Modified Constrained Wavefront Expansion Path Planning Algorithm for Tilt-Wing UAV

This paper presents a path planning algorithm for tilt-wing UAV that considers the flight dynamic constraints while planning the path. Being able to perform thrust-borne vertical take-off and landing as well as efficient wing-borne flight, tilt-wing aircraft offer multiple benefits in unmanned aerial vehicle applications. Applications that involve flying in airspaces not used exclusively by the tilt-wing UAV require the ability to avoid collisions with other manned and unmanned airspace users to ensure reliable and safe operation. Known approaches for collision avoidance either do not consider flight dynamic constraints during the path planning or use avoidance controllers instead of a planned path. The presented algorithm modifies the Constrained Wavefront Expansion (COWEX) algorithm to estimate the movement of the tilt-wing UAV as well as the intruder aircraft to be avoided at each planning step. This allows the modified COWEX algorithm to expand its avoidance capabilities from only static obstacles to moving aircraft. The algorithm is implemented for a simulated tilt-wing UAV and validated by solving a variety of standard and non standard avoidance scenarios.