The electrostatic tractor has been proposed to touchlessly remove space debris from geosynchronous orbit by taking advantage of intercraft Coulomb forces. A controlled spacecraft (tug) emits an electron beam onto an uncooperative or retired satellite (debris). Thus, the tug raises its own electrostatic positive potential to tens of kilovolts, whereas the debris charges negatively. This results in an attractive force called the electrostatic tractor. Prior research investigated the charged relative motion dynamics and control of the electrostatic tractor for two spherical spacecraft and how charge uncertainty affects the relative motion control stability, but attitude effects could not be studied due to the two-sphere model. This work uses the multisphere method to consider general three-dimensional spacecraft shapes, and it investigates how the electric potential uncertainty and debris attitude impact the equilibrium separation distance between the two craft. The results show bounds for safe operations that avoid a collision. State regions are identified where the relative motion is particularly sensitive to potential uncertainty. The relative station-keeping performance using either higher- or lower-fidelity multi-sphere method models are compared to demonstrate that even a lower-fidelity multi-sphere method model can yield good results.

静电牵引器已被提议通过利用航天器间库仑力从地球同步轨道上无接触地清除空间碎片。受控航天器（拖船）向不合作或退役的卫星（碎片）发射电子束。因此，拖船将其自身的静电正电位提高到数十千伏，而碎片则带负电。这会产生一种吸引力，称为静电牵引力。先前的研究调查了两个球形航天器静电牵引器的带电相对运动动力学和控制以及电荷不确定性如何影响相对运动控制稳定性，但由于双球模型，无法研究姿态效应。这项工作使用多球体方法来考虑一般的三维航天器形状，并研究了电势不确定性和碎片姿态如何影响两个飞行器之间的平衡间隔距离。结果显示了避免碰撞的安全操作的界限。确定相对运动对潜在不确定性特别敏感的状态区域。使用高保真度或低保真度多球体方法模型的相对站位保持性能进行了比较，以证明即使是低保真度多球体方法模型也能产生良好的结果。