【作者】 雷涛；

【导师】 李顺利；

【作者基本信息】 哈尔滨工业大学 ， 飞行器设计， 2009， 硕士

【摘要】 随着空间技术的发展和成熟,外层空间的军事价值越来越明显,为保持空间优势,必然产生空间对抗。在此背景下,除了具备“进入空间”与“利用空间”的能力之外,还必须具备强有力的“控制空间”能力,才能保证空间资源不受侵犯。而轨道机动技术与先进的轨道优化设计方法是完成各种空间对抗任务的基本保障之一。因此,有必要对先进的轨道优化设计方法进行研究。本文以近些年来美国空间对抗系统试验为背景,对有限推力作用下的航天器的轨道优化设计方法与应用进行了研究,主要的研究内容包括以下三个方面:为了避免求解过程中的奇异,建立了改进春分点坐标形式的航天器轨道动力学方程;对地球引力线性化,建立了编队飞行相对动力学方程;利用庞特里亚金极值原理推导了基于上述两种动力学方程的最优控制模型。本文给出三种求解轨道优化设计问题的方法(间接法、混合法和高斯伪谱方法)及求解思路。针对有限推力作用下的轨道优化设计问题,分别用间接法、混合法和高斯伪谱方法求解几类典型的轨迹优化问题。考虑到间接法收敛的困难性,先采用高斯伪谱方法求解,之后再将高斯伪谱方法得到协状态值代入间接法,以此加快间接法计算速度并改善其收敛性。利用混合法和高斯伪谱方法成功求解了轨道提升、大倾角改变、轨道根数大范围改变以及低轨道向GPS卫星轨道转移的轨道优化问题,仿真结果表明高斯伪谱方法对求解复杂轨道优化问题具有较强的适应能力。根据相对动力学原理,针对圆轨道下编队飞行,分析和设计几种特殊的编队队形,获得了形成圆轨道下编队飞行所必须具备的初始条件。然后,利用高斯方法给出了一个空间圆编队飞行的轨道设计方法。更多还原

【Abstract】 With the development and mature of space technology, the martial value of outer space is becoming more and more evident. In order to keep space superiority, space competition is inevitable. In the space competition background, only the ability of entering space and the ability of utilizing space are not enough. What is more important is the power of control space to protect space resources from invasion and to maintain space superiority. Advanced orbit maneuver technique is one of the most important guarantees to complete space competition missions and keep space superiority. It is necessary to study the advanced trajectory optimization techniques and methods.Under USA’s space competition system demonstration test background, the methods and application of orbit optimization design were studied aiming at spacecraft with finite thrust. The work mainly contained the following three parts:In order to avoid the singular phenomenon on the solution process, spacecraft orbit kinetics equations of Modified Equinoctial Elements was derived. The relative kinetics equations for formation flying was establishhed with the linear earth gravitation model. According to pontryagin minimum principle, the optimum control model was founded based on above two kinetics equations. Three kinds of trajectory optimization methods including Indirect method, Hybrid method and Gauss pseudospectral method, as well as solving thoughts were given in this paper.Some typical trajectory optimization problems aiming at finite thrust effect by using Indirect method, Hybrid method and Gauss pseudospectral method respectively. Because it was difficult to enable Indirect Method to converge, Gauss pseudospectral method was used to get costates and then those costates were substituted in the Indirect method to speed up calculation and improve convergence. Hybrid method and Gauss pseudospectral method were used to solve following problems: orbit raising from LEO to GEO, large inclination change from LEO to SSO, orbital elements large-scale change from MEO to Molniya orbit, orbit maneuver from LEO to GPS orbit. It was indicated that Gauss Pseudospetral method had more adaptive to deal with complicated trajectory optimization problem. According to relative kinetics theory, some special formations were analyzed and designed for the formation flying in the case of circular orbit and then obtain initial conditions of circle formation flying. Finally, applying Gauss pseudospectral method give an example of orbit design for circular formation flying.更多还原