A Fast Obstacle Collision Avoidance Algorithm for Fixed Wing UAS

This paper presents a novel fast collision avoidance algorithm for navigation in 3D space of fixed-wing Unmanned Aerial Systems (UAS). This algorithm is aimed at increasing the ability of aircraft operations to complete mission goals by enabling fast collision avoidance of multiple obstacles. The new algorithm, named Flexible Geometric Algorithm (FGA), combines geometric avoidance of obstacles and selection of a critical avoidance start time based on kinematic considerations. FGA reduced computational time by 90% when compared to current waypoint generation methods for collision avoidance. The starting point for the avoidance time window is determined by collision likelihood. Using this algorithm, the (Unmanned Air Vehicle) UAV is able to avoid static and dynamic obstacles while still being able to recover its original trajectory after successful collision avoidance. Simulations for different mission scenarios show that this method is much more efficient at avoiding multiple obstacles than other methods. Algorithm effectiveness validation is provided with Monte Carlo simulations and parametric results. In addition, this algorithm does not have specific requirements on the sensor data types and can be applied to cooperative and non-cooperative intruders.