Retargeting Guide — Using BVH Animation on Existing Characters¶

This guide explains how to retarget BVH-imported animation to an existing Unreal Engine character.
As an example, we’ll use the default SKM_Manny mannequin and the LAFAN1 BVH dataset from Ubisoft.

Goal¶

We will import a BVH motion-capture animation, generate compatible assets,
and retarget it to SKM_Manny, whose IKRig asset (IK_Mannequin) is already configured.

IK Rig setup example

Step 1: Import BVH Animation¶

1.1 Drag & Drop BVH File¶

Drag a .bvh file (for example, dance1_subject3.bvh) into the Content Browser.

1.2 Configure Import Settings¶

In the import dialog, leave Existing Skeleton empty when importing this skeleton type for the first time,
then click Import.

Import Options Window

1.3 Result¶

The importer will automatically generate three assets in your content folder:

dance1_subject3 — Animation Sequence
dance1_subject3_Skeleton — Skeleton asset
dance1_subject3_Mesh — Preview Mesh (placeholder mesh for visualization)

Imported Files

Step 2: Create an IKRig for the Imported Skeleton¶

Create an IKRig asset based on the imported skeleton (dance1_subject3_Skeleton).
Use the target character’s IKRig (such as IK_Mannequin) as reference to define:

Bone chains
IK Goals (e.g. hands, feet, pelvis, etc.)

Example IKRig Setup for Imported Skeleton

Tip: The imported skeleton’s bone names should correspond to the BVH structure.
Match key bones (spine, arms, legs) to their UE counterparts for best retargeting results.

Step 3: Create and Configure Retargeter Asset¶

3.1 Add Retargeter Operations (Ops)¶

Within the IKRetargeter asset, configure the following operators to control motion mapping and pose transfer:

3.1.1 Pelvis Motion Op¶

Aligns the source pelvis position and rotation with the target.

Pelvis Motion Op

3.1.2 Root Motion Op¶

Controls global motion translation of the character.

Root Motion Op

3.1.3 Retarget FK Chains Op¶

Maps corresponding FK bone chains (spine, arms, legs) from the BVH skeleton to the target character.

Retarget FK Chain Op

3.1.4 Run IK Rig Op¶

Executes the IK setup on the target to finalize alignment.

Run IK Rig Op

3.2 Align Base Poses¶

Make sure both the BVH source and the target mannequin share a similar rest pose before running the retargeter.
Adjust in the Pose Alignment tab if necessary.

Pose Alignment Example

Step 4: Preview the Animation¶

After setting up the Retargeter, preview the motion in the animation viewport.

Watch the demonstration here:
🔗 AnimSequence Retargeted from BVH Motion File (YouTube)

Summary¶

After completing the steps above, your BVH-imported animation will be fully retargeted to SKM_Manny (or any compatible character).
You can now refine timing, add animation curves, or use the sequence in Sequencer or Gameplay Blueprints.