INTELLIGENT AGENT FOR AIRCRAFT COLLISION AVOIDANCE

way to obtain optimal traffic avoidance trajectory. The trend of air traffic system is heading towards a free flight environment. Free flight offers greater flexibility in planning for flights than the current air traffic control and management system. In free flight, operators are allowed to fly under Instrument Flight Rules and choose their own flight path and speed at real time. Some of the requirements to make free flight environment feasible include aircraft collision avoidance agent, also known as the traffic agent. One widely accepted concept of aircraft to aircraft communication for free flight environment is Automatic Dependent Surveillance Broadcast. In this paper, the focus is on constructing a traffic agent, utilizing aircraft to aircraft information, for an autonomous flight management system. The agent includes a traffic conflict detection module and collision avoidance module. The method used by the modules is a combination of knowledge base expert system and optimal control. The expert system is the primary decision maker and determines the appropriate actions required for conflict detection and avoidance. Optimal control is used to generate the optimum avoidance trajectory that adheres to the criteria assigned by the expert system. Results of a test case presented in the paper demonstrate that the combination of the two methods provides an efficient and effective