Reliability and Availability of Ship’s Computer Systems Based on Manufacturer’s Data and Worksheets

摘要

Computer controlled systems play important role aboard ships. Failure of such systems due to some component malfunction can be with fatal consequences. It is important to assess reliability and availability of such systems and minimum redundancy to ensure maintenance planning, ordering of spare components and safety of the voyage with as little as possible redundant components. This paper deals with development of model for reliability and availability of the computer system, which consists of three components with hot standby. Markov chains model is used to analyse probability of failure. Matrix of transitions is set after model development. Transition matrix is used to develop differential equations for model simulation. System’s reliability is larger if the system is under constant maintenance and service, but it would not be available. Hence, the optimum between reliability and availability should be found. System’s maintenance is limited during the voyage and hot standby is necessary to ensure success of the voyage. This paper presents a framework for assessment of reliability and availability of computer systems based on components’ redundancy, and practical data about MTBF. Many versions of the shipboard computer systems can be evaluated using the presented framework.