mujoco-robot 0.0.1

A general Python interface class for robot simulations using MuJoCo.

MuJoCo Robot

🚧 Work in progress.

A general Python interface for robot simulations using MuJoCo. Its public API mirrors pybullet_robot so that controllers written against that backend can be run here with minimal changes.

MujocoRobot gives you a single object to load, introspect, control, and read state from a robot, implemented directly on MjModel + MjData.

Installation

Requires Python >= 3.10 and mujoco >= 3.2.

From source

git clone https://github.com/justagist/mujoco_robot
cd mujoco_robot
pip install -e .

Development

pip install -e ".[dev]"   # test + lint + build tooling
ruff check .
pytest -q

Design notes

• Quaternions: the external API uses [x, y, z, w] (scipy convention); values are converted to MuJoCo's [w, x, y, z] only at the boundary.
• Angles: joint positions, velocities, and limits are in radians. A compiled model always stores radians regardless of the MJCF compiler angle setting, so no conversion is done.
• Backend: pure MjModel + MjData (no client-server). Pass an existing (model, data) to wrap a robot that is already part of a scene.
• End-effector frame: a body by default; a site can be used optionally.
• Control: writes data.ctrl when the model has actuators, otherwise falls back to data.qfrc_applied with a Python PD loop.
• Fixed vs floating base: a structural free joint (added via MjSpec), not a load-time flag.

Status

Work in progress, built up in phases. Panda (from robot_descriptions) is the reference test robot.

License

MIT (c) Saif Sidhik