# Description

Changes the quaternion convention in IsaacLab to match that of:
- ROS
- PhysX
- Newton
- Scipy
- Low level USD

Fixes isaac-sim/IsaacLab-Internal#744 

This PR brings massive changes throughout the code base. Almost all
users should expect their code to be impacted by these changes. We
provide a tool that should help users navigate these changes.

`./scripts/tools/find_quaternions.py` provides users with an automated
script to search throughout the code base some quaternions that do not
differ between the current code and a given commit. This can be used to
track if your code has changed the order of its hard-coded quaternions.

For instance running the following will show all the quaternions that
might need to be updated inside your extension. The dry-run flag will
make it so that the script does not attempt to modify the quaternions.
```
./scripts/tools/find_quaternions.py --path PATH_TO_YOUR_EXTENSION --all-quats --fix --context 4 --dry-run
```
If you want to modify the quaternions the script comes with an
interactive mode where it prompts you with changes to be made, to do so
remove the `--dry-run` flag:
```
./scripts/tools/find_quaternions.py --path PATH_TO_YOUR_EXTENSION --all-quats --fix --context 4
```
The `--context` flag provides more or less context before and after the
line where a quaternion was found.


Here is a sample of the interactive mode:
```shell
Searching 968 Python, 11 JSON, and 6 RST files...
Comparing against: main
Found 178 files changed from main

Found 69 potential quaternions to review:

====================================================================================================

────────────────────────────────────────────────────────────────────────────────
📍 source/isaaclab_assets/isaaclab_assets/robots/anymal.py:173 [AMBIGUOUS]
────────────────────────────────────────────────────────────────────────────────
     169 | # Configuration - Sensors.
     170 | ##
     171 | 
     172 | ANYMAL_LIDAR_CFG = VELODYNE_VLP_16_RAYCASTER_CFG.replace(
>>>  173 |     offset=RayCasterCfg.OffsetCfg(pos=(-0.310, 0.000, 0.159), rot=(0.0, 0.0, 0.0, 1.0))
     174 | )
     175 | """Configuration for the Velodyne VLP-16 sensor mounted on the ANYmal robot's base."""
────────────────────────────────────────────────────────────────────────────────
  Change: [0.0, 0.0, 0.0, 1.0] → [0.0, 0.0, 1.0, 0.0]
  Result: offset=RayCasterCfg.OffsetCfg(pos=(-0.310, 0.000, 0.159), rot=(0.0, 0.0, 1.0, 0.0))
Apply this fix? [Y/n/a/q]: Y
  ✅ Fixed!

────────────────────────────────────────────────────────────────────────────────
📍 source/isaaclab_mimic/test/test_curobo_planner_franka.py:42 [AMBIGUOUS]
────────────────────────────────────────────────────────────────────────────────
      38 | 
      39 | # Predefined EE goals for the test
      40 | # Each entry is a tuple of: (goal specification, goal ID)
      41 | predefined_ee_goals_and_ids = [
>>>   42 |     ({"pos": [0.70, -0.25, 0.25], "quat": [0.0, 0.707, 0.0, 0.707]}, "Behind wall, left"),
      43 |     ({"pos": [0.70, 0.25, 0.25], "quat": [0.0, 0.707, 0.0, 0.707]}, "Behind wall, right"),
      44 |     ({"pos": [0.65, 0.0, 0.45], "quat": [1.0, 0.0, 0.0, 0.0]}, "Behind wall, center, high"),
      45 |     ({"pos": [0.80, -0.15, 0.35], "quat": [0.0, 0.5, 0.0, 0.866]}, "Behind wall, far left"),
      46 |     ({"pos": [0.80, 0.15, 0.35], "quat": [0.0, 0.5, 0.0, 0.866]}, "Behind wall, far right"),
────────────────────────────────────────────────────────────────────────────────
  Change: [0.0, 0.707, 0.0, 0.707] → [0.707, 0.0, 0.707, 0.0]
  Result: ({"pos": [0.70, -0.25, 0.25], "quat": [0.707, 0.0, 0.707, 0.0]}, "Behind wall, left"),
Apply this fix? [Y/n/a/q]: Y
  ✅ Fixed!

────────────────────────────────────────────────────────────────────────────────
📍 source/isaaclab_mimic/test/test_curobo_planner_franka.py:43 [AMBIGUOUS]
────────────────────────────────────────────────────────────────────────────────
      39 | # Predefined EE goals for the test
      40 | # Each entry is a tuple of: (goal specification, goal ID)
      41 | predefined_ee_goals_and_ids = [
      42 |     ({"pos": [0.70, -0.25, 0.25], "quat": [0.707, 0.0, 0.707, 0.0]}, "Behind wall, left"),
>>>   43 |     ({"pos": [0.70, 0.25, 0.25], "quat": [0.0, 0.707, 0.0, 0.707]}, "Behind wall, right"),
      44 |     ({"pos": [0.65, 0.0, 0.45], "quat": [1.0, 0.0, 0.0, 0.0]}, "Behind wall, center, high"),
      45 |     ({"pos": [0.80, -0.15, 0.35], "quat": [0.0, 0.5, 0.0, 0.866]}, "Behind wall, far left"),
      46 |     ({"pos": [0.80, 0.15, 0.35], "quat": [0.0, 0.5, 0.0, 0.866]}, "Behind wall, far right"),
      47 | ]
────────────────────────────────────────────────────────────────────────────────
  Change: [0.0, 0.707, 0.0, 0.707] → [0.707, 0.0, 0.707, 0.0]
  Result: ({"pos": [0.70, 0.25, 0.25], "quat": [0.707, 0.0, 0.707, 0.0]}, "Behind wall, right"),
Apply this fix? [Y/n/a/q]: Y
  ✅ Fixed!
```


## Type of change

- Breaking change (existing functionality will not work without user
modification)
- Documentation update


## Checklist

- [x] I have read and understood the [contribution
guidelines](https://isaac-sim.github.io/IsaacLab/main/source/refs/contributing.html)
- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

---------

Signed-off-by: Kelly Guo <kellyg@nvidia.com>
Co-authored-by: Kelly Guo <kellyg@nvidia.com>

…#5754)

# Description


`scripts/imitation_learning/locomanipulation_sdg/gr00t/convert_dataset.py`
still passed `scalar_first=True` to `Rotation.from_quat` / `as_quat`,
but
since #4437 (Jan 2026) Isaac Lab returns body poses in XYZW. The script
therefore mis-interpreted recorded poses as WXYZ, corrupting every
relative-pose computation (hands, object, fixture, goal) in the GR00T
training data and causing trained policies to produce twisted-arm
rollouts.

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## Type of change

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applicable. -->

- Bug fix (non-breaking change which fixes an issue)

## Screenshots

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## Checklist

- [ ] I have read and understood the [contribution
guidelines](https://isaac-sim.github.io/IsaacLab/main/source/refs/contributing.html)
- [ ] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [ ] I have made corresponding changes to the documentation
- [ ] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [ ] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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putting an x character in it

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Co-authored-by: Kelly Guo <kellyg@nvidia.com>