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5. Space Technology. “Tomorrow’s Technology Today”. GSFC. Section 19.0 Combined Ground System. Irene Bibyk Ground System Manager. ST5 PDR June 19-20, 2001. Agenda. Introduction Mission Operation Center Integration Ground Data System - ASIST Ground Station/Network Flight Dynamics
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5 Space Technology “Tomorrow’s Technology Today” GSFC Section 19.0 Combined Ground System Irene Bibyk Ground System Manager ST5 PDR June 19-20, 2001
Agenda • Introduction • Mission Operation Center Integration • Ground Data System - ASIST • Ground Station/Network • Flight Dynamics • ST5 Technology Demonstration - SatTrack • Risk Mitigation
5 Space Technology “Tomorrow’s Technology Today” GSFC Introduction ST5 PDR June 19-20, 2001 19-3
Combined Ground System & Operations Launch Dress Rehearsal SIM GROUP 1 SIM GROUP 2 SIM GROUP 3 Readiness Test-9 & 10 Readiness Test-7& 8 Readiness TeST5 Readiness Test-4 Readiness Test-1 Readiness Test-6 Readiness Test-3 Readiness Test-2 Tech. Aliveness Test-1 . Test-30 . Test-2 . Test-1 . Test-4 Tech. Aliveness Test-3 Tech. Aliveness Test-2 Network Test-1 Network Test-3 Network Test-2 Compat Launch Compat Compat Compat Msn Msn Msn Msn Msn Msn Msn Msn 3/02 6/02 9/02 9/01 3/03 6/01 9/03 12/01 6/03 12/02 12/15/03 MRR MOR CDR FOR PDR Draft FPD Final FPD Final DMR Final OCD Draft FOP Fin FOP Review OCD
Documentation • Operations Concept Document - Preliminary complete • Flight Operations Plan • Flight Procedures Document • Launch & Early Orbit Handbook • Detailed Mission Requirements Document - Preliminary complete • ASIST ICD - Heritage from MAP & EO-1 • FD ICD • SatTrack Requirements Document - Complete • SatTrack Statement of Work - Complete • SatTrack ICD • Ground Station Requirements Document - Complete • Ground Station Statement of Work - Preliminary complete • Ground Station RF ICD
5 Space Technology “Tomorrow’s Technology Today” GSFC Mission Operation Center Integration 19-7 ST5 PDR June 19-20, 2001
Requirements/Approach • The GDS shall provide interface support for the Autonomous Network Scheduling and Orbit Determination S/W(MRD 30401000) • ASIST shall interface with SatTrack via a TCP/IP socket for ascii file transfer • The mission shall be capable of supporting “lights out” operations(MRD 30500000) • Standard GSFC automation approach with ASIST and SERS, except for the addition of the ST5 tech demo of SatTrack • Approach • In-house mission operations center will be co-located with one of the existing MOCs in Bldg. 14, such as MAP, TRACE or EO-1 • Heritage system in an existing facility will reduce risk and save money by taking advantage of security perimeter, redundant utilities and communications. (Note: FOT and systems are not planned to be shared) • FOT training and control center checkout to occur during I&T
Data Flow Diagram GPS - Ranging - Data transfer - Science event GSFC-site ST5 Experimenter Operations Center ST5 Mission Operations Center - Exp Planning - Instrument Eval - Experiment Data Processing EARTH RealTime System Offline System RTADS (Nominal) RTADS (L&EO) -Near RealTime Attitude Determination for Launch & Early Orbit - Maneuver Planning Magnetometer (ASIST Assoc) - Uplink/Downlink on X-Band - Two way Doppler Tracking Attitude Telemetry MMFD/Nom Ops -Bldg 28 - Orbit Predict JPL CCNT Ground System Commands - Sun sensor - Magnetometer - Attitude Ground Station Recorder Data/VC# - Predicted Orbit NISN ASIST - Telemetry Monitoring - Command Load & Uplink - Data Storage - Limit Checking - Events Monitor - Automated STOL Proc Exec Real time Data/VC# Mission Planning System Planning Aids SatTrack/Tech Demo - Automated Ground Station Scheduling and - Orbit Determination Commands/VC# Data Auto-STOL Proc/Status NASA Integrated Services Network Orbit Pred Tracking Tracking Orbit Skytel Paging Service VMOC Data Server PAGE FOT
