ETS-VI ON-ORBIT SYSTEM-IDENTIFICATION EXPERIMENTS

System identification and attitude control experiments have been perfo rmed as part of a series of bus experiments on the Engineering Test Sa tellite-VI, which was launched by an H-II rocket in August 1994. The a ims of the experiments were to establish a pre-launch system dynamics modeling method, to evaluate typical on-orbit modal parameter identifi cation methods and to develop robust and precise attitude controller d esign technology for future large flexible spacecraft and large space structures, In the on-orbit identification experiments, the central bo dy of the satellite was excited by gas jet thrusters and the measured attitude and paddle accelerometer signals were downlinked by telemetry . In this paper, the identified parameters are compared with those of the pre-launch modeling and the accuracy of the pre-launch model is ev aluated.