unknown_robot2

unknown_robot2 is a ROS 2 mobile robot project for simulation, SLAM, localization, and autonomous navigation using Nav2.

This project contains the robot description, Gazebo simulation files, navigation configuration, maps, launch files, and RViz setup for a custom differential-drive mobile robot.

What Can You Do With It?

• Simulate a custom mobile robot in Gazebo
• Visualize robot model, TF, laser scan, odometry, and map in RViz2
• Build a map using SLAM Toolbox
• Navigate autonomously using Nav2
• Test global planner and local planner behavior
• Tune costmaps, inflation layer, controller, and planner parameters

Features

• ROS 2 Jazzy / Ubuntu 24.04 support
• Gazebo simulation
• Differential-drive robot model
• LiDAR sensor support
• Camera sensor support
• IMU support
• SLAM Toolbox mapping
• Nav2 autonomous navigation
• AMCL localization
• RViz2 visualization

Workspace Structure

unknown_robot2_ws/
├── LICENSE
├── README.md
└── src
    ├── unknown_robot2_bringup
    │   ├── LICENSE
    │   ├── package.xml
    │   ├── resource
    │   │   └── unknown_robot2_bringup
    │   ├── setup.cfg
    │   ├── setup.py
    │   ├── test
    │   │   ├── test_copyright.py
    │   │   ├── test_flake8.py
    │   │   └── test_pep257.py
    │   └── unknown_robot2_bringup
    │       └── __init__.py
    ├── unknown_robot2_description
    │   ├── CMakeLists.txt
    │   ├── include
    │   │   └── unknown_robot2_description
    │   ├── launch
    │   │   └── display.launch.py
    │   ├── LICENSE
    │   ├── media
    │   │   └── materials
    │   ├── meshes
    │   ├── package.xml
    │   ├── rviz
    │   │   ├── nav2_test.rviz
    │   │   ├── odom_test.rviz
    │   │   ├── slam_toolbox_test.rviz
    │   │   └── unknown_robot2.rviz
    │   ├── src
    │   └── urdf
    │       └── unknown_robot2.urdf.xacro
    ├── unknown_robot2_gazebo
    │   ├── config
    │   │   └── empty_world.config
    │   ├── launch
    │   │   ├── empty_gazebo.launch.py
    │   │   ├── gazebo.launch.py
    │   │   └── gz_slam_world.launch.py
    │   ├── LICENSE
    │   ├── package.xml
    │   ├── resource
    │   │   └── unknown_robot2_gazebo
    │   ├── setup.cfg
    │   ├── setup.py
    │   ├── test
    │   │   ├── test_copyright.py
    │   │   ├── test_flake8.py
    │   │   └── test_pep257.py
    │   ├── unknown_robot2_gazebo
    │   │   ├── __init__.py
    │   │   └── odom_to_tf.py
    │   └── worlds
    │       ├── auto_test_world.sdf
    │       └── empty.sdf
    └── unknown_robot2_navigation
        ├── behavior_trees
        │   └── nav_to_pose_clear_costmap.xml
        ├── config
        │   ├── nav2_map_params.yaml
        │   └── nav2_slam_params.yaml
        ├── launch
        │   ├── nav2_map.launch.py
        │   └── nav2_slam.launch.py
        ├── LICENSE
        ├── maps
        │   ├── auto_test_map.pgm
        │   └── auto_test_map.yaml
        ├── package.xml
        ├── resource
        │   └── unknown_robot2_navigation
        ├── setup.cfg
        ├── setup.py
        ├── test
        │   ├── test_copyright.py
        │   ├── test_flake8.py
        │   └── test_pep257.py
        └── unknown_robot2_navigation
            └── __init__.py

Requirements

• Ubuntu 24.04
• ROS 2 Jazzy
• Gazebo Harmonic
• Nav2
• SLAM Toolbox
• RViz2
• ros_gz bridge packages

