Some Problems In Formation Control Of Quadrotor

In the past decade,the quadrotor unmanned aerial vehicle(UAV)has attracted broad attention both in scientific research and business.Especially in recent years,with the more matured control technology of quadrotor UAV and the rapid development of multi-agent system control,the application prospects of group system formation are more and more extensive.As a special case of the agent,the quadrotor UAV has been widely used in multi-agent control.Both research institutes and commercial companies have begun to study the drone formation control strategy.The main research contributions of this thesis are as follows:(1)A flocking optimal sustainability formation control algorithm for quadrotor UAVs with virtual leader is designed.Firstly,under the undirected communication topology,the method of speed consistency algorithm,artificial potential function gradient and guided feedback term calculation is used to realize the swarm formation control of the quadrotor UAVs with virtual leader.Then,considering the disadvantages of undirected communication topology,such as high difficulty in communication and high noise,the undirected communication topology is changed into the optimal sustainable directed communication topology after realizing the flocking formation mentioned above,so as to achieve the optimal sustainable formation.Finally,the feasibility and effectiveness of the formation control algorithm is proved by matlab numerical simulation and Gazebo 3D simulation.(2)For the quadrotor UAVs system with one leader,the formation control strategy is designed in this thesis,where the states of followers form a predefined time-varying formation while tracking the state of the leader.Firstly,the dynamic model of the quadrotor UAVs is introduced,and the formation control system of the quadrotor UAVs is described.Then based on the relative information of adjacent quadrotor UAVs,a formation control protocol with a leader is proposed.Combined with the given dynamic model,the theoretical correctness of the formation control protocol is proved.Finally,the matlab numerical simulation results and the Gazebo 3D simulation results are given.(3)In this thesis,the formation control problem of three aircraft with switched communication topology is studied,and the formation control algorithm is designed.Combined with the formation feasibility constraint based on graph theory,the sufficient and necessary conditions for formation of a quadrotor uav system with switched communication topology are proposed.By solving the algebraic Riccati equation,a method of designing the formation control protocol is proposed,and the stability of the method is proved by the common Lyapunov stability theory.The obtained results can be used to solve the problem of target enclosing problem of a multi-quadrotor UAV system.Finally,the effectiveness and feasibility of the formation control protocol is proved by matlab numerical simulation and Gazebo 3D simulation.In this thesis,the autonomous robot 3D simulation environment Gazebo is introduced.The quadrotor UAVs formation 3D simulation platform is developed,which is based on Gazebo and Pixhawk.Through the platform,formation flight of quadrotor UAVs can be more directly displayed.The simulation results are more reliable and convenient for subsequent research and analysis.