基于环境力矩的大型航天器零燃料动量卸载技术研究

This project presents a method for zero-propellant momentum-unloading via environmental torque(gravity gradient torque and aerodynamic moment) .Firstly, the attitude model is established for spacecraft to reveal the complex momentum transfer characteristics and rules of the space environment, the spacecraft body and the control moment gyro in the attitude control task. Secondly, based on infinitesimal analysis, a method for calculating aerodynamic force / torque of the complex configuration of spacecraft is established. Thirdly, the attitude model of the large spacecraft is linearized on the torque equilibrium attitude which is acquired by the adjoint method. Finally, based on the polytopic representation approach, the momentum-unloading task is presented under the restriction of attitude angle and attitude angular velocity.. This project is of great value to extend the application ability of control moment gyro, to reduce the propellant consumption of spacecraft, and to extend the orbital lifetime. This project is of great significance to the construction and maintenance of the large space station in the future.

本项目研究一种利用环境力矩（重力梯度力矩和气动力矩）进行动量卸载的方法以实现零燃料消耗。首先，分析空间飞行器姿态动力学特性，揭示空间环境、飞行器本体和控制力矩陀螺在姿态控制任务中复杂的动量传输特性和规律；其次，针对空间飞行器复杂构型，建立基于微元划分的气动力/力矩计算分析方法；之后，在上述基础上基于伴随系统理论求解大型航天器力矩平衡姿态，并对航天器动力学模型在力矩平衡姿态点线性化；最后，基于凸组合控制理论解决存在姿态角和姿态角速度约束条件下的环境力矩动量卸载问题。. 本项目的研究工作对于扩展控制力矩陀螺的应用能力、降低空间飞行器工质消耗、提升在轨寿命具有显著价值，对我国未来大型空间站的在轨建设和运营维护具有重要意义。

针对空间飞行器长期在轨过程中控制力矩陀螺动量饱和问题，本项目重点开展了基于重力梯度力矩和低轨气动力矩的空间飞行器动量卸载技术研究。建立了空间飞行器环境力矩动量卸载模型；完成气动参数与质量参数在轨辨识问题研究，建立复杂构型空间飞行器气动特性分析方法，完成强非线性半解析参数力矩平衡方程求解方法研究；完成了基于凸组合饱和控制理论的姿态指令设计方法研究，同时以某空天飞行器为背景，开展了初步设计及仿真应用尝试。.