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1.
The paper is concerned with control of multidimensional nonstationary processes regarded as adaptive systems of coordinate-parametric control  相似文献   

2.
Theoretical and experimental aspects of design of service devices and systems using burning and explosion energy to separate automatic spacecraft constructions are considered. The main dependences necessary for their calculation are presented. The areas of rational application of one or another type of separation devices are determined, and the results of ground tests of separation systems are given. The practical recommendations on designing the described systems for separation of high-precision automatic spacecraft for planetary and astrophysical investigations are presented.  相似文献   

3.
An approach to the synthesis of an integrated navigation system is considered for a reusable space-craft that performs an arbitrary spatial maneuver under the conditions of internal and external disturbances. The offered approach provides for a noise-suppressing solution of the navigation problem, both in a regular mode of spacecraft motion, and during its descent along the unplanned trajectory.  相似文献   

4.
航天器三维协同研制标准体系研究   总被引:1,自引:0,他引:1  
三维协同研制具有可视化、精确性的特点,是数字化研制的一项重要工作,数字化技术应用标准化是三维协同研制模式推行的基本保证。通过分析产品数字化研制标准体系的现状,基于航天器三维协同数字化研制全流程,构建航天器三维协同研制的数字化标准框架和标准体系,逐条梳理标准体系下的标准细目。文章介绍三维协同数字化标准现状,提出航天器三维协同标准体系框架、体系及其标准组成。  相似文献   

5.
6.
Determination of relative distances and orientations, as well as motion identification is essential in rendezvous and docking and formation flying tasks. A 3D-image generated by a PMD (photonic mixer device) camera, which employs a phase shift measurement of emitted modulated light to derive distance and color information on each pixel, provides in this contribution the basis for near range motion detection and prediction. A novel algorithm based on rotation- and scale-invariant features commonly used for scan matching in high-resolution images is presented. The performance of the PMD camera and of the proposed data processing is characterized in scenarios, considering factors like relative velocities, rotation dynamics, illumination and optical properties of target surface materials, which are major effects for disturbances in this context.  相似文献   

7.
国外高超音速飞行器现状及有关工艺技术研究   总被引:3,自引:0,他引:3  
可重复使用航天发射器和高超音速飞行器技术的开发是美国等西方国家新一代导弹武器、新型航天运载器研究开发的重点.介绍了美国高超音速导弹与再入飞行器的开发情况,叙述了高超音速飞行器试验机X-43A的制造过程,分析了高超音速飞行器热结构工艺.  相似文献   

8.
Xi Liu  K.D. Kumar 《Acta Astronautica》2011,68(11-12):1847-1859
This paper investigates the formation keeping problem for multiple spacecraft in the framework of networked control systems (NCSs). A continuous-time representation of the NCS is considered for the tracking control of relative translational motion between two spacecraft in a leader–follower formation in the presence of communication constraints and system uncertainties. Model-based control schemes are presented, which employ state feedback (when the relative position and velocity vectors are directly measurable) and output feedback (when velocity measurements are not available), respectively, to guarantee input-to-state stability (ISS) of the system. The stability conditions on network transfer intervals are derived as simple eigenvalue tests of a well-structured test matrix. The results are then extended to include network communication delay. Numerical simulations are presented to demonstrate the effectiveness of the control scheme ensuring high formation keeping precision and robustness to nonlinearities and system uncertainties. The proposed controllers are robust not only to structured uncertainties such as system parameter perturbations but also to unstructured uncertainties such as external disturbances and measurement noises.  相似文献   

9.
关于导弹武器系统作战效能评估问题的探讨   总被引:25,自引:3,他引:25  
通过论述导弹武器系统作战效能的基本要领和基本评估方法,探讨了效能评估方法论意义,从而提出军事系统效能评估的软算法的思想方法,并从方法论的角度提出效能评估软度量的几个基本技术,文章的结构由以下五部分组成,首先是引言,概述了效能评估的重要性与必要性;其次,介绍了效能评估的基本概念;接着,述评了效能评估的九种方法,然后,论述了效能评估的方法论和软度量方法,最后,研究了软技术在效能评估中的应用,特别是效能评估辅助决策支持系统在多枚导弹协同攻击中的应用研究。利用人机交互的思想,给出了系统的概念框架。  相似文献   

10.
航天器故障诊断与容错控制技术综述   总被引:13,自引:5,他引:13  
对容错技术和故障诊断技术的发展过程进行了简要综述,并在分析航天器故障诊断与容错控制特点的基础上,介绍了当前国际上航天器故障诊断及容错控制的发展现状,并分析了我国在这方面的研究现状与差距,最后对航天器故障诊断与容错控制方面有待解决的问题及发展方向发表了一些作者的看法。  相似文献   

11.
A design procedure is presented for an attitude control system consisting of a momentum wheel and a reaction wheel. Control laws are designed for this system using modern control techniques. The observer based method produces a control scheme which achieves a good transient response.  相似文献   

12.
返回舱弹道重建与黑障区弹道再现研究   总被引:2,自引:1,他引:2  
汪清  和争春  方方  万宗国 《宇航学报》2004,25(6):595-599,615
对于飞船返回舱,黑障区弹道再现是再人飞行试验气动分析工作的重要环节。利用舱上测量数据和有限的雷达测量数据重构飞行弹道,是黑障区弹道再现的有效方法。本文建立了返回舱弹道重建的数学模型,包括运动学模型、观测模型、测量误差模型,从而将返回舱弹道重建问题转化为一个非线性动态系统的参数辨识问题。给出了基于极大似然判据和Newton-Raphson迭代的弹道重建算法。对某飞船返回舱的飞行试验数据进行了计算和分析,结果证实了弹道重建数学模型的正确性和算法的可行性。通过弹道重建,不仅再现了黑障区的弹道,而且提供了可靠的、完整的弹道数据。  相似文献   

