Скачать презентацию Flight Operations of the Swarm Constellation Frank-Jürgen Diekmann Скачать презентацию Flight Operations of the Swarm Constellation Frank-Jürgen Diekmann

d1fa392fef3ec89b4d3e79bf4cee1b03.ppt

  • Количество слайдов: 16

Flight Operations of the Swarm Constellation Frank-Jürgen Diekmann for the SWARM Flight Control Team Flight Operations of the Swarm Constellation Frank-Jürgen Diekmann for the SWARM Flight Control Team Earth Observation Missions Division ESA/ESOC 19/06/2014

Mission Phases Supported By Swarm FOS 1. Development Phases o Ground Segment definition, development Mission Phases Supported By Swarm FOS 1. Development Phases o Ground Segment definition, development & procurement, support to spacecraft planning o Testing & validation, tracking campaigns o Team training 2. LEOP : Launch and Early Orbit Phase o Take over control after separation of 3 satellites in parallel o Switch each satellite into a fully operational configuration o Functional check-out 3. Commissioning o Platform and payload commissioning, calibration and validation o Orbit injection phase and acquisition of final constellation o Ground segment commissioning 4. Routine o Continuous monitoring & control, anomaly handling o Orbit / Attitude and Constellation maintenance o Ground Segment maintenance and evolution 5. End-of-Life o Passivation o Deorbiting (passive re-entry)

Flight Operations Segment (FOS) High Level Overview FOS Subsystems: Kiruna / Svalbard / Troll Flight Operations Segment (FOS) High Level Overview FOS Subsystems: Kiruna / Svalbard / Troll / Perth (LEOP) Svalbard Realtime and recorded telemetry Commanding/TC - External Server (sftp) and EDDS Simulator Flight Dynamics System FOCC (ESOC) EDDS External File Server Satellite TM/TC Database Mission Planning System Support Teams Industry Support - Flight Dynamics System - Satellite TM/TC Database Communication Network Mission Control System PLSO - Mission Control System - Simulator Recorded telemetry to PDGS - Ground Stations and Communication Network PDGS : Payload Data Ground Segment, ESRIN PLSO : Post Launch Support Office, ESTEC Mission Prime Scientific Community To SLR

Mission Control System and Mission Planning • • Multi-domain capabilities of the Mission Control Mission Control System and Mission Planning • • Multi-domain capabilities of the Mission Control System (MCS) Manual commanding (TC) capabilities (to several Swarm satellites in parallel during LEOP) Processing of real-time telemetry (TM) (VC-0 and VC-1) Processing of mass memory retrieved telemetry (VC-4) Monitoring and retrieval functions from real time servers Interface with Flight Dynamics System Interfaces to ground stations via ground comms network for transmission of TM, TC, tracking data, etc. Mission Planning and related interfaces, main tasks : o Command generation for station handling (automated pass operations) o Command generation for onboard data handling (time tagged commands in MTL) • • • Data of the full mission will be archived on the Swarm prime and backup servers. Retrieval and provision of telemetry from long term archive Operated by small Flight Control Team

Mission Data Distribution • Recorded telemetry (TM) files are retrieved from the ground stations Mission Data Distribution • Recorded telemetry (TM) files are retrieved from the ground stations by the Generic File Transfer System (GFTS) and transferred to the prime and backup servers at ESOC. • At Kiruna and Svalbard stations two sets of files are created : one for the FOS (has a special header) and one with files containing frames only for the PDGS • At ESOC the telemetry files are automatically replayed (a software tool runs permanently to populate the FOS control system with VC 2 and VC 4 data) • Telemetry retrieval based on some new ESOC infrastructure systems : o o • EDDS provides a user friendly client (EDDS MMI) to access standard data product files containing o o o • EDDS (EGOS Data Distribution System) server per domain DARC (TM parameter) and PARC (packet) archives Telemetry Packets (Housekeeping and Science TM) Telemetry Parameters (Housekeeping and partially Science TM) Telecommand History FOS is distributing 193 files per day to external recipients (number of users and files unusual high for a FOS)

Mission Database And Flight Procedures • The Mission Database is the backbone for all Mission Database And Flight Procedures • The Mission Database is the backbone for all operational activities. o o o o • Telecommands Sequences Alpha Numeric Displays Graphic Displays Packets Telemetry Parameters (total) Parameters (in Packets) Out Of Limit Checks 2966 2786 629 228 2185 47409 29398 1675 All spacecraft commanding is based on Flight Operations Procedures (FOP) o 617 Nominal Procedures o 116 Contingency Procedures o 32 specific LEOP Procedures and Timelines • • All procedures were validated and tested on the simulator Procedures are constantly reviewed and updated, when necessary

 • Kiruna, Svalbard, Troll, ESRANGE : TC and ranging, TM low and high • Kiruna, Svalbard, Troll, ESRANGE : TC and ranging, TM low and high bit rate • Provision of VC-4 TM files to the PDGS from Kiruna and Svalbard • Interface with the Mission Control Center for 2 passes per day and per satellite • Interface with Flight Dynamics for ranging data provision and reception of antenna pointing elements 15 m antenna, ESA station in Kiruna, Sweden ESA UNCLASSIFIED – For Official Use

Swarm Ground Station Passes • Usage of the ground stations until May 2014, in Swarm Ground Station Passes • Usage of the ground stations until May 2014, in number of Swarm passes: • Number of passes per day for routine phase : 2 passes per satellite is working very well and will be continued until further notice. Only 5 passes failed completely until now (0. 3%). •

