AAS 01061999 AIML

44 %
56 %
Information about AAS 01061999 AIML

Published on November 16, 2007

Author: miloung

Source: authorstream.com

Slide1:  Using XML for Instrument Description, Communication and Control of the SOFIA / HAWC Instrument Troy J. Ames Advanced Architectures and Automation Branch NASA/Goddard Space Flight Center, Code 588 Troy.J.Ames.1@gsfc.nasa.gov (301) 286-5673 Kenneth B. Sall and Craig E. Warsaw Century Computing, Inc. ksall@CenturyComputing.com, cwarsaw@cen.com (301) 953-3330 IRC-010699 193rd Meeting of the American Astronomical Society Austin, Texas January 6, 1999 Sponsor: Dr. Richard Shafer, NASA/GSFC Richard.A.Shafer.1@gsfc.nasa.gov (301) 286-3463 http://pioneer.gsfc.nasa.gov/public/irc/ Background:  Background Instrument Remote Control (IRC) began as a small prototyping effort for CARA at the South Pole in late 1997. Developed a distributed architecture and Graphical User Interface to remotely control heaters attached to telescope. Early 1998: Idea to describe instrument control via XML (Extensible Markup Language). Mid 1998: Began SOFIA HAWC effort. Goals:  Goals Enabling access of infrared astronomical instruments located in remote, inhospitable environments. Configurable software architecture supporting instrument remote control. Easy to develop, modify, maintain, extend. Distributed - assign processes to different computers, regardless of operating system. SOFIA HAWC Prototype:  SOFIA HAWC Prototype HAWC PDR - early October 1998. Initial Java and XML prototype was developed by mid December 1998. Simulates commands and responses from telescope, ADR (refrigeration), opto-mechanical, and detector subsystems. Runs quick look and other data reduction algorithms as inputs to visualizations. Uses XML to describe cmds, basic GUI. Eventually will use XML for responses, pipeline algorithms, and more. Design Solution:  Design Solution Software driven by XML-based Instrument Description GUI, command set, command formats data pipeline algorithm descriptions data streams (responses, images) online help and documentation eventually from hardware engineers (ICDs) Publishers and Subscribers visualizations subscribe to data from pipeline algorithms XML, AIML, IML ...:  XML, AIML, IML ... Astronomical Instrument Markup Language (AIML) is the initial focus of the more general Instrument Markup Language (IML). AIML and IML are under development by NASA/GSFC and Century Computing. Dialects such as PAML (Pipeline Algorithm ML) and IGS (Instrument GUI Stylesheet [XSL]) will be added in the near future. Coordinate with D. Guillaume for image markup: Astronomical Markup Language (AML). Benefits:  Benefits Clearly defined interface between hardware and software engineers. Easy to make last-minute changes in AIML description that are incorporated throughout the system. Clean separation of implementation (representation) from description. Leverages latest Java and XML technology; many more capabilities expected in 1999 (from Sun, IBM, W3C). Technologies:  Technologies XML: Extensible Markup Language XML parser, APIs, editor, browser Bean Markup Language (scripting, GUI) XSL: Extensible Style Language Java (Swing, JavaBeans) UML: Unified Modeling Language Object Oriented Design and Analysis IDL and other Data Reduction software Browsing/Editing AIML:  Browsing/Editing AIML The JUMBO browser was originally developed for the Chemical Markup Language. Appendices:  Appendices XML Information Applicability of XML to Instrument Remote Control Web Sites and Email List What is XML?:  What is XML? XML = Extensible Markup Language a web standard: a World Wide Web Consortium “Recommendation” (February 1998) human readable data format: visually similar to HTML, but closer to SGML (Standard Generalized Markup Language) structured (hierarchical) data, any degree of complexity database neutral format verifiable: can be validated for correctness/integrity extensible: meta language used to define other domain- or industry-specific languages (mathematical, chemical, biological, publishing, etc.) by supplying a specific Document Type Definition (DTD; like Backus-Naur Form) media independent: describes data, not visual presentation interoperable: platform and vendor independence Presentation vs. Structure:  Presentation vs. Structure HTML: Only reflects how text should be presented. Not obvious to computer that “Public” is a last name, or even that we’re referring to an employee. <B>John Q Public</B><BR> <I>john.q.public.1@gsfc.nasa.gov<I> XML: Only indicates how information is structured. Employee and Last name are obvious, but how we display this info is not specified, so different applications can display pieces as per their own requirements. <EMPLOYEE> <NAME> <FIRST>John</FIRST> <MIDDLE>Q</MIDDLE> <LAST>Public</LAST> </NAME> <EMAIL>john.q.public.1@gsfc.nasa.gov</EMAIL> </EMPLOYEE> John Q. Public john.q.public.1@gsfc.nasa.gov ??? XML and Java:  XML and Java “XML can do for data what Java has done for programs, which is to make the data both platform-independent and vendor-independent.” Jon Bosak, Sun Microsystems Chair of W3C XML Working Group Media-Independent Publishing: Four Myths about XML http://dlib.computer.org/co/books/co1998/pdf/rx120.pdf IEEE Computer, Volume 31, Number 10 (October 1998) Applicability of XML to IRC:  Applicability of XML to IRC Astronomical Instrument Description (AIML) Instrument Characteristics filters, detectors, sensitivity, sub-components, component interdependencies, etc. Control Capabilities (what instrument can do) Data Stream Descriptions images (data collection and data reduction pipeline) housekeeping (instrument status, health and safety) command responses Message Formats (e.g., API to devices) separate formats for Control and Data Streams Communication Mechanisms (e.g., TCP, RS232) Pipeline Algorithm Description (PAML) algorithm inputs and outputs connecting pipeline steps XML Applicability (cont’d):  XML Applicability (cont’d) Metadata (see example) Documentation a la javadoc (template with specific style applied) novice vs. expert levels of documentation investigator, operator, or astronomer role-specific documentation short descriptions - GUI, tool tips long descriptions - paragraphs for on-line help Style and Presentation (Instrument GUI Stylesheet) XSL for GUI components and eventually layout if XML contains a range of values --> generate slider (scale) if XML contains enumerated choices --> list or radio buttons Down the road… Planning Observations (“proposals”) - what observ. match? Scheduling Instruments for Observations timing constraints, hardware limitations, etc Metadata Example:  Metadata Example <Image> <Data href=“m42th1a.fits” type=“FITS” series=“1247”/> <Metadata> <ObjectName>M42, Orion Nebula, Theta-1</ObjectName> <TimeStamp> <Date month=“09” date=“16” year=“2001” /> <Time hrs=“17” min=“24” sec=“13” msec=“145” /> </TimeStamp> <Integration duration=“20” filter=“300micron” /> <FlightInfo ra=“5:33” dec=“5:25” /> <Notebook>This stellar image was taken on our maiden voyage...Weather conditions were... </Notebook> </Metadata> </Image> Email and Web Sites:  Email and Web Sites XML for Astronomy mail list/archive mail to majordomo@pioneer.gsfc.nasa.gov subscribe xml your_email_address Relevant web sites: SOFIA: http://sofia.arc.nasa.gov/ IRC: http://pioneer.gsfc.nasa.gov/public/irc/ HAWC: http://pioneer.gsfc.nasa.gov/public/hawc/ AIML: http://pioneer.gsfc.nasa.gov/public/aiml NASA/GSFC, Advanced Architectures and Automation Branch (Code 588): http://aaaprod.gsfc.nasa.gov/website/ Century Computing: http://www.CenturyComputing.com/ XML info at Web Developer’s Virtual Library: http://WDVL.com/ (or http://Stars.com)

Add a comment

Related presentations