.

This behavior repros with physics constraint components. Set them to have unlimited motion with strong motors, and static meshes stay in place, skeletal meshes do not

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Hi Adrian,

I’d expect this to work with skeletal meshes. In 4.13 we’ve introduced a physical animation component which works exclusively with skeletal mesh components. You can check out the code, but the way it works is similar to what you describe. We create dummy actors with constraints that have free linear/angular motion. We then apply motors.

I just tried this with a ragdoll and it seems to work. Have you tried changing the interpolation speed down to 1? I did change the linear stiffness and damping to be 10x the default values, but this isn’t unexpected given that my ragdoll consists of many bodies.

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you’re right - this was user error; thank you for the response