Fix frame orientation offsets for skeleton model BVH retargeting #129
+893
−2
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
The skeleton model (based on OpenSim Hamner2010) has a 90-degree X-axis rotation baked into the pelvis quaternion, which differs from standard robotics conventions used by other supported robots (G1, T1, etc.). Changes: - Update quaternion offsets for all body parts to compensate for the skeleton's rotated coordinate frame - Pelvis/Torso: [0.5,0.5,0.5,0.5] -> [0.707,0,0.707,0] (90° Y-rotation) - Legs: [-0.5,0.5,0.5,-0.5] -> [0.707,0.707,0,0] (90° X for Z-axis joints) - Feet: [-0.707,0.707,0,0] -> [0,1,0,0] (180° X for foot orientation) - Arms: [0.5,0.5,-0.5,-0.5] -> [0,0.707,0,0.707] (aligned with rotated torso) - Enable use_ik_match_table1 for two-stage IK convergence - Fix body name consistency (radius_l -> hand_l) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Summary
The skeleton model (based on OpenSim Hamner2010) has a 90-degree X-axis rotation baked into the pelvis quaternion (
quat="0.7071, 0.7071, 0, 0"), which differs from the standard robotics conventions used by other supported robots (G1, T1, etc.).This PR updates the quaternion offsets in
bvh_lafan1_to_skeleton.jsonto compensate for the skeleton's rotated coordinate frame:[0.5, 0.5, 0.5, 0.5]→[0.707, 0, 0.707, 0](90° Y-rotation to compensate for 90° X pre-rotation)[-0.5, 0.5, 0.5, -0.5]→[0.707, 0.707, 0, 0](90° X-rotation for Z-axis joint flexion)[-0.707, 0.707, 0, 0]→[0, 1, 0, 0](180° X-rotation for foot orientation)[0.5, 0.5, -0.5, -0.5]→[0, 0.707, 0, 0.707](aligned with rotated torso frame)use_ik_match_table1for two-stage IK convergenceradius_l→hand_l)Test plan
🤖 Generated with Claude Code