Are there other worlds out there?
Nicolas Camille Flammarion Folie 1
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Are there other worlds out there?
Galileo Galilei; 1564 - 1642
Folie 2
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung 1 Harald Michaelis, DLR-PF-PS Folie 3
EJSM- Jan. 18th 2010; ESTEC
Planetary Science
-
Technology
Die Entwicklung von neuen Technologien, Messverfahren und Instrumenten haben einen entscheidenden Einfluß auf den Erkenntnisgewinn Folie 4
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
DLR-Institute of Planetary Research, Berlin
Planetary Science & Sensor Design, Test & Calibration
Head: Prof. Tilman Spohn
Planetary Sensor Systems: Harald Michaelis Vortragstitel
5
Planetare Sensorsysteme
Design und Entwicklung von Instrumenten Entwurf von Bordsoftware; Tests, Kalibrierung
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Planetare Sensorsysteme Zusammenarbeit mit Industrie und wiss. Institutionen eine Spezialisierung: optische Instrumente, Kameras
Stichwort: Systemingenieur; Stichwort: Projektingenieur;
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Planetare Sensorsysteme
Studiengänge: - Physik, Elektrotechnik- Elektronik,
- Informatik/Informationstechnik, - Technische Optik,
- Luft- und Raumfahrttechnik,
- Maschinenbau/Konstruktion,
- Technikerausbildung – Elektronik
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Einleitung Einteilung von Instrumenten Typische Payload einer Raumsonde Welche Technologien sind von Bedeutung Unterschiede zu erdgebundenen Instrumenten Umweltbedingungen Messaufgaben Aufbau und wesentliche Kenngrößen von Instrumenten Einfache Berechnungen Ablauf einer Instrumententwicklung Beispiele Ausblick
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Einteilung von Instrumenten Nach dem Wissenschaftsgebiet Nach der zu messenden Größe Nach der Instrumentkategorie Nach dem Spektralbereich Nach dem Abstand zum Meßobjekt
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Einteilung von Instrumenten Nach dem Abstand zum Meßobjekt in-situ Instrumente Remote Sensing Instrumente
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Methodische Grundlagen der Fernerkundung
Klassifizierung von Fernerkundungssystemen Systemtypen
aktive Systeme
.
abbildend (imaging)
Abbildender Radar
SLAR
Laseraltimeter
passive Systeme
nicht abbildend
sounding
Meßbereich
Leistung
Radaraltimeter
abbildend
nicht abbildend
reflektierte Solarst.
Scatterometer
Luftbildaufnahme
sounding
Therm. Eigenstrahl.
VIS/NIR Scannner
Thermal IR Scanner
Passive Mikrowellen Radiometer
SAR Folie 12
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Typische Payload einer Raumsonde Ocean Team Laser Altimeter
LA
Radio Science
RS
Ice Team Ice Penetrating Radar
IPR
Model payload is a proof-ofconcept example Other instruments may be viable
Chemistry Team Vis-IR Imaging Spectrometer
VIRIS
UV Spectrometer
UVS
Ion and Neutral Mass Spectrometer
INMS
11 model payload instruments [including radio science] Emphasizes Europe investigations
Geology Team Thermal Instrument
TI
Narrow Angle Camera
NAC
Wide Angle Camera and Medium Angle Camera
WAC + MAC
Fields an Particles Team Magnetometer
MAG
Particle and Plasma Instrument
PPI
Enables robust Jupiter system science Employs a cooperative, efficient teaming approach
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Technologies needed for Planetary Research :
Electronics
Optics
Mechanical Technologies
Thermal Technologies
Software (IT)
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Unterschiede zu erdgebundenen Instrumenten
Environment
Small mass and volume
Low power consumption
Low data rate
autonomy
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Umweltbedingungen The space environment is what makes a spaceborne instrument different than any on Earth Mechanical shock and vibration Launch loads Vacuum Thermal Radiation Debris/micrometeorites
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Launch loads Steady-state booster acceleration Transient booster ignition / burn-out Vibro-acustic loads, engine vibrations Avoid resonance
Shocks from separation events (stage / fairing separation) → Structural mathematical model is developed and verified by testing Folie 17
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Vacuum Heat exchange is only radiative
Convection cannot be use for cooling (fan not useful for cooling) Outgassing Materials evaporate at atomic level (No liquid lubricants, deposition on optical surfaces, shrinking of composites, etc.)
