Orbiter* Architecting Software Across International Partnerships. Jason LaPointe December 10 th, 2010

Transcription

1 ExoMars/Trace Gas Orbiter* Architecting Software Across International Partnerships Jason LaPointe December 10 th, 2010 Jet Propulsion Laboratory California Institute of Technology Pasadena, CA 2010 Workshop on Spacecraft Flight Software * Proposed Mission. Pre-decisional - for planning and discussion purposes only 2010 California Institute of Technology. Government sponsorship acknowledged.

2 Outline Proposed Mission Overview Instruments, Electra, and Ka band Mission Phases Key FSW Requirements Common To All Instruments FSW Inheritance Interface Block Diagram Communication Protocols Cmd/Tlm Database integration Fault Protection Data Volume Constraints Data Reduction JL-2

3 Proposed Mission Overview The proposed ExoMars/Trace Gas Orbiter would be a new and exciting joint NASA/ESA mission to Mars to be launched in The mission elements would include a science orbiter and a demonstration lander. ESA is responsible for providing the orbiter bus and lander while JPL is to provide four out of five science instruments and spacecraft telecommunications hardware for Ka band, X/Ka band antenna, and UHF Electra. NASA/JPL would also provide the launch vehicle. ESA has the lead in the overall mission operations. JPL would lead the science operations from the Science, Relay and Aerobraking (SRA) center at JPL. The telecommunications hardware including Ka Band and Electra would be integrated into the orbiter to provide deep space link and relay functionality from ground to both the demonstration lander and potential future landed assets on Mars. JL-3

4 Instrument Suite HiSci (NASA/JPL/UA/BATC) MAGIE (NASA/JPL/MSSS) MATMOS (NASA/JPL/CSA) High Resolution Stereo Color Imager Mars Atmospheric Global Imaging Experiment Mars Atmospheric Trace Molecule Occultation Spectrometer EMCS (NASA/JPL) NOMAD (BIRA-IASB) ExoMars Climate Sounder Nadir and Occultation for Mars Discovery JL-4

5 Electra NASA/JPL would provide two redundant Electra boxes (including FSW) to be used for communication with ground assets. These boxes would be connected to a single UHF antenna provided by ESA. JL-5

6 Ka-Band NASA/JPL to provide: A single m HGA 2 x Ka band TWTAs Antenna pointingmechanism (including FSW) ESA to provide: 2 x X band TWTAs X/Ka band switching X/Ka band transponders JL-6

7 Mission Phases Baselined to launch out of Cape Canaveral in January, 2016 Cruise (10 months in 2016) EDL Demonstration Module experiment upon arrival (8 days in 2016) Use Electra for communication with EDM Aerobraking (6 months in ) Nominal orbiter science operations (2 years; ) 74 degree inclination Observe during dayandnightand night Nadir and limb/sun occultation observation modes Relay Support for future orbiters (through 2022) JL-7

8 Key FSW Requirements Common To All Instruments Software simulation model Patch capabilities Event reports under anomalous conditions FSW parameter modification Distinct areas of memory for code, constants, and variable parameters. Fault protection (intrinsic as well as support of system FP) Support for safe and nominal modes 1553 (Cmd andrt Tlm) and Spacewire (Science & SSOH) interfaces JL-8

9 FSW Inheritance EM/TGO Heritage Heritage % FSW Instrument t Instruments t Missioni Inherited EMCS MCS MRO > 85% HiSci OLI LANDSAT > 50% MAGIE MARCI, Mastcam, MAHLI, MARDI MRO, MSL > 80% Electra N/A MAVEN > 90% JL-9

10 Interface Block Science Instruments Diagram MATMOS (Self-contained FSW) NOMAD (Self-contained FSW) X/Ka Band (Self-contained FSW) 1553 C/D X/Ka RF Interface Legend NASA Provided Spacewire (100 Mbps) BIRA Provided EMCS (Self-contained FSW) 1553 A (500 Kbps) 1553 B Orbiter Bus Module (ESA orbiter bus FSW only. No instrument, Ka band, or Electra FSW) ESA Provided 1553 bus Spacewire MAGIE (Self-contained FSW) HiSci (Self-contained FSW) LVDS (10 Mbps) LVDS (12 Mbps) Electra Electra (x2) (2) (Self-contained FSW) Note: All interfaces are preliminary and subject to change LVDS RF Interface JL-10

11 Communication Protocols MIL STD 1553B Instrument/Electra commanding Instrument/Electra time sync Instrument/Electra R/T Telemetry Ka band gimbal control commanding ECSS E ST 50 12C (Spacewire) Instrument science data Instrument SSOH data Science Protocol(SP)/CCSDS File Delivery Protocol (CFDP) Electra forward and return link relay data JL-11

12 Cmd/Tlm Database Integration The s/c CTDB is owned by ESA. Both thnasa and non NASA instrument t teams to provide inputs to JPL, which would, in turn, provide integrated t dctdb inputs to ESA. The format of these inputs has not yet been determined. JL-12

13 Fault Protection Multi tiered FP design approach. Instruments t to handle local levents. Real time telemetry provided to orbiter bus FSW to handle system level FP and mode changes. JL-13

14 Data Volume Constraints Instrument % Allocation of 8 Gbit/day Avg. (Science Data only) HiSci 36% Instrument Data Volume Usage (Gbits/day) MATMOS 24% NOMAD 16% MAGIE 4% EMCS 2% * Unused portion is based on an 8Gb/day allocation to all instruments Total 82% JL-14

15 Data Reduction In order to meet the tight data volume requirements, instruments would employ stateof the art compression and/or on board data reduction techniques such as binning, averaging, and on board science data processing. JL-15

16 MATMOS Data Reduction Raw interferograms are converted to spectra on orbit via L0 L1B processing on 2 x RAD 750s. A 100:11 reduction in data is achievable by a combination i of the following: On board processing 2:1 lossless compression 12 bit spectral resolution Averaging Intermediate products (L0, L1A) are discarded Removal of non useful spectral regions Raw data is occasionally downlinked to ground to verify on board processing algorithms. JL-16

17 The proposed ExoMars/Trace Gas Orbiter promises to be an exciting mission. The detection of methane and other trace gases is an essential next step in the search for life on Mars. The imaging instruments would continue essential mapping that would otherwise not exist when MRO and other orbiters reach their EOL. The on board Electra & Ka band electronics would provide a basis for communications with future NASA/ESA Mars ground assets. Pre-decisional - for - for planning and discussion purposes purposes only. only. This document This document has been has been reviewed and and determined not to to contain export export controlled controlled technical technical data. data. JL-17

18 Contact Info/Links Jason LaPointe ExoMars/TGO Project tsoftware Systems Engineer Jet Propulsion Laboratory Pasadena, CA Further Reading: ESA Web Site: JL-18

19 Image Credits Title page, Mars horizon: NASA/JPL Caltech Title page, orbiter: artist s concept, ESA Mission i Overview, orbiter: ESA Instrument Suite MAGIE instrument: MSSS HiSCIi instrument: t UA, BATC NOMAD instrument: BIRA IASB MATMOS/EMCS instruments: NASA/JPL Caltech Electra: NASA/JPL Caltech Clt Ka band: NASA/JPL Caltech Conclusions, background: artist s concept, ESA JL-19