Design And Realization Of Military Vehicles Engine Diagnostic System Based On Fuzzy Recognition Of Petri Nets

Military vehicle takes the biggest proportion of lage equipments and is used most widely among troops. It is difficult to find the factors that account for performance failures for the engine is at the very core of a vehicle body, whose failing features amount large. Due to its structrural complexity and changeable working condition, failure rate of vehicle is on the top among military euipment.The personnel who manage and use military vehicles, change in a big way. Because service age is limited and personnel's fluidity is very strong, some experience's technical personnel may be face with demobilizing and changing career. The conventional failure diagnosis method based on the artificial experience and the skill has the empeiria and the professiona. The inexperienced personnel can't quickly determine and deal with failure. Therefore, determining the specific failures timely, rapidly, accuratly and making vehicle maintenance properly is an important guarantee for the army troops.This thesis develops a new failure-diagnosis system for military vehicle using Microsoft Visual C# under Windows.NET Framework. Petri fuzzy recognition and fault tree analysis theory are used and some typical military vehicles are taken as example to track common modes of vehicle failures, e.g. CA1092, CA142, EQ246, Changfeng Cheetah, Jetta.This thesis makes an emphasis on the introduction of basis for Petri fuzzy recognition and fault tree analysis theory, then make a study on the engine failures, which will datumize and simplify the failure identification process.Implementation steps and specific algorithm code are stated for every module in the system design section. System consists of three modules:User Management Module, Diagnosis Management Module, Symptom Search Module. Empirical statistics, experts weighting, comprehensive weighting, and fault tree analysis theory are applied to identify vehicle engine failure, then reults are saved as figures and tables to provide imformation for further improvement of structure, optimization design, appropriate manufacturing and operation.The final system diagnostic data with the unit detailed records of vehicle maintenance vehicle unit to compare the results of basic grass-roots level to meet the maintenance requirements.