Mission Readiness Test Flow Three Series of Tests (FlatSat, S/C No.1, Constellation) Jan’03 - Apr’03 May’03 - Jul’03 S/C No.2 & No.3 Integration & Test S/C No.2 & No.3 Environmental Tests Aug’02 - Oct’02 Nov’02 - Mar’03 S/C No.1 Integration & Test S/C No.1 Enviromental Tests Apr’03 - Jun’03 Nov’02 - Mar’03 May’02 - Oct’02 Constellation Test Series - RF Compatibility Tests (No.2&No.3 - Pre-TV) - Technology Aliveness Test No.3 - Comprehensive Timing Test No.3 - FINAL End - to - End Test (Cmd & Tlm Test) S/C No.1 Test Series - Basic Timing Test No.2 Tech Aliveness Test No.2 - PTP Validation Test - RF Compatibility Test(Pre-TV) - Basic Timing Test No.2 (in TV) - RF Compatibility Test (Post-TV) FlatSat Test Series - Basic Timing Test -MOC Set-up Test - Tlm & Cmd Processing Test - Tech Data Validation Test -Cmd Management Test Apr’03 - Jun’03 Ground Segment Test Series with FlatSat and/or S/C No.1 - TT&C Ground Station Tests Mission Planning & Scheduling Tests - SatTrack Lights-out Test Comprehensive Ground Station Test - Mission Science Data Processing Test Feb’03 Aug’02 Jul’03 Simulation No.2 S/C 1 (Env) Simulation No.1 (FlatSat) Simulation No.3 S/C 2 & 3 (Env)
Status • High level integrated schedule with I&T developed • H/W and S/W purchases (ASIST/FEDS) • I&T, Ops, subsystem staffing for I&T, Mission Readiness Tests and Mission Operations in work
5 Space Technology “Tomorrow’s Technology Today” GSFC Ground Data System-ASIST 19-12 ST5 PDR June 19-20, 2001
Requirements • The Mission shall validate the ability to take measurements and to handle the downlink and ground data processing of multiple data streams from multiple S/C (MRD 20300000) • New ASIST capability where the FEDS will contain multiple ingest cards and data streams will be sorted by S/C ID • Existing data interface protocols will be used with SERS, FD, MPSS, and new technologies (SatTrack and CCNT) • The facility shall have the ability to connect with the vehicle(s) at both baseband (i.e. Hard-Line) and RF (MRD10303080 - supporting) • Heritage connection where the FEDS shall have the ability to connect to the vehicles during I&T • CCSDS recommendations shall apply to space/ground com channels and to basic space/ground services provided to instruments by the S/C (MRD 10303050) • CCSDS applications are heritage systems
Requirements/Approach • Time correlation between the S/C clock & Coordinated Universal Time (UTC) shall be known to within 5 msec (3 sigma) (MRD 20500000 - supporting) • Heritage from EO-1 for Return Data Delay (RDD) time correlation • Ground station will append the time each VC0 CADU was received at the ground station to the internet protocol data unit (IPDU) header and the FEDS will read both S/C time and ground station time tag to determine S/C to UTC time difference • Approach: Heritage systems from IMAGE, EO-1 and MAP; ST5 FSW re-using MAP FSW; ST5 C&DH re-using MAP processor
S/C 1 S/C 2 C & DH HDS S/C 3 I&T and Operations Command & Telemetry Flows ASIST Science Workstations I & T Only CCNT Workstations S/C Data System Bit Sync I & T GSE ASIST Primary Workstation ASIST Associate Workstations S-Band Rcvr X- to S- Down Converter S/C Test Connection Data CLK I/F Box Diplexer X-Band Xponder RF PCI Serial I/O FEDS TSS2000 Modulator BPSK ACB2 S- to X- Up Converter Packet Distribution System R/T Buffer (S/W) Frame Sync (S/W) (CRC, RS) Cmd Processor Gnd Stat I/F NISN Ground Station Time Code Card Digital History Data Storage (DHDS) TCPIP Ops Only
Status • ASIST Workstation deliveries to FSW and GNC (for HDS) completed • FEDS (Front End Data System) in development for C&DH • Timing card will be included • FEDS and ASIST deliveries to FlatSat and FSW in first quarter FY02 • Testing multiple ingest cards in FEDS • ASIST Build 9.1 (some updates with multiple data streams) • Working data management and verification of crosslink data from CCNT
5 Space Technology “Tomorrow’s Technology Today” GSFC Ground Station/Network 19-17 ST5 PDR June 19-20, 2001
Requirements • The ground segment shall provide one 20-minute contact window per S/C every orbit below 5 Re altitude (MRD 10801000) • For nominal operations, ground stations being required to provide 30 minutes of visibility for simultaneous data command, telemetry, and tracking, • Extra time added for link acquisition and margin • Stations must be compatible with new ST5 technology transponder; sweep, acquire and lock as listed in the ground station requirements specification • Data recovery goal for ground station is 90% (space to ground), in support of technology and science validation requirements minimum of 70% of on-orbit generated data constellation in total shall be received by the ground(MRD 10800000 - supporting)
