Time delay is a novel celestial navigation measurement that can provide the distance information of the spacecraft relative to the nearby celestial body. Combining time delay measurement with traditional star angle measurement can greatly improve navigation performance. However, the navigation accuracy will be affected by the ephemeris error of the nearby celestial body. To solve this problem, this article adds the position and velocity of the nearby celestial body to the state vector and estimates them online. The estimated values are used to replace the ephemeris data of the nearby celestial body in the measurement model. Besides, an event-triggered implicit unscented Kalman filter (IUKF) is proposed to reduce unnecessary calculation and shorten the running time. Simulation results indicate that the position error and velocity error of the proposed method are reduced by about 61% and 67% compared with that of the traditional time delay/star angle integrated navigation method (TDSA), respectively. The running time of the proposed method is reduced by about 88% compared with that of the TDSA with the augmented state (AS). In a word, the proposed method can greatly reduce the running time while maintaining high navigation accuracy.

中文翻译：

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基于事件触发隐式无迹卡尔曼滤波器的时滞/星角组合导航方法


时延是一种新颖的天文导航测量方法，可以提供航天器相对于附近天体的距离信息。将时延测量与传统的星角测量相结合可以极大地提高导航性能。但导航精度会受到邻近天体星历误差的影响。为了解决这个问题，本文将附近天体的位置和速度添加到状态向量中并在线估计。估计值用于替代测量模型中邻近天体的星历数据。此外，提出了一种事件触发的隐式无迹卡尔曼滤波器（IUKF）来减少不必要的计算并缩短运行时间。仿真结果表明，与传统时滞/星角组合导航方法（TDSA）相比，该方法的位置误差和速度误差分别降低了约61%和67%。与具有增强状态（AS）的TDSA相比，该方法的运行时间减少了约88%。总之，所提出的方法可以在保持较高导航精度的同时大大减少运行时间。