Update: Ossim now supports Blender 4. Please update your addon to version 1.5.0!
Ossim is a simulation baking tool. It allows you to generate an armature and skinned geometry based on physics simulation to use in game engines and realtime applications such as Unreal Engine, Godot, Unity and many others.

Showcase

Generated armature in Blender

Exported skeletal mesh in UE4

Changelog

Version 1.5.0

• Added support for Blender 4.0+
• Code refactoring and cleanup
• Fixed small issues with the armature generation procedure.
• Added faster rigidbody generation procedure (simplier version of rigidbody armature generation).
  

Version 1.4.2

• Blender 3.0 support
• Fixed cloth generation

Version 1.4.1

• Blender 2.91 support

Version 1.4.0

• Blender 2.8 API changes implemented (including outliner fixes)
• Added transformation cleaning options
• Bugfixes
  • Fixed a bug with armature as parent always having OBJECT type.

Version 1.3.0

• Blender 2.8 support
• Bugfixes

Version 1.2.0

• Cloth simulations bake
• UI improvements
• Bug fixes

Version 1.1.0

• Code refactor
• Autokeyframing feature
• UI/UX improvements (more options and context-aware tools)
• Bug fixes for armature generation:
  • Duplicated geometry now use the same modifiers/mesh data/materials as the originals
  • Generator now properly treats modifiers and non-mesh object in the selection
  • Animated physics assets now treated correctly

Installation

• Put python file inside Blender scripts folder (Blender\2.**\scripts\addons)
  • OR simply press Install Addon From File button in Addons tab (Preferences)
• Enable addon by clicking on checkbox

How to use

• Bring any mesh to blender and break it however you want
  • You can use built-in Blender addon called Cell Fracture
  • You can also use PhysAssist addon
• Set rigid body physics for all geometry pieces you want to simulate. You can make simulation conditions as complex as you like (adding wind, vortex or another rigidbody colliding with your mesh)
• Select just geometry you want to bake. Move it to separate layer for convenience.
• Specify target layer for skinned geometry.
• Run armature generation (Tool located under Tools->Misc->Ossim)
• Select your generated armature and run autokeyframe feature
• Select armature and skinned mesh and export it.

Discussion

• You can reach me on twitter: @GubinPetr
• Polycount forum thread: https://polycount.com/discussion/202266/ossim-rigid-body-simulation-baking-for-blender
• BlenderArtists forum thread: https://blenderartists.org/t/addon-ossim-bake-rigidbody-simulation-to-armature-ue4-unity/1115900