Performance Analysis and Design of an Obstacle Detection and Identification System

This paper reports the Performance Analysis and Design process for a non-collaborative anti collision sensor system to be installed onboard a High Altitude Long Endurance UAV that will be developed by the Italian Aerospace Research Center. First of all, a study on the required performances for the anti collision sensors was carried out. Requirements were critically reviewed considering flight dynamics models of the typical collision scenarios. The study included requirements on all sensor characteristics related to the anti-collision function such as resolutions coming from flying obstacle relative velocity and dimensions, field of regard, timing, and obstacle revisit rate. The requirements on sensor resolutions were discussed considering typical obstacle dimensions and flight envelopes. In addition, the dynamical correlation between sensor measurement rate and resolutions was modeled. The second step of the design process was to select sensors that fulfilled the estimated theoretical performances. The resulting sensor configuration included an active microwave anti-collision system, two visible cameras, and two infra-red sensors that allowed for increased performances in terms of angular resolution and measurement rate along with day/night and all weather capabilities. Subsequently, the system logic architecture was developed. The assigned system goal was to realize the detection, tracking, and identification of up to four obstacles that were simultaneously sensed in the Field of Regard. Standing the multiple sensor approach, sensor fusion architecture was developed for each one of the functions reported above. Multiple mode operation was determined depending on the number and on the type of sensors that could detect an obstacle at the same time. Flight tests will be carried out to demonstrate system capability with scaled performances by installing a selected set of sensors onboard a lightweight aircraft.