Running Simulations

All simulations are launched through the sim CLI. It builds the ROS 2 workspace, sets up the environment, and runs the launch file for the specified robot.

Native (pixi)

Terminal

pixi run sim native <robot_name>

For example, to run the arm simulation:

Terminal

pixi run sim native arm

Dev Container

Inside devcontainer

sim docker <robot_name>

Options

Both sim native and sim docker accept the same flags:

Option	Description
--no-build	Skip the colcon build step. Use this when you haven’t changed any code and want a faster startup.
--build-only	Build the workspace but don’t launch the simulation. Useful for checking if your changes compile.

Terminal

# Skip building (already built)
pixi run sim native arm --no-build

# Only build, don't launch
pixi run sim native arm --build-only

Cleaning the workspace

To remove build artifacts and do a clean rebuild:

Terminal

pixi run sim clean

This deletes build/, install/, and log/ directories. Use this when you encounter unexplained build failures.

Troubleshooting

Build fails with cryptic errors: Run sim clean to delete stale build artifacts, then try again. Stale artifacts are the most common cause of unexplained build failures.

Gazebo window doesn’t appear (Dev Container): Connect via your VNC viewer at localhost:5900 and verify it works with xeyes. If the display isn’t running, restart it with .devcontainer/x_server.sh.

Package not found errors after launch: Try running sim clean and building again.