Design And Implementation Of UAV Formation Based On Ground Station System

Unmanned aerial vehicles(UAVs)are widely used and have many kinds.They are classified into two categories according to the configuration of flight platforms: Rotor and Fixed Wing.With the progress of science and technology and the increasing demand,the single UAV can not meet the needs of human beings in various fields because of its single task,low efficiency and high risk.The multi-UAV formation has strong synergy,good execution efficiency and task completion,these characteristics make it play a vital role in military,disaster relief and other fields.Based on leaderfollower formation control model,the feasibility design of controlling formation flight of fixed-wing UAV is realized in the self-developed ground station control system.Firstly,UAV track generation should be based on the requirements of real-time flight tasks.On the ground station system developed in this paper,aiming at the problem of UAV track planning,this paper proposes an algorithm that automatically generates each wingman track point by point from the system according to the long aircraft track points,which reduces the complexity of setting the task points artificially.Based on leader-follower formation control model,the formation model is established by setting the spacing and azimuth angle between individuals in the model,and the coordinate orientation of the wingman can be judged when the long aircraft is at a certain track point.In actual flight,the difference of turning radius will lead to the difference of flying distance between the two sides of the long aircraft.The advantage of this algorithm is that different planning algorithms are used for the two sides of the wingman track,and the track is optimized to solve the formation error caused by the different turning radius.In formation control,the Px4 open source firmware has realized the position control of four rotors.Based on the realization mode of position control of four rotors and the characteristics of fixed-wing firmware,this paper presents a method of track planning,supplemented by speed regulation,introducing the algorithm of guidance point cooperating with speed regulation to solve the formation control problem of fixedwing.Unmanned aerial vehicles(UAVs)locate and calculate the desired position of the pilot point,i.e.the bureaucracy,by means of the GPS positioning sent to the ground station under the mavlink protocol.The error of the actual position between the pilot point and the bureaucracy and the error of the speed of the long and the bureaucracy are calculated as the input of the PID control model.The speed adjustment algorithm of the bureaucracy is proposed to solve the formation reconfiguration problem when the UAVs deviate from the track.It is more conducive to the flight stability of fixedwing UAV.The position of the wingman is adjusted dynamically centered on the long aircraft,which improves the robustness of formation control.The last part of this paper is the detailed design of the ground station system which controls the formation flight of multiple UAVs,including the data structure design of each module unit of the system,the function and function execution flow of the main functions,and how to customize the mavlink message to meet the functional requirements.Finally,the formation flight task of UAVs is accomplished through the ground station system control.