共查询到20条相似文献,搜索用时 125 毫秒
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针对地球同步轨道绳系太阳能电站在轨运行的动力学问题,建立复杂绳系编队系统的动力学模型。此模型考虑了系绳的柔性、太阳能子板的姿态运动、编队系统构型与轨道运动之间相互耦合的特性。在无扰动及存在初始太阳能子板姿态误差的情况下对系统进行动力学仿真,分析了系统的稳定性。结果表明:不同方向上的初始太阳能子板姿态误差对系统的影响不同,指向地心方向上的初始姿态误差不会引起系统的运动,另外两方向上初始姿态误差会引起柔性系绳内力变化从而对系统产生影响,其中轨道运行方向上的初始姿态误差对系统的影响最明显;较小的初始姿态误差所引起的系统运动主要为太阳能子板在其平衡位置附近的小幅往复转动;初始姿态误差较大时,平台系统会大幅偏离其平衡位置,影响空间绳系太阳能电站的构型保持。 相似文献
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利用地面物理仿真平台研究了绳系航天器的混沌动力学行为. 首先, 根据天地动力学相似原理, 通过对卫星仿真器施加喷气力和动量轮力矩来模拟空间动力学环境, 提出了两种等效方案, 给出了它们各自适用的实验工况. 数值结果表明, 在轨绳系航天器在一定的参数条件下系绳摆动为周期或概周期运动、航天器姿态发生混沌运动. 物理仿真验证了等效方案的有效性, 揭示了绳系航天器的混沌运动特征, 表明在阻尼力矩的作用下可以避免绳系航天器混沌运动的发生. 相似文献
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双小行星系统由在万有引力作用下彼此环绕的两颗小行星组成, 对研究太阳系起源、行星系统演化和行星防御都具有重要的价值, 近年来成为行星科学和航天动力学研究的热门对象, 对双小行星系统的原位探测也即将迎来热潮. 双小行星系统的独特构型和附近的复杂动力学环境为探测器轨道动力学和任务设计带来了全新的挑战, 为应对这些挑战所进行的研究也推动了轨道动力学基础理论的发展. 本文对双小行星探测轨道动力学的研究进展进行综述, 首先介绍了双小行星研究和探测的背景及意义, 简要阐述了双小行星系统形成理论及其附近轨道动力学的研究概况. 其次, 介绍了双小行星系统不规则引力场和相互引力势的建模方法, 进而展示了双星的姿态轨道耦合动力学, 即完全二体问题, 包括双星相对运动的平衡构型和稳定性. 接着, 介绍了描述双星附近探测器轨道运动的限制性完全三体问题的动力学模型, 以及该模型下的平动点、平动点周期轨道、大范围周期轨道、转移轨道和轨道维持等方面的研究进展. 第四部分综述了环绕双小行星系统单颗星的受摄二体问题, 以轨道摄动理论和行星系统中受摄二体问题的研究现状为背景, 介绍了环绕双小行星系统主星的半解析轨道动力学建模与轨道稳定性分析. 之后, 介绍了目前面向探测任务需求和考虑实际约束的轨道动力学研究和轨道设计. 最后, 基于目前研究进展, 分析了面临的若干问题, 对未来双小行星探测轨道动力学及相关技术的发展进行了讨论和展望. 相似文献
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Libration suppression of tethered space system with a moving climber in circular orbit 总被引:1,自引:0,他引:1
This paper studies the dynamics and libration suppression of a tethered system with a moving climber in circular orbits. The tethered system is modeled by a two-piece dumbbell model that consists of one main satellite, one climber and one end-body connected by two straight, massless and inextensible tethers. A new tension control strategy to suppress the libration of the tethered system due to the moving climber is proposed by reeling in-out tether at the end-body without thrust. The control strategy is implemented with the sliding mode control to suppress the libration angle of the climber to zero by the end of climber’s transfer phase. The numerical results show that the proposed control strategy is very effective in suppressing the libration of the climber in the three-body tethered system with tension control only. Furthermore, cases with limited tension control are examined. It reveals that a longer tether between the climber and the end-body is required to supplement the limited tension in suppressing the libration of the climber. 相似文献
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A new control law based on characteristic exponent assignment for libration point orbit maintenance 下载免费PDF全文
Jian Wei·Shi-Jie Xu Laboratory School of Astronautics Beihang University Beijing China 《Acta Mechanica Sinica》2010,26(3):495-500
A new method is developed for stabilizing motion on collinear libration point orbits using the formalism of the circular restricted three body problem. Linearization about the collinear libration point orbits yields an unstable linear parameter-varying system with periodic coefficients. Given the variational equations, an innovative control law based on characteristic exponent assignment is introduced for libration point orbit maintenance. A numerical simulation choosing the Richardson's third order approximation for a halo orbit as a nominal orbit is conducted, and the results demonstrate the effectiveness of this control law. 相似文献
