Motrix Robot Models

motrix-robots provides reusable robot configurations, default poses, and model assets for simulation.

Simulation configuration

from motrix_robots import Microduck, UnitreeGo2Robot
from motrix_env_core.config.scene.base import RobotCfg

microduck = Microduck()
robot = UnitreeGo2Robot(prefix="robot_")
robot.validate("robot")
assert isinstance(robot, RobotCfg)
assert robot.resolved_base_link_name == "robot_base"

Use key_pose for named joint poses and init_key_pose to select the initial pose. Resolve prefixed model names with robot.resolve_name(name). Tasks supply the scene and choose their sensors.

Selecting built-in models by ID

Installed robot packages are discovered automatically. Select a built-in model by its registered ID:

from motrix_env_core.registry import make_robot_config

robot = make_robot_config("go2")

The IDs are anymal_c, g1-29dof, go1, go2, k1, dex-evt, and microduck.

Programmatic actuator overrides

BodyCfg (and therefore RobotCfg) owns format-neutral actuators for both MJCF and URDF models. None preserves imported actuators; a dictionary replaces the entire model instance's actuator set; {} removes all of them. Keys supply actuator names, so ActuatorCfg does not duplicate a name field. Override joint names are model-local, before prefix/suffix decoration. Other instances and source asset files are not modified.

from motrix_env_core.config.scene.actuator import MotorActuatorCfg

robot = UnitreeGo2Robot(
    actuators={
        "FL_hip_motor": MotorActuatorCfg(joint_name="FL_hip_joint", force_range=(-20.0, 20.0)),
        # Declare the other controlled joints here: this replaces, not appends.
    },
)

MotorActuatorCfg declares unit-transmission direct effort. PositionActuatorCfg declares a native position servo using kp, absolute damping kv, and optional control/force ranges. Actuator order follows dictionary insertion order. Replacement resets keyframe actuator controls/activations while retaining joint poses and velocities. Dex-EVT declares its drives on the robot instance.

Model modules and assets

Import these model classes and helpers directly from motrix_robots:

Defining module	Public configuration classes
motrix_robots.unitree	UnitreeG129Dof, UnitreeGo1Robot, UnitreeGo2Robot
motrix_robots.anymal	AnymalC
motrix_robots.booster	BoosterK1
motrix_robots.dex_evt	DexEvt
motrix_robots.microduck	Microduck
motrix_robots.quadruped	QuadrupedLegCfg, QuadrupedLegsCfg, QuadrupedRobotCfg
motrix_robots.humanoid	HumanoidRobotCfg

Bundled model descriptions, meshes, and model textures are under src/motrix_robots/assets/. Task scenes, ground textures, and terrain assets belong to motrix_envs. Asset licenses and attribution remain with their asset directories; see the root THIRD_PARTY_NOTICES.md for the release inventory.