基于能量切换的航天器系统动力学建模与控制

In modern flight missions, such as the rocket stage separation, spacecraft rendezvous and docking and vehicle reentry etc., there are problems that rapid quality change, structural mutation and drastic change of flight condition. The forementioned problems often induce that the system parameters vary in a great extent so that the general dynamic modeling and control could not meet the required performance. The energy-based switching modeling and control strategy is an effective scheme to deal with the above issue. Based on the profound research of the energy mechanism of the spacecraft system, the energy-based switching problem in the dynamic modeling and control of the spacecraft is addressed in the project. The dynamic modeling and control method for the switching system is investigated by the mass-energy transfer theory and energy dissipation theory. And then, the modeling, stability analysis and control system design based on the energy-based switching system are proposed. the real-time hardware in the loop simulation system for spacecraft is established, and the software of dynamic modeling and control is compiled to validate the proposed theory, methods and the feasibility for engineering application. This project seeks for a new method for the dynamic modeling and control of the spacecraft, and provides theoretical basis for the design of dynamic modeling and analysis of the spacecraft by the energy-based switching method.

现代航天飞行任务中，如大型运载火箭助推器分离、空间交会对接、飞行器再入等，存在瞬间质量变化、结构突变或飞行条件剧变等问题，导致系统参数大范围变化，常规的系统动力学建模与控制无法满足任务要求，而基于能量切换的建模与控制策略是一种有效的解决途径。本项目拟在深入分析航天器能量作用机理的基础上，凝练与航天器系统动力学建模与控制相关的能量切换问题，研究基于质能交换和能量耗散性的切换系统动力学建模和控制，提出基于能量切换的航天器系统动力学建模框架、稳定性分析判据和控制综合方法，建立航天器半实物实时仿真平台，且编制动力学建模与控制仿真软件，验证所提理论与方法的有效性及工程推广的可行性。本项目力求为航天器系统的动力学建模和控制提供新的思路，为有效利用能量切换方法解决航天器的动力学建模与控制问题奠定良好的理论基础。

本项目基于切换系统理论，研究了航天器的动力学建模、控制系统稳定性分析与控制器综合等问题。. 在航天器动力学建模方面，推导了能量描述的航天器非线性模型，并进一步得到航天器的切换多胞模型、切换LPV模型以及切换多胞LPV模型，所得模型能很好地刻画航天器动力学特性。进一步采用局部重叠切换系统描述航天器，保证了切换过程的平滑性。. 在基于能量的航天器动力学系统稳定性分析方面，首先基于线性切换系统模型，研究了航天器控制系统有限时间有界、符号稳定、全局稳定及指数稳定的条件。采用模态依赖平均驻留时间方法，充分利用各个子系统的特征，降低了保守性。基于自抗扰控制方法，分析了存在执行机构饱和情况下非线性系统模型的稳定性。. 在航天器控制器设计方面，基于切换多胞系统理论、切换LPV系统理论研究了多个类型航天器的抗干扰控制、平滑切换控制、故障检测与容错控制、异步切换控制等问题，使得航天器能够实现姿态的精确跟踪，以及飞行过程中的稳定性。此外，基于自抗扰控制，设计了能够保证系统稳定的抗饱和非线性控制系统，保证系统的稳定性和鲁棒性。