A Passive On-board Sense Avoid System For Tactical UAVs

摘要

The problem of detecting, sensing and avoiding other aircraft during flight is a crucial challenge, that has to be overcome before the civil aviation authorities permit unmanned aerial vehicles to fly in civil airspace. For manned aircraft this task is performed by the pilot. Therefore e. g. the FAA states in its directive 7610.4J that UAVs must provide an "equivalent level of safety, comparable to see-and-avoid requirements for manned aircraft" to operate in national airspace. Up to now, this defines the lower threshold of a sense-and-avoid capability for unmanned aerial vehicles. On the other hand there are several technologies providing a performance that is clearly beyond. Constraints come into play w. r. t. to restrictions on on-board space, power, weight and cost. Particularly for Tactical UAVs these limitations have a severe influence on performance. In close cooperation with RUAG Aerospace BGT has developed an approach for the RANGER UAV for an onboard detect, sense & avoid system able to detect intruding aircraft in an azimuth range of+/- 110° and +/- 30° in elevation. The on-board part of the system consists of several cameras and an image processing module able to detect and track multiple aircraft simultaneously in real-time. Whereas the system in a first stage displays and reports intruding aircraft in the ground control station in a second stage the on-board processing enables the computation of optimal escape trajectories and could therefore plan and execute autonomous evasion maneuvers via direct link to the autopilot.