Flight Dynamics System (FDS) Support Ø The three Swarm satellites are in near circular, Flight Dynamics System (FDS) Support Ø The three Swarm satellites are in near circular, nun-Sun synchronous, near polar inclination orbits, with Swarm-A and Swarm-C flying in constellation. Ø Swarm orbit maintenance is provided by the ESOC FDS Team. FDS consists of 4 main sub-systems and an independent test and validation function: • Attitude monitoring o • Orbit Determination o • Calculation of manoeuvres required to meet orbital targets based on latest orbit determination; minimization of fuel usage, respecting constraints. Command Generation o • Determination and prediction of orbit, based on tracking data in LEOP and GPSR data extracted from TM thereafter. Generation of orbital products. Manoeuvre Optimization o • AOCS TM monitoring, performance of sensors and actuators, inter-comparison of STRs and STR and CESS/FGM, fuel bookkeeping, GPSR data extraction from TM Generation of command parameters to be passed to FCT; generation of reports and mission planning inputs. Test and Validation o o Software and System validation operational internal and external interface validation

Commissioning : Orbit Injection Phase 10 Manoeuvre batches needed for orbit acquisition phase (1 Commissioning : Orbit Injection Phase 10 Manoeuvre batches needed for orbit acquisition phase (1 -3 days each) Injection Orbit : 6880 km (semi-major axis at ascending node (ANX)) Current altitudes (semi-major axis at ANX) • • • Swarm-A : 6849 km (h=468 km) Swarm-B : 6897 km (h=516 km) Swarm-C : 6849 km (h=468 km) (eccentricity : 0. 0004) Current inclinations: • • • Swarm-A : 87. 35˚ Swarm-B : 87. 75˚ Swarm-C : 87. 35˚

Orbital Parameters of Swarm-A and -C Current Right Ascension of Ascending Node, Difference SWA-SWC Orbital Parameters of Swarm-A and -C Current Right Ascension of Ascending Node, Difference SWA-SWC : ca. 1. 4º Current Semi Major Axis, Difference SWA-SWC

Swarm-A and Swarm-C Separation Maintenance Results of a recent manoeuvre modelling: Swarm-A orbit lowering Swarm-A and Swarm-C Separation Maintenance Results of a recent manoeuvre modelling: Swarm-A orbit lowering by 13 m and 7. 5 mm along-track thruster firing, Results for different drag coefficients Manoeuvre actually executed on 12. 06. 14 : Expected Swarm-A orbit lowering by 14 m and 8 mm/sec along -track thruster firing (37 sec)

Fuel Consumption Since Launch • • • Manoeuvre performance nominal, marginally less efficient than Fuel Consumption Since Launch • • • Manoeuvre performance nominal, marginally less efficient than expected (slightly more fuel consumed on attitude control during the burns, ~15% vs ~13% expectation) Consumption mostly in-line with the Mission Analysis assumption Fuel remaining after Orbit Acquisition (status : 1. June 2014) : o o o • SW-A from 105. 5 kg, 66. 5 kg remaining after the OIP (39. 0 kg used) SW-B from 105. 2 kg, 67. 1 kg remaining after the OIP (38. 1 kg used) SW-C from 102. 8 kg, 64. 2 kg remaining after the OIP (38. 6 kg used) This is less than what was assumed for pre-launch fuel budget : SWARM Fuel Load Mission Phases: Swarm FM 1 Swarm FM 2 Swarm FM 3 Attitude Acquisition 0. 32 Orbit Acquisition 50. 93 62. 00 Orbit Maintenance AOCS Propellant Margin Residuals and Leakage 13. 13 18. 04 21. 17 2. 40 0. 76 19. 34 21. 17 2. 40 Total Fuel Loaded 106 106

Swarm-A and Swarm-C Orbit Evolution Swarm-A and Swarm-C Orbit Evolution

Space Debris Office Support • • During all Swarm mission phases the ESOC Space Space Debris Office Support • • During all Swarm mission phases the ESOC Space Debris Office provides in-orbit collision warnings to the Swarm FCT. Assumed, the orbits of the debris and target objects are known with sufficient accuracy, then for initial assessments the information provided by the USSTRATCOM catalogue is sufficient to predict all close fly-bys (conjunctions) of a target satellite with any of the catalogued objects. The provided service also covers processing of externally provided information, such as Close Approach Warnings and Conjunction Summary Messages from the US Joint Space Command (JSp. OC). The collision risk is determined as a function of the object sizes, the predicted miss distance, the fly-by geometry and the orbit uncertainties of the two objects involved. If a chaser object is predicted to approach closer than a predefined limit or exceeds a risk threshold, a warning email is distributed. In a meeting with the involved teams it is then decided, whether to execute a debris avoidance manoeuvre. A collision avoidance manoeuvre might have a non negligible impact in the fuel budget and mission lifetime. Up to now, several collision warnings for Swarm have been received, but no manoeuvre needed to be scheduled yet.

Outlook • The team is well experienced with the overall mission. Crosstraining in various Outlook • The team is well experienced with the overall mission. Crosstraining in various areas has already started to maintain a high degree of proficiency and competence. • Future in-orbit subsystem tests will be supported to further improve the mission performance. • The constellation of the lower satellite pair will be maintained in a way to minimize fuel consumption • Further tests and procedure optimizations are under discussion to better handle on-board events like SEU/SEFI, data gaps, etc. • Following successful LEOP and Commissioning phases, we are looking forward to a long and hopefully trouble-free routine phase.