Modeling And Control System Design For A Small Unmanned Quadrotor

The small unmanned quadrotor is a kind of unmanned aerial vehicle,which can takeoff and land vertically,and its mechanical structure is simple and easy to maintain,so the small unmanned quadrotor has a very important military and civilian value.In recent years,with the new materials,micro-electromechanical systems(MEMS),miniature inertial measurement unit(MIMU)and UAV flight control technology advances,the small unmanned quadrotor has been rapidly developed,and has become a hot area of concern by major colleges and universities,research institutes,enterprises and institutions.At the same time,the small unmanned quadrotor is a complex system with multi-variable,strong coupling and non-linear characteristics,so the modeling and control of the small unmanned quadrotor has become a hot and difficult issue in the field of control.This paper first discusses the research status and development prospect of the small unmanned quadrotor.Based on the analysis of the structure and flight principle of the small unmanned quadrotor,the mathematical model of the small unmanned quadrotor is established based on the Newton-Euler equation,including rigid body kinematics model,rigid body dynamics model,control distribution model and dynamic system model.At the same time,the aerodynamic drag model of the quadrotor is analyzed and established,and the parameters of the moment of inertia and the dynamic system of the quadrotor are obtained by a series of parameter measurement experiments.And then the simulation platform of the quadrotor is built in the MATLAB/Simulink environment.To deal with the unmodeled dynamics,the uncertainty of the model parameters and the internal and external disturbances of the quadrotor,this paper proposes a control system design method of the quadrotor based on auto-disturbance rejection controller(ADRC)and the basic principles of ADRC are introduced in detail.In addition,this paper combines particle swarm optimization(PSO)with steepest descent method for ADRC parameter tuning,which makes the ADRC easier to implement and has wider applicability.By attitude angle tracking and position control,immunity and robustness analysis on the simulation platform,the results show that the ADRC controller has the advantage of fast response,small overshoot,strong anti-interference ability and good robustness.In order to ensure the stability of the quadrotor in the course of the actual flight,a new quadrotor control system is designed which combines the ADRC technology and fault-tolerant control technology.Based on the analysis of the fault type and fault-tolerant control technology of the flight control system,a LADRC passive fault-tolerant controller is designed for the system fault and the LADRC parameters are adjusted by HPSO.The performance of the controller is analyzed by simulation experiments,and the simulation results show that the designed LADRC fault-tolerant controller has good control performance in suppressing parameter uncertainties,external disturbances and fault-tolerant control of actuator faults.