Study of the multi-excitation decoupling optimization method for the integrated structure of a high-resolution optical satellite

In this paper, the sensitive frequency band for distortion and blurring phenomena of the in-orbit satellite is studied and the results are supplements for existing studies and can provide an important reference for the study of micro-vibration. To contain the large-amplitude and micro-vibration excitation response in this sensitive frequency band, a multi-excitation decoupling optimization method is proposed for the integrated structure of high-resolution optical satellites. First, the equivalent dynamics models of the satellite with and without an vibration isolator are established. By deriving the functional relationship between satellite bus stiffness, vibration isolator stiffness, and vibration isolation efficiency, the design objectives can be decoupled and assigned to the vibration isolator and satellite bus in a more cost-effective way, respectively, while maintaining a low computation volume of the multi-objective and multi-variable system optimization. Then, the satellite system is optimized with the objectives of minimizing the large-amplitude vibration response in the launch phase and the micro-vibration response in the orbital operation phase using the NSGA-II genetic algorithm. Finally, the design is verified by ground experiments that it can fully achieve required technical parameters under multiple vibration excitations. This method has certain reference value for the design of complex structural systems of high-resolution satellites.