Three-Dimensional Collision Avoidance Control Law for Aircraft Using Risk Function and Fuzzy Logic

Abstract

This paper proposes a new collision avoidance control law for aircraft. RCPA (Range of Closest Point of Approach), representing risk in the future, and TCPA (Time to CPA), representing current risk, are used as risk functions. Furthermore, fuzzy logic is introduced in order to achieve human maneuvering and to settle singular point and chattering problems that are discussed in previous studies. Avoidance strategy consists of four main phases, maintaining course, avoidance, parallel flight and recovery phase, and three transition phases. The parallel flight phase and three transition phases are introduced to achieve moderate avoidance and smooth phase transition, respectively. Simulation results show that the proposed control law settles the past problems and achieves smooth and adequate avoidance. This paper also discusses the fuzzy evaluation method.Key Words: Guidance and Control, Collision Avoidance, Fuzzy Logic Nomenclature x, y, z: inertial coordinate system $, , : relative coordinate system v: aircraft velocity, m/s : direction angle, rad : flight path angle, rad : angle between line of sight and relative velocity, rad !: angular velocity, rad/s R r : relative range between evader and intruder, m R os : offset range from original course, m

Fuzzy Sets in Earth and Space Sciences

“…The paper focused on the current application of fuzzy logic control, and an advancement designed to increase responsiveness with the architecture. Shioiri and Ueno [31] proposed a new collision avoidance control law for aircrafts. Range of Closest Point of Approach (RCPA), representing risk in the future, and TCPA (Time to CPA), representing current risk, were used as risk functions.…”

Experiment of Collision Avoidance Control Law with Information Amount Feedback Using Vehicle Model

“…Frazzoli et al have given a solution to the collision avoidance problem using centralized conflict resolution with the decentralized aircraft preferences [8]. Shioiri et al have treated the collision avoidance problem in three-dimensions for safer flight of an aircraft using the risk function and fuzzy logic [9]. Gates has proposed rule-based collision avoidance control strategies for real-time online collision avoidance [10].…”