摘要

Purpose - The purpose of this paper is to present an adaptive controller of nonlinear path following for a fix-wing micro-aerial-vehicle (MAV) in flight. The adaptive controller discussed in this work was able to successfully complete the flight tasks in complicated terrain, with improved trajectory tracking precision and flight quality.
Design/methodology/approach - The nonlinear desired trajectory was fitted by the method of fifth-order B-splines with a sequence of waypoints which are created and sent by the ground station. According to the relationship between the nonlinear desired trajectory and aircraft's flight path, the authors have built the relevant error equations of position and course under wind disturbances, based on the Serret-Frenet frame. The Lyapunov function can be constructed in virtue of the error equations and desired course function applying the vector field theory. On the basis of Lyapunov stability arguments, the authors have also constituted the course adaptive control law, which is converged asymptotically and stably.
Findings - According to the nonlinear desired trajectory fitted by the proposed adaptive control methods, the authors have carried out the flight tests experiments with various positions, courses and airspeeds of aircraft. The experimental results show a good path following, as well as under wind disturbances.
Practical implications - A new methodology for the nonlinear path following has been proposed, which is also proven to be promising for other special applications such as the path following in straight-line segment and orbit, etc.
Originality/value - The paper provides a novel realization method for accurate path following for MAVs. This method can also be carried out in many applications by a simple hardware.

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