面向载荷运输的非锚定空间系留电梯轨道半径保持

Orbital Radius Keeping of Unanchored Partial Space Elevator in Cargo Transportation

本文的目的是在不使用推力的情况下保持空间系留电梯主航天器在货物运输时的轨道半径,为此,基于六自由度动力学模型,对系统平衡状态进行了分析,得到了一种新的自稳定修正律。在此基础上,提出了一种新的控制策略,仅通过调节电梯舱的速度,实现了主航天器的轨道半径保持,并抑制了系统摆动。基于所提出的控制策略,采用等比例收缩时域模型预测控制律进行了仿真校验。仿真结果显示了该控制策略的有效性。

An unanchored partial space elevator consists of one unanchored main satellite, one end body and a climber moving along the tether between them. This work aims at keeping the orbital radius of the main satellite in cargo transportation without using thrusts. A six-degree-of-freedom two-piece dumbbell model has been established. The influences of the main satellite’s orbit motion act on a partial space elevator in the cargo transportation are analyzed at the first time. The equilibrium states are studied, and the outcome leads to a new self-stability modified law obtained that anchors the main satellite. Based on the modified law, a novel control strategy is proposed to keep the orbital radius of the main satellite and suppress the libration in the cargo transfer period by regulating the speed of the climber only. A proportional shrinking horizon model prediction control law is used to implement the new control strategy in the case study. The simulation results validate the proposed control strategy.