Requirements • The ground station network shall provide X-band command uplink capability, in at least 1 station(MRD 10104041) • 2 stations are highly desirable for more coverage with orbit uncertainties and as a back-up station • Nominal operations may be capable to work with a less-than-once-per-orbit uplink command window (i.e., every 2nd/3rd pass) • Time correlation (update S/C clock), tracking and operational scenarios will determine the uplink contact frequency • The system uplink data rate shall be 1 Kbps.(MRD 10303061 - supporting) • New X-band equipment required, but data rate is not challenging
Requirements • The S/C shall have 2, ground selectable, downlink data rates: 1 Kbps (2 Ksps) and 100 Kbps (200 Ksps) (MRD 10303063 - supporting) • The S/C shall be capable of supporting the high rate downlink to a communications range of 5 Re.(MRD 10303065 - supporting) • The S/C shall be able to support the low data rate downlink at any point in the orbit(MRD 10303066 - supporting) • The ground station shall be capable of performing Doppler tracking in support of orbit determination (MRD 10301020) • The system radiometric Doppler tracking accuracy shall be sufficient to support ground antenna pointing at distances of 2 to 5 Re. (MRD 10301011 - supporting) • Ground station oscillator must be stable enough to support • The system shall be capable of supporting the mission using only one-way Doppler measurements from the S/C (10301012 - supporting) • Transponder oscillator will determine performance
Orbit Scenario Nominal Operations Total contact time required per orbit: ~90 mins (1.5 hrs) - Range limited between 2 - 5 Re for simultaneous: - Recorder downlink at 100 kbps (range limiting factor) - Real-time downlink at 1 kbps - Command uplink at 1 kbps - Two-way Doppler tracking Apogee @ ~5:15 5 Re @ ~7:08 L&EO: No time specs, need schedule flexibility Any Point in Orbit for simultaneous: - Real-time downlink at 1 kbps - Command uplink at 1 kbps - Two-way Doppler tracking 2hrs&24mins 144mins 5 Re @ ~3:22 2 Re @ ~9:32 Perigee @ ~10:31 2 Re @ ~0:58 Notes (for s/c illustration): All attitude and orientations not to scale S/C and antenna beam not to scale S/C distances not to scale Perigee @ ~0:00
Orbit Analysis - Preliminary Assumptions: Apogee at ascending node, perigee at descending node, Epoch December, Antenna spinning 86-40ºoff boresight, inclination of 25 º, eclipse not included L&EO Req: Flexibility to ensure H&S C/O----> Nominal Operations Req: 180 mins/day ---->
Requirements • Ground station-received AGC levels in addition to auto-tracking antenna angles shall be provided (MRD 10104024) • Ground stations to provide data each pass in support of transponder performance validation • Information is currently available today - no changes • Time correlation between the S/C clock and UTC shall be known to within 5 msec (3 sigma) (MRD 20500000 - supporting) • Telemetry received by the ground network shall be time tagged to an accuracy of at least 1 msec (3 sigma) of UTC (20504000) • With today’s GPS H/W at the ground stations, this can be accomplished easily
Approach • Modify an existing station network to support ST5 • Many existing stations have S-band transmitter with an X-band receiver and the receiver is compatible with ST5 transponder • DSN only station network with X-band transmitter and receiver (not planning to use DSN for ST5 Operations)
Status • Requirements document (ST5-495-052) completed • SOW (ST5-495-064) and Task Order in process • Preliminary visibility analysis completed • Major Milestones • Ground station (commercial or government) on board - August 2001 • Ground Station ICD - December 2001 • RF Compatibility tests - November 2002 • MRT- Operational Readiness - May 2003
5 Space Technology “Tomorrow’s Technology Today” GSFC Flight Dynamics ST5 PDR June 19-20, 2001 19-26
Approach • Pre-launch-develop and verify tracking method • Pre-launch support for 2-way Doppler tracking requirement definition and verification • Post launch, MMFD located in Bldg 28 (GSFC) is prime for OD support at launch and during nominal mission operations • Orbit determination within 10 km for ground antenna pointing • An 11-m ground antenna at a distance of 2 Re from S/C, orbit position knowledge of 24Km (3 sigma) or a deviation of no more than 8Km (1 sigma) • Maneuver support during launch and early orbit • Attitude and orbit determination • Attitude and orbit product generation • Products required throughout operations
