Conquering Underground Mine without GNSS
Advanced Navigation, a world leader in navigation and autonomous systems, has successfully demonstrated a breakthrough in underground navigation, delivering high-precision positioning without reliance on fixed infrastructure or GNSS, in Europe’s deepest underground mine in Pyhäjärvi, Finland.
The Hybrid Navigation System, combining a Laser Velocity Sensor (LVS) with the Boreas D90 fibre-optic gyroscope (FOG) Inertial Navigation System (INS), achieved consistent sub-0.1% navigation error across multiple runs, without relying on any fixed positioning infrastructure, pre-existing maps, or external aiding.
Subterranean network
Says Joe Vandecar, Senior Product Manager at Advanced Navigation, “Maintaining precision over a 22.9km subterranean course in Europe’s deepest underground mine demonstrates a level of performance that few systems in the world can rival without any prior intelligence of the environment. These results prove we’re one step closer to unlocking scalable underground autonomy.”
Navigating the vast subterranean network of the Pyhäsalmi Mine poses significant challenges. Located 1.4 km underground with a 63 degree latitude, just two degrees below the Arctic Circle, where traditional systems fail, the mine is completely impervious to GNSS signals. Its repetitive, multi-level tunnel network creates a high risk of visual disorientation, while its metallic ores distort magnetic fields and scatter radio waves.
Reliable navigation
To overcome these conditions, mines typically rely on infrastructure-heavy solutions such as ultra-wideband beacons, Wi-Fi, 5G repeaters, or perception-based techniques such as SLAM (Simultaneous Localisation and Mapping) which require cameras. These methods are costly to integrate and maintain, slow to install, and often unavailable in hazardous or unmapped zones where reliable navigation is most critical.
Shifting to a truly resilient navigation system, with less dependency infrastructure offers a scalable alternative, enabling reliable navigation even in the most inaccessible or hazardous environments.
An inertial-centred architecture
Championing this architecture, the Hybrid Navigation System is centred on Boreas, a world-class FOG INS. Unlike conventional systems, Boreas doesn’t rely on GNSS or magnetic compasses. Instead, it uses ultra-sensitive FOG technology to detect the Earth’s rotation and determine true North, a process known as gyrocompassing to find the vehicle’s direction (heading).
To maintain and enhance this accuracy, the INS is fused with Advanced Navigation’s LVS. Using infrared lasers, LVS continuously measures the vehicle’s true 3D velocity relative to the ground. This real-time data is critical for correcting the gradual ‘drift’ that occurs in standalone inertial systems, enabling the Hybrid System to maintain precision over extended distances.
Adaptive algorithms
This integration is made possible with Advanced Navigation’s AdNav OS Fusion software. Using adaptive algorithms, it dynamically weighs the reliability of each sensor in real time. Together, these technologies form a resilient Hybrid System delivering precise, uninterrupted navigational data in extreme environments, without GNSS or fixed infrastructure.
Selected from over 90 global applicants, a demonstration of the Hybrid Navigation System was livestreamed from the Pyhäsalmi Mine in Pyhäjärvi, Finland, as part of the Deep Mining Open Call under BHP’s Think and Act Differently (TAD) programme.
Validated across five separate runs in complete isolation from external aids or maps, the Hybrid Navigation System repeatedly achieved an accuracy of better than 0.1% of distance travelled. This performance demolishes a barrier once considered fundamental to underground navigation. View the recorded livestream here.The Hybrid Navigation System is set for commercial release in late 2025.
