连续小推力航天器自主导航及在轨参数标定

以连续小推力航天器为背景,提出了综合考虑星载加速度计和推力器在轨标定的自主导航方案。首先以精确姿态测量和引力梯度模型为标定参考信息源,建立了包含加速度计参数、推力器参数以及光压系数的完整参数测量模型;然后基于天文导航方法建立了自主导航系统状态模型和观测模型;表明各状态和参数的能观性后,采用了具备良好计算效率和鲁棒性的双重无迹卡尔曼滤波方法进行状态和参数联合估计。分析与数值仿真表明,该方法通过结合参数在轨标定直接提高了导航模型精度,在工程应用中具备可行性和有效性。

Autonomous Navigation and In-orbit Parameter Calibration for Continuous Low Thrust Spacecraft

Novel autonomous navigation scheme was proposed for continuous low thrust spacecraft with synchronized calibration on accelerometer,thruster and solar radiation coefficient of the spacecraft.Firstly,by selecting precise attitude measurements and gravity gradient model as reference information,the calibration parameter models was established and the observability was discussed.Secondly,system dynamics and measurement models were developed based on spacecraft celestial navigation methods with observability guarantee.Dual-unscented Kalman filter was then designed to estimate the calibration parameters and navigation system states in an error-robust and integrated manner.The proposed method has directly reduced the navigation model errors through in-orbit parameter calibration,making it preferable in feasibility and effectiveness.