Dual Quaternion Based Fixed-time Integrated Attitude-position Tracking Control For The Tilt Quadrotor UAV

The position and attitude model of the traditional quadrotor UAV are usually established separately,and the corresponding control laws are designed respectively.However,with the rapid development of unmanned aerial vehicle(UAV)technology,quadrotor UAV is limited by weak maneuverability,short endurance time.And the "divide and conquer" control mode of position and attitude has certain limitations,which will lead to its inability to effectively carry out increasingly complex flight missions.In this context,it is of great theoretical significance and engineering value to study the integrated attitude-position control of tilt quadrotor UAV with high maneuverability.Tilt quadrotor UAV usually suffers from external disturbance and parameters uncertainty during the mission,which will have a negative impact on the stability of the control system.Therefore,in order to solve the above problems,this dissertation combines sliding mode control and fixed time control technology,and takes the position and attitude integration control of tilt quadrotor UAV as the core goal to carry out the research.Based on this,the main research content of this paper is summarized as the following four aspects:Considering the problem of integrated attitude-position modeling and control for the tilt quadrotor UAV,a six-degree-of-freedom(6-DOF)modeling and control method for tilt quadrotor UAV based on dual quaternion was studied.Firstly,a 6-DOF kinematics and dynamics model of a tilt quadrotor UAV is established under the dual quaternion framework.Then,on the assumption that there is no parameters uncertainty and external disturbance in the tilt quadrotor UAV,combined with dual quaternion and terminal sliding mode control technology,a fixed-time six-degree of freedom trajectory tracking control method is designed,which can realize the rapid tracking of the desired trajectory and attitude of the tilt quadrotor UAV.Considering the problem of the tilt quadrotor UAV control system under external disturbances,a non-singular fixed-time six-degree of freedom trajectory tracking control method which based on disturbance observer and integral terminal sliding mode technology is designed in view of the 6-DOF trajectory tracking and control problem for tilt quadrotor UAV with existence of external disturbance.Firstly,an auxiliary variable related to the state of the system is defined,and a fixed time disturbance observer is designed to estimate the external disturbance information in real time.Then,a fixed time six-degree-of-freedom trajectory tracking control method combining dual quaternion,integral terminal sliding mode control technology and interference reconstruction information is proposed which can effectively deal with external interference.Considering the 6-DOF trajectory tracking control problem of tilt quadrotor UAV with parameter uncertainties and external disturbance,a fixed-time 6-DOF tracking control method based on adaptive technology and non-singular terminal sliding mode technology was proposed.First,a fixed-time six-degree-of-freedom trajectory tracking control method based on dual quaternion and nonsingular terminal sliding mode technology is proposed for nominal systems without external disturbances and parameter uncertainties.Then,considering that the tilt quadrotor UAV is affected by external disturbance and parameters uncertainty,a 6-DOF adaptive control method based on immersion and invariant manifold is designed to solve the problem that the adaptive estimate deviates from the real value under the determined equivalent framework.The correctness and effectiveness of the above three trajectory tracking control methods of the tilt quadrotor UAV are verified from the following three aspects: First,the stability of the trajectory tracking control system of the tilt quadrotor UAV is proved by Lyapunov analysis method at fixed time;Then,according to the integrated attitude-position mathematical model of the tilt quadrotor UAV and the designed control method,numerical simulation is used to verify the effectiveness of the designed control method.Finally,in order to further verify the effectiveness of the above control method in the semi-physical simulation environment,the semi physical simulation model of the tilt quadrotor UAV was built by using Solid Works+Simscape,and the trajectory tracking control of the three-dimensional tilt quadrotor UAV was realized by the designed control method.