Exchanging Databases with Dissimilar Systems Using CCSDS XTCE CCSDS Spacecraft Monitoring & Control WG And OMG Space Domain Task Force Presented by Mario Merri, ESA

GSAW Outline Where does XTCE come from? Its goals and benefits How does it work? Usage so far Conclusions

GSAW XTCE History Object Management Group (OMG) standard originally developed by European Space Agency US Air force/Mission Operations (Lockheed Martin) Boeing Communications & Satellites NASA & JPL Being adopted by CCSDS via Agency Review under responsibility of SM&C WG

GSAW CCSDS SM&C and XTCE ESA –M Merri (chairman), M Schmidt, A Ercolani, J Muller –I Dankiewicz, S Cooper BNSC –R Thompson (deputy chairman), B Harnett CNES –B Béhal, E Poupart, R Soumagne CSA –P Melanson DLR –H Hofmann INPE –PG Milani, AM Ambrosio JAXA –T Yamada NASA/GSFC –DC Lokerson, F Johnson, JK Marquart, JS Gal-Edd, C Fatig, R Jones, K Rice NASA/JPL –A Oyake, P Shames, J Moholt ASI –C Labonia OMG –G Simon (Lockheed Martin), B Kizzort (Harris Corp.) XTCE Splinter Group

GSAW XTCE Goals XML-based non-proprietary standard format for TM/TC databases ►Reduces human errors, ambiguities, confusion, and lost time in difficult, sometimes lossy (painful), conversions between systems

GSAW XTCE Format Exchange between –working teams –missions –systems –agencies ►Reuse database ►Reduce costs Application field Planning Scheduling Command Management Real time Trending Analysis Simulators Spacecraft Manufacturers Instrument Manufacturers

GSAW XTCE Benefits Better interoperation between space agencies and contractors (or any other actor) Lets different philosophies collaborate in one data model –Accepts time division multiplexing, packet TM Separates “pure” telemetry and telecommand data from dedicated/proprietary processing data

GSAW XTCE in a nutshell (1/8) An XML Schema language describing telemetry and telecommand data required for: –Channel (de)coding and frame processing –Data transmission and packaging –Parameters calibrations, alarms, properties –Telecommand definitions, transmissions (pre and post checks) –…

GSAW XTCE in a nutshell (2/8) XTCE describes a “SpaceSystem” - command & telemetry descriptions, in a hierarchical format The granularity of a space system’s description is left to the user, e.g. SpaceSystem may contain SpaceSystem(s) That hierarchy allows integration of multiple databases into one overall database –ex: multi-satellite missions, multi-instrument satellite

GSAW XTCE in a nutshell (2*/8) Space System Spacecraft level Instrument level Device level

GSAW XTCE in a nutshell (2**/8) Space System Constellation level Satellite level Instrument level

GSAW XTCE in a nutshell (3/8) A space system in XTCE is able to describe: –Telemetry parameters, their packaging and dedicated processing –Telecommand parameters, commands, its packaging and dedicated processing –Streams (up and down, with coding information) –Maintain minimal configuration information TM and TC definitions are 80% similar

GSAW XTCE in a nutshell (4/8) Header for configuration data Default for generic settings Services for frames identification Telemetry and Telecommand … Space System Header Defaults Telemetry Services Telecommand

GSAW XTCE in a nutshell (5/8) Telemetry data is distributed in several elements: –Parameter types –Parameters (instances of parameter types) –Containers (aka packets) –Messages –Streams –Algorithms

GSAW XTCE in a nutshell (6/8) Logical sequence of definitions : –Parameter types (alarms, calibrations) –Parameter instances –Containers (Packets) –Streams, messages and algorithms Example: CCSDS TM frames, packets and XTCE containers

GSAW XTCE in a nutshell (7/8) Parameters are put in sequence to form packets (containers) Packets are put together to form frames Streams are defined on top of generic frames Frame primary header Frame secondary header Frame data field Op.ctrlErr.ctrl Packet headerPacket data field Ver #TypeP.hdr fAPIDGr. fSSCP.h.len Frame Packet Packet header

GSAW XTCE in a nutshell (8/8) Telecommand data is distributed in several elements: –Parameter types –Parameters –Containers –Messages –Streams –Algorithms

GSAW XTCE Applications so far James Webb Space Telescope XML Schema have been converted SCOS-2000 ASCII files have been converted (other examples?) [ we may want to talk to Harris and Boeing about putting their work in here? –KR]

GSAW CCSDS Documentation Draft CCSDS Green book release along with XTCE1.1 for internal CCSDS review CCSDS Magenta book (detailed user guide) is being written

GSAW Conclusions XML is easy to work with due to the amount of libraries and tools available for it, and its broad industry acceptance XTCE powerful concepts are ideal for represent any legacy system TM & TC database [ that’s may little too strong… but something like that –kr] Non TM&TC data is not considered in XTCE; (dedicated software instructions, SW configuration variables) [ this actually may should be mentioned earlier in XTCE in a nutshell section…-kr]

GSAW Questions and Answers ?