Normal matrix design method for autonomous attitude control of spacecrafts

The natural properties of spacecraft attitude dynamics and the method for the design of attitude control based on natural properties were investigated for the in-orbit redesign and evaluation of the redesigned result in autonomous spacecraft systems The transfer function matrix of the flexible spacecraft was shown to be a normal matrix. Then diagonal dominance property of the inertia matrix was also analyzed. With the application of the above-mentioned two properties in the design of attitude control, robust stabilization conditions under the multiplicative perturbance and the inverse-additive perturbance were obtained respectively with these robust conditions, the normal matrix design methods for attitude control were given, and its robustness can be conveniently evaluated. The comparison of the two robust stabilization conditions shows that the latter is better than the former in view of the performance demand of different loops.