On-Orbit System Identification Experiments of the Engineering Test Satellite-VIII

Abstract

This paper presents the results of on-orbit system identification of the Engineering Test Satellite-VIII (ETS-VIII), which was launched by the H-IIA Launch Vehicle No. 11 in December 2006. On-orbit system identification experiments were performed using data acquired during normal operations in the initial check-out phase, such as station acquisition and wheel unloading. The satellite's unconstrained modes were identified using attitude rates and data from accelerometers located on the main body, solar array paddles and large deployable antenna reflectors at various solar array paddle angles. In addition, the constrained modal parameters of the solar array paddles and large deployable antenna reflectors were estimated for comparison with the analytical model.