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Neuro-Optimal Guidance Control for Lunar Soft Landing

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Journal of Systems Engineering and Electronics 1999年第3期10卷 22-31页

作者： Wang, Dayi Li, Tieshou Yan, Hui ma, xingrui Harbin Inst of Technology Harbin China

Returning to moon has become a top topic recently. many studies have shown that soft landing is a challenging problem in lunar exploration. The lunar soft landing in this paper begins from a 100 km circular lunar parking orbit. Once the landing area has been selected and it is time to deorbit for landing, a ΔV burn of 19.4 m/s is performed to establish a 100×15 km elliptical orbit. At perilune, the landing jets are ignited, and a propulsive landing is performed. A guidance and control scheme for lunar soft landing is proposed in the paper, which combines optimal theory with nonlinear neuro-control. Basically, an optimal nonlinear control law based on artificial neural network is presented, on the basis of the optimum trajectory from perilune to lunar surface in terms of Pontryagin's maximum principle according to the terminal boundary conditions and performance index. Therefore some optimal control laws can be carried out in the soft landing system due to the nonlinear mapping function of the neural network. The feasibility and validity of the control laws are verified in a simulation experiment.

关键词： Boundary conditions Computer simulation Control system analysis Control system synthesis Functions Lunar landing Lunar missions maximum principle Neural networks Nonlinear control systems Optimal control systems Orbits

Developing Space manufacturing Industry To Serve National Economy And Promote Social Progress

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Aerospace China 2008年第2期9卷 2-7页

作者： ma xingrui President of China Aerospace Science and Technology Corporation (CASC)

Over the past 50 or more years, China's space industry has made brilliant achievements typically represented by the three milestones in China's space development history,*** the first man-made satellite into space in 1970,realizing the manned spaceflight for the first time in 2003 and sending the first lunar probe to the moon in *** the same time, China's space industry has also mastered a great number of core technologies based upon its own intellectual property rights,accumulated rich experiences

关键词：中国航天工业发展史人造卫星

Development and market Prospect of China's Space Technology and Industry

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Aerospace China 2004年第4期 4-8页

作者： ma xingrui, Vice President of CASC

On Oct. 31, 2004, China Aviation & Aerospace Summit Forum held in Zhuhai, Vice President of CASC, Mr. ma xingrui addressed the forum. The context of the article is as ***’s space program has gone through a history of 48 years and has made world-famous achievements under the great support of the Central Government. The program has been carried out based on relatively poor industrial and technical conditions and under special national and historic circumstances. It has gone through a way unique to China with less investment. As an important part of the program, space technology

关键词： In CASC Development and market Prospect of China’s Space Technology and Industry

INVESTIGATION ON THE SCATTERINGOF ELASTIC WAVES (P OR SV) BY A PLANEINTERFACE CRACK IN LAYERED MEDIA

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Chinese Journal of Aeronautics 1990年第2期5卷 98-106页

作者： ma xingrui, Zou Zhenzhu, Shao Chengxun and Huang WenhuHarbin Institute of Technology, P.R.China

In this paper, the scattering of elastic waves by a plane interface crack in Layered media is investigated. By Fourier integral transform, the method of transfer matrix is extended to the scattering of elastic waves by a plane interface crack in layered media, and the problems are reduced to a set of dual integral equations in matrix form. As an example, the far field modes of scattering of elastic waves by a plane interface crack in a layered half space have been presented. Amplitudes in far field modes are plotted versus incident wave frequency for several groups of different material combinations, and the numerical results show that resonance peaks occur at some frequencies. The frequencies at which the resonanse peaks occur for P and SV waves are almost the same.

关键词： P OR SV BY A PLANEINTERFACE CRACK IN LAYERED MEDIA INVESTIGATION ON THE SCATTERINGOF ELASTIC WAVES

DYNAMIC STRESS CONCENTRATIONS IN AMBARTSUMIAN'S PLATE WITH A CUTOUT

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Acta Mechanica Solida Sinica 1998年第4期11卷 341-350页

作者： Hu Chao Zhao Xinghua (Institute of Applied mathematics and Mechanics,Shanghai University,Shanghai 200072,China)ma xingrui Huang Wenhu (Harbin Institute of Technology,Harbin 150001,China) Shanghai Univ Inst Appl Math & Mech Shanghai 200072 Peoples R China Harbin Inst Technol Harbin 150001 Peoples R China

Based on the motion equations of flexural wave in Ambartsumian' s plates including the effects of transverse shear deformations,by using perturbation method of small parameter,the scatter- ing of flexural waves and dynamic stress concentrations in the plate with a cutout have been studied. The asypmtotic solution of the dynamic stress problem is *** results for the dynamic stress concentration factor in Ambartsumian's plates with a circular cutout are graphically presented and discussed.

