Research Of Robust Control For A Quadrotor UAV With Nonlinearity And Multiple Variables

Quadrotor helicopters, have simple mechanical construction and low cost, are widely used in military, industry, education and custom field. At present, four-rotor controllers are designed based on PID model, and debugged through experiment and simulation. Thus, this paper is aimed at creating the mathematica models of actuators and the body of the aircraft, and carry out the controllers on account of optimal control theory.Fisrt of all, this paper introduces the principle and model of rotor, aerodynamic simulation based on lattice Boltamann and experiment method of rotor. It analyzes the accuracy of the model, the usability of the simulation and the areodynamic per- formance of the rotors with different numbers of blades but same blade shape. A refined formula is proposed to describe the transient state when the angular speed of the rotor is changed.Secondly, the well known equations of the DC motors is quoted to achieve the relationship between the duty of PWM wave and anguler velocity. A algorithm is putted forward to calculate the key parameters of the DC motors.Thirdly, the controllable of multi-rotor helicopters is discussed based on the dy- namics model which is established through theoretical mechanics. The moment of inertia of the quadrotor which is texted in this paper is calculated by related equations.In the consideration of the actual conditions, the dynamics model, mentioned above, is simplified into a linear model.At last, inner and outor controllers are designed based on the kinematics equation and the flight characteristics. Every controller's output is limited because the thrust generated by rotor is finite. Based on H? control theory, the controllers, used for texted quadrotor, are achieved and confirmed by experiment.