Research Of Redundancy Management And Fault-tolerance Technology Based On Dual Redundancy Flight Control Computer

Flight control computer is the core of UAV flight control system,and its safety and reliability is the key to ensure the normal flight of UAV.Redundancy management and fault-tolerance technology can not only improve the safety and reliability of flight control system,but also maximally reduce or even eliminate the impact of failure on the normal operation of flight control system.Based on the example of the dual redundancy flight control computer hardware,this thesis studies the fault-tolerance strategy and designs the flight control software.Firstly,this thesis analyses the overall requirements of the dual redundancy flight control computer and determines the redundancy features to meet the design requirements.Meanwhile,based on the characteristics of ?C/OS-?,the overall design requirements of flight control software is put forward,redundancy management solutions and the overall design strategies are defined.Secondly,failure mode analysis,fault detection and diagnosis,fault handling and reconstruction,and system unit recovery are carried out from three aspects of the central control unit,bus unit and interface unit.Among them,three methods of fault detection and diagnosis about the central control unit is presented based on the combination of heartbeat detection and checkpoints detection,software tasks running status auto detection and the joint algorithm of threshold improved SPRT;Strategies of bus channel detection and bus node detection are proposed for the bus unit;For interface unit,data update rate method,independent reference source detection and input and output circuit method are put forward.The fault disposal and recovery strategy is designed to realize function of the system.Then,according to the concept of function modularization of flight control software,we can divide and schedule software tasks,complete the development of system flight control and management module,redundancy management module and fault-tolerance strategy module.Finally,the semi-physical simulation environment is build to verify the fault-tolerance strategy including the central control unit,bus unit and interface unit,and the fault injection software is developed accordingly.The simulation results show that the function and performance indexes meet the expected design requirements.