基于RTS2的自动DIMM系统的实现

发布时间：2018-02-23 23:19

本文关键词： 大气视宁度 ADIMM RAO RTS2 自主观测自动寻星指向　出处：《中国科学院研究生院（云南天文台）》2014年硕士论文　论文类型：学位论文

【摘要】：天文台站观测环境的长期监测一直是很重要的研究内容，为正常有效地进行天文观测提供了必不可少的技术支持，于是，如何建立完整高效的站址监测系统便成为了研究人员的研究方向之一。天文观测站址监测系统主要包括了大气视宁度监测、气象信息监测、全天云量监视等等[41]，这其中的大气视宁度监测是非常重要的一部分，对评估天文观测台站的观测条件好坏起到了非常重要的作用。大气视宁度一般用大气光学相干长度r0来表述，是现今使用最广泛的体现大气视宁度的参数。测量计算大气光学相干长度r0的方法有很多种，其中最具代表性也应用最广泛的是差分像运动法，该方法通过测量星像相对位置的变化来计算出r0值，能够非常有效地排除掉非大气因素对大气视宁度测量的影响。差分像运动大气视宁度监测仪（Differential Image Motion Monitor，DIMM）就是以此原理来设计研制的，DIMM将单一目标源经过两个子瞳在CCD上成两个星像，通过测量这两个星像相对距离变化的方差来计算大气视宁度参数r0，消除了仪器抖动等非大气因素的影响，使得测量结果更加可靠。目前世界上DIMM的使用已经较为普遍，其作为天文台站监测和天文选址的工具发挥了重要的作用。由于天文台站一般在较偏远的地区或者高原地区，环境气候比较恶劣，于是由人员值守DIMM进行观测就变得非常艰苦，特别是在南极站点，值守观测更加是不现实的。这样一来，将DIMM实现自动化（ADIMM），让其自主进行观测就成为了非常必要的目标。要实现DIMM自动化，需要借助近年来发展迅速的程控自主天文台技术，并以此技术为支撑平台来进行设备开发。程控自主天文台（RoboticAutonomous Observatory，RAO）是一套能够执行各种观测任务，并且能够在任务执行过程中没有任何人为协助的情况下自主适应各种环境变化的望远镜系统，其具有自动、无人的特点。程控自主天文台的技术为差分像运动大气视宁度监测仪的自动化奠定了基础，，全自动化也是DIMM发展的一个重要趋势。为了高效地对DIMM设备进行操作控制，采用了一套基于Linux平台的集成化开源程控自主天文台控制系统，远程望远镜控制系统第二版（RemoteTelescope System2nd，RTS2）进行自动DIMM的研究，具有较强的创新性。RTS2系统就是以全自动为开发目标，具有环境自主监测、观测目标自主选择、自主观测、自主适应环境变化等优点。RTS2系统在设计与实现上具有非常强的模块性，能够很方便地启用与关闭其中的某个模块，设备切换快捷，系统响应非常快速。采用RTS2系统来实现ADIMM，能够充分利用这套先进望远镜系统的优点，高效地对硬件设备进行控制，也能够以此掌握RTS2系统的关键技术，实现自主开发自动远镜控制软件技术上的突破。基于RTS2的ADIMM系统，根据其程控自主的特点，在硬件配置上需要具备以下三个部分：环境监测部分，包含了气象站、云量传感器以及圆顶；观测设备部分，包含了主望远镜、寻星镜、相应CCD以及子瞳罩；控制部分，包含了控制计算机、RTS2与所有硬件设备的连接配置。在软件控制上需要具备以下五个部分：自动寻星、指向、自动导星、图像处理与视宁度计算。在以上所示的软硬件包含内容中，环境监测部分中的气象站给RTS2系统提供实时的气象信息，云量传感器给RTS2系统提供实时的云量信息，以这些信息来判断是否打开圆顶开始观测或者关闭圆顶结束观测。观测设备部分中的寻星镜及相应CCD负责辅助望远镜进行精确指向，通过寻星镜CCD先将目标星导至寻星镜视场中央，再通过主望远镜CCD将目标星导至主视场中央，然后主望远镜CCD开始曝光获取DIMM图像。在控制计算机的ubuntu操作系统中安装有RTS2系统，并在RTS2系统中完成了对所有硬件设备的通信连接配置，以便能够使用RTS2对硬件设备进行控制。软件开发部分中的自动寻星功能能够综合一系列因素给所有可观测目标星计算权值，然后选取权值最高的目标星并完成指向，最后开始曝光获取DIMM图像，并执行自动导星，以及图像处理与视宁度计算来获取大气视宁度数据。
[Abstract]:Long term monitoring station environment Observatory has is very important to study the contents, provide the necessary technical support for normal astronomical observations so effectively, how to establish a complete and efficient site monitoring system has become one of the research directions of the researchers. The monitoring system mainly includes the day observation site seeing monitoring. Weather information monitoring, cloud monitoring and so on [41] all day long, the atmospheric seeing monitoring is a very important part of the quality assessment of astronomical observation condition observation station plays a very important role.
Seeing the atmospheric optical coherence length R0 is generally used to describe, is the most widely used as a parameter reflecting the atmosphere. Ning of measurement method of atmospheric optical coherence length calculation of R0 has many kinds, among which the most representative is the most widely used is the differential image motion method, change the method by measuring the stars like the relative position to calculate the R0 value, can effectively eliminate non atmospheric factors of Ning measurement of the atmosphere. The differential image motion monitor (Differential Image Motion Monitor, DIMM) to design is based on this principle, DIMM single target source after two into sub pupil like two stars in the CCD, by measuring the relative variance of two star like distance change to calculate the seeing parameter R0 atmosphere, eliminates the influence of instrument jitter of non atmospheric factors, makes the measurement results more reliable.
The use of DIMM in the world has been more common, as the observatory station monitoring and astronomical site tools play an important role. Because the observatory station in more remote areas or plateau, climate is relatively poor, so the staff on duty DIMM for observation becomes very difficult, especially in the Antarctic site, unattended observation more is not realistic. As a result, the DIMM automation (ADIMM), the independent observations have become very necessary. In order to realize DIMM automation, with rapid development in recent years programmable autonomous Observatory technology, and this technology as the support platform for equipment development.