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Spacecrafts in periodic or quasi-periodic orbits near the collinear libration points are proved to be excellent platforms for scientific investigations of various phenomena. Since such periodic or quasi-periodic orbits are exponentially unstable, the station-keeping maneuver is needed. A station-keeping strategy which is found by an analytical method is presented to eradicate the dominant unstable component of the libration point trajectories. The inhibit force transforms the unstable component to a stable component. In this method, it is not necessary to determine a nominal orbit as a reference path. 相似文献
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平动点是圆型限制性三体问题中的五个平衡解.其中,三角平动点在平面问题中具有“中心×中心”的动力学特性,其附近存在着大量的周期轨道,研究这些周期轨道的构建方法在深空探测中具有理论及工程意义.本文从振动角度分析周期轨道,通过多项式展开法构建出主坐标下周期轨道两个运动方向之间的渐近关系.从新的角度分析了系统的动力学特性和平面周期运动两个方向内在关联以及物理规律.这种多项式形式的关系式,可以作为约束条件用于数值微分修正算法中,通过迭代的方式寻找周期轨道.数值仿真算例验证了方法的正确性及精确性.文章从振动的角度对周期轨道进行分析,改进了微分修正算法.提出的方法可以被拓展至圆型/椭圆型限制性三体问题的三维周期轨道构建中. 相似文献
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Periodicity of motion around the collinear libration point associated with the Elliptic Restricted Three-Body Problem is studied. A survey of periodic solutions in the Circular Restricted Three-Body Problem is presented considering both Sun–Earth and Earth–Moon systems. Halo, Lyapunov and Vertical families around L1, L2 and L3 points are investigated, and their orbital period ranges through the entire family are reported. Resonant motions within the orbit families in the circular problem are identified and selected as suitable initial guess to find periodic orbits in the elliptic problem, which are targeted using a differential correction algorithm. Periodic solutions found are cataloged depending on the number of revolutions around libration points. Geometry, dynamical behavior and stability properties of single-revolution orbits are shown, as well as double-, triple- and quadruple-revolution solutions. 相似文献
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研究了圆型限制性三体问题的平动点在连续小推力作用下的具体位置和动力学特征的变化. 研究表明,随着小推力方向在空间中的变化,平动点的具体位置也会发生相应的变化,文章详细阐述了这些变化的特征.针对航天任务中应用较多的共线平动点L1和L2,研究了其附近运动的稳定性状态,给出了线性条件稳定解,并在此基础上,构造了条件稳定解的高阶形式,将其结果与数值积分轨道进行了比对,两者符合得很好. 最后,进一步研究了共线平动点附近周期轨道族的演化状态,由于连续小推力引入的非对称性,周期轨道族会发生分岔现象. 相似文献
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This paper presents a dynamic analysis of a tethered satellite system with a moving mass. A dynamic model with four degrees of freedom, i.e., a two-piece dumbbell model, is established for tethered satellites conveying a mass between them along the tether length. This model includes two satellites and a moving mass, treated as particles in a single orbital plane, which are connected by massless, straight tethers. The equations of motion are derived by using Lagrange’s equations. From the equations of motion, the dynamic response of the system when the moving mass travels along the tether connecting the two satellites is computed and analyzed. We investigate the global tendencies of the libration angle difference (between the two sections of tether) with respect to the changes in the system parameters, such as the initial libration angle, size (i.e. mass) of the moving mass, velocity of the moving mass, and tether length. We also present an elliptic orbit case and show that the libration angles and their difference increase as orbital eccentricity increases. Finally, our results show that a one-piece dumbbell model is qualitatively valid for studying the system under certain conditions, such as when the initial libration angles, moving mass velocity, and moving mass size are small, the tether length is large, and the mass ratio of the two satellites is large. 相似文献
