Research On Quadrotor Aircraft Control Method Based On Finite-time Control Technique

The quadrotor unmanned aerial vehicle(UAV)is a kind of vertical take-off and landing unmanned aerial vehicle,which can achieve precise hovering,flying indoor,low speed cruise and other missions.It has been widely used in civil and military field.Due to that quadrotor UAV is a typical under-actuated control system with multivariate,strongly coupling and nonlinearity,which leads to the fact that the design of controller is very challenging,how to achieve a high performance flight controller has always been the key problem in the control field.Finite-time control technology is a new kind of nonlinear control method,which has faster convergence rate and stronger disturbance rejection performance.Thus,it can significantly improve the performance of the closed-loop control system.In this paper,we first give a survey for the research situation of the quadrotor UAV and finite-time control theory.Then,the basic structure and flight principle of the quadrotor UAV are respectively introduced,and the system model of the quadrotor UAV based on the quaternion is given.Based on this,the tracking control problem for a single quadrotor and the formation control problem for multiple quadrotor are considered respectively.Different from the most existing results,which only guarantees that the closed-loop system is asymptotically stable,the proposed control law both achieve finite-time stable,i.e.,the system states converges to equilibrium in a finite time.Specifically,for the tracking control problem of a single quadrotor,based on the theory of homogeneous,a finite-time position tracking control law is designed.Based on the technique of adding power integrator,a finite-time attitude tracking control law is proposed.The position and attitude of the quadrotor UAV can both tracked the desired values in a finite time.For the formation control problem of multiple quadrotor,by using the finite-time consensus theory,a distributed finite-time formation control scheme is presented to ensure all quadrotor can converge to the desired formation pattern and flight along the desired trajectory.Meanwhile,based on Lyapunov theory,the rigorous proof of finite-time stability of the closed-loop system is given.The effectiveness of the theory is verified by Matlab simulation.At last,an experimental platform based on the ball joint for attitude control of quadrotor UAV is designed and built in this paper.The verification of the finite time control algorithm is carried out.The experimental results show that,compared with the PID control,the finite-time attitude control algorithm can not only improve the convergence rate of the closed-loop system,but also reduce the steady-error of the closed-loop system.