Abstract The “ion-beam shepherd” is a contactless space debris removal concept, which implies that the shepherd satellite (SS) must be controlled to move at a certain small distance in front of a space debris object during the de-orbiting phase. As shown in recent studies, the strategy to control the relative motion of this formation using only one compensation thruster of the SS can significantly reduce propellant mass of the actuators. However, such a control system maintains a required relative position of the underactuated SS with a periodic error. The amplitude of this error is small for quasi-circular orbits, but it can be significant for eccentric orbits due to the time-varying behavior of the plant. Given that there are debris in non-circular orbits that need to be removed, this article investigates the feasibility of using only one compensation thruster to control relative position of the SS in eccentric orbits. Both time-invariant and periodic linear-quadratic regulators are examined for using as a controller of the SS. A periodic reference input of the regulator is designed to reduce the relative position errors and improve the efficiency of the ion beam impact on the space debris object.

中文翻译：

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偏心轨道离子束牧羊人卫星的相对控制

摘要 “离子束牧羊人”是一种非接触式空间碎片清除概念，这意味着在离轨阶段必须控制牧羊人卫星（SS）在空间碎片物体前方一定距离处移动。如最近的研究所示，仅使用 SS 的一个补偿推进器来控制该编队的相对运动的策略可以显着减少执行器的推进剂质量。然而，这样的控制系统以周期性误差保持欠驱动SS的所需相对位置。对于准圆形轨道，此误差的幅度很小，但由于植物的时变行为，它对于偏心轨道可能很重要。鉴于非圆形轨道上有碎片需要清除，本文研究了仅使用一个补偿推进器来控制偏心轨道中 SS 相对位置的可行性。时不变和周期性线性二次调节器都被检查用作 SS 的控制器。调节器的周期性参考输入旨在减少相对位置误差，提高离子束撞击空间碎片物体的效率。