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integrations

Adapters for MuJoCo MJX dynamics in OpenSCvx BYOF.

The recommended entry-point is :func:mjx_byof, which returns a complete byof["dynamics"] dict and automatically handles free-joint quaternion kinematics for floating-base models (drones, humanoids, etc.):

from openscvx.integrations import mjx_byof

byof = {"dynamics": mjx_byof(mjx_model, qpos=qpos, qvel=qvel, ctrl=ctrl)}

For models without free joints (cartpoles, manipulators) the returned dict contains only "qvel" and dynamics={"qpos": qvel} should still be provided to :class:~openscvx.Problem. For models with free joints (nq > nv) "qpos" is included automatically — no extra imports needed.

:func:mjx_dynamics is also available for advanced users who need direct access to the BYOF callable for the qvel (acceleration) derivative.

All symbols delegate lazily so mujoco.mjx is only imported when used. The :mod:menagerie submodule is loaded lazily via attribute access.

Example — cartpole (nq == nv)::

from openscvx.integrations import mjx_byof

byof = {"dynamics": mjx_byof(mjx_model, qpos=qpos, qvel=qvel, ctrl=ctrl)}
problem = ox.Problem(dynamics={"qpos": qvel}, byof=byof, ...)

Example — quadrotor with free joint (nq=7, nv=6)::

from openscvx.integrations import mjx_byof

byof = {"dynamics": mjx_byof(mjx_model, qpos=qpos, qvel=qvel, ctrl=ctrl)}
problem = ox.Problem(dynamics={}, byof=byof, ...)

mjx_byof(*args: Any, **kwargs: Any) -> Any

Lazy delegate; imports mujoco.mjx on first call.

Source code in openscvx/integrations/__init__.py 
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def mjx_byof(*args: Any, **kwargs: Any) -> Any:
    """Lazy delegate; imports ``mujoco.mjx`` on first call."""
    from .mjx import mjx_byof as _mjx_byof

    return _mjx_byof(*args, **kwargs)

mjx_dynamics(*args: Any, **kwargs: Any) -> Any

Lazy delegate; imports mujoco.mjx on first call.

Source code in openscvx/integrations/__init__.py 
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def mjx_dynamics(*args: Any, **kwargs: Any) -> Any:
    """Lazy delegate; imports ``mujoco.mjx`` on first call."""
    from .mjx import mjx_dynamics as _mjx_dynamics

    return _mjx_dynamics(*args, **kwargs)