Radar-visual navigation for all-weather approach and landing to vertiports

This paper presents an onboard multi-sensor navigation architecture to support approach and landing of rotorcraft in Urban Air Mobility scenarios. The proposed solution integrates an inertial measurement unit, a GNSS receiver, two cameras and a radar within an Extended Kalman Filter-based fusion framework. The integration of radar within the onboard architecture allows the system to operate in challenging visibility/illumination conditions, while also providing redundancy, and thus enhanced integrity, when the cameras are operating in nominal mode. Minimum requirements of the radar system are defined based on the constraints on the approach trajectory and ground infrastructure recently defined by the regulations. Then, the navigation architecture is detailed and its performance is evaluated through different simulations varying factors such as the cameras operation range and the number of ground scatterers exploited by the radar.