Mini-ROS: A Lightweight C++17 Robotics Framework

Mini-ROS is a compact, single-process, multi-threaded robotics framework that brings the essential concepts of ROS to small embedded systems. It is written entirely in C++17, avoids external dependencies, and is optimized for low latency and deterministic communication.

Its purpose is to deliver a clear software structure for robotics applications without requiring a full ROS installation, which is often impractical on lightweight controllers.

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Why Mini-ROS?

Modern robots require multiple components to run concurrently—sensors, control algorithms, estimators, actuators, safety checks. In a monolithic program, this becomes unmanageable.

Mini-ROS solves this by:

• Separating logic into Nodes
• Providing standard communication patterns (topics, services)
• Avoiding the network overhead of ROS 1/2
• Remaining small, deterministic, and fast

This makes it suitable for:

• Real-time control loops
• UAVs, mobile robots, small manipulators
• Robotics projects running on Raspberry Pi, Jetson Nano, or similar hardware

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Core Features

🔹 Topic-Based Pub/Sub

Nodes communicate via named topics:

• Publishers write messages to a topic
• Subscribers receive them asynchronously

Communication uses lock-free or low-lock thread-safe queues for minimal latency.

🔹 Services (Synchronous Request/Response)

Services allow structured, blocking communication between nodes. Example: a path planner responding with a computed trajectory.

🔹 Timers and Node Scheduler

Nodes support spin() loops or spinOnce(), handling:

• Topic callbacks
• Service callbacks
• Timer events

🔹 Real-Time Performance Tools

Included utilities:

• Stopwatch → measure callback durations
• Statistics → running average, variance, latency
• ThreadSafeQueue → high-speed message passing

These make debugging and performance validation easier.

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Architecture Overview

Mini-ROS uses a central MiniRosCore singleton for discovery. Once linked, nodes exchange data directly without going through the core.

Advantages:

• No serialization unless you add it
• No sockets, no DDS, no middle-layer
• Deterministic memory access

The framework is intentionally minimal. You keep full control of memory, threading, and timing.

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Project Structure

Mini-ROS/ ├── CMakeLists.txt ├── LICENSE ├── README.md ├── examples/ │ ├── perf_demo.cpp │ ├── service_client_server.cpp │ └── talker_listener.cpp └── mini_ros/ ├── common/ │ ├── Statistics.h │ ├── Stopwatch.h │ └── ThreadSafeQueue.h └── core/ ├── IMessage.h ├── IService.h ├── MiniRosCore.cpp ├── MiniRosCore.h ├── Node.cpp ├── Node.h ├── Publisher.cpp ├── Publisher.h ├── ServiceClient.cpp ├── ServiceClient.h ├── ServiceServer.h ├── Subscriber.h └── Timer.h

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Build Instructions

Requirements

• GCC ≥ 8 or Clang ≥ 6
• CMake ≥ 3.10
• Linux recommended (but works on Windows with MinGW or WSL)

Steps

git clone https://github.com/your-username/mini-ros.git
cd mini-ros
mkdir build && cd build
cmake ..
make -j4

Running the Examples

1. Publish/Subscribe Demo

./examples/talker_listener

Shows one node publishing data and another receiving it.

2. Service Client/Server Demo

./examples/service_client_server

Tests the synchronous request/response model.

3. Performance Benchmark Demo

./examples/perf_demo

Includes latency and throughput statistics.