Equal strength design method for a kind of whole-spacecraft isolator

Because of high vibration amplitude,large frequency bandwidth,and vibration with randomness in the mechanical environment of space launch,the improvement of safe factor is of high significance for the special high reliability requirement of space launch,especially for that of the whole-spacecraft isolator.In this paper,the equal strength beam theory is first introduced and the corresponding mechanical model is established for the whole-spacecraft isolator.First,in summing up the domestic and foreign whole-spacecraft isolators' structural characteristics,we established a statically indeterminate composite beam model.Then,based on the small deformation assumption,Mohr theorem and equal strength beam theory,the mechanical model between the isolator's structural parameters and performance parameters is developed.The design method based on equal strength is derived after the explicit non-uniform strength mechanical model has been given.The proposed method can directly computes the isolator's performance parameters by structural parameters,and can design the equal strength isolator with needed safe factor.Finally,two kinds of isolators have been designed and analyzed.The results show that the stress distributes much more uniformly in the isolator's bracket and the safe factor can be improved significantly.