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平动点附近周期轨道的不变流形因其在低能轨道转移中起着重要作用而受到广泛关注.在设计低能轨道过程中不变流形要实时进行能量匹配,但利用传统数值积分方法进行积分时能量会耗散.显式辛算法具有比隐式辛算法计算效率高的优势,但其要求Hamilton系统必须分成两个可积的部分,而旋转坐标系下的圆型限制性三体问题是不可分的,因而显式辛算法难以用于求解旋转坐标系下的圆型限制性三体问题.本文通过引入混合Lie算子,成功实现了带三阶导数项的力梯度辛算法对圆型限制性三体问题的求解,并将基于混合Lie算子的带三阶导数项的辛算法与Runge-Kutta78算法和Runge-Kutta45算法进行仿真对比,仿真结果表明基于混合Lie算子的含有三阶导数项的辛算法位置精度高、能量误差小且计算效率高.利用基于混合Lie算子的带三阶导数项的辛算法计算不变流形,可以实现低能轨道转移过程中轨道拼接点的能量精准匹配. 相似文献
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Equilibrium points, primary and secondary static bifurcation branches, and periodic orbits with their bifurcations of discrete systems under partial follower forces and no initial imperfections are examined. Equilibrium points are computed by solving sets of simultaneous, non-linear algebraic equations, whilst periodic orbits are determined numerically by solving 2- or 4-dimensional non-linear boundary value problems. A specific application is given with Ziegler's 2-DOF cantilever model. Numerous, complicated static bifurcation paths are computed as well as complicated series of periodic orbit bifurcations of relatively large periods. Numerical simulations indicate that chaotic-like transient motions of the system may appear when a forcing parameter increases above the divergence state. At these forcing parameter values, there co-exist numerous branches of bifurcating periodic orbits of the system; it is conjectured that sensitive dependence on initial conditions due to the large number of co-existing periodic orbits causes the chaotic-like transients observed in the numerical simulations. 相似文献
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In this paper, the bifurcations of subharmonic orbits are investigated for six-dimensional non-autonomous nonlinear systems using the improved subharmonic Melnikov method. The unperturbed system is composed of three independent planar Hamiltonian systems such that the unperturbed system has a family of periodic orbits. The key problem at hand is the determination of the sufficient conditions on some of the periodic orbits for the unperturbed system to generate the subharmonic orbits after the periodic perturbations. Using the periodic transformations and the Poincaré map, an improved subharmonic Melnikov method is presented. Two theorems are obtained and can be used to analyze the subharmonic dynamic responses of six-dimensional non-autonomous nonlinear systems. The subharmonic Melnikov method is directly utilized to investigate the subharmonic orbits of the six-dimensional non-autonomous nonlinear system for a laminated composite piezoelectric rectangular plate. Using the subharmonic Melnikov method, the bifurcation function of the subharmonic orbit is obtained. Numerical simulations are used to verify the analytical predictions. The results of the numerical simulation also indicate the existence of the subharmonic orbits for the laminated composite piezoelectric rectangular plate. 相似文献