Control System Design Of The Quad-rotor Based On GA-ADRC

Quad-rotor is a kind of small unmanned aerial vehicle(UAV)capable of vertical take-off and landing.The flight driving system consists of four motors powered by a battery.Due to its dexterous flying ability and excellent flight performance,the quad-rotor has become more and more popular in recent years.Quad-rotor has been widely used in many fields such as entertainment,agriculture,battlefield surveillance and so on.In terms of dynamics and kinematics,the quad-rotor is a typical underactuated system with four control inputs and six independent outputs(position and attitude).It is a nonlinear,multivariable,and strong coupled system.Besides,the control performance is also affected by the model accuracy and the precision of sensors,thus increases the difficulty of controller design.The active disturbance rejection controller(ADRC)is not highly dependent on the model accuracy of a system.It only makes use of the process error to eliminate the system error,thus consequentially being beneficial to decoupling control of a complex system.Therefore,in this paper,the quad-rotor aircraft is used as the research object,and the ADRC controller for the quad-rotor model is designed to solve many problems such as the uncertainty of modeling,the high coupling of the model and the sensitivity to external disturbance.The first chapter analyzes the quad-rotor aircraft structure and flight principle,sets up a mathematical as well as a control efficient model for the UAV,and then introduces the ADRC control principle.The second chapter introduces the commonly used quad-rotor sensor working principle of acquiring the attitude information,and describes the rotation matrix,Euler angles,quaternions,as well as the attitude algorithm process.The third chapter designs an ADRC-based controller driven by the data derived from the above attitude algorithm.In the fourth chapter,a four-rotor ADRC attitude controller based on genetic algorithm is designed to solve the problem of linear ADRC multi-parameter optimization.The flight experiments and numerical simulations show that the ADRC controller achieves better control performance for a quad-rotor.The flight process is stable and fast,insensitive to the disturbances.Furthermore,the genetic algorithm solves the problem of parameterization well,which makes the ADRC controller easier to implement.