Payload Operations in Quiet Cruise: An Interplanetary Missions Dilemna

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Payload Operations in Quiet Cruise An
Interplanetary Missions Dilemna
European Space Agency - European Space Operations
Centre

• P. Ferri, E. Montagnon, A. Hubault

SpaceOps 2006 - Roma
June 2006
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Outline

• The Rosetta Mission Baseline
• The Rosetta In-flight Experience
• Anomaly Management
• Science Operations
• Payload Operations Replanning
• Lessons Learned
• Conclusions

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The Rosetta Mission Baseline

• 3 months Instrument Commissioning near-Earth
• 14 Checkout slots every 6 months
• Passive Checkouts
• Active Checkouts
• Scientific operations around mission events

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In-flight Experience Anomaly Management
CVP1 (3)
CVP2 (11)
Post-CVP 2005 (3)
19 extra Anomaly Management Slots in 2005/2006
Post-CVP End 2004 (7)
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In-flight ExperienceScience Requests

• 5 unplanned comet observation campaigns since
  launch (Linear, Machholz, Tempel-1, Catalina,
  Honda)

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In-flight ExperiencePayload Operations
Replanning

• Lack of detailed planning pre-launch due to
  extreme pressure of fixed launch date
• Large replanning effort spent post-launch on the
  payload operations slots
• Main reasons
• Thermal Constraints
• Signal Propagation Delay
• Celestial Objects Geometry

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Lessons Learned (1)

• Keep the Spacecraft on a Low Resource Level
• Most of the extra slots scheduled for anomaly
  management
• 7 out of 40 anomalies discovered during extra
  slots
• Keep payload operations to a minimum
• The only way is a spacecraft mode preventing
  payload operations

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Lessons Learned (2)

• Weigh the Added-value of Science Requests
• Added-value of request for mission
• Impact on on-board resources
• Impact on ground resources
• Impact on mission plan
• -gt Science operations are important for the
  mission, so do not reject unplanned science a
  priori

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Lessons Learned (3)

• Improve the Quality of the Long-term Planning
• Collect payload requirements early
• Take into account geometrical constraints in
  definition of payload slots
• Define criteria for assigning operations to
  pre-defined slots

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Lessons Learned (4)

• Separate Anomaly Management from Normal
  Operations
• Anomalies are unavoidable
• Define dedicated Anomaly Management slots away
  from science operations slots
• Consider commissioning in two parts
• Baseline science in cruise
• -gt Cruise operations allow early detection and
  resolution of anomalies and increase robustness
  of operations tools and procedures

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Conclusions

• The Rosetta Mission Baseline was assuming a quiet
  cruise in terms of payload operations
• However in-flight experience shows that payload
  operations cannot be avoided if the spacecraft is
  in active mode
• Cruise payload operations have benefits in terms
  of secondary science, but also for gaining
  experience and early anomaly resolution
• Generic rules can be derived to minimise impact,
  that will be applied to upcoming Rosetta mission
  phases and future ESA Interplanetary Missions,
  such as BepiColombo