INPUT SELECTION FOR A 2ND-ORDER MASS PROPERTY ESTIMATOR

A strategy is developed for selecting online the attitude control jet firings to be commanded during the mass property estimation phase of the operation of any asymmetrical rigid satellite. Using symbolic manipulation, an effort is made to develop a selection strategy that accelerates convergence by maximally decreasing the change in the covariance of the estimation error at each time step. These results, which are too complex for online implementation, motivate a suboptimal direct search strategy. Examples of mass property identification are then demonstrated on a high-fidelity simulation of the Space Shuttle. The results indicate that the suboptimal strategies yield significant reductions in the time to convergence for the mass property estimates and in the cumulative fuel usage relative to a typical predetermined jet firing sequence.