Self-Directed and Informed Forced-Landing System for UAV Avoidance of On-Ground Persons, Vehicles, and Structures

摘要

During a piloted forced landing in which the aircraft can no longer maintain level flight and is therefore forced to make an emergency off-airport landing, the human pilot continuously reassesses and updates the forced-landing plan with the objective of minimizing on-ground and onboard injury and damage. As information becomes available regarding vehicle health, descent capability, and the suitability of the surrounding forced-landing options, the human pilot assimilates the new information and refines the plan based on continuously minimizing risk. In the case of an unmanned air vehicle, this level of intelligent risk minimization is currently unavailable. Moreover, low-weight and low-cost design objectives for unmanned aircraft have resulted in a lack of propulsion and control redundancy, as well as unreliable communication links and an associated increase in incidents due to engine failure, control failure, and lost link.1 Safe integration of Unmanned Aircraft System (UAS) into the National Airspace System (NAS) will require an onboard capability for unmanned aircraft to accomplish the complex observation, understanding, and decision making that is required without assistance from a human operator. An advanced system capable of perception, cognition, and decision making is necessary to replace the need for a dedicated expert operator to ensure safety to persons, vehicles, and structures on the ground during UAS forced landings. Deployment of such a system would enable multiple UAS to be supervised by a single operator without compromising safety. The Self-Directed and Informed Forced Landing System (AutoFLS) emulates the continuous decision making process of a human pilot by assimilating available information and constantly reevaluating the forced-landing plan. Robust, onboard guidance and control maximize the capability of the impaired aircraft while executing the current plan. The system considers current vehicle capability, wind estimates, landing site and route risk, as well as the uncertainty associated with these factors.