Three dimensional fuzzy carrot-chasing path following algorithm for fixed-wing vehicles

Over the past several years, Micro Aerial Vehicles (MAVs) have received considerable attentions due to many useful applications in military and civil missions. Applications such as search and rescue, mapping, and surveillance require the MAVs to autonomously follow a predefined three dimensional path. Because of unavailability of the pilot during a mission, it is necessary to use autopilot systems. In this paper a parametric path following algorithm is designed and then implemented on a simulated nonlinear six-DoF MAV. For designing the path following algorithm, first, two-dimensional (2D) carrot-chasing algorithm is modified to a 3D algorithm. Then a 3D path following algorithm is presented using a combination of the carrot-chasing geometric algorithm, fuzzy logic and genetic algorithm optimization method. It is concluded that adding a fuzzy system to the carrot-chasing algorithm, improves its performance significantly. Also, for comparison, two other 3D carrot-chasing algorithm and 3D vector field method are designed and simulated. Finally, by considering a control system for the simulated MAV, a comparison among the three path following algorithms is done. Wind as an external disturbance is applied to the MAV. Simulation results show significant superiority of the proposed 3D fuzzy carrot-chasing algorithm over both the carrot-chasing and vector field methods.