Simulation

The genbu_simulator package provides a Gazebo simulation environment for the Genbu robot.

Prerequisites

• ROS 2 (Jazzy or later)
• ros_gz_sim, ros_gz_bridge packages
• genbu_description package

Launching the Simulation

Use sim_bringup.launch.xml to start the full simulation stack:

ros2 launch genbu_simulator sim_bringup.launch.xml

This launch file:

1. Starts the Gazebo simulator with the selected world.
2. Launches the robot state publisher (with use_sim_time:=true).
3. Spawns the Genbu robot into the simulation.
4. Bridges the lidar sensor data from Gazebo to the ROS 2 /scan topic.

Launch Arguments

Argument	Default	Description
world	default	Name of the world file to load (see Available Worlds).
robot_name	genbu	Name assigned to the spawned robot entity in Gazebo.

Selecting a World

Pass the world argument to choose a different simulation environment:

ros2 launch genbu_simulator sim_bringup.launch.xml world:=obstacle_course

Available Worlds

World	Description
default	Empty flat plane with directional lighting. Good for basic bring-up testing.
obstacle_course	Flat plane populated with box pillars and cylinders placed around the robot's starting position to exercise obstacle detection and navigation.

ROS 2 Topics

Once the simulation is running, the following topics are available:

Topic	Type	Description
/scan	sensor_msgs/msg/LaserScan	Lidar scan data bridged from the Gazebo GPU lidar sensor.
/robot_description	std_msgs/msg/String	URDF published by the robot state publisher.
/tf	tf2_msgs/msg/TFMessage	Transform tree published by the robot state publisher.

Notes

WSL / Non-NVIDIA Environments

The sim_bringup.launch.xml file automatically sets the following environment variables to enable Mesa software rendering when a hardware GPU is not available (e.g. WSL or CI environments):

Variable	Value
LIBGL_ALWAYS_SOFTWARE	1
GALLIUM_DRIVER	llvmpipe

No extra configuration is required; the launch file handles this automatically.