Visual-aided inertial navigation system for GPS-compromised flight paths

Inertial Labs, a VIAVI Solutions Inc. company, has launched a visual-aided inertial navigation system (VINS) that allows aircraft to maintain accurate flight paths when no reliable GPS/GNSS signal is available.

The launch comes as the U.S. Department of Transportation (DOT) reports an increase in GPS signal jamming and spoofing in North America and much of Western Europe. This affects commercial and military operations, with up to 700 global GPS spoofing and jamming incidences taking place daily. Events are especially concentrated around war zones, with Lithuanian airspace alone recording over 800 cases of GPS interference during the last three months of 2024. Also affected are the communications and emergency service sectors, which also rely on precise timing and geolocation.

VINS allows UAVs to achieve very long-range missions in the most GNSS-challenged environments. VINS uses a robust 3D vision-based positioning software from Maxar Raptor to estimate a vehicle’s absolute 3D position by applying PnP principles to compare patterns captured from an onboard camera (day or infrared) with satellite imagery-derived Maxar Precision3D maps.

In GNSS-denied environments, VINS has demonstrated the capability to maintain its flight path with a horizontal position accuracy of within 35m, a vertical position accuracy of within 5m, and a desired velocity accuracy of within 0.9m/s of the true location and velocity. It is also capable of holding heading to within 1° and pitch/roll to within 0.1°. With GNSS enabled, it can maintain a horizontal position of 1m, a sub-2m vertical position and a velocity of 0.03m/s, with a heading accuracy of 0.1° and a pitch/roll of within 0.03°.

The system is designed for operation at low altitudes. The comprehensive modular system incorporates processing and sensor modules, a GNSS or CRPA antenna, plus an air-data computer and a digital wind speed sensor, enabling operation with both fixed-wing and multi-rotor UAVs.

VINS can optionally be equipped with a COTS radio to be used for data as well as to provide absolute position in GPS-denied environments. An Iridium LEO GNSS and M-code/SAASM GNSS receiver are also obtainable.

The company recently launched its second-generation RSR Transcoder, featuring a GPS full constellation simulator, designed to provide assured PNT during military operations in degraded or disrupted space operational environments (D3SOE).

“VINS and the RSR Transcoder are truly groundbreaking when it comes to assured PNT in GPS-denied environments,” said Doug Russell, senior vice president of Aerospace and Defense, VIAVI. “Through strategic acquisitions, we’re uniquely able to harness resilient timing from Jackson Labs and accurate navigation from Inertial Labs and implement these with intelligent sensor fusion, holdover and dead reckoning to ensure reliability and security as well as ease of operation.”