Safety Procedure Using Path Planning Methods for Tilt-Wing Unmanned Aerial Vehicles

This paper presents a safety procedure for tilt-wing unmanned aerial vehicles (UAV) considering flight dynamic constraints, geofences, and static obstacles. The proposed safety procedure ensures that the UAV remains in a safe flight state or is transferred into such a state, if the initial flight path cannot be flown as planned. This is accomplished by planning an emergency flight path to one of the predefined safety points periodically during normal operation using existing path planning algorithms. This emergency flight path is planned even before an error has occurred and is automatically activated in case of errors due to external influences, system failure, or defects. Once the safety point is reached, the flight system can remain in hover state or enter a transition to landing. Within this paper, the procedure is implemented for a tilt-wing UAV and offers a safety feature that is executed at regular intervals during flight.