关键词: 微振动, 飞轮, 遥感卫星, 结构动力学, 视轴误差

Abstract: In order to analyze the influence of the jitter on the high resolution satellites’ imaging quality, which is generated by the reaction wheel, a structural dynamic model is established to simulate the jitter effect of a high-resolution satellite on orbit. In addition, the line-of-sight (LOS) error of the optical imaging system is calculated under disturbance. The calculation results show that the critical modes of the LOS error are the 8th and 9th mode, respectively. Besides, the LOS error is deteriorated by the primary and second mirror to the largest extent, whose structural parameters can be optimized to improve the imaging quality of the satellite. To verify the accuracy and rationality of the structural design of the satellite as well as the optimization process of the jittering, an on-ground jitter simulation is performed on the prototype of the satellite, whose attitude control system is designed with the offset momentum. The actual on-orbit speed is simulated by the Z/Y axis reaction wheel on the satellite, and then the jitter is obtained when the prototype is under suspended and fixed boundary conditions, respectively. Finally, we can make a comparison between the calculation and simulation results of the angular displacement of the satellite’s jitter, and it indicates that the relative error α is 11.13%, and the absolute value is 0.009 94 arcsecond. With a value less than 0.01 arcsecond, we can safely draw a conclusion that the imaging quality of the remote sensing camera is not degraded by jitter. This paper provides a reference for the jitter design of the optical remote sensing satellites.

Key words: jitter, reaction wheel, remote sensing satellite, structural dynamics, line-of-sight error