SPC (RoboticAutonomous Observatory, RAO autonomous Observatory) is a set to be able to perform a variety of tasks and observation, in the task execution system self adapt to environmental change telescope without human assistance in the process of case, it has automatic, unmanned technology. Robotic autonomous Observatory has laid the foundation for poor automation such as sports atmosphere seeing monitor, full automation is an important trend in the development of DIMM.
In order to control the operation of the DIMM equipment efficiently, using a set of control system of Linux platform based on open source integrated programmable autonomous Observatory, remote control telescope system version second (RemoteTelescope System2nd, RTS2) of automatic DIMM, innovative.RTS2 system is strong to automatic target for development, with independent environment the observation of the target monitoring, self selection, self observation, self adapt to environmental change and other advantages of the.RTS2 system module has very strong in design and implementation, can easily enable a module of the switching equipment and closing fast, very fast response system. Using RTS2 system to realize the ADIMM, can take advantage of this set of advanced telescope system, to control the hardware efficiently, also able to master the key technology of RTS2 system, realize the independent development of automatic telescope A technological breakthrough in controlling software.
The ADIMM system based on RTS2, according to the characteristics of the program independent, in the hardware configuration has the following three parts: the part of environmental monitoring, including meteorological station, cloud sensor and dome observation equipment; part contains the main telescope finder, and the corresponding CCD sub pupil mask; control part, including control of computer, RTS2 connection configuration with all hardware devices. In software control has the following five parts: automatic control, automatic guide, pointing, image processing and seeing the calculation.
The hardware and software are shown in the above contents, the environmental monitoring part of the weather station to the RTS2 system to provide real-time weather information, cloud sensor to the RTS2 system to provide real-time information to the cloud, the information to determine whether to open or close the dome dome began observing the end of observation. Finder observation equipment and corresponding part CCD is responsible for the auxiliary telescope pointing to the finder, CCD first target star finder to guide the center of the field, then the main telescope CCD will target star guide to the main field of the central, then the main telescope CCD exposure DIMM image acquisition. RTS2 system is installed in the Ubuntu operating system control computer, and complete the connection all the hardware configuration to communication equipment in the RTS2 system, in order to be able to use RTS2 to control the hardware. Software development is part of the automatic control function can be integrated A series of factors calculate weights for all observable target stars, then select the target star with the highest weight and finish pointing, and finally get exposure to get DIMM images, and execute automatic guiding stars, and image processing and visibility calculation to get atmospheric visibility data.

【学位授予单位】：中国科学院研究生院（云南天文台）
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：P112

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