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X-ray Missions Delta: Gratings Redux. Mission Operations Jeffrey Ferrara (original study) 19 – 23 March, 2012 Deborah Knapp ( Redux study) 2 - 4 May 2012. Topics. Mission Operations Summary Ground System Functional Architecture MOC Architecture (typical)
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X-ray Missions Delta:Gratings Redux Mission Operations Jeffrey Ferrara (original study) 19 – 23 March, 2012 Deborah Knapp (Redux study) 2 - 4 May 2012
Topics • Mission Operations Summary • Ground System Functional Architecture • MOC Architecture (typical) • Study Requirements – Mission Operations • Key Customer Requirements • Mission Overview • Mission Timeline • Technology Assessment • Cost Basis of Estimate • Mission Operations Periods • Staffing Periods Used for Costing • Cost Summary • Cost Summary of Gratings Study • Risk/Issues/Concerns • Additional Trades • Acronyms
Mission Operations Summary • Mission Operation Control (MOC): • Provides “standard” set of functional components to support Mission Operations (e.g., S/C commanding, mission planning/scheduling, and RT TLM monitoring, HK trending and analysis). • Provides level zero processing (LZP) • Level 0 Products: Time-ordered, quality annotated data sets produced for each contact • Level 0 products transferred to Science Operations Center (SOC) • Provides voice communications between the MOC & SOC for coordination • Space-Ground contact profile • DSN (34 meter antenna) • TDRSS for launch & early mission operations • Spacecraft data link rates: • DSN • S-band via HGA • 2 kbps command • 8 kbps housekeeping telemetry • S-band via Omni • 1 kbps command • 2 kbps housekeeping telemetry • Ka-band • 10 Mbps science telemetry • TDRSS • 1 kbps command • 1 kbps telemetry • Data Latency Requirements: • 72 hour required • Data Recovery: • Assume 98% recovery requirement (end-to-end) • Orbit Determination via DSN ranging
Ground System Functional Architecture Legend: CMD = Commanding HK = House-Keeping data TLM = Telemetry data Launch & early mission S-band TLM: 1 kbps CMD: 1 kbps Ka-band TLM: 10 Mbps S-band TLM: 8 kbps CMD: 2 kbps Mission Ops Center Mission planning & scheduling Orbit determination/control Network & contact scheduling Commanding S/C monitor/control RT health/safety processing Trending/Analysis Instrument data handling Level 0 product processing Level 0 Data Archive FDF is costed by FDF engineer Science Ops Center Data Processing & Analysis Experiment planning Payload monitoring Costed by customer Voice DSN Prime TLM, HK WSC TLM, HK 1.5 Mbps CMD TLM, HK 1.5 Mbps CMD Basis of cost study is in red
MOC Architecture (typical) Level Zero Processing Attitude Control Flight Dynamics Telemetry & Command Data Front-end System Ground Stations SOC LAN/Message Bus Mission File Server /Archive Anomaly Notification Event Display/ Logging Data Analysis & Trending Mission Planning & Scheduling Email & Internet Access Internet
Key Customer Requirements • Launch date: 6/11/2021 • Mission Life: 3yrs. required, 5 yrs. Desired • Begins after 3 month trip to L2 • SE L2 solar orbit (with ~800,000 x ~500,000 km halo) with no eclipses • Class B mission
Mission Overview • X-ray telescope with 1 instrument, the X-Ray Grating Spectrometer (XGS) [either OP or CAT] • X-ray spectroscopy of selected targets
Mission Overview Launch (L) at T0 Transfer Trajectory Insertion (TTI) at L + 25 to 120 minutes After outgassing Jettison/Open Flight Mirror Assembly Covers, Open Instrument, LV Separation: TTI + 5 minutes Calibrate w/ Celestial Targets then start Science Ops Deploy Solar Arrays & High Gain Antenna ELV Dispersion Corrections at TTI + 24 hours Commence Instrument Aliveness Checks EOM/Disposal: L + 5 years Spacecraft full power on First Mid-Course Correction: TTI + 16 days Commence Observatory Checkout Instrument internal background measurements Second Mid-Course Correction: TTI + 60 days Arrive L2, continue with Science Ops L2 Orbit Insertion (L2OI) TTI + 100 days Launch (L) at T0