Install common dependencies:

sudo apt update

sudo apt install -y \
  ros-jazzy-ros-gz-bridge \
  ros-jazzy-ros-gz-sim \
  ros-jazzy-slam-toolbox \
  ros-jazzy-navigation2 \
  ros-jazzy-nav2-bringup \
  ros-jazzy-tf2-ros \
  ros-jazzy-tf2-tools \
  ros-jazzy-rviz2 \
  ros-jazzy-nav-msgs \
  ros-jazzy-geometry-msgs \
  ros-jazzy-sensor-msgs \
  ros-jazzy-tf2-msgs \
  python3-colcon-common-extensions \
  python3-rosdep \
  python3-venv \
  python3-pip

Installation

Clone the repository:

cd ~
git clone git@github.com:wattanatum/unknown_robot2.git unknown_robot2_ws
cd unknown_robot2_ws

Install dependencies:

rosdep update
rosdep install --from-paths src -y --ignore-src

Build the workspace:

colcon build --symlink-install

Source the workspace:

source install/setup.bash

Optional: add to .bashrc:

echo "source ~/unknown_robot2_ws/install/setup.bash" >> ~/.bashrc
source ~/.bashrc

Quickstart

Check robot TF

ros2 launch unknown_robot2_description display.launch.py

SLAM Toolbox Mapping

Terminal 1: Launch Gazebo Simulation

ros2 launch unknown_robot2_gazebo gazebo.launch.py 

Terminal 2: Launch SLAM Mapping

ros2 launch slam_toolbox online_async_launch.py use_sim_time:=true

Terminal 3: Launch nav2 for move and avoid obstacle whlie mapping

ros2 launch unknown_robot2_navigation nav2_slam.launch.py

Terminal 4: Run RViz2

rviz2

Open RViz2 config in this path:

~/unknown_robot2_ws/src/unknown_robot2_description/rviz2/slam_toolbox_test.rviz

5. Save Map

ros2 run nav2_map_server map_saver_cli \
  -f ~/unknown_robot2_ws/src/unknown_robot2_navigation/maps/auto_test_map

Navigation with Saved Map

Terminal 1: Launch Gazebo Simulation

ros2 launch unknown_robot2_gazebo gazebo.launch.py 

Terminal 2: Launch nav2 with saved map

ros2 launch unknown_robot2_navigation nav2_map.launch.py

Terminal 3: Run RViz2

rviz2

Open RViz2 config in this path:

~/unknown_robot2_ws/src/unknown_robot2_description/rviz2/nav2_test.rviz

Important ROS 2 Topics

Topic	Description
/cmd_vel	Robot velocity command
/odom	Odometry data
/scan	LiDAR scan
/imu	IMU data
/tf	Dynamic transforms
/tf_static	Static transforms
/map	Occupancy grid map
/goal_pose	Navigation goal pose

Navigation Stack

This project uses Nav2 for autonomous navigation.

Main Nav2 components:

• Planner Server
• Controller Server
• Behavior Tree Navigator
• AMCL
• Map Server
• Global Costmap
• Local Costmap
• Recovery Behaviors
• Velocity Smoother

Costmap Tuning

Inflation layer example:

inflation_layer:
  plugin: nav2_costmap_2d::InflationLayer
  inflation_radius: 0.25
  cost_scaling_factor: 3.0

Lower inflation_radius reduces the obstacle safety area.

Higher cost_scaling_factor makes obstacle cost drop faster.

Build Again After Editing Code

cd ~/unknown_robot2_ws
colcon build --symlink-install
source install/setup.bash

Troubleshooting

Robot does not move

Check:

ros2 topic echo /cmd_vel
ros2 topic echo /odom
ros2 run tf2_tools view_frames

No map in RViz2

Check:

ros2 topic list | grep map
ros2 topic echo /map --once

No LiDAR scan

Check:

ros2 topic echo /scan

TF problem

Check:

ros2 run tf2_ros tf2_echo odom base_link

Author

Kasiphat Uppaphak
GitHub: wattanatum