Load-sharing Fault-tolerance Flihgt Control Software Design For Small UAV

As small UAVs are widely applied and more and more complex functions, the increasing scale and complexity of flight control software, as core of the reliable flight control system, is facing serious challenges. In view of the miniaturization structure features, further research on a high reliability of flight control system is essential to the successful executing of flight control missions. In this paper, a futher research and design of a load sharing tolerance flight control software is launched on a flight control computer platform, which has high intergration embedded with dual-processor inprove the reliability of flight control system, based on fault tolerance technology.First of all, according to the hardware resource configuration and the software development environment of flight control system, the demand analysis is presented and the functions of software are summarized. Then the overall design scheme of the flight control software is put forward, and the software function modules partition and dual task assignments are completed by adopting the idea of hierarchical modular design.Secondly, combining with the functional and performance requirements, the flight control and flight management functions are designed through using soft bus architecture based on the design of telecontrol and telemetry modle, data fusion module, navigation module, control law module, control output module and dual-processor communication module. On the base, using the method of multiple fault detection by dual processor, the design of fault diagnosis and processing as well as the system reconstruction strategies are completed. Then software fault tolerance of the system is achieved.Thirdly, based on the realization of software design, combining with the Vx Works multiple task scheduling mechanism, the multiple task divisions and priority assignments of the flight control software are accomplished. The task scheduling strategies, task communication and synchronization mechanism are determined as well. The corresponding solutions to the existing conflict of resources visiting under the multiple task circumstance are proposed.Finally, with the semi-physical simulation environment, the flight control, flight management and fault tolerance function of the software are verified successfully. The results show that the dual computer fault-tolerant flight control software with load sharing type functions is effective, which indicates the designed software owns high performance, high practicability and reliability.