基于智能优化算法的小天体初轨确定  

Initial Orbit Determination Based on Intelligent Optimization Algorithm

作　　者：刘欣 侯锡云[1,2,3] 刘林[1,2,3] 甘庆波[4] 杨志涛 LIU Xin;HOU Xi-yun;LIU Lin;GAN Qing-bo;YANG Zhi-tao(School of Astronomy and Space Science,Nanjing University,Nanjing 210023;Institute of Space Environment and Astrodynamics,Nanjing University,Nanjing 210023;Key Laboratory of Modern Astronomy and Astrophysics,The Ministry of Education,Nanjing 210023;National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101)

机构地区：[1]南京大学天文与空间科学学院,南京210023 [2]南京大学空间环境与航天动力学研究所,南京210023 [3]教育部现代天文与天体物理重点实验室,南京210023 [4]中国科学院国家天文台,北京100101

出　　处：《天文学报》2023年第4期68-88,共21页Acta Astronomica Sinica

基　　金：国家自然科学基金项目(12233003);空间碎片与近地小行星防御科研项目(KJSP2020020205)资助。

摘　　要：经典的初轨确定方法包括Laplace方法和Gauss方法以及它们的各种变化形式.除这些经典方法之外,基于当今光学观测数据的特点,学者们也陆续提出了一些其他的初轨确定方法,包括双r(目标距离观测者的距离)方法和可行域方法.双r方法的一种实现方式是通过猜测某两个时刻(通常是定轨弧段的首、末时刻)目标离观测者的距离,结合观测者在空间中的位置矢量,即可求解相应的Lambert弧段作为目标轨道的初始猜测.进一步,以其他观测时刻的RMS(Root Mean Square)为优化变量可以改进初始猜测从而确定初轨.可行域方法则是针对一组初始观测参数(包括赤经、赤纬及其变率),根据一些初始假设将目标(离观测者的)距离及其变率约束在可行域内,并通过三角划分逐步逼近的方式寻找到使观测RMS最小的猜测解.针对一系列模拟观测数据以及实测数据,将智能优化算法(粒子群算法)应用于这两种初轨方法,并将结果与改进的Laplace算法的结果进行比较.由于双r方法不仅可以用于短弧定轨还可用于长弧关联,所以进一步给出了针对长弧段数据的关联结果.Classical methods for initial orbit determination(IOD)include Laplace method,Gauss method and their variations.In addition to this,based on the characteristic of optical observation data nowadays,experts propose some other IOD methods,like Double-r method and admissible region method.One of the ways to determinate the orbit through double-r method is to guess distances of the target from the observer at two epochs---usually at the first and the last one.By doing so,we can solve the Lambert problem and use its solution as the initial guess of the orbit.Furthermore,we can improve the initial guess by iterations to reduce the root mean square(RMS)of the observations.The admissible method is based on the concept of attributable(longitude,latitude and their rates).With some conceptions,the admissible region described by the range and range rate from the observer is characterized.Using triangulation we can find the nodal point that makes the RMS minimal.In our work,we apply one intelligent optimization method---the particle swarm optimization method to the two methods,based on simulated and real data,and compare the results with that of modified Laplace method.At last,we briefly discuss the possibility of applying the double-r method to the orbit link problem.

关 键 词：天体力学 小天体 方法:数值 

分 类 号：P135[天文地球—天体力学]