This paper proposes partially norm-preserving filtering for a class of spacecraft in the presence of time-varying, but constant-magnitude maneuver. The augmented state Kalman filter (ASKF) is commonly used to track the maneuvering spacecraft with unknown constant propulsion; however, if the maneuver varies via time, the estimation performance will be degraded. To promote the tracking performance of the ASKF in case of time-invariant, constant-magnitude disturbance, the partially norm-preserving ASKF is developed by applying the norm constraint on the unknown maneuver. The proposed estimator, which is decomposed into two partial estimators and iteratively propagated in turns, projects the unconstrained maneuver estimation onto the Euclidian surface spanned by the norm constraint. The illustrative numerical example is provided to show the efficiency of the proposed method.

中文翻译：

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跟踪由恒定幅度摆动推进驱动的机动航天器

本文针对存在时变但幅度不变的机动的一类航天器提出了部分保范滤波。增强状态卡尔曼滤波器（ASKF）通常用于跟踪未知恒定推进力的机动航天器；然而，如果机动随时间变化，估计性能将下降。为了提高 ASKF 在时不变、恒定幅度扰动的情况下的跟踪性能，通过对未知机动应用范数约束来开发部分保范 ASKF。所提出的估计器被分解为两个部分估计器并依次迭代传播，将无约束机动估计投影到由范数约束跨越的欧几里得表面上。