Spacecraft Imaging Systems

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Spacecraft Imaging Systems Dr Tim
Yeoman Department of Physics and Astronomy
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Module structure
The module comprises 4 lectures and 6 workshop
sessions. Students will work in groups of 4. The
first lecture provides introductory and
background material. The remainder of the
lectures will (largely) comprise a presentation
of the previous weeks workshop progress by each
group.
Full module description and timetable
http//www.ion.le.ac.uk/yxo/lectures.html
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Project groups
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Assessment
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Timetable
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What do you get out of it?

• Experience of working as part of a team
• An insight into imaging systems for planetary
  landers
• iii) Practical experience in instrument
  development and calibration

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What do I get out of it?

• To see you make a number of presentations
• Each group will give a 10 minute presentation
  (with slides) on progress and problems with the
  previous weeks workshops. A different member of
  the group will present each week.
• An individual project report
• Substantial report that covers background,
  operation, theory, error analysis etc.

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Assessment
The module is worth 7.5 credits. Assessment is
divided into two parts and marks are awarded as
follows 1) Practical skills during workshop
sessions (25) 2) Individual project report
presentations (75)
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Spacecraft imaging
Why does a spacecraft need an imaging system?
Vision is one of our primary sources of
information Useful for Scientific
observations Mission planning and
operations Maintenance
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Planetary lander imaging systems
Aspects for consideration What is the purpose
of the imaging system? Determines resolution,
field of view, focal length, illumination,
colour or B/W, wavelength sensitivity. Twin
cameras adds stereo capability (3D image
creation). Also gives redundancy. Environment T
emperature range, vacuum or atmosphere, radiation
dose
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Planetary lander imagers
Viking panoramic scan cameras 12 pixel diode
array, 64 grey scales. Image created by scan
mirror (elevation) and camera rotation (azimuth).
IMP (Imager for Mars Pathfinder) camera system on
Pathfinder lander single monochrome 250 kpixel
CCD detector, 4096 grey scales (350 actual).
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Planetary lander imagers
Beagle2 PAW showing position of SCS (Stereo
Camera System) two monochrome 1 Mpixel CCD
detectors, 1024 grey scales (140 actual)
MER (Mars Exploration Rovers) Panoramic camera
two monochrome 1 Mpixel CCD detectors, 200 actual
grey scales.
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Planetary lander images
First colour image from Spirit MER
Viking 1 colour image
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Planetary lander images
Opportunity front wheel dug into Martian soil
HazCam image
Spirit rear NavCam image
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The Problem
The European Space Agency (ESA), in their wisdom,
have contracted your group to prototype a stereo
imaging system for a planetary lander. The
scientific aims of the imaging system are to
provide information that will assist with 1)
the identification of the geological terrain in
general, up to and including the horizon, 2)
the identification of foreground rock and soil
composition, 3) mission planning and
operations Mission planning and operations
includes identifying objects and areas of
interest. It also includes providing information
for range finding object distance determination.
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System capability
To meet these scientific requirements the system
( imager post-processing) must be capable of
producing 1) Colour images of the planetary
landscape and objects. 2) Estimation of
distances to objects (range finding). 3)
Stereograms.
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Equipment
Planetary lander
Cameras
Junction box
Also supplied are laptop PC, USB cable, tape
measure, tools and Red-Blue glasses
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Software
The laptop is pre-installed with two relevant
software packages
2. PaintShop Pro8
1. TwoStereo.exe
Image acquisition and object position measurement
Image processing etc
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Things you may like to consider

• context
• sample images
• distance estimation method
• calibration
• limiting factors
• practical considerations
• stereo image creation

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Resources and information
Webcam Colour CMOS sensor, 640 (H) x 480 (V)
pixels.
3D imaging Also known as stereograms or
anaglyphs. Can be B/W or colour. Supplied
glasses are Red-Blue.
Planetary missions http//nssdc.gsfc.nasa.gov/pla
netary/planets
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Summary
Workshops (2nd Year Lab) First workshops -
Groups S1 S2 25th and 26th January First
workshop - Group S3 1st and 2nd
February Hour after this lecture use for
background research and workshop planning Next
lecture - All Groups 6th February Presentation
on progress required from each group.
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Sample image from laboratory lander
Go and take some images !