The method of system reliability modeling based on Hybrid theory

Traditional system reliability model is more concerned about discrete failure events, without considering the impact on reliability by system´s continuous dynamic process. This paper presents a method of system reliability modeling based on Hybrid theory, which combines the continuous dynamic process and the discrete failure events together during the system, and make it easier to describe the impact on system reliability of the interaction of continuous and discrete behavior of the system. Firstly, Hybrid Automata model is extended, and the event correlation constraint is introduced to describe the conjunction relationship of failure in the modeling process. Secondly, based on an improved Hybrid automaton model, several kinds of modeling approach of the discrete failure and the continuous state interaction is given. In the simulation process, either the automatic switch of the failure state can be achieved by the real-time decision of the continuous state of the system; the mutations of continuous state caused by the discrete failure can also be described. The propagation of the discrete failure is considered at the same time. Finally, a hydraulic case is modeled by this method using MATLAB/State flow, and the results illustrate the validity of the method.