Modeling And Linear Quadratic Servo Control Of Quadrotor UAV

Quadrotor UAV is a multi-axis aircraft, with four rotors to hover and capable ofvertical lift. As the quadrotor UAV′s small size、light weight、simple mechanicalstructure、easy to carry and can easily enter the variety of harsh environments humanis not easy to enter.It is used to perform aerial photography、movie viewing、real-timemonitoring、terrain exploration missions, making it have become a popular choice toresearchers.In this paper, using the quadrotor UAV platform, at first analysis of its principlesof flight, according to mathematical assumptions modeling the quadrotor UAV.Andthen transformed it into state-space model which can be controlled and establishedsimulation models in the MATLAB Simulink corresponding the UAV models. Then,designed the controller for the UAV based on the state space model. Controllerdesigned was take advantage of the research of the theory of linear quadratic optimalcontrol, the basis of this law on the control of posture and height were designedstabilizer. As the quadrotor UAV model is nonlinear, the design of control for highlystable servo control based on the linear quadratic nonlinear feedback input-outputlinearization controller, and compared the linear and nonlinear controllers simulation.In order to make the designed controller can realized in practice, controller mustbe discretized. Simulation results show that regardless of the linear or nonlinearcontroller with appropriate discrete sampling frequency the performance of thecontroller have little significant change.