Server Launch Options

The ROS 1 server is launched with mujoco_ros/launch/launch_server.launch:

roslaunch mujoco_ros launch_server.launch use_sim_time:=true

Required Argument

use_sim_time: Required. Sets /use_sim_time. Use true for fully simulated systems. Use false only when another clock source owns ROS time.

Runtime Arguments

ns: Optional namespace passed to the server.
unpause: Starts physics immediately when true. Defaults to false.
headless: Disables the interactive GUI when true. Offscreen rendering can still be enabled. Defaults to false.
render_offscreen: Allocates offscreen camera rendering resources when true. Camera streams are still lazy and render only while subscribed. Defaults to true.
no_render: Shorthand for headless:=true and render_offscreen:=false. Use this for compute-only server runs. Defaults to false.
no_x: Deprecated compatibility option. It is treated as a no-render request when set and should be replaced by no_render.
modelfile: MuJoCo XML or MJB file to load. Defaults to $(find mujoco_ros)/assets/pendulum_world.xml.
wait_for_xml: Waits for model XML on the parameter server instead of immediately loading a file path. Defaults to false.
realtime: Desired real-time factor. Values in (0, 1] cap the simulation speed; -1 runs as fast as possible. If unset, the model’s MuJoCo realtime value is used.
num_sim_steps: Automatically exits after this many MuJoCo simulation steps. -1 disables the limit.
mujoco_threads: Deprecated. Number of MuJoCo worker threads requested by the server. The launch file defaults to 1; the server falls back to its internal default when the parameter is not set. Values greater than 1 can increase CPU usage because MuJoCo worker threads busy-wait; see google-deepmind/mujoco#2746. MuJoCo upstream is changing the public threading API to internal-only usage, so this behavior will change in the future and mujoco_ros will need its own threading API.
mujoco_plugin_config: YAML file loaded before the node starts. Use it to define MujocoPlugins and plugin-specific configuration.
initial_joint_states: YAML file loaded into the server namespace. Defaults to $(find mujoco_ros)/config/initial_joint_states.yaml.

Access Control and Logging

eval_mode: Enables evaluation restrictions. Mutating service calls require a matching admin_hash, and the sensors plugin suppresses ground-truth topics. Defaults to false.
admin_hash: Hash required by protected service calls while eval_mode is enabled.
verbose: Loads the configured ROS console file and enables more detailed logs. Defaults to false.
console_config_file: ROS console configuration used when verbose is true. Defaults to $(find mujoco_ros)/config/rosconsole.config.

Developer Arguments

debug: Runs the server under gdb --args.
debug_server: Runs the server under gdbserver localhost:1234. This overrides normal debug mode.
valgrind: Runs the server under valgrind. Do not combine this with debug.
valgrind_args: Extra arguments passed to valgrind.
profile: Sets CPUPROFILE=/tmp/profile.out for profiler-enabled builds.

ROS 2 Launch Differences

The hybrid-devel branch provides a ROS 2 launch file at mujoco_ros/launch/ros2/launch/launch_server.launch.xml. It mirrors the ROS 1 arguments but uses ROS 2 launch syntax, $(find-pkg-share ...) paths, exec= instead of type=, ROS 2 log-level arguments, and <param from=...> for YAML loading. It also adds gdb_term_cmd for opening gdb in a terminal.