关键词： Ambartsumian's plate cutout dynamic stress concentration perturbation method

基于非线性模态的航天器铰接结构基频特性研究

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中国空间科学技术 2005年第3期25卷 19-27页

作者：王巍于登云马兴瑞中国空间技术研究院北京100086 中国航天科技集团北京100830

将航天器铰接结构简化为具有局部铰链非线性约束的多自由度系统,提出了对该类非线性系统动力学特性进行分析的方法。即首先通过拟合模态方法建立铰接结构系统的非线性动力学模型,然后通过数值方法得到系统的非线性模态,并以之为基础对... 详细信息

将航天器铰接结构简化为具有局部铰链非线性约束的多自由度系统,提出了对该类非线性系统动力学特性进行分析的方法。即首先通过拟合模态方法建立铰接结构系统的非线性动力学模型,然后通过数值方法得到系统的非线性模态,并以之为基础对铰接结构的基频特性进行研究。

关键词：铰链间隙非线性模态分析航天器非线性模态铰接结构特性研究基频非线性动力学模型

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航天器振动试验力限条件设计半经验方法

中国空间科学技术 2011年第1期31卷 1-7页

作者：李正举马兴瑞韩增尧中国空间技术研究院北京100094 中国航天科技集团公司北京100037

力限振动试验可以缓解传统加速度控制振动试验在试验件共振频率处产生的振动"过试验"现象。计算力限条件是进行力限振动试验的前提。介绍了力限振动试验的基本原理,给出了计算力限条件的基本过程,采用二自由度系统模型详细推导了半经验... 详细信息

力限振动试验可以缓解传统加速度控制振动试验在试验件共振频率处产生的振动"过试验"现象。计算力限条件是进行力限振动试验的前提。介绍了力限振动试验的基本原理,给出了计算力限条件的基本过程,采用二自由度系统模型详细推导了半经验系数的计算方法,基于此方法计算了某航天器有效载荷力限随机振动试验的力限条件。结果显示,该方法可合理确定力限振动试验的力限条件。

关键词：振动试验力限条件半经验方法二自由度系统航天器

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结构动力学模型修正的三步策略及其实践

航空学报 2010年第3期31卷 546-552页

作者：丁继锋马兴瑞韩增尧庞世伟北京空间飞行器总体设计部北京100094 中国航天科技集团公司北京100037

首先构建了由模型结构调整、模型参数修正以及模型确认组成的三步模型修正策略。该方法优于传统模型修正方法的是:在模型修正之初基于误差定位、灵敏度分析以及工程经验进行的模型结构调整可以给出一个适于参数修正的初始有限元模型,从... 详细信息

首先构建了由模型结构调整、模型参数修正以及模型确认组成的三步模型修正策略。该方法优于传统模型修正方法的是:在模型修正之初基于误差定位、灵敏度分析以及工程经验进行的模型结构调整可以给出一个适于参数修正的初始有限元模型,从而保证了模型修正的成功。然后,采用三步法针对国际上模型修正的标准考题——GARTEUR19结构动力学模型进行修正,详尽论述了模型结构调整、参数修正以及模型确认的过程,并将修正结果与国外同行的研究结果进行了对比,综合精度与国际先进水平相当,从而验证了三步模型修正策略的有效性。

关键词：三步策略模型结构调整参数修正模型确认灵敏度分析 GARTEUR19模型

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不确定载荷下的桁架结构拓扑优化

北京航空航天大学学报 2009年第10期35卷 1170-1173,1178页

作者：李东泽于登云马兴瑞北京空间飞行器总体设计部北京100094 中国空间技术研究院北京100094 中国航天科技集团公司北京100037

对带有不确定扰动载荷的桁架结构拓扑优化问题进行了研究.将不确定载荷表示成有界凸集,从而把不确定性问题转化为一个确定性问题.构造了凸集载荷下以体积为约束的柔度最小化模型,该优化模型的实质是在高维椭球内计算最大柔度最小问题.... 详细信息

对带有不确定扰动载荷的桁架结构拓扑优化问题进行了研究.将不确定载荷表示成有界凸集,从而把不确定性问题转化为一个确定性问题.构造了凸集载荷下以体积为约束的柔度最小化模型,该优化模型的实质是在高维椭球内计算最大柔度最小问题.由于采用传统优化模型存在计算上的困难,对凸集载荷进行了数学处理,并据此构造了半定规划形式的优化模型以便求解.优化结果相对于给定载荷的刚度虽然略低,但对不确定的扰动载荷却具有一定的承载能力.算例表明通过半定规划法构造的考虑扰动载荷作用下的优化结果鲁棒性较佳,结构形式更接近于实际工程结构.

关键词：桁架拓扑优化不确定载荷鲁棒