联盟TM交会对接的地面远程导引段制导方法分析与研究

就俄罗斯联盟TM 号飞船与和平号轨道空间站交会对接中的远距离接近段所报导的一些数据对其制导方法进行分析与研究。分析与计算结果表明, 采用固定时间燃料最省的四次冲量方法所获得的冲量大小、方向及冲量施加的时间与报导极为吻合     

卫星空间外热流轨道参数ψ_0,Ω_0和ω_0计算

文章给出了卫星热分析空间外热流计算中所需要的轨道参数太阳黄经、升交点赤经和近地点幅角的初值φ_0、Ω_0、ω_0 的计算公式。其精确度满足卫星热分析要求。     

自由飞行段跟踪数据的系统误差估计

连续波雷达是目前外火箭轨道测量的主要高精度设备,用数学方法估计和修正其系统误差有特别重要的意义。根据自由飞行轨道方程准确的特点,利用轨道方程建立了估计自由段系统误差的非线性模型,并给出了求解系统误差和轨道参数估计值的计算方法。运用该方法,只要一套MISTRAM系统的跟踪数据,就能给出自由飞行段常值系统误差的估计。     

用加速度计的积分遥测量计算弹道参数及轨道要素

文章提供利用运载火箭特征点(关机点,入轨点等)的有关加速度计的积分遥测量计算该点的弹道参数和轨道要素的计算方法。     

伴随轨道拟合技术

航天器的伴随轨道可以执行各种特殊任务。文中给出一种从伴随轨道确定两个航天器轨道要素的方法,这一方法也可推广应用于多个航天器的情况。     

降落伞特性对伞舱系统运动稳定性的影响

建立了伞舱系统刚性连接和弹性连接时的数学模型,针对联盟号飞船回收系统进行了动力学仿真。分析了降落伞侧向力系数、吊带长度、降落伞和载荷质量比以及吊带性质对伞舱系统运动稳定性的影响,其结论可为伞舱回收系统的设计提供参考。     

空间目标碰撞概率的显式表达式及影响因素分析

在圆轨道情况下推导了空间目标碰撞概率的显式表达式,将碰撞概率表示为空间目标交会几何条件(过交线高度差、过交线时间差、轨道夹角等)和RSW坐标系误差方差的显式函数.根据显式表达式对碰撞概率的影响因素进行了分析,研究了过交线高度差、过交线时间差、轨道夹角、位置预报误差、等效半径等因素对碰撞概率的影响,得出了一些有意义的结论.     

Simulation software for the spiral trajectory of our Moon

At 4.56 Ga, the accretion of the slowly rotating Solar Nebula led to the formation of Sun and its Planets in the plane of disc of accretion. Moon was formed by accretion from a circumterrestrial disk of debris generated by the glancing angle impact of the young Earth by a Mars size planetary embryo at about 4.5 Ga at a distance of 15,000 km. The Moon since then has migrated to the present position of 384,400 km from the center of the Earth. In course of this outward migration it has slowed down the spin rate of Earth and caused the lengthening of diurnal day length from 5 h initially to 24 h presently. The basic mechanics of Earth–Moon System has been worked out and theoretical determination of lengthening of day curve is carried out. This theoretical lengthening of day curve is compared with the observed lengthening of day curve based on paleobotanical evidences, ancient tidalites and Australian Banded Iron Formation. There is a remarkable correspondence between the two curves except for intermittent deviations due to geographical and geophysical factors. Based on the theoretical curve of lengthening of day, an empirical formula for the lunar orbital radius expansion is determined. Based on this empirical formula, simulation software is developed that gives the correct evolution of the semi-major axis (a) of our Moon for any time span from the inception to the time chosen under study. For mathematical simplicity the system is considered to be a two body rotating system throughout its evolutionary history of 4.5 Gyrs. This simulation draws the Moon’s spiral trajectory from its inception to any subsequent epoch. The terminal epoch is an input to the simulation software to arrive at the spiral trajectory of the Moon from the inception to the given epoch. The basic mechanics of Earth–Moon System and this simulation can be generalized to lay the foundation of simulation software for any Planet–Satellite pair or any Sun-Planet pair in our Solar System or Star-Planet pair in any Extra-Solar System. The basic dynamics has been found to be valid for Star–Planet pair also. So this Simulation Methodology can as well be applied to study the migratory evolution of Gas Giants also.     

飞控系统实时仿真算法分析

采用改进的双线性变换方法－临界频率预翘曲方法,对双线性变换方法引起的偏差进行预补偿,从而减小飞控系统的实时仿真误差。以频带较宽的典型环节为例,对系统频率特性进行了分析,同时,将其与双线性变换及四阶龙格－库塔法的计算结果进行了比较。结果表明：该方法能较好地补偿双线性变换所引起的误差,满足飞机飞控系统的实时仿真要求。     

涡轮流量计动态响应特性校准技术研究

涡轮流量计传统上只进行稳态校准,即只校准其（稳态）仪表系数,本文阐述了校准涡轮流量计动态响应特性的理论和实施方法。