共查询到18条相似文献,搜索用时 203 毫秒
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对自旋弹头实现末端机动的变质心控制系统进行了研究。采用牛顿力学方法重新建立了自旋弹头的姿态运动模型。在此基础上,采用自适应变结构控制方法设计了变质心控制系统,对弹头内部质量块的偏移运动进行控制,进而准确地控制自旋弹头的姿态运动。仿真结果表明:所设计的变质心控制系统具有快速性和较高的控制精度,实现了对自旋弹头姿态角的准确控制。 相似文献
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高速列车通过隧道时无法接收卫星信号,而仅依靠惯性导航的定位误差增长较快,针对这一问题提出了一种利用列车和隧道特点辅助惯性导航的方法。该方法使用GNSS和运动约束估计IMU相对于车体的安装角,并在隧道内使用运动约束和路标跨距约束提高列车的定位精度。基于状态变换卡尔曼滤波设计了系统方程和观测方程,与传统方法相比,系统方程更接近线性定常系统,滤波时间更新方程与测量修正方程可采用相同的计算频率,减小实时计算负担,有利于高速运动下的组合导航。基于实际的高速列车行驶实验,设计了列车穿越隧道的仿真实验,实验结果表明,两种约束辅助的惯性导航在隧道内的定位精度有明显提高,优于3‰行程。 相似文献
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变质心自旋弹头的姿态运动建模与仿真分析 总被引:2,自引:0,他引:2
为了明确直观地表现自旋弹头姿态运动与控制量之间的关系,采用牛顿力学方法建立了自旋弹头的姿态运动模型。选取质量块的运动方式为正弦运动,推导了质量块的运动加速度。为了分析质量块运动对自旋弹头姿态运动的影响,构建了仿真模型,选取质量块的三种不同运动频率进行了对比仿真。仿真结果表明,质量块的运动频率越大,即其运动加速度越大,引起的自旋弹头俯仰角和偏航角的变化范围越大,自旋弹头的机动能力越大。 相似文献
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四元数在伴随卫星姿态控制中的应用 总被引:2,自引:1,他引:1
针对传统的欧拉角方法不适用于航天器大幅度姿态机动运动的数值仿真。研究了用四元 空间站伴随卫星的姿态控制问题。介绍了空间站伴随卫星的概念及任务;根据航天器动力学方程,利用李雅普诺夫直接法推导出用四元数表示的空间站伴随卫星姿态控制律,并对该控制律进行了仿真计算,仿真结果表明,所推导的控制律能对空间站伴随卫星进行准确、快速的姿态控制。 相似文献
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The optimal terminal rendezvous of two satellites in orbit about the Earth is studied using a stochastic model and formulating the rendezvous as a game problem. Each satellite has noise-corrupted output measurements and uses a Kalman filter to generate the best estimate of the states describing the rendezvous. The optimal control for the satellites is determined. A comparison is made in terms of dimensionality and complexity to a deterministic solution of the rendezvous problem. 相似文献
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针对海军舰载制导弹药MEMS惯导系统在卫星失锁后滚转角误差较大的问题,提出了一种不依赖卫星的制导弹药误差修正算法。根据弹体高速旋转时的定轴性使得短期内弹体侧向位移为零的特点,建立了弹体发射坐标系导航误差方程。利用自适应扩展Kalman滤波估计与修正卫星失效条件下的滚转角误差。为了检测并抑制量测突变引起的随机误差,使用自适应因子来调整滤波器参数。车载模拟试验和弹道仿真结果表明,10s对准时间内,滚转角误差能够收敛到0.5°以内,满足制导弹药控制精度的要求, 降低了制导弹药飞行过程中对卫星导航的依赖,提高了系统的自主性。 相似文献
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The rotation of a spin-stabilized satellite employing a turnstile antenna for reception and retransmission affects two-way Doppler range-rate measurements. Two different types of tracking systems are considered and, in both systems, the range-rate measurement is changed by the amount begin{equation*} |Delta dot{r}| = frac{|1 pm 1/k|}{2} lambda_{t}f_{s} end{equation*} where k is the turn-around ratio of the satellite transponder, Xt is the wavelength of the ground-based transmitter, and fs is the spin rate of the satellite. The positive sign is used if the turnstile antenna elements are connected to give the same polarization for both reception and transmission. If the antenna connections result in different polarizations, the minus sign is used and the magnitude of the effect is reduced. 相似文献
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Cheng P.H.W. Georganas N.D. Holbrook J.A.D. 《IEEE transactions on aerospace and electronic systems》1977,(3):236-245
lt is necessary to maintain the spin axis of dual-spin geostationary communications satellites with nontracking ground antennas to within 0.1 degree of the orbit normal by periodic attitude corrections. Normally, the data for attitude estimation are determined from the analog sensor waveforms telemetered to the ground station. This information is supplied to the attitude determination program, which processes the data and outputs the right ascension and declination of the spin axis. An application of the extended Kalman/ filter in estimating the attitude of dual-spin geostationary satellites is presented. The precession of the angular momentum vector by the solar radia-tion torque is considered to be the only natural attitude perturbation. The orbital dynamics are considered to be known and are decoupled from the attitude dynamics. A periodic attitude control policy is then derived. 相似文献
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A series of tests to validate an antenna pointing concept for spin-stabilized satellites using a data relay satellite is described. These tests show that proper antenna pointing on an inertially stabilized spacecraft can lead to significant access time through the relay satellite even without active antenna pointing. We summarize the test results, the simulations to model the effects of antenna pattern and space loss, and the expected contact times. We also show how antenna beam width affects the results. 相似文献
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C频段统一测控系统非相干测速功能探讨 总被引:1,自引:0,他引:1
针对目前国内C频段统一测控系统因不具备测速功能,在发遥控期间无法进行测距,导致其无法对卫星进行连续轨道测量的缺陷,提出了非相干测速方法。非相干测速利用卫星遥测信息中的上行载波多普勒信息以及地面站获取的下行载波多普勒信息,计算得到双向多普勒信息,对双向多普勒进行计算可获得连续的卫星运动速度信息。本文在理论上证明了这种方法的可行性,并以自旋式卫星同步控制过程中天地时延精确修正为例,说明了这种方法的应用价值。 相似文献
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The variation of mass,and moment of inertia of a spin-stabilized spacecraft leads to concern about the nutation instability.Here a careful analysis on the nutation instability is performed on a spacecraft propelled by solid rocket booster (SRB).The influences of specific solid propellant designs on transversal angular velocity are discussed.The results show that the typical SRB of End Burn suppresses the non-principal axial angular velocity.On the contrary,the frequently used SRB of Radial Burn could amplify the transversal angular velocity.The nutation instability caused by a design of Radial Burn could be remedied by the addition of End Burn at the same time based on the study of the combination design of both End Burn and Radial Burn.The analysis of the results proposes the design conception of how to control the nutation motion.The method is suitable to resolve the nutation instability of solid rocket motor with complex propellant patterns. 相似文献