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Study on the reliability analysis method of the main active reflector system of FAST

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) will be the largest single dish radio telescope upon completion. As one of the three critical innovations of the FAST project, the active reflector system is composed of thousands of reflector elements, actuators etc. The reliability study on the active reflector system is of great importance. The paper introduces a reliability analysis method applicable in FAST active reflector system or other mechanical systems of similar scale. Firstly, based on the qualitative analysis of the main parts such as reflector elements, actuators and cable-net, simulations of the reliability of these parts are performed. Secondly, based on the simulation results, the Advanced-Mean-Value-first-order method is used for the reliability calculation. Thirdly, the weak aspects of each part are found using the results of qualitative analysis and quantitative calculation. Reliability tests are performed for the weak aspects of each part respectively. Finally, the qualitative analysis results, the quantitative calculation results and the reliability test results are integrated to obtain an assessment of the reliability for the active reflector system. The Fault Mode Effect Analysis (FMEA) and Fault Tree Analysis (FTA) tables are generated for reference of the design, construction, operation and maintenance of the active reflector system.