Research On Hierarchical Formation Control And Adaptive Communication Algorithm For UAVs

Unmanned aerial vehicles have been widely used in recent years.As one of the emerging frontier research fields,unmanned aerial vehicle formation can improve the formation's cruising range,reduce task execution time and improve mission success rate by making full use of the performance advantages of multiple unmanned aerial vehicles.And formation can avoid restrictions on mission execution capability and range of single unmanned aerial vehicle.In the current research on the formation of unmanned aerial vehicles,most of the research focus on the small-scale formations.There is a lack of research on the large-scale formations.In addition,there are relatively few studies on inter-machine communication in the formation network.Especially in the unmanned aerial vehicle cluster scenario,there is a lack of research on the communication overhead of the inter-machine self-organizing network.Therefore,this thesis studies the formation maintenance problem in the formation of unmanned aerial vehicles and the inter-machine communication overhead in the cluster.The main research is as follows:Firstly,this thesis proposes a layered hierarchical unmanned aerial vehicle formation control model based on bee colony bionics,which is adapted to large-scale formation.The model divides the entire formation system into several sub-bee colonies.The sub-bee colony is controlled by the lead unmanned aerial vehicle,and the centralized maintenance algorithm is adopted.The distributed maintenance algorithm based on geometric structure is adopted between the sub-bee groups.The lead unmanned aerial vehicles of each subgroup exchange their local geographic information and adjust their speed.And the formation control among the sub-bees has been completed.Then,this thesis proposes an inter-machine broadcast period adaptive algorithm for the problem of the ad hoc network communication overhead between the lead unmanned aerial vehicles.Based on fuzzy logic,the algorithm uses the formation stability and its change degree as the input of the fuzzy system,which can adaptively adjust the broadcast period of the geographical location message.Because the algorithm can dynamically adjust the packet broadcast period according to the stability of the formation,the communication overhead of the ad hoc network can be effectively reduced.Finally,the thesis validates the effectiveness of the formation maintenance algorithm and the inter-machine broadcast period adaptive algorithm by simulating and analyzing the unmanned aerial vehicle formation and communication system.The simulation results show that the proposed algorithm can effectively reduce the formation control cost,improve the formation maintenance accuracy and reduce the broadcast communication overhead of the inter-network self-organizing network.