Laser-aided INS advances dead-reckoning accuracy in GNSS-denied environments

Advanced Navigation has successfully demonstrated a hybrid solution for long endurance GNSS-denied navigation, proving that a software-fused inertial-centred architecture is the defining standard for autonomy. This advancement is achieved by integrating a strategic-grade fibre-optic gyroscope (FOG) inertial navigation system (INS) with a new class of navigation aid: a laser velocity sensor (LVS). The result is a fused hybrid architecture that delivers unprecedented precision and reliability in even the most challenging environments.

In today’s dynamic operational environments, relying on a single sensor technology (such as GNSS or IMU) is no longer viable. Missions increasingly take place in GNSS-denied, electromagnetically noisy and physically complex settings where traditional systems falter. In response to this, Advanced Navigation has developed a hybrid solution for long endurance GNSS-denied navigation.

At the centre of every reliable navigation platform is a trusted source of truth: the INS. Advanced Navigation’s FOG INS, which is sensitive enough to detect the Earth’s rotation, provides that foundation by delivering precise attitude. Complementing this, Advanced Navigation’s LVS uses infrared lasers to measure a vehicle’s ground-relative 3D velocity with exceptional accuracy and long-term stability. Unlike conventional sensors, LVS performs reliably on both ground and airborne platforms, as long as it maintains a clear line of sight to the ground or a stationary surface.

Beyond its role as a velocity aid, LVS also enhances navigation resilience by detecting GNSS spoofing. By comparing its independent velocity measurements against GNSS-derived velocity, LVS adds an extra layer of security to Assured Positioning, Navigation, and Timing (APNT) strategies.

AdNav OS Fusion draws on sophisticated algorithms to interpret and filter sensor data. The software is designed to dynamically weigh the input from each sensor, adjusting in real time based on reliability scores, environmental conditions and operational context. This ensures continuous, high-confidence state estimation even when signals are lost, degraded or distorted. This inertial-centred, multi-sensor approach delivers a step-change in GNSS-denied navigation performance, compared to traditional methods.

Trials to demonstrate capabilities

To validate the accuracy and resilience of the LVS Hybrid system, Advanced Navigation conducted a series of rigorous real-world driving tests. Across five trials, the system delivered exceptional performance with an average error per distance travelled of 0.053% compared to a GNSS reference.

At the starting point of the test, GNSS on the INS was disabled in the state estimation process, forcing the system into dead-reckoning mode. RTK GNSS was logged separately as a reference, enabling direct comparison between the computed dead-reckoning solution and a trusted position reference.

The driving tests included a 23km route around Canberra and a 19.2km loop through the Parliamentary Triangle. GNSS was not used at any point during either drive for heading or position. In both cases, RTK GNSS is shown as the red line, while the Hybrid system’s result is shown in blue.

The Hybrid system was also tested on a fixed-wing aircraft combined with a tactical-grade INS, achieving a final error per distance travelled of just 0.045% over a 545km low-altitude flight. These results highlight the system’s strong ability to enhance navigation performance in GNSS-denied or contested environments.

The future of navigation

“The world is evolving, and navigation must evolve with it. GPS is disturbingly vulnerable to challenging environments, harsh weather conditions and cyberattacks with rising threats of jamming and spoofing,” said Chris Shaw, CEO and co-founder of Advanced Navigation, a global leader in autonomous systems and navigation technologies. “The question isn’t if GPS will fail, but when. Operators need to build resilience now.” 

“This hybrid solution is designed with adaptability and reliability in mind. While others focus on individual components, Advanced Navigation champions a layered, inertial-centred, multi-sensor architecture, fused together by intelligent software. This approach can be updated or modified to adapt to harsh environments and mission requirements,” he added.

Robust navigation demands a layered, inertial-first and multi-sensor architecture – held together by intelligent software – that can adapt and scale to meet the unique demands of each mission. Embracing a software-defined nature, Advanced Navigation’s architecture means updates and enhancements can be deployed with minimal hardware disruption. This paradigm shift ensures truly resilient navigation for critical applications across defence, aerospace, robotics and autonomous systems.

About the laser velocity sensor

The LVS is a terrestrial adaptation of Laser Unit for Navigation Aid (LUNA), a space-grade navigation technology developed for autonomous lunar landings. LUNA enables reliable navigation in the harsh environment of space by providing precise three-dimensional velocity and altitude information relative to the Moon’s surface. The result of several years of R&D, LUNA is set to be demonstrated aboard Intuitive Machines’ Nova-C lander as part of NASA’s Commercial Lunar Payload Services (CLPS) programme. By leveraging the engineering insights gained from LUNA, LVS adapts space technology into an Earth-ready solution for terrestrial GNSS-denied navigation.

For a more in-depth look at the technology, read this white paper.