The International Space Station Geocam
Project
William Louis Stefanov
NASA Johnson Space Center, Houston, TX USA
International Space Station Research Investigations
and Experiments Conference
April 9-11,2015 Moscow, Russia
The International Space Station Geocam Project
Presentation Overview:
Project Drivers
Project Objectives
Development Pathway
Status
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The International Space Station Geocam Project
Geocam Project Team Members
NASA Johnson Space Center
J. Heydorn, S. Hunter, J. Lee, E. Nielsen, E. Smith, M. Trenchard,
M. Urano
NASA Ames Research Center
M. Dille, T. Smith, Y. Lee
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The International Space Station Geocam Project
Project Drivers
o Current geolocation of USOS ISS astronaut
photo products (image centerpoint) does not
meet modern user expectations for image
data – fully geolocated (all pixels have
geographic coordinates) data is now the
norm
o Data delivered to United States Geological
Survey is available to International Disaster
Charter requestors but not immediately
useful without full geolocation
o Spatial analysis, time series change detection
analysis
o Media outlet use with maps, animations
o Manual full geolocation of handheld imagery
is labor-intensive (<1 hr – 2 hrs per image)
using current software; Geocam system
provides an innovative and more efficient
approach
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The International Space Station Geocam Project
Astronaut photography from ISS is collected using COTS digital cameras with no native geolocation
information. Camera look direction and viewing angle is unconstrained (left image); therefore the ISS nadir
point is only useful as a starting geographic reference point.
Determination of the correct image centerpoint location within the envelope of uncertainty (right image)
currently requires manual comparison of image features with other geolocated images or maps.
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The International Space Station Geocam Project
Project Objectives
o Improve quality of geolocation to enable map overlays
o Improve speed of manual process; enable registering all new Priority 1 photos
(~80/day)
Angular
Error
Geolocation
Search
Pixel Error
Current
45o
(360 km)
191x area
(60 minutes)
1200 pixels
(7500 m)
o Slow manual process geolocates
< 10% of 400+/day photos
GeoCam
(Minimum)
15o
(120 km)
21x area
(7 minutes)
50 pixels
(330 m)
o Provide automated rough geolocation
data for all new photos; lay
groundwork for automated precision
geolocation
GeoCam
(Ideal)
5o
(33 km)
o Current process provides
low-precision “center-point only”
information
Condition
3x area
(1 minute)
@ 400 mm
10 pixels
(65 m)
o Funded by ISS Program to Phase I/II – development of ground system: GeoRef
software/server configuration, and proof-of-concept calibration camera
hardware demonstration (Spring 2015)
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The International Space Station Geocam Project
Development Pathway – GeoSens Hardware

LEFT-FACING
SECONDARY
CAMERA

POINTING
CALIBRATION TARGET
IN ISS INTERIOR
LG Nexus 5
Pointing Calibration Targets mounted in
cupola
 Ideally, semi-permanent mounting
to avoid recurring setup time
During photography, ensure some
calibration target is occasionally in view
of secondary camera
 (Example: In view for at least 1
second every 5 minutes)
 Given proper target placement, this
may happen without explicit
astronaut attention
 Sensor package can use an audible
tone to indicate rare cases when
astronaut attention is needed
 Trade-off: More targets vs. higher
chance calibration activity is needed
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The International Space Station Geocam Project
Development Pathway – GeoSens Hardware


1 second ~
7 km

Our approach is to record the sensor package
timestamp and pose information when the camera
shutter is released
 Sense shutter release via Nikon 10-pin
connector
Later, on the ground, timestamp will be combined
with ISS position history to infer camera position

At ISS orbital speed, one second time error =
about 7 km position error

Sensor package clock should have subsecond
absolute accuracy
Currently determining easiest approach to receive
accurate clock corrections via WiFi
 Will use ISS Network Time Protocol (NTP)
ISS Ground Track
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The International Space Station Geocam Project
Development Pathway – Information Downlink
Calibration
Target
Photos
(astronaut
media transfer)
Sensor
Package
ISS
GROUND
Geocam Meta-Data
(automated WiFi, no
astronaut impact)
Photo
Downlin
k
Photo
Archive
ADDING COMPONENTS
IN GREEN
JSL Storage
GeoCam Meta-Data Downlink
(< 1% photo data volume)
Geocam
Server
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The International Space Station Geocam Project
Development Pathway – GeoRef Software (NASA Ames)
Clean, intuitive interface for rapid tie-point georeferencing of images
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The International Space Station Geocam Project
Development Pathway – GeoRef Software (NASA Ames)
Reasonable rotation and geolocation to base image with only 3 tie points
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The International Space Station Geocam Project
Project Status and Next Steps
o GeoRef software in beta test by NASA JSC team
o GeoSens package in prototype development
o Demonstration of GeoSens tool to ISS Program, to obtain Phase
III/IV funding (first half 2015)
o Deliver GeoRef software for integration and implementation
with existing systems at NASA JSC; GeoSens package
development to Critical Design Review stage (second half 2015)
o Deliver flight units to ISS during second half of 2016; transition
to operational use of complete Geocam system
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The International Space Station Geocam Project
Thank you for your attention!
Questions or Comments?
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