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Thermal environment Extremely high and low temperatures w/o convection Temperatures
Earth surface:
-90 °C / +14 °C / +60 °C
Sun:
+5500 °C
Deep space:
-269 °C
Planetary surface:
-200 °C / 450 °C
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Ionizing radiation & high-energy particles Protons, Electrons and heavy ions trapped by planets’ magnetic field
Solar energetic particles (solar storms and flares) and Cosmic radiation (high energy nuclei from within and from outside our galaxy)
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Ionizing radiation & high-energy particles
Effects Reduce the operational capability of semiconductors (Solar Arrays & electronics) Atom displacement and local ionization, which changes the potential and dielectric capabilities (Single Events, Latch-ups) UV radiation damages surfaces, in particular instrument optics
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
EE2007 Mission Dose-Depth Curve by Mission Segment
- Copy from presentation ‘Characterization of Radiation Environments- Europa Orbiter’; Insoo Jun; June 2008; JPL Folie 22
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung
Messaufgaben Radiometrische Messung Detektion lichtschwacher Objekte Spektrale Messung Hochauflösende räumliche und spektrale radiometrische Messung
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Messaufgaben Detektion lichtschwacher Objekte hochempflindliches Radiometer (Detektor, Optik)
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Transit um HD209458
HD209458b: Umlaufzeit = 3.52 Tage Radius = 1.3 Jupiterradien
Masse = 0.63 MJupiter Dichte = 270-490 kg/m3 STARE:
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(Charbonneau et al., 2000)
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Example: Detection of low light objects
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EJSM- Jan. 18th 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Messaufgaben
Hochauflösende räumliche und spektrale radiometrische Messung Multispektralkamera, abbildendes Spektrometer
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Olympus Mons Westabbruch
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Reflectance Spectrum
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Aufbau von Instrumenten & wesentliche Kenngrößen
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Architecture of Imaging Systems
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EJSM- Jan. 18th 2010; ESTEC
HRSC Camera unit and Digital unit Designed for Mars-Express
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
HRSC/SRC Camera-Optics
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
HRSC: High Resolution Stereo Camera
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Data Flow in imaging systems
illumination
object
optics
optical filter
spectral sensitivity
sensor architecture
noise sources
signal processing
image compression
image storage
Data format. & Transmiss.
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Data Flow in imaging systems e.g. illumination device, optical calibration source, scanning mirror (object side), ...
Optical Support Equipment
CMD, HK
Detector Electronics: CLK Drivers, Signal Chain / ADC, Controller CCD / APS / IR array
Filter Reel / Prot. Cover
Camera Optics / Spectrograph
Detector (FPA)
Camera Head
Detector Electronics
CMD, HK
Imaging System
Mass Memory
Peripheral Equipment
Image Data Buffer
IPU / IME (Pre-Processing, Image Compression)
Telemetry (S/C)
Ground Station / User
CMD, HK
CMD, HK
e.g. deployable boom, movable platform, ...
Spacecraft / Lander / Carrier
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Spectral Range Spectral Resolution Dynamic Range (DR) Sensitivity Signal to Noise Ratio (SNR) Resolution (spatial)
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Spectral Range
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen ‘Visible‘ Imaging Sensors are keyinstruments in many space based exploration missions‘ – Why? Stars and planets radiate a major part of their spectrum in the VIS/NIR Our brain is optimized for ‘image processing and interpretion‘
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Spectral Range
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Wavelength Coverage
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Spectral Resolution (R) (spectral resolving power) Beispiel:
= 1000nm; Δ=1nm R= 1000
R Folie 42
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Beispiel Spectral Range and Resolution SR: 2-5μm
R=1500-2900
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Spectral Range Spectral Resolution Dynamic Range (DR) Signal to Noise Ratio (SNR) Sensitivity Spatial Resolution
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Dynamic Range:
S Max DR S Min
z.B: SMax: 1V; SMin: 1μV DR= 1000 DRdB= 60dB
S Max DRdB 20 log( )dB S Min
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Signal to Noise Ratio (SNR)
z.B: S= 4000ph; QE: 0.4 Nreadout: 40e
S SNR N SNR
S m
i
N 2i
SNR= 28
Folie 46
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen SNR
Signal to Noise Ratio (SNR)
S m
i
z.B: S= 4000ph; QE: 0.4 Nreadout: 40e
SNR
N 2i
4000 * 0.4 402 4000 * 0.4
SNR= 28
Folie 47
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Key Performance Parameters and key components
Noise: P(λ) Noise
S0 +N Noise
Noise is everywhere!
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EJSM- Jan. 18th 2010; ESTEC
Key Performance Parameters and key components SNR: high signal output with low noise
Noise sources: -Object Background noise
- Proper filtering
-Stray light
-Proper baffling, surface quality, coatings
-Photon shot noise
-Limitation at high signal levels
-Detector readout noise (Nr)
-Limitation at low signal levels
-Thermal shot noise (Id)
-Detector material, cooling
-Pixel non-uniformity
-Calibration
-Electronics noise
-Art of engineering, design, grounding Folie 49
EJSM- Jan. 18th 2010; ESTEC
Key Performance Parameters and key components
Detector Noise Noise reduction is the only way if detectors sensitivity can not further increased
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EJSM- Jan. 18th 2010; ESTEC
Performance and Design Requirements
but if we have weak signals
Nsys ~ SQRT(Nreset2 + Nread2 + Ndark2 + NADC2 + Noffschip2 )
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
KTC Noise THERMAL NOISE =
4k TBR
WHERE K = BOLTZMANN’S CONSTANT –23 = 1,38 x 10 T = ABSOLUTE TEMPERATURE (K) B