Research On Key Technologies Of Multi-uavs Cooperative Formation Flight Control

With the development of modern military warfare,the requirements for the autonomous coordinated engagement of multi-aircrafts are getting higher and higher.Multiple unmanned aerial vehicles(multi-UAVs)coordinated formation control technology is the underlying technology for the UAV swarm.This paper takes multi-UAVs as the research object,aims at formation maintenance and obstacle avoidance issues,and focuses on improving the formation control precision and the ability of obstacle avoidance.It mainly includes the following aspects:(1)Based on a review of the research status of multi-UAVs formation control and obstacle avoidance at home and abroad,the existing problems and future directions of formation control methods are analyzed,and a relative kinematics model based on the deviation of spatial position is proposed.This model simplifies the relative motion of UAVs.In addition,an information interaction topology with five V-shaped formations was designed.(2)In the related research on formation control for the virtual structure method ignored the communication between vehicles,a virtual leader state estimation algorithm was designed.Each UAV acquires the status of the virtual leader from the “neighboring” UAV defined in the communication topology,and comprehensively estimates the status of the virtual leader,which can be considered as the guidance for its own flight.At the same time,a three-channel PID controller with linear mixer is designed to provide velocity,course and altitude control commands for the UAV.The simulation results show that the UAV formation can keep precisely.(3)Aiming at the issue of formation keeping and obstacle avoidance joint control,a method of obstacle avoidance control based on virtual structure and APF method is proposed.Because the traditional APF method has the problem of local minima and poor formation organization ability,we improve the APF function to get high precise formation and ability of obstacle avoidance.Finally,the simulation of five UAVs avoiding multiple obstacles was used to verify the effectiveness of the obstacle avoidance algorithm.(4)In view of the non-intuitive effect of numerical simulation of formation control and the poor realization of 3D virtual reality,a distributed visual simulation platform based on FlightGear is built.The system has intuitive virtual display of formation task process with fewer hardware resources.