Movement reliability analysis of umbrella antenna rotation joint

To the rotation joints in deployment mechanism of umbrella antenna used in satellite, the movement reliability has two parallel performance functions: the performance function according to rotation work and that according to rotation moment. By means of the random functional moment method and the second moment method for reliability analysis, corresponding to the beginning phase, outspreading phase and the phase that the net has pressing force, the expressions of two performance functions were established respectively to calculate the reliability. Finally, the change curve of the movement reliability of umbrella antenna outspread mechanism with outspreading angle was analyzed with an example. To the whole outspreading course, the reliability has the trend of first increase and then decrease, and the reliability of the beginning phase was smallest.