13.
An approach to the synthesis of autonomous navigation support is considered for a spacecraft executing an arbitrary spatial maneuver under conditions of internal and external disturbances. The proposed approach ensures the solution to the problem of a joint estimation of the state vector of a navigation system and the identification of the parameters of sensitive elements. A complex observer ensuring the autonomous estimation of the parameters of angular and linear motions is used to improve the accuracy of the estimation of the parameters of angular and linear motions.  相似文献   

14.
航天器质量特性测试技术新进展   总被引:2,自引:2,他引:2  
航天器质量特性测试提供航天器轨道控制和姿态控制所需的质量特性参数,同时验证航天器结构和布局设计的合理性,为持续改进提供依据,在航天器的研制中占有重要地位.文章在对国内和欧美等航天发达国家航天器质量特性测试技术深入调研的基础上,阐述了国内外航天器质量特性技术的进展情况,重点分析了NASA哥达德空间飞行中心和欧空局下属法国...  相似文献   

15.
In order to carry out tasks of the RadioAstron mission, a high-apogee orbit was designed. On average, the period of its satellite’s orbit around the Earth is 8.5 days with evolution due to gravitational perturbations produced by the Moon and the Sun. The perigee and apogee of this orbit vary within the limits 7500–70000 km and 270000–333000 km, respectively. The basic evolution of the orbit represents a rotation of its plane around the line of apsides. Over 3 years, the plane normal to the orbit draws on the celestial sphere an oval with a semi-major axis of about 150° and semi-minor axis of about 45°.  相似文献   

16.
Space vehicles are often characterized by highly flexible appendages, with low natural frequencies which can generate coupling phenomena during orbital maneuvering. The stability and delay margins of the controlled system are deeply affected by the presence of bodies with different elastic properties, assembled to form a complex multibody system. As a consequence, unstable behavior can arise. In this paper the problem is first faced from a numerical point of view, developing accurate multibody mathematical models, as well as relevant navigation and control algorithms. One of the main causes of instability is identified with the unavoidable presence of time delays in the GNC loop. A strategy to compensate for these delays is elaborated and tested using the simulation tool, and finally validated by means of a free floating platform, replicating the flexible spacecraft attitude dynamics (single axis rotation). The platform is equipped with thrusters commanded according to the on–off modulation of the Linear Quadratic Regulator (LQR) control law. The LQR is based on the estimate of the full state vector, i.e. including both rigid – attitude – and elastic variables, that is possible thanks to the on line measurement of the flexible displacements, realized by processing the images acquired by a dedicated camera. The accurate mathematical model of the system and the rigid and elastic measurements enable a prediction of the state, so that the control is evaluated taking the predicted state relevant to a delayed time into account. Both the simulations and the experimental campaign demonstrate that by compensating in this way the time delay, the instability is eliminated, and the maneuver is performed accurately.  相似文献   

17.
《Acta Astronautica》2014,93(2):495-510
Feasibility of achieving reliable control for spacecraft formation keeping and reconfiguration without the need for thrust in either the radial or along-track direction is explored in this paper. Analysis of the linearized dynamics without along-track input indicates the presence of an uncontrollable eigenvalue at the origin. A nonlinear controller is designed to indirectly stabilize the uncontrollable modes to a stable manifold around the equilibrium. Conditions for robustness against unmatched uncertainties and disturbances are derived to establish the regions of asymptotic stabilization. The benefits of the proposed control method are also validated via numerical simulations to show that precise formation maintenance can be achieved by dealing with the issues of system nonlinearities, variations in initial conditions, and external disturbances, concurrently.  相似文献   

18.
The problem of a rendezvous of two spacecraft in close near-circular noncoplanar orbits is considered. The angles of applying velocity impulses and their orientation are determined from necessary conditions of optimality derived using the basis vector theory. For non-degenerate six-impulse solutions the analytical formulas are found that approximate the dependence of moments of applying velocity impulses and angles determining their orientation on the rendezvous duration. The total characteristic velocity of six-impulse solutions (or five-impulse solutions derived from them) is compared to the total characteristic velocity obtained when solving the Lambert problem.  相似文献   

19.
This paper proposes a framework for the integrated development of space products. The framework is called ‘total view framework’ because it provides the total set of product, process and organisation elements and their interactions from the outset in the development process. It uses systems engineering (SE) and concurrent engineering (CE) in an integrated manner, as part of the same framework. The framework extends the application of the SE process to life cycle processes and their performing organisations and applies CE at all levels of the hierarchical product breakdown structure. The ‘total view framework’ is supported by a method, called ‘concurrent structured analysis method’, that consists of the three analysis processes: requirements, functional and physical. These processes mirror the bulk of the SE process and are applied concurrently to product, process and organisations. The outputs of the method are requirements, functional attributes, physical attributes and the interactions among them. These outputs are then analysed using a clustering algorithm and a complexity metric based on cohesion and coupling shows the clustering effects.  相似文献   

20.
上海航天技术研究院在神舟飞船研制中取得的科研成果   总被引:1,自引:0,他引:1  
施金苗  罗斌 《宇航学报》2004,25(4):462-465
通过神舟飞船的研制,上海航天技术研究院在飞船电源分系统、推进分系统、测控与通信分系统、推进舱等关键系统和产品的研制工作中探索并总结出了国内领先的专业技术成果,确保了神舟飞船研制目标实现。  相似文献   

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