Research On Actuator Fault-tolerant Control Of Quad-rotor UAV

With the advantages of vertical take-off and landing,autonomous hovering and flexible control,quad-rotor UAV has gained wide attention in the military and civilian field.However,due to its working environment is complex and changeable,it's easy to go out of order in real life,which will lead to serious reduction of flight,and even result in system crash.So it has very important practical significance to study the fault-tolerant control of quad-rotor UAV.This paper is mainly aimed at fault-tolerant control of quad-rotor UAV with actuator failures.Firstly,the application of fault-tolerant control of quad-rotor UAV is briefly expounded,the structure and flight principle of quad-rotor UAV is expounded.The fault types and models of the actuator failures are expounded.The 6 DOF dynamic model of quad-rotor UAV is established.Secondly,fault-tolerant controller is designed for quad-rotor UAV with multiplicative failures.The 6 DOF dynamic model of quad-rotor UAV with multiplicative failures is built.To solve this kind of problem,as well as improve veracity of UAV system,adaptive fractional order sliding mode controller(AFOSMC)is designed.The simulation results show the validity and rationality of AFOSMC fault-tolerant algorithm.Thirdly,fault-tolerant controller is designed for quad-rotor UAV with additive failures.The 6 DOF dynamic model of quad-rotor UAV with additive failures is build.To solve this kind of problem,adaptive controller based on disturbance observer is designed.Regarding actuator failures,modeling error,outside interference as actuator failures,the estimations of the actuator failures are obtained by the limited-time disturbance observer and then adjusting parameters of the adaptive controller to ensure the tracking performance of quad-rotor UAV.Finally,two fault-tolerant algorithms are tasted in the Quanser UAV experimental platform.In this paper AFOSMC controller and adaptive controller which is based on observer are designed respectively.Fixed-point hovering experiments verify the practicability of the algorithms,in the process of experiment,multiplicative faults and additive faults are added.