OHMS-NetSim: Outdoor Heterogeneous Multi-Robot System Network Simulator

OHMS-NetSim is a high-fidelity simulation framework for developing and testing algorithms for Outdoor Heterogeneous Multi-Robot Systems. Built on ROS 2 Humble and Gazebo, it provides a realistic platform for researchers to validate navigation, communication, and coordination strategies in challenging outdoor environments.

The key feature of OHMS-NetSim is its custom Gazebo plugin that simulates realistic, obstacle-dependent communication degradation based on established scientific models, enabling the study of communication-aware robotics.

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Table of Contents

• Key Features
• Installation
• Getting Started and Tutorials
• Project Structure
• Community and Contribution
• Citation
• Acknowledgements

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Key Features

• Heterogeneous Teams: Simulate complex teams of Unmanned Ground Vehicles (UGVs) and Unmanned Aerial Vehicles (UAVs).
• Realistic Outdoor Worlds: Includes several pre-built environments, such as a marsyard and dense forests.
• Modular Scenario Definition: Easily define and launch complex multi-robot scenarios using a combination of YAML configuration files and ROS 2 launch files.
• Scientifically-Grounded Comms Emulation: A custom Gazebo plugin simulates path loss and packet drop rates based on peer-reviewed models, allowing for realistic testing of communication-aware algorithms.
• ROS 2 Humble Integration: Fully integrated with the ROS 2 ecosystem, providing a standard platform for robotics research and development.

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Getting Started and Tutorials

• Getting Started: Tutorial to start a basic simulation.
• Tutorials:
  • Update Environment: TODO: Add step-by-step guide for simulating new Gazebo worlds.
  • Update Robot Models: TODO: Add step-by-step guide for customizing existing robot models or integrating new robots into the simulation.

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Project Structure

The repository is organised to allow for easy customisation and extension.

• /launch: Contains the top-level ROS 2 launch files for starting different simulation scenarios.
• /config: Holds the YAML files used to configure the parameters for each simulation, such as robot names, initial poses, and sensor loadouts.
• /worlds: Contains the Gazebo .sdf world files.
• /models: Contains the Gazebo .sdf model files for the robots and other objects in the world.
• /src: Contains the C++ source code for the CommsEmulatorHelper Gazebo plugin.
• /docs: Contains detailed project documentation.

To create a new scenario, you can create a new YAML file in the /config directory and a corresponding launch file in the /launch directory.

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Community and Contribution

We welcome contributions from the community! Whether you are reporting a bug, suggesting a new feature, or submitting code, your input is valuable. Please consult our community guidelines to get started.

• Project Roadmap: Outlines our phased release plan, from the current prototype to future stable versions.
• Contribution Guidelines: Explains how to contribute to the project.
• Code of Conduct: Our commitment to a welcoming and inclusive community.

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Citation

If you use OHMS-NetSim in your research, please cite our work.

@inproceedings{boralessa-2025-ohmsnetsim,
  title     = {OHMS‑NetSim: Enabling Obstacle‑Aware Network‑Physics Co-Simulation for Outdoor Multi‑Robot Applications},
  author    = {Kalhan Boralessa, David Adama, Ahmad Lotfi, and João Filipe Ferreira},
  booktitle = {UKCI},
  year      = {2025},
  address   = {Edinburg, UK}
}

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Acknowledgements

The simulation worlds marsyard2020, marsyard2020forest, and marsyard2020forest5x are adapted from the leo_simulator-ros2 package, developed by the Mars Society Polska and the Leo Rover team. We extend our gratitude for their excellent work.

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