Open-source STM32 autopilot for long-range fixed-wing UAVs (SmartNavX)

Hello HN,

I’m Talal Al-Suhaimi, a control systems and embedded engineer based in Saudi Arabia. I’ve spent the last several months designing and testing an open-source autopilot system for long-range, fixed-wing UAVs — and I'm excited to share it with the community.

SmartNavX is a fully open-source flight controller firmware and hardware platform built on the STM32F405. It's designed to be lightweight, efficient, and modular — offering full-stack autonomy for fixed-wing aircraft without relying on expensive or closed-source autopilots.

Key features: Runs on low-cost STM32F405 (Blackpill or custom board) GPS-based autonomous navigation (waypoints, RTH, loiter, geofencing) Sensor fusion using IMU (MPU6050), barometer, and magnetometer with Kalman filtering Real-time telemetry via ExpressLRS UART (MAVLink-lite supported) Integrated smart BMS support for Li-Ion flight packs (voltage sag correction) Ground control compatibility (QGroundControl) Python CLI tool for live configuration and telemetry decoding Why I built this: I needed a reliable, long-range UAV platform for mapping and data collection in remote desert areas, but wanted full control over both hardware and firmware. Most COTS solutions are either closed-source or too expensive for experimentation. So I built SmartNavX to be:

Developer-friendly Easily hackable Hardware-agnostic Suitable for both research and field use Resources: GitHub: github.com/En-Talal-ALSohimiy/SmartNavX Flight demo (26km autonomous desert flight):

This project is still evolving — I'd love feedback from others working on UAVs, navigation, telemetry, or embedded systems. Contributions, suggestions, and collaborations are more than welcome.

Thanks for reading, – Talal Al-Suhaimi Control Systems & UAV Engineer