💥 ROS Fault Injector

Chaos Engineering for Robotics — Battle-Test Your ROS2 Stack Before the Field Does

If your robot has never been tested under chaos, it has never truly been tested.

Why Chaos Engineering? • Features • Quick Start • Architecture • Examples

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🤔 Why Chaos Engineering for Robotics?

Your ROS2 system works perfectly in simulation. But the real world is chaos:

• Sensor wires vibrate loose → random spikes in /imu/data
• WiFi congestion hits → /cmd_vel packets arrive 300ms late
• Hardware glitches → entire /scan topic drops for 2 seconds

If you haven't tested these failures deliberately, you will discover them catastrophically. The ros-fault-injector lets you inject these exact failure modes into any live ROS2 topic — in a controlled, reproducible, configurable way.

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✨ Features

Fault Type	Description
🔊 Gaussian Noise	Adds realistic sensor noise to Float32, Vector3, Twist topics
⏱️ Latency Injection	Artificially delays message delivery (fixed or random)
💀 Message Drop	Drops messages at a configurable probability (0.0–1.0)
📦 Topic Replay	Re-publishes stale data to simulate a frozen sensor

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⚡️ Quick Start

# 1. Clone and build
cd ~/ros2_ws/src
git clone https://github.com/EngineerAbdullahBinZafar/ros-fault-injector.git
cd ~/ros2_ws
colcon build --packages-select ros_fault_injector
source install/setup.bash

# 2. Launch the injector on any topic (e.g., inject noise into /imu/data)
ros2 run ros_fault_injector fault_node \
    --ros-args \
    -p input_topic:=/imu/data \
    -p output_topic:=/imu/data/faulty \
    -p fault_type:=noise \
    -p noise_std:=0.05

# 3. Visualize the difference in RViz2 or rqt_plot
ros2 run rqt_plot rqt_plot /imu/data/angular_velocity/x /imu/data/faulty/angular_velocity/x

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📐 Architecture

flowchart LR
    A["/real_topic\n(Any ROS2 Topic)"] -->|Subscribe| B["🔥 Fault Node\n(ros_fault_injector)"]
    B --> C{Fault Strategy}
    C -->|noise| D["Gaussian Noise\nInjector"]
    C -->|latency| E["Latency\nBuffer"]
    C -->|drop| F["Probabilistic\nDropper"]
    D --> G["/topic/faulty\n(Degraded Output)"]
    E --> G
    F --> G
    G -->|Subscribe| H["🤖 Your Robot's\nControl Nodes"]

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🎭 Example Scenarios

Scenario 1: Test your navigation stack under sensor noise

# Inject 5% Gaussian noise into your LiDAR scan
ros2 run ros_fault_injector fault_node \
    --ros-args -p input_topic:=/scan \
                -p fault_type:=noise \
                -p noise_std:=0.05

Scenario 2: Simulate a congested WiFi link

# Add 250ms random latency to velocity commands
ros2 run ros_fault_injector fault_node \
    --ros-args -p input_topic:=/cmd_vel \
                -p fault_type:=latency \
                -p latency_ms:=250

Scenario 3: Test behaviour when GPS drops out

# Drop 40% of GPS messages
ros2 run ros_fault_injector fault_node \
    --ros-args -p input_topic:=/fix \
                -p fault_type:=drop \
                -p drop_probability:=0.4

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🤝 Contributing

See CONTRIBUTING.md and CODE_OF_CONDUCT.md.

Open Bounties:

• Support for custom message type injection
• YAML-based fault scenario files (e.g. scenario_wifi_failure.yaml)
• RViz2 overlay plugin to visualize active faults

📄 License

MIT License — See LICENSE for details.

👤 Author

Built by Engineer Abdullah Bin Zafar — GitHub · LinkedIn

If this saved your robot from a real-world disaster, drop a ⭐!