Final Version

Micro-Arcsecond Imaging Mission, Pathfinder (MAXIM-PF)

Mission Operations

Tim RykowskiJeffrey Hosler

May 13-17, 2002

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Final Version

Mission/Science OperationsTopics

Functional Architecture/Operations Concept Driving Requirements and Assumptions Technologies Required Staffing Approach Costs Issues and Concerns Additional Trades to Consider

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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MAXIM-PF Ground SystemFunctional architecture

Mission Ops Center(@ GSFC)Space-GND IP protocolRT health/safety processingCommandingTrendingMission schedulingInstrument data handling

TBD Science Data Processing Facility

TLM @ 5 Mbps

DSN @Goldstone

MAXIM-PFCMDs @

5 Kbps

TLM, Eng/HK

CMDs

Science Data Products

Instrument CMDs,coordination

TBD Instrument Science Team

Detector

Hub and FF Eng/HK

Free Flyers (6)

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Mission/Science OperationsOperations Concept

All Space-Ground Communications for entire Constellation is provided by Detector spacecraft Detector spacecraft collects all ground commands, and distributes to the

entire constellation Detector spacecraft to Optical Hub to Free-fliers via crosslinks

Housekeeping data from entire constellation relayed to Detector spacecraft, where it is delivered to the ground. Free-fliers to Optical Hub to Detector spacecraft via crosslinks

Formation control data exchanged via crosslinks but not downlinked to ground

Internet Protocol used for communications Provides easy means to identify/address each “node” in constellation Simplifies communications management/solid state recorder

management Minimal ground commanding is envisioned

Formation control is an on-board capability using crosslinks – no ground involvement

Observation targets are well-planned and determined in advance – no targets of opportunity envisioned.

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Mission/Science OperationsDriving Requirements and Assumptions

(1)

Data rates: ≈ 50 Kbps aggregate for entire constellation (includes engineering/house-keeping, and overhead for IP protocol) Detector spacecraft

10 kbps science 4 kbps Eng/HK

Optical Hub/Free Flyers (6) 4 kbps Eng/HK for each spacecraft

Data Latency Requirements: No driving requirements for mission (assuming 24 hour Level

Zero product delivery) Level 0 Products: Instrument/HK data files stored on-

board detector spacecraft and delivered to MOC using IP protocol

Data Recovery: Assume 98% recovery requirement (end-to-end)

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Final Version

Mission/Science OperationsDriving Requirements and Assumptions

(2)

Space-Ground contact profile: One contact daily @ DSN Goldstone @ 5 Mbps.

Planning and Scheduling requirements: No target of opportunity requirements – observation targets/sequencing of observations known well in advance.

MOC functionality: MOC provides “standard” set of functionality to support Mission

Operations (e.g., S/C and instrument commanding,mission planning/scheduling, RT TLM monitoring, offline analysis)

MOC provides IP protocol processing in support of space-ground communications. File assembly, data acknowledgements

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Mission/Science OperationsTechnologies Required

Virtually all Mission Operations functionality can be satisfied with currently available technology Software packages exist today to provide the following required

functions (will need to be modified for mission-specific considerations) Command/Control Planning/Scheduling Spacecraft Performance Assessment Light-out (unstaffed) operations

Use of space-ground IP protocol not current state of practice, but is planned to be implemented for NASA missions (SDO,GPM) well in advance of MAXIM-PF No major technology risks – significant prototyping work has

been conducted to date. Little or no technology development is envisioned to

accomplish the pathfinder mission

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Mission/Science OperationsStaffing Approach

Nominal Mission Operations can be accomplished using a weekday, day-shift (8x5) staffing approach Minimal space-ground contacts

No driving latency requirements Modest data rates

Formation flying/control performed autonomously on-board Minimal planning/scheduling requirements

Operations Team is “on-call” to respond to anomalies/spacecraft emergencies during off-shifts Appropriate technologies (remote user access, paging systems)

used to ensure time-critical response.

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Mission/Science OperationsCosts

($K, FY 2002 $)

Pre-launch Post-launch: 4/5 yrs of ops

TOTAL (4/5 yrs)

Development $3.9 M $3.9 M

Pre-launch testing/ops

$1.7 M $1.7 M

Post-launch Operations

$5.6 M/$6.7 M $5.6 M/$6.7 M

Maintenance /Consumables

$1.2 M/$1.5 M $1.2 M/$1.5 M

Communications links

negligible negligible negligible

TOTAL $5.6 M $6.8M/$8.2 M $12.4/$13.8 M

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Mission/Science Operations Cost Basis of Estimate

Development Cost Assumptions MOC located at GSFC

Costs do not assume reuse of any existing hardware or software For MOC real-time and data processing support, assuming 3 logical

strings Prime, Backup, and Dev/Test support Provides required automation functionality and necessary RMA

Mission-specific software development labor included. Communications Link Cost Assumptions

Assume JPL Goldstone delivers data electronically to GSFC at no cost. Operations Staffing Cost Assumptions

Size of operations staff = ≈9 FTE (3 FTE larger than typical 8x5 operations -- additional staff required to perform performance assessment for 8 total spacecraft)

Ops staff costs begin around L-30 months to support pre-launch activities

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Mission/Science Operations Issues and Concerns

Current operations concept requires very high reliability communications links between: Detector spacecraft and Ground Optical Hub and Detector

Failure of either link would be catastrophic to mission

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center Mission Operations

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Mission/Science OperationsAdditional Trades to Consider

For Full MAXIM configuration, should consider the following trades: Automation of Spacecraft Fault Detection, Isolation, and

Recovery (either on-board spacecraft, or in ground system) (+) Potential reduction in ops staffing levels – less engineers needed

to assess spacecraft performance, identify trends (-) Additional development costs for ground system/Flight

Software/C&DH Alternative architectures to provide increased communications

between constellation elements