Ancillary Data Production for Cubesats

50 Pages·2017·3.34 MB·English

Navigation and Ancillary Information Facility (NAIF)
“SPICE”
Might Help Cubesat and SmallSat Missions
Compute Observation Geometry
from Ancillary Data
Charles Acton
Jet Propulsion Laboratory, California Institute of Technology
charles.acton (at) jpl.nasa.gov
The research described in this publication was carried out at the Jet Propulsion Laboratory, California
Institute of Technology, under a contract with the National Aeronautics and Space Administration
Navigation and Ancillary Information Facility (NAIF)
Topics
• What are “ancillary data?”
• Why are these data needed?
• Producing and using ancillary data using NASA’s
“SPICE” system
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Navigation and Ancillary Information Facility (NAIF)
A Pictorial of Ancillary Data
Orientation
Antenna and size/shape
reference of Earth
frame J2000 reference frame
(ICRF)
Sun
Spacecraft
Reference frames
Earth
•
Positions & Velocities
Solar System Barycenter
Orientations
Sizes/shapes
Instrument
reference frame
Relative positions
Instrument Pointing
Spacecraft of spacecraft and
Time Conversions reference frame solar system bodies
Orientation
of spacecraft
Orientation
and
size/shape
of planet
The Solar System
Planet-fixed
reference frame
Pointing of
Instrument Planet
field-of-view
Time Conversion
Calculations 3
Navigation and Ancillary Information Facility (NAIF)
Examples of Using Ancillary Data
• Help mission designers converge on a spacecraft
trajectory design
• Compute observation geometry parameters
needed by engineers for…
– communications station view period calculations
– antenna pointing
– thermal and telecom analyses
• Compute observation geometry parameters
needed by scientists for…
– science observation planning
– science archive preparation
– science data analysis
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Navigation and Ancillary Information Facility (NAIF)
Contrast
“Ancillary Data” vs. “Observation Geometry”
Ancillary Data Observation Geometry
(Files) (Derived parameters)
• Altitude = xxx km.
• Latitude = xxx deg.
• Longitude = xxx deg.
• Phase angle = xxx deg.
• etc.
Spacecraft trajectory
Some
Software
Observation Geometry
(Conditions)
Spacecraft orientation
• Spacecraft is in occultation by Mars
• Altitude is at a global maximum
• Phase angle is in the range of 24 to 28
degrees
• etc.
Spacecraft clock correlation
etc.
5
Navigation and Ancillary Information Facility (NAIF)
When are Ancillary Data Used?
Mission concept
development
Pre Phase A
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Navigation and Ancillary Information Facility (NAIF)
When are Ancillary Data Used?
Mission concept Mission design
development validation
Pre Phase A Phases A -D
Launch
Mission
design
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Navigation and Ancillary Information Facility (NAIF)
When are Ancillary Data Used?
Mission concept Mission design Detailed science Science archive
development validation observation planning preparation
Pre Phase A Phases A -D Phase E
Launch Mission End
Mission Mission operations Initial science
design support data analysis
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Navigation and Ancillary Information Facility (NAIF)
When are Ancillary Data Used?
Mission concept Mission design Detailed science Science archive
development validation observation planning preparation
Pre Phase A Phases A -D Phase E Phase F
Launch Mission End
Mission Mission operations Initial science Science archive
design support data analysis user support
Full Mission Lifecycle
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Navigation and Ancillary Information Facility (NAIF)
Examples of Challenges in
Producing Planetary Ancillary Data
• Almost everything is moving and/or rotating
• Multiple reference frames, coordinate
systems and time systems are used
• Size and shape estimates for target bodies
are constantly evolving
• Improvements in spacecraft trajectory and
orientation often occur
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