Detailed Description

Tutorial 4: Transmissions

This tutorial demonstrates using ros2_control transmissions with MuJoCo.
Transmissions allow mapping between actuators and joints with mechanical
reduction ratios and offsets.

Key concepts:
- SimpleTransmission interface from transmission_interface
- Mechanical reduction configuration (gear ratios)
- Actuator-to-joint mapping in MJCF
- Runtime MJCF modification to rename joints to actuators

Resources used:
- demo_resources/scenes/scene.xml (base scene)
- demo_resources/robot/test_robot.xml (modified at runtime for actuator names)
- test_robot.urdf with use_transmissions:=true

Usage:
    ros2 launch mujoco_ros2_control_demos 04_transmissions.launch.py
    ros2 launch mujoco_ros2_control_demos 04_transmissions.launch.py headless:=true