Evaluation of ground and orbit microvibration of OICETS

The microvibration excited by on-board instruments is considered as a major factor of pointing stability deterioration. Therefore it is important to estimate the influence of the microvibration on pointing stability before the launch. In this paper, the ground test data obtained by using OICETS MTM (Mechanical Test Model) and in-orbit measured data obtained by on-board accelerometer (MVE: Micro Vibration Equipment) are analyzed. Analyzing these data with appropriate assumption, the transfer characteristics from main disturbance sources to MVE are calculated in both ground and in-orbit cases. As a result, similarity between the ground test data and the in-orbit data is evaluated, and the effectiveness of the ground test in predicting in-orbit microvibration environment is verified.