Physics asset / Blender scale issue

I have an issue with my physics asset where the automatically created capsules are way too large. In blender, everything looks fine, just like the skeleton and skeletal mesh in the engine. The mesh and the armature both have a scale of 1, and the export scale is also set to 1. However, when I open my skeletal mesh, the bone containing every single bone of the armature has now a scale of 100 (for both bone and reference). Whenever I want to change that, the number jumps from 1 to either -970440 or around 980000 immediately. Manually created capsules for bones of all sizes have the same dimensions every single time and I can’t change the radius. When I set my blender scales to 100 though, while changing the export scale to 0.01, now the capsules are fine, but the character is now 100 times larger than it should be. Another strange observation is that in blender,having a scale of 1 on the mesh and armature makes them both equally as tall, but sometimes, having a scale of 100 on the mesh and a scale of 10 on the armature has the same result, and they are again equally as tall. I honestly don’t know whether it’s an unreal engine or blender issue, it could also be the export settings…

First screenshot shows the scale and the skeletal mesh, second one the physics asset. Thanks for any help.

Hello there @culum88 !

Another clash between UE and Blender for the list, and quite an unusual one. If all parameters of the capsules are settled in Blender, the resulting difference in Unreal should not be that high.

In general, the workflow between these two boils down to ensure that any and all transforms from your meshes are applied, and that all scaling values are normalized. After that, check the following settings for your export:

  • Apply Scalings set to “FBX Units Scale”
  • Forward set to “-Y Forward”
  • Up set to “Z Up”
  • Apply Unit, Use Space Transform, and Apply Transform, all set to “Enabled”

As for Armature:

  • Set the Armature node to “Root”
  • Uncheck “Add Leaf Bones”
  • Check “Only Deform Bones”

After all changes are applied, export your file again as a .fbx, and import it into UE with default settings on engine side.

If the issue persists, it’s worth testing to incorporate Blender addons into the workflow, like Send2UE: