随着空间科学技术的发展，空间任务的执行已经由单一航天器发展为多个航天器组成的航天器编队，同时带动一系列具有重要应用价值的通用性技术的发展，其中就包括了分布式合成孔径光干涉成像技术。该技术使用的分布式平台由航天器编队承载，通过将平台中保持相同指向、处于同一平面且确定相对姿态的各个子径收集到的光波进行合光，实现对遥远星体的成像。因此该技术对航天器编队的测量系统提出了非常严苛的要求，其中包括星间距离、星间相对位置的测量。测量系统中涉及的高精度检测算法和模型需要经仿真验证后才能被应用于实际。

仿真技术在航天领域中一直都发挥着重要的作用，如今更是发展到了虚拟仿真的阶段，动画仿真、可交互仿真等应用越来越广泛。针对航天器编队高精度检测算法的仿真和验证需求，本文设计并搭建了一个面向航天器编队高精度检测算法仿真、三维可视化航天器编队仿真任务情景和仿真结果的软件平台。该平台能够动态地展示航天器编队轨道执行任务的过程，可根据不同任务需求对编队构型进行设置，同时在三维可视化环境中将高精度检测算法中涉及的参数进行展示，且能实现算法仿真运行结果的动态展示。

本文首先简要阐述了航天器编队高精度检测算法的基本原理，由此引出了虚拟仿真平台的软件需求，并对应提出了平台的总体架构和各模块功能的设计。虚拟仿真平台由WPF开发的主控软件和多个由Unity开发的虚拟仿真场景组成。

主控软件是虚拟仿真平台的控制中心，也是用户进行虚拟仿真的软件本体。本文首先设计了基于C/S架构且支持TCP和UDP两种通信协议的进程通信模块，实现了主控软件和各个场景程序间的数据互通功能；其次，开发了支持MATLAB COM和.Net程序集两种C#调用MATLAB方式的MATLAB计算模块为高精度检测算法提供了仿真计算的环境；然后，开发了Unity场景管理模块，能够实现主控软件对Unity场景的集成和控制的功能；最后，开发了支持仿真平台数据持久化的仿真项目管理模块，能够将用户进行虚拟仿真时涉及的相关数据进行维护和管理，确保仿真项目数据的完整性和安全性。

虚拟仿真场景是平台进行三维可视化的演示中心。本文首先介绍了Unity场景开发涉及的脚本生命周期和协同程序的技术理论；其次，根据各个Unity场景的需求，开发了各个场景中通用的脚本，包括集成了控制物体运动行为的协程马达架构、支持客户端进程通信的脚本以及支持播放物体运动过程的播放器架构；然后，根据各个场景具体的需求，开发了模拟航天器编队在轨执行任务的轨道仿真场景、模拟航天器编队内主从星相对变化的编队构型场景和对高精度检测算法中使用的参数进行三维可视化展示的测距场景。

最后本文对虚拟仿真平台各个部分的功能分别开展了测试，并对平台进行了总体的仿真测试，测试的结果表明：平台能够满足高精度检测算法的仿真需求，且可将算法仿真对应的航天器编队任务情景进行三维可视化的逼真展示。

With the development of space science and technology, the execution of space missions has developed from single spacecraft to spacecraft formations composed of multiple spacecraft, which has driven the development of a series of universal technologies with significant application value, including distributed synthetic aperture optical interference imaging technology.The distributed platform utilized by this technology is carried by the spacecraft formation, which collects the light waves from various sub-apertures that maintain identical pointing, lie in the same plane, and possess determined relative orientations within the platform, and coherently combines them to achieve imaging of distant celestial bodies. Therefore, this technology imposes extremely stringent requirements on the measurement system of spacecraft formation, including the measurement of inter-satellite distances and inter-satellite relative positions. The high-precision detection algorithms and models involved in the measurement system need to be verified by simulation before being applied in practice.

 

Simulation technology has always played an important role in the aerospace field and has now developed to the stage of virtual simulation,  where animation simulation, interactive simulation and other applications are becoming increasingly widespread.To meet the simulation and verification requirements of high-precision detection algorithms for spacecraft formations, this paper designed and constructed a software platform for simulating high-precision detection algorithms for spacecraft formations, 3D visualization of spacecraft formation simulation scenarios, and simulation results. The platform is capable of dynamically displaying the process of spacecraft formation executing missions in orbit, and configuring the formation configuration according to different task requirements, it also displays the parameters involved in the high-precision detection algorithm in a 3D visualization environment, and dynamically displays the simulation results of the algorithm.

 

This paper first briefly elaborates on the basic principles of high-precision detection algorithms for spacecraft formation, which leads to the software requirements of the virtual simulation platform, and correspondingly proposes the overall architecture of the platform and the design of each module function. The virtual simulation platform consists of a main control software developed using WPF and multiple virtual simulation scenes developed using Unity.

 

The virtual simulation platform consists of a main control software developed using WPF and multiple virtual simulation scenes developed using Unity.

The main control software servers as the control center of the virtual simulation platform and is also the software entity for users to conduct virtual simulations. This paper first designed a process communication module based on the C/S architecture and supporting both TCP and UDP communication protocols, which achieves the data exchange function between the main control software and various scene programs. Additionally, a MATLAB computation module was developed to provide a simulation environment for high-precision detection algorithms, which supports both MATLAB COM and .Net assembly invocation of MATLAB in C#. Furthermore, a Unity scene management module was developed,  which enables the integration and control of Unity scenes by the main control software. Lastly, a simulation project management module that supports simulation platform data persistence was developed, which can maintain and manage the relevant data involved in user virtual simulation, ensuring the integrity and security of the simulation project data.

 

The virtual simulation scene serves as the demonstration center for three-dimensional visualization on the platform. This article first introduced the technical theory of script life cycle and coroutine involved in Unity scene development. Additionally, according to the requirements of each Unity scene, universal scripts were developed for each scene, including a coroutine motor architecture that integrates the control of object movement behavior, a script that supports inter-process communication, and a player architecture that supports playing the process of object movement. Furthermore, specific to the requirements of each scene, the orbital simulation scenario of simulating the spacecraft formation executing tasks in orbit, the formation configuration scenario simulating the relative changes between the primary and secondary spacecrafts in the spacecraft formation, and the ranging scenario for three-dimensional visualization of the parameters used in the high-precision detection algorithm were developed.

 

Finally, this article conducted individual tests on the functionalities of various components of the virtual simulation platform, and then performed an overall simulation test of the platform. The test results indicate that the platform is capable of meeting the simulation requirements of high-precision detection algorithms, and can realistically display the corresponding spacecraft formation mission scenarios of algorithm simulation through three-dimensional visualization.

[1] 吴季. 空间科学任务及其特点综述[J]. 空间科学学报, 2018, 38(02): 139-146.
[2] 尤亮, 白青江, 孙丽琳等. 世界主要空间国家空间科学发展态势综述[J]. 中国科学院院刊, 2015, 30(06): 740-750.DOI:10.16418/j.issn.1000-3045.2015.06.004.
[3] 孙俊, 黄静, 张宪亮等. 地球轨道航天器编队飞行动力学与控制研究综述[J]. 力学与实践, 2019, 41(02): 117-136.
[4] 中国航天透露“觅音计划”，将探索系外宜居行星[J]. 卫星与网络, 2019(12): 74.
[5] 寻找另一个地球[J]. 少年电脑世界, 2020(04): 20-23. 赵凯华, 罗蔚茵. 新概念物理教程: 力学[M]. 北京: 高等教育出版社, 1995.
[6] Mimi Aung, Asif Ahmed,etc. An Overview of Formation Flying Technology Development for the Terrestrial Planet Finder Mission[C]. 2004 IEEE Aerospace Conference Proceedings. 2667-2679.
[7] G. Mark Brown, Clyde F. o Quinn, etc. Requirement Analysis for a multi-spacecraft flight system[J]. 2002 IEEE. 767-782.
[8] Kenneth H. Lau. Formation flying technologies and Approach for the Nasa ST3 Mission[C]. 15th Internation Symposium of Spaceflight Dynamics, June 2000.
[9] E. G. Lightsey. Development and Flight Demonstration of a GPS Receiver for Space[J]. Dept. of Aeronautics and Astronautics. Stanford University, Stanford,CA, 94035. Jan, 1997.
[10] K. Lau. S. Lichten. L. Young, ect. Annovative deep space application of GPS technology for formation flying spcaecraft[C]. Proceedings of the AIAA GNC Conference. San Diego, CA. July, 2000.
[11] Mallory, G. J., Jilla, C. D., Miller, D. W., Optimization of Geosynchronous Satellite Constellations for Interferometric Earth Imaging[C], AIAA/ASS Astrodynamics Specialists Conference, August 1998.
[12] 徐爱民. 分布式卫星干涉仪轨道设计[D]. 解放军信息工程大学,2009.
[13] 康凤举. 现代仿真技术与应用[M]. 北京：国防工业出版社, 2006.
[14] 孙杰. 计算机虚拟仿真技术发展与创新[J]. 中国宽带, 2020(10): 69-70.
[15] 马梦威. 三维自动测试系统虚拟仿真平台的设计与实现[D]. 电子科技大学, 2022.DOI:10.27005/d.cnki.gdzku.2022.001549.
[16] 吴家铸. 视景仿真技术及应用[M]. 西安: 西安电子科技大学出版社, 2001.
[17] 朱雨香. 视景仿真技术的研究与实现[D]. 南京: 南京理工大学, 2004.
[18] 张云彬, 张永生. STK/Connect 模块分析与应用[J]. 测绘学院学报, 2001, 018(B09): P.29-32.
[19] Cyril X. ROSESAT-A GRAPHICAL SPACECRAFT SIMULATOR FOR RAPID PROTOTYPING[C]. Space Ops98 Symposium. 1998.
[20] Perryman M A C , De Boer K S , Gilmore G , et al. GAIA: Composition, formation and evolution of the Galaxy[J]. Astronomy & Astrophysics, 2001, 369(1):339-363.
[21] Jonckheere R K D, Franklin T L, Wilson D D. Spacecraft Simulation Toolkit (SST): an advanced distributed simulation framework for supporting the space warfighter[J]. Proceedings of Spie the International Society for Optical Engineering, 1997.
[22] Bai X, Wu X. A simulation and visualization platform for fractionated spacecraft attitude control system[C]. 2011 IEEE International Conference on Mechatronics and Automation. IEEE, 2011: 2033-2038.
[23] Ilk Valentin, Ewald Reinhold, Bosch Bruguera Miquel. Implementation of a Spacecraft Cockpit in a Virtual Reality Environment[J]. 2019.
[24] 赵沁平, 沈旭昆, 夏春和. DVENET:一个分布式虚拟环境[J]. 计算机研究与发展, 1998(12): 1064-1068.
[25] 王超, 王民, 郭秀红. 航天飞行动力学仿真模型验证环境研究[J]. 航天器环境工程, 1997(4): 42-45.
[26] 李勇. 航天器运动可视化分析系统的设计与实现[D]. 湖南: 国防科学技术大学, 2002.
[27] 陈培, 韩潮. 基于 dSPACE 和 xPC 的分布式航天器准实时仿真系统[J]. 系统仿真学报, 2006, 17(z2):53-57.
[28] Zhou J, Yuan J, Luo J, et al. Development of Distributed General Integrated Navigation Simulation Platform for Spacecraft[J]. Journal of System Simulation, 2008, 19.
[29] 姚红, 汤亚锋, 胡敏. 基于 xPC 的航天器电磁编队控制系统实时仿真研究[C]. Chinese Conference on System Simulation Technology & Application. 2012.
[30] 孙诗行, 宗群, 徐锐. 基于OGRE的卫星视景仿真软件的设计与实现[J]. 计算机应用与软件, 2016, 33(10): 203-206.
[31] 谷友博. 航天器虚拟仿真验证平台的设计与实现[D]. 天津大学, 2020. DOI:10.27356/d.cnki.gtjdu.2020.004402.
[32] 秦航. 软件设计和体系结构[M]. 北京：清华大学出版社, 2014.
[33] Technologies Unity. Unity 5.x从入门到精通[M]. 中国铁道出版社, 2016.
[34] 王唯融. 基于WPF框架的自定义控件集设计与实现[D]. 西安电子科技大学, 2014.
[35] 王鹏, 崔静. 新一代界面技术WPF的架构及应用[J]. 成都纺织高等专科学校学报, 2011, 01, 18-20.
[36] [美] Chris Anderson. WPF核心技术[M]. 朱永光译. 北京: 人民邮电出版社, 2009: 22-23.
[37] 蒋一凡. 基于3ds Max和Unity3D的虚拟仿真教学实验的开发研究[D]. 延边大学, 2020. DOI:10.27439/d.cnki.gybdu.2020.001186.
[38] 张峰峰. BIM技术在大型冶金工程中的实际应用[J]. 科技经济导刊, 2018,26(26): 50.
[39] 李孟达, 杜汉强, 张丽丽. 3dsMax建模及轻量化在河钢唐钢三维工厂运维仿真的应用[J]. 工业技术与职业教育, 2022,20(06): 3-5. DOI:10.16825/j.cnki.cn13-1400/tb.2022.06.017.
[40] 张思聪. 基于三层架构的分布式电动汽车充电运营管理系统[D]. 合肥工业大学, 2017.
[41] 付林强. 基于三层架构的插件体系结构设计[D]. 电子科技大学, 2013.
[42] 严谦, 阳泳. 网络编程TCP/IP协议与Socket论述[J]. 电子世界, 2016(08): 68-70.
[43] 柒玉强. TCP/UDP协议数据高速国密加解密系统设计与实现[D]. 燕山大学, 2019. DOI:10.27440/d.cnki.gysdu.2019.000363.
[44] 李会民, 颜明会, 任红彬等. 基于UDP协议实现数据安全、高效传输的方法研究[J]. 北华航天工业学院学报,2022, 32(06): 8-10.
[45] 雷津, 赵寅. VC++环境下的UDP网络通信实现[J]. 电子测试，2017(13): 36-38.
[46] 王少辉, 陈晓鹏. 基于Java的socket I/O流技术[J]. 电子技术与软件工程, 2017, 000(009): 30-31.
[47] 刘杰, 陈泽志. 基于Matlab的样条插值[J]. 航空计算技术2003, (3): 39-42.
[48] 秦春影,喻晓锋,仝海燕等. 三种C Sharp调用Matlab方式的研究[J]. 菏泽学院学报, 2012,34(02): 35-38.DOI:10.16393/j.cnki.37-1436/z.2012.02.022.
[49] 周卫. Matlab在测绘中的应用[J]. 城市测绘, 2001, (3): 13-17.
[50] 申光. 基于COM组件的案事件管理信息系统的研究及实现[D]. 长沙: 中南大学, 2003.
[51] 张望. 一种基于COM的改进组件创建的研究[D]. 重庆: 西南大学, 2010．
[52] 赵新昱, 郭兵兵, 陈文伟． COM组件属性、方法的自动提取和调度[J]． 计算机工程， 2000，(11): 12-13．
[53] 丁国兴, 高琴, 高伟. 基于Win32 API的通用串口通信组件的开发[J]. 工业控制计算机, 2013, 26(11): 33-35+37.
[54] 贺军, 李喜梅. ASP.NET 中 Visual Basic.NET、JavaScript.NET和C#语言的区别[J]. 长春师范大学学报, 2004, 23(5): 40-44
[55] 石露. 基于Unity3D跨平台坦克虚拟驾驶视景仿真系统的研究[D]. 西安电子科技大学,2020.DOI:10.27389/d.cnki.gxadu.2020.002763.
[56] 石岩. FPS游戏的设计实现及其性能优化算法研究[D]. 北京林业大学, 2018. DOI:10.26949/d.cnki.gblyu.2018.000477.