Integrated Semiempirical Methodology for Microvibration Prediction

Abstract

In this paper, a full methodology to deal with microvibration predictions onboard satellites is described. Two important aspects are tackled: 1) the characterization of the sources with a pragmatic procedure that allows integrating into the algorithm the full effect of the sources, including their dynamic coupling with the satellite structure; 2) the modeling of the transfer function source receivers with a technique named in this paper as the Craig-Bampton stochastic method, which allows prediction of a nominal response and variations due to structural uncertainties as accurate as full Monte Carlo simulations but at a fraction of the computational effort. The paper then includes a statistical study of the data from the structural dynamic testing of the five identical craft of the Rapid-Eye constellation to set the magnitude of the uncertainties that should be applied in the analysis. Finally, the computational procedure is applied to the new high-resolution satellite SSTL-300-S1 and the predictions compared with the experimental results retrieved during the physical microvibration testing of the satellite, which was carried out at the Surrey Satellite Technology Limited facilities in the United Kingdom

Experimental and numerical investigation of coupled microvibration dynamics for satellite reaction wheels

“…Note the number of elements defining the RWA dynamic mass matrix is dramatically reduced from 36 to only 8 elements, boxed in Eq. (9). In order to analytically and/or experimentally retrieve the dynamic mass of a RWA, direct measurements of the wheel accelerance matrix [31,40] are generally carried out.…”

Dynamic Mass of a Reaction Wheel Including Gyroscopic Effects: An Experimental Approach

“…SSTL300-S1 platform [3,4] and Skybox [5]), all carry vibration sensitive instruments on-board (e.g. high resolution cameras aiming to achieve 1m ground resolution), thereby, even displacements in the order of micro-meters of the instrument mounting interface may signicantly aect the light of sight of the instrument, dramatically reducing its performance.…”

Effect of Reaction Wheel Imbalances on Attitude and Stabilization Accuracy

“…The first is the saturation problem, which can be solved by auxiliary actuators such as magnetorquers. The second problem is the vibrations affecting spacecraft hardware, its flexible parts and overall dynamics [5,6], which might be crucial for some missions. One of the vibration sources is the RW imbalance.…”