Attitude Tracking Control For The Quadrotor Via Output Regulation And Event Triggered Mechanism

As a typical multi-rotor unmanned aerial vehicle(UAV),the quadrotor UAV has significant research value and application prospects,due to its simple mechanical structure,strong operability and low cost.However,the problems of susceptibility to interference and limited communication resources caused by its structural characteristics have also been the hotspot and key points in the control of the quadrotor UAV.As the fundamental part of the study of the quadrotor UAV,attitude stable tracking control has attracted widespread attention over the years.Based on the output regulation and event triggered control,this paper designs the attitude control system of the quadrotor UAV and its formation.The specific work is as follows:(1)The hardware structure and motion mechanism of the quadrotor UAV are introduced.By appropriately selecting the coordinate system and force analysis,the nonlinear dynamic model is accurately established.Lay a theoretical foundation for the research on the attitude system of quadrotor UAV and its formations.The research framework for solving linear and nonlinear system output regulation problems is summarized,and the related lemmas and assumptions are introduced.(2)Aiming at the posture stability tracking problem of the single quadrotor with limited communication resources and susceptible to external interference,a single quadrotor attitude controller based on output regulation and event triggered mechanism is designed.First,the single quadrotor attitude system is appropriately deformed,and linear internal models and observers are introduced to establish an extended augmented system.Secondly,implement coordinate and input transformation to transform the problem,and transform the output regulation problem of the single quadrotor attitude system into the robust stabilization problem of the extended augmented system.Design a state-based event triggered control law and event triggered mechanism to solve the problem of robust stabilization of the extended augmented system.Through stability analysis,it is proved that the attitude system control signal is stable and bounded,and the event triggered mechanism has no accumulation point at the moment of triggering,which eliminates the Zeno phenomenon.Finally,numerical simulation and hummingbird experiments verify the effectiveness of the designed attitude controller.(3)Aiming at the distributed cooperative control problem of the multi-quadrotor formation attitude system,a distributed attitude controller based on output regulation and distributed event triggered mechanism is designed.First,establish a leader-follower formation system.Define the control signal of the leader UAV,and use the communication graph based on the directed spanning tree to realize the information interaction of the formation system.Secondly,in order to obtain the desired steady-state state and desired steady-state input of the following UAV,the adjacent quadrotor UAV and its own control signals are sampled.Two distributed linear internal models are introduced to establish an augmented system.Through coordinate and input transformation,the output regulation problem of the multi-quadrotor formation system is transformed into the distributed event-triggered robust stabilization problem of the augmented system.A state-based distributed event triggered control law and a distributed event triggered mechanism are designed to solve the problem of robust stabilization of the augmented system.Through stability analysis,the effectiveness of the distributed event triggered mechanism is proved.Finally,the simulation results show that the designed distributed controller can realize the coordinated and stable tracking control of the multi-quadrotor formation,effectively saving communication and computing resources.