Mission Timeline Launch 6/11/2021 L2 Insertion Disposal Prime Mission 36 - 60 months Mission Closeout Cruise 100 days 1 month Instrument Aliveness Checks Nominal Operations
Technology Assessment • Use COTS/GOTS S/W & H/W as basis for MOC implementation • Software packages are available to satisfy MOC required functionality: • ITOS, ASIST, EPOCH 2000, ALTAIR are commercially available today and provide required functionality for Spacecraft Command/Control and Level Zero (LZ) Processing. • Standard PC’s typically with Linux as OS • Low data volume so no special/new technology required • Most required technologies have been at least demonstrated; many in currently operational systems. • Technology Complexity: Low • Technology Readiness Level: 9
Cost Basis of Estimate • Goddard estimated FY2012 Cost Rates used ((FY2010*.024)*.026) • More detail available in the Costs Spreadsheet • Development Cost Assumptions • For MOC planning/scheduling, command load generation/validation and data processing support • Provides three physical h/w strings (primary, backup & test) • Most MOC functions are provided by COTS and/or GOTS software • Minimal new development for Mission unique requirements. • Operations Staffing Cost Assumptions • 8 x 7 operations • 3 yr mission duration begins after 3 month trip to L2 • Communications Link Cost Assumptions • DSN • TDRSS for launch & early mission • Daily downlinks (15 minutes typical) • T1 links between ground elements (1.544 Mbps) • Level 0 Processing • Data available near real time • NOTE: FDF costs are provided by the FDF engineer; SOC costs are provided by the customer
Mission Operations Periods Period 4 (2 months) Period 5 (38-62 months) Preliminary Design Final Design Mission Cleanup Bus & P/L Fab/Assy/Test Payload Primary Ops Bus & P/L I&T System Definition Prep for Launch Launch & Checkout Phase B Start 11/23/18 CDR 11/23/188 PDR 1/19/18 Project Start 3/6/15 Phase C Design Phase B Definition Phase A Preliminary Analysis Period 1 (21.25 months) Mission Definition 10.25 months 24 months 11 months Period 3 (8 months) Period 2 (22 months) Period 6 (3 months) Launch 6/11/2021 Disposal 9/9/246 Phase D-1 Subsystem Development and Spacecraft Integration and Test Funded Schedule Reserve 6 mo. Phase E/F Operations Phase D-2 Launch & Checkout Period 5-1 (1 month) 13 mo 9 mo 3 mo 1 month 42 months 31 months
Cost Summary (ROM) FOR COMPARISON
Risk/Issues/Concerns • Risks • If the ACS fails such that the Solar Array is not shielding the FMA, then only a small attitude change could endanger the FMA (i.e., cause it to point sunward). Under the right circumstances there would be little time for the FOT to react to the situation before FMA failure. Could mitigate with FMA cover for safehold or additional sun shade. • Issues • none • Concerns • none
Additional Trades • Consider reducing staffed hrs. to 8x5 or even less • Consider a multi-mission MOC
Acronyms CDR Critical Design Review CMD Command COTS Commercial Orbital Transportation Services or Commercial Off the Shelf DSN Deep Space Network EOM End of Mission ES L2 Earth – Sun Lagrange Point FT Functional Test GOTS Government Off the Shelf HGA High Gain Antenna HK Housekeeping Kbps Kilo-bits per second LV Launch Vehicle LZP Level Zero Processing Mbps Mega-bits per second MOC Mission Operations Center RT Real Time SA Solar Array S/C Spacecraft SOC Science Operations Center TDRSS Tracking & Data Relay Satellite System TLM Telemetry ITOS, ASIST, EPOCH 2000, ALTAIR are COTS/GOTS available software packages for controlling spacecraft & performing level zero processing