The Research And Application Of Maintainability Allocation Method Based On Genetic Algorithm

The maintainability engineering accounts for the aspect of design characteristics in equipment maintenance problems, endows the equipment of good maintainability, and consequently improves system efficiency and reduces life cycle cost of the equipment. Maintainability allocation is an important part of the maintainability engineering, which is absolutely necessary and of high cost-effect. A rational scheme of maintainability allocation can make the system achieve the required maintenance targets with low cost-effectiveness, thereby avoiding the blindness in the design of equipment. However, because of ignoring life cycle cost of the equipment, it is very difficult to apply conventional methods of maintainability allocation to complex mechanical system that of very high maintenance cost. To satisfy the requirement of maintainability design of complex mechanical system, it is urgent to carry through deep research work on methods and technology of maintainability allocation.Via comprehensive investigation, this paper analyzed advantages and disadvantages of conventional methods of maintainability allocation, proposed a new method based on MGA, developed a software module of maintainability allocation and then applied it to the maintenance design of TBD234 diesel engine. The main work and contributions include the following aspects:1. Proposed a comprehensive trade-off model of maintainability allocation that based on life-cycle maintenance cost and MTTR on the ground of comprehensive analysis of conventional methods, and then solved the model by combining NSGA-II with decision-making method of false power vector. This model can overcome the disadvantage of ignoring maintenance cost of the equipment of conventional methods.2. Took diesel cooling system as an example, constructed the model of maintainability allocation, designed genetic operators, chose elite retention strategies, then simulated in MatLab environment using GA Toolkit, finally determined the scheme of maintainability allocation through the decision analysis method. Results show that the scheme proposed in this paper can achieve the trade-off between life cycle cost and MTTR appreciatively.3. Using Visual Studio2005 software platform, developed a software module of maintainability allocation which contains conventional methods and the new method proposed in this paper previously based on C#.net programming language, and then integrated it into MDIP.4. Analyzed the design characteristics and target of maintainability allocation of TBD234 engine; through fuel system LRU division, computed,analyzed and discussed applications of various methods of maintainability allocation on the diesel engine.