Modelagem e controle de um microveículo aéreo: uma aplicação de estabilidade robusta com a técnica backstepping em uma estrutura hexarrotor

摘要

In this Thesis, the development of the dynamic model of multirotor unmannedaerial vehicle with vertical takeoff and landing characteristics, considering inputnonlinearities and a full state robust backstepping controller are presented. Thedynamic model is expressed using the Newton-Euler laws, aiming to obtain a bettermathematical representation of the mechanical system for system analysis and controldesign, not only when it is hovering, but also when it is taking-off, or landing, orflying to perform a task. The input nonlinearities are the deadzone and saturation,where the gravitational effect and the inherent physical constrains of the rotors arerelated and addressed. The experimental multirotor aerial vehicle is equipped withan inertial measurement unit and a sonar sensor, which appropriately provides measurementsof attitude and altitude. A real-time attitude estimation scheme based onthe extended Kalman filter using quaternions was developed. Then, for robustnessanalysis, sensors were modeled as the ideal value with addition of an unknown biasand unknown white noise. The bounded robust attitude/altitude controller were derivedbased on globally uniformly practically asymptotically stable for real systems,that remains globally uniformly asymptotically stable if and only if their solutionsare globally uniformly bounded, dealing with convergence and stability into a ballof the state space with non-null radius, under some assumptions. The Lyapunovanalysis technique was used to prove the stability of the closed-loop system, computebounds on control gains and guaranteeing desired bounds on attitude dynamicstracking errors in the presence of measurement disturbances. The controller lawswere tested in numerical simulations and in an experimental hexarotor, developedat the UFRN Robotics Laboratory