Rosetta Payload Modeling: Resource Management and Conflict Detection

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Rosetta Payload ModelingResource Management
andConflict Detection

• Ruben Solaz
• V.Dhiri, D.Koschny, K.Wirth, P.v.d.Plas,
  M.Sarkarati

Introduction Payload modelling and SW
tools Analysis of past executed operations
(scenarios) Conclusions and open point presented
at the SpaceOps2006 21 Jun 2006
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Introduction (1) Rosetta mission

• Target comet 67P/Churyumov-Gerasimenko
• Launched on Feb 2004
• Gravity assist manoeuvres Earth/Mars swing-bys
• gt18 months ops at comet, starting Aug 2014
• ? monitoring of evolution of cometary
  activity from apheliom to periheliom
• ? deployment of a lander unit for in-situ
  measurements
• Secondary science target asteroids

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Introduction (2) Payload and needs
NEED TO MODEL PAYLOAD
NEED TO PLAN PAYLOAD OPERATIONS
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Introduction (3) parties involved
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SW tool for Payload ops planningExperiment
Planning System (EPS)
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Experiment Definition File (EDF)Highlights

• EDF syntax aims at simplicity
• ASCII, human readable
• Short implementation time (1 2 weeks)
• Easily expandable
• It is not a programming language
• Limited math computations
• Transients/peaks not modelled

MODELLING STEPS
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EDF modelling (1) Modes, Modules and their
power datarate
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EDF modelling (2)telecommands-sequences their
PW and DR
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EDF modelling (3)Constraints and Conflicts

• RSOC planners paramount importance of early
  detection of conflicts
• The EDF of an instrument might contain many (or
  no) constraints.
• EPS executor cross-check all constraints and
  (might) flag a conflict
• Degree of severity is shown (fatal, warning, etc)

• Examples of flagged conflicts
• Intra-instruments-interferences Inst. A signal
  distorted when Inst. B cooler is ON
• Intra-Instrument When Inst. A is in SCAN mode,
  only a subset of sequences allowed
• Geometric Boresight of Inst. A has to be 45 deg.
  from the sun.
• Environmental Inst. A should not be operated
  while S/C doing a wheel off-loading
• Parametric Wrong values passed to a sequence
• Capacity Inst. A memory partition is full.

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EDF modelling (4)spacecraft memory and dumping
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EDF modelling (5)spacecraft memory and dumping
(2)
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EDF modelling (6)Field of Views (FOV)
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Analysis of real scenarios (1)modes timeline
visualization
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Analysis of real scenarios (2)power plots
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Analysis of real scenarios (3)SSMM filling-up
and dumping to ground
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Rosetta Current Payload Status
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Conclusions and open points

• Models currently actively used for planning at
  RSOC
• Models accuracy validated and deemed sufficient
  for all cruise-phase (May 2014)
• Modelling of HK data open.
• Further modelling of interference among
  instruments envisaged after outcome of
  Interference Scenario (Jul-2008)