Reliability Evaluation Of Airborne IMA Partition Software Based On Petri Nets

Integrated modular avionics system(IMA)uses the resource sharing framework,the original line replaceable unit(LRU)resides in the form of software within the IMA system,reduces the coupling between the planes each function.However,resource interaction exists among the partition software in the IMA system,which makes the IMA system have obvious dynamic characteristics and fault propagation characteristics.Therefore,it is necessary to study the reliability quantitative evaluation model and quantitative evaluation method of the partition software of the IMA system,and carry out an effective quantitative evaluation of the reliability of the partition software.The main work of this paper includes two parts: Firstly,this paper establishes a single partition IMA system software reliability quantitative evaluation model,studies the factors that affect the reliability of the partition software and the degree of influence of each factor on the reliability of the partition software of the IMA system.Secondly,this paper studies the conversion method of logic gates in dynamic fault tree model to EDSPN to evaluate the reliability of the multi-partition software of the IMA system.Taking the display function of IMA system as an example,the reliability quantitative evaluation model of multi-partition software of IMA system is established.The failure propagation rate of IMA system is obtained by using Time NET4.4 simulation software,which provides a good model basis for analyzing the reliability of IMA system partitioning software.The experimental results show that the average time of error detection by health monitoring and fault management,the average time of HOT＿START and MTBF of the partition software have great influence on the reliability of the partition software.The increase of AFDX and MTBF of MMU has little effect on the reliability of IMA display system.