5 Space Technology “Tomorrow’s Technology Today” GSFC Autonomous Network Scheduling and Orbit Determination S/W Requirements 19-28 ST5 PDR June 19-20, 2001
Technology Demonstration • Technology Provider - Bester Tracking Systems, Inc. • Technology Description • Future Ground Operations Automation for Constellations Enabling Technology • S/W tool to perform autonomously • Ground station scheduling and orbit determination • Experience • 1st revision to be used on HESSI • HESSI uses GSFC’s ITOS ground system • Technology Readiness Level => Currently: 4 (SatTrack) => Currently: 2 (New tools) => Phase D: 7 • Ground station schedule conflict resolution • Station view periods, dynamic link margin, S/C emergencies, time constrains • Flight Dynamics Requirements • Includes comprehensive products such as orbit determination, mission planning products, state vectors, real-time graphic & alphanumeric displays
Requirements • The system shall validate the Autonomous Network Scheduling and Orbit Determination S/W (MRD 10108000) • In addition to actual assets for the mission (i.e. 3 S/C and 2 ground stations), a set of virtual assets (i.e. both S/C and ground stations) shall be simulated and supplied to the Autonomous Network Scheduling and Orbit Determination S/W for processing (MRD 10108020) • Flight validation of the Autonomous Network Scheduling and Orbit Determination S/W shall be accomplished through comparison of the generated output with standard orbit determination S/W and manual ground resource scheduling techniques (MRD 10108010) • Anomalous operation of the Autonomous Network Scheduling and Orbit Determination S/W shall not degrade the operation of the S/C (MRD 10108040)
ST5 Mission Operations Scenario of 3 real and 97 virtual satellites
Data Flow for SatTrack Validation Ground Station(s) Multi-Mission Flight Dynamics Tracking Data Orbit Determination Mission Planning Product Generation Schedules Telemetry Commands ASIST/FEDS SatTrack Commanding Telemetry Monitoring Data Storage Automated STOL Procedure Initiation Orbit Determination Mission Planning Product Generation Ground Station Scheduling Status feedback Command Loads Mission Planning / Scheduling System Mission Planning Load Generation Ground Station Scheduling Mission Planning Products
SatTrack S/W Technology • Used for efficient management and Autonomous Operation of a Satellite Constellation • Autonomous scheduling of ground station contacts • Calculate station access based on number of constraints (line-of-sight, geometry, link margin) • Calculate priorities to resolve conflicts based on various input parameters • data volumes, station capability & availability, science requirements, S/C emergencies, operator overrides, etc. • Autonomous Orbit Determination • Derive updated state vectors from angle & range rate measurements • Verify & archive new state vectors • Generate mission planning products with new state vectors
SatTrack Status • Status • Requirements document (ST5-495-046) completed • SOW (ST5-495-045) completed, waiting for proposal • Major Milestones • S/W delivery 1 (Orbit Determination Tool)-July 2002 • S/W delivery 2 (Automated Scheduling Tool)-February 2003 • Mission Readiness Test-April 2003
5 Space Technology “Tomorrow’s Technology Today” GSFC Risk Mitigation ST5 PDR June 19-20, 2001 19-35
Risk Mitigation • Risk: No ground stations are currently compatible with ST5 transponder which lead to uncertainties with costs and schedule for upgrades • Mitigation: CSOC has identified potential vendors with a fixed-price cost estimate • Risk: Actual launch scenario not fully defined resulting in ground system uncertainty • Mitigation: Concerned about ground station visibility to meet requirements for L&EO, tracking, health & safety, and data recovery • Preliminary analysis has identified visibility against typical launch scenario • Risk: Staffing in the timeframe prior & during S/C No.2 & No.3 flow • Mitigation: Relying on subsystem personnel to supplement Mission Operations activities • Relying on an existing GSFC MOC facility with most interfaces for Mission Operations in place