采用信标的大型可展开天线指向控制方法

为提高大型可展开天线的指向控制精度,并适应喷气卸载等在轨工况,基于Craig-Bampton法建立了表征柔性天线指向的动力学模型,在此基础上提出了一种采用信标的大天线指向控制方法.该方法先基于卡尔曼滤波,对大天线的振动状态进行检测,若天线未出现明显振动,则通过信标敏感器修正天线指向偏差,同时引入星本体姿态敏感器以保证稳定性；若天线振动超过阈值,则仅引入星本体敏感器以衰减振动,直至天线未出现明显振动.最后利用瑟拉亚(Thuraya)卫星的在轨实测热变形数据进行了仿真验证.结果表明,在未受到喷气扰动时,大天线指向精度优于±0.02°,在受到喷气扰动后,系统可正确检测并切换跟踪输入.这说明,该指向控制方法在保证稳定性的同时,可以有效修正大天线指向偏差,并能适应在轨位保、卸载喷气工况.

Pointing Control of Large Deployable Antenna Based on Beacon

In order to increase pointing accuracy of the large deployable antenna and adapt to on-orbit conditions such as jet dumping,the Craig-Bampton modal synthesis was used in antenna pointing dynamic modeling,and a pointing control method based on beacon was proposed.By using Kalman filter,the flexible antenna vibration status was estimated.If the antennas do not vibrate obviously,the antenna pointing was adjusted by beacon sensors,and the stability was ensured by collocated attitude sensors.While the antenna vibration exceeds the threshold,only the collocated attitude sensors were induced to attenuate oscillation until vibration was attenuated.By using the in orbit thermal deformation testing data of the Thuraya satellite,the simulation results show that the antenna pointing accuracy without jet is superior to ±0.02°,and the vibration could be estimated correctly with the switch of tracking input after jet dumping.The results indicate that the antenna pointing error is adjusted with the guarantee of stability,and the influences of jet dumping and station-keeping are limited with the proposed vibration estimation method.