Inflight path planning replacing pure collision avoidance, using ADS-B

Abstract

This paper proposes a method of collision avoidance planning using automatic dependent surveillance-broadcast (ADS-B) and dynamic programming (DP). It in essence allows air traffic control (ATC) within the cockpit for remote or uncontrolled airspace and is a step toward Free Flight. This paper reviews the approach to collision avoidance in the aircraft industry and to similar problems in other industries. DP is one solution method used in other industries for the problem of path planning to avoid collisions with fixed obstacles. The solution proposed here for the aircraft case uses DP applied to the moving obstacle case. The problem is first simplified by assuming fixed obstacles for the cost minimisation algorithms. These fixed obstacles are then moved with time and the minimisation process is started again. Although this method works well in most cases, situations can be constructed where this method fails, allowing a collision. A modified approach is proposed, where the movement of obstacles is included more explicitly in the cost minimisation algorithm. This modification allows solutions which are complete and ensures safe maneuvres and should be considered as an aid to the Traffic alert and Collision Avoidance System (TCAS).