Implementation Of Safety Computer Platform Health Management Based On Hidden Markov Model

Safety computer platform of Communications-Based Train Control (CBTC) system, developed independently, uses the2×2-out-of-2redundant structure and COTS principle. Due to the limited hardware monitoring conditions and strong dependence to the supplier of COTS products, safety computer is unable to get state monitor based on hardware. Users can't understand the health status of safety computer comprehensively and accurately.Health management has been a technology which is widely used in the area of aerospace and weaponry in recent years to monitor the state and repair the failure of a system or component parts. According to the problems of safety computer in CBTC, the paper studies the health management technology of safety computer platform in depth such as state monitor and fault diagnosis, using the "soft" failures related to the hardware failures.First, this paper introduces the concept of Health Management and expounds the model with Condition-Based Maintenance as the breakthrough point. Hidden Markov Model (HMM) is introduced to the fault diagnosis of safety computer platform, because of the similarities between recognition algorithm and fault diagnosis and its successful application in the field of pattern recognition.Second, based on demand analysis of safety computer in CBTC, simulation safety computer platform of2-out-of-2redundant structure is designed using the common computers.Finally, state monitor and fault diagnosis of safety computer platform are studied in depth. According to the early fault not be aware, the study realizes the continuous online state monitor using HMM and simulating aging fault. For some platforms with low health index, the study realizes accurate fault diagnosis by establishing HMM diagnosis library.The implementation of health management based on Hidden Markov Model can well solve Condition-Based Maintenance problem of safety computer platform. It has certain reference value to health management study of other safety system.