L1 Adaptive Control for Wind Gust Rejection in Quad-Rotor UAV Wind Turbine Inspection

Abstract

This work presents preliminary results of the control method developed for autonomous inspection of wind turbines. High wind gusts are a major deterrent of outdoor Unmanned Aerial Vehicle (UAV) operations, in which, common classical control methods such as Proportional-Integral-Derivative (PID) control do not perform well. Therefore, more robust adaptive control methods must be employed. We propose the use of an L1 adaptive velocity controller that is capable of fast adaptation and guaranteed robustness while withstanding any disturbances encountered during flights. Considerable increase in performance of the L1 adaptive controller is demonstrated by comparing the proposed approach to a Linear Quadratic Regulator (LQR) method in simulation and a benchmark PID controller in several real flight experiments with added wind gusts