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Francesco Topputo Edward Belbruno Marian Gidea 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,42(8):1318-1329
A special set of solutions governing the motion of a particle, subject to the gravitational attractions of the Earth, the Moon, and, eventually, the Sun, is discussed in this paper. These solutions, called resonant orbits, correspond to a special motion where the particle is in resonance with the Moon. For a restricted set of initial conditions the particle performs a resonance transition in the vicinity of the Moon. In this paper, the nature of the resonance transition is investigated under the perspective of the dynamical system theory and the energy approach. In particular, using a new definition of weak stability boundary, we show that the resonance transition mechanism is strictly related to the concept of weak capture. This is shown through a carefully computed set of Poincaré surfaces, at different energy levels, on which both the weak stability boundary and the resonant orbits are represented. It is numerically demonstrated that resonance transitioning orbits pass through the weak stability boundaries. In the second part of the paper the solar perturbation is taken into account, and the motion of the resonant orbits is studied within a four-body dynamics. We show that, for a wide class of initial conditions, the particle escapes from the Earth–Moon system and targets an heliocentric orbit. This is a free ejection called a ballistic escape. Astrodynamical applications are discussed. 相似文献
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S.P. Sosnitskii 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
In the three-body problem, we consider the Lagrange and Hill stability including the Lagrange stability for the manifold of symmetric motions that exists in the case where two of three bodies have equal masses. To analyze the stability, in addition to integrals of energy and angular momentum we use the Lagrange–Jacobi equality. We prove theorems on the Lagrange and Hill stability. The theorem on the Hill stability has effective application in the case where the mass of a body is much less than masses of two other bodies. In this case, as it is known, the model of the restricted three-body problem is usually applied. 相似文献
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Long term dynamics and optimal control of nano-satellite deorbit using a short electrodynamic tether 总被引:1,自引:0,他引:1
R. Zhong Z.H. Zhu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
This paper studies the long term dynamics and optimal control of a nano-satellite deorbit by a short electrodynamic tether. The long term deorbit process is discretized into intervals and within each interval a two-phase optimal control law is proposed to achieve libration stability and fast deorbit simultaneously. The first-phase formulates an open-loop fast-deorbit control trajectory by a simplified model that assumes the slow-varying orbital elements of electrodynamic tethered system as constant and ignores perturbation forces other than the electrodynamic force. The second phase tracks the optimal trajectory derived in the first phase by a finite receding horizon control method while considering a full dynamic model of electrodynamic tether system. Both optimal control problems are solved by direct collocation method base on the Hermite–Simpson discretization schemes with coincident nodes. The resulting piecewise nonlinear programing problems in the sequential intervals reduces the problem size and improve the computational efficiency, which enable an on-orbit control application. Numerical results for deorbit control of a short electrodynamic tethered nano-satellite system in both equatorial and highly inclined orbits demonstrate the efficiency of the proposed control method. An optimal balance between the libration stability and a fast deorbit of satellite with minimum control efforts is achieved. 相似文献
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针对低温液体火箭发动机涡轮泵转子非线性系统开展了轴承位置对稳定性的影响研究。建立了涡轮泵转子非线性系统的动力学模型,分别研究了理想安装时和非理想安装条件下泵端和涡轮端轴承位置变化对转子系统稳定性的影响,给出了失稳转速随轴向位置的变化规律,为液体火箭发动机涡轮泵转子系统结构设计、故障诊断与安装维护提供理论依据。 相似文献
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飞翼布局无人机的稳定与操纵特性分析研究 总被引:2,自引:0,他引:2
从气动和控制综合设计角度,提出了解决飞翼布局无人机稳定能力问题的多轴静不稳定增稳控制规律,通过对多操纵面操纵特性和操纵需求分析给出了操纵面的配置策略.仿真分析表明,所提出的设计方法较好地解决了飞翼布局无人机特殊的稳定与操纵问题. 相似文献
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