Dynamic performance fluctuation of solid-lubricated rotating mechanism for intermittent operation caused by launch vibration load

Space mechanism is the key to success of long-term space missions. The service life of solid-lubricated space mechanisms is affected by various mechanical loads before in-orbit operation, among which the load caused by the launch vibration is the most severe one. Dynamic performance is an indication of the operating state of solid-lubricated mechanisms. The fluctuation of dynamic performances caused by the load of launch vibration is an unanswered but important question. In this paper, the fluctuation of dynamic performances of solid-lubricated rotating mechanisms for intermittent operation was studied by means of experiments and theoretical analyses. One group of rotating mechanisms for intermittent operation with solid-lubricated ball bearings were subjected to sine sweep tests and random vibration tests, followed by continuous operation test. The dynamic performance of mechanisms was obtained throughout all tests. The other group of mechanisms were studied with continuous operation test only for comparing the effects of vibration on the dynamic performance of mechanisms. At the same time, the sample moments of the dynamic performance of mechanisms were calculated and analyzed. The contact stress in the vibration tests was calculated by the Hertz theory. The fluctuation of the dynamic performances of solid-lubricated rotating mechanisms for intermittent operation caused by the load of launch vibration was then concluded with further discussion.