Research On Fault-tolerance Control Of Quadrotor Unmanned Aerial Vehicle

Quad-rotor aircraft are used in various fields,it is because its own structural characteristics,such as simple structure and lightweight.However,quad-rotor aircraft also has many complex characteristics,for example,strong coupling,overdrive and other characteristics;it becomes difficult when we want to use it in different fields.When the actuator has failures,the attitude of the aircraft is more difficult to control.Therefore,the problems of actuator failures have been a hot research topic in quad-rotor attitude control system.The quad-rotor aircraft with fault-tolerant control system is characterized by good security and reliability which help to promote the practical application and further development.Considering that the quad-rotor aircraft will have external disturbances during the flight,if the actuator fails in this case,proposing adaptive fault-tolerant control algorithms,and a state feedback controller based on regional stability is designed,research achievements in this thesis have offered a useful thought to improve the security and reliability of the system and the main contributions of thesis can be summarized as follows:First of all,the development of the fault tolerant control was outlined and expounded the analysis of the four rotor aircraft development at home and abroad,and in order to model,introduce Newton-Euler's formula and Lagrange Euler equations,and according to the linear model design the controller,the system of nonlinear model is derived and simplified into a linear model.Four rotor aircraft system model was simplified appropriately,because four rotor aircraft in flight was susceptible to interference problems,in various control methods,finally model reference adaptive algorithm was chose,then designed the disturbance compensation law and parameter adaptive law.And is verified in simulation.The adaptive compensation controller designed in this paper can solve this problem well and can satisfy the condition.Actuator fault has a variety of forms,death and partial failure is common in these faults,this paper put forward the direct adaptive fault-tolerant control.The algorithm has advantage in the external disturbance compensation and compensation of actuator failures,at the same time this controller can accurately track the attitude angle.For variant fault of actuators,this kind of failure is more common in practice,using the state feedback fault-tolerant controller,this controller is based on the analysis of the regional stability,as well as the performance of the system is optimized.Compared with LQR controller in MATLAB/SIMULINK simulation,the performance of the former is better after analyzing the results.At last,the research results of the quad rotor fault-tolerant control are proposed by the subject,the imperfections are analyzed and the next step is expected.