SKID_STEER_NAV 🤖

A skid-steer robot simulation built with ROS2 Jazzy and Gazebo Harmonic, featuring accurate odometry and full autonomous navigation via Nav2.

📄 This repository contains the drive simulation component of our Robocon 2026 submission. For the full technical report, see the submission PDF below.

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📋 Robocon 2026 Submission

📄 View Full Submission Report (rbcn-submission.pdf)

⚠️ Scope Note: This repo covers only the drive train simulation — skid-steer odometry, Gazebo integration, and Nav2 autonomous navigation. Other subsystems (mechanical design, electronics, arena interaction) are documented in the report above.

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📸 Demo

🎥 Full navigation demo: Demos/DemoNav.mp4

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✨ Features

• Accurate skid-steer odometry via ros2_control + diff_drive_controller
• Gazebo Harmonic simulation with a full URDF/Xacro robot model
• Two operation modes: manual teleoperation and autonomous navigation
• Nav2 integration with preloaded maps and waypoint following
• Joystick support with fully configurable button mappings
• RViz2 visualization

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🛠️ Prerequisites

Dependency	Version
ROS2	Jazzy
Gazebo	Harmonic
Nav2	(ros-jazzy-nav2-bringup)
teleop_twist_joy	Optional – joystick control

Install dependencies:

sudo apt install -y \
  ros-jazzy-ros-gz \
  ros-jazzy-ros-gz-bridge \
  ros-jazzy-xacro \
  ros-jazzy-joint-state-publisher \
  ros-jazzy-teleop-twist-keyboard \
  ros-jazzy-teleop-twist-joy \
  ros-jazzy-nav2-bringup \
  ros-jazzy-navigation2 \
  ros-jazzy-slam-toolbox

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📦 Building

mkdir -p ~/ros2_ws/src
cd ~/ros2_ws/src
git clone https://github.com/adios-07/skid_steer_nav_bot.git
cd ~/ros2_ws
colcon build --packages-select skid_steer_nav
source install/setup.bash

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🚀 Launch Modes

Mode 1 — Simulation (Manual Control)

Spawns the robot in Gazebo Harmonic and opens RViz2. Control the robot manually via keyboard or joystick.

ros2 launch skid_steer_nav launch_sim.launch.py

Keyboard control (in a new terminal):

ros2 run teleop_twist_keyboard teleop_twist_keyboard

Joystick control:

Button mappings vary by controller (Xbox, PS4, Logitech, etc.) and can be configured in:

config/joystick.yaml

Launch with joystick:

Joy Node runs by default

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Mode 2 — Bringup (Autonomous Navigation)

Spawns the robot in Gazebo Harmonic with a preloaded map, opens two RViz2 windows, and brings up the full Nav2 stack.

ros2 launch skid_steer_nav bringup.launch.py

To navigate:

1. In RViz2, click 2D Pose Estimate → click and drag on the map to set the robot's starting position and orientation
2. Click Nav2 Goal → click and drag to send the robot to a target location
3. Use the Waypoint Tool to queue multiple sequential navigation goals

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🗺️ Available Maps

Map	Description
ArenaBase	Main arena environment
RoboLvl	Secondary map layout

Maps are located in the maps/ directory (*.yaml, *.pgm, *.data, *.posegraph).

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📁 Project Structure

SKID_STEER_NAV/
├── config/
│   ├── diff_drive_controller.yaml    # ros2_control controller config
│   ├── gz_bridge.yaml                # Gazebo ↔ ROS2 topic bridge
│   ├── joystick.yaml                 # Joystick button mappings
│   ├── nav2_params.yaml              # Nav2 planner/controller params
│   ├── mapper_params_online_async.yaml
│   ├── JustBot.rviz                  # RViz config (sim mode)
│   └── R2_Navigation.rviz           # RViz config (nav mode)
│
├── Demos/
│   ├── DemoNav.mp4
│   ├── img1.png
│   ├── img2.png
│   └── pdf-front.png                 # Submission PDF preview
│
├── description/                      # Robot model (URDF/Xacro)
│   ├── robot.urdf.xacro
│   ├── robot_base.xacro
│   ├── ros2_control.xacro
│   ├── gazebo_control.xacro
│   ├── inertial_macros.xacro
│   └── lidar.xacro
│
├── launch/
│   ├── launch_sim.launch.py          # Simulation + manual control
│   ├── bringup.launch.py             # Nav2 autonomous navigation
│   ├── navigation_launch.py
│   ├── localization_launch.py
│   ├── joystick.launch.py
│   └── rsp.launch.py
│
├── maps/
│   ├── ArenaBase.yaml / .pgm / .data / .posegraph
│   └── RoboLvl.yaml  / .pgm / .data / .posegraph
│
├── worlds/
│   ├── robocon.world
│   └── empty.world
│
├── rbcn-submission.pdf               # Robocon 2026 full submission report
├── CMakeLists.txt
├── package.xml
└── README.md

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⚙️ Configuration

Joystick (config/joystick.yaml)

Different controllers use different axis/button indices. Edit this file to match your specific controller layout before launching.

Nav2 (config/nav2_params.yaml)

Tune planner, controller, and costmap parameters here to adjust navigation behaviour such as obstacle inflation radius, speed limits, and planning algorithms.

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📝 Notes

• This simulation was developed as part of the DD Robocon 2026 submission, specifically to model and validate the robot's drive system behaviour in the competition arena
• The robot uses a skid-steer drive configuration managed via ros2_control
• Sensor and Gazebo topics are bridged to ROS2 using the gz_bridge config
• Odometry is published accurately and consumed directly by Nav2 for localization

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📄 License

This project is open source. Feel free to use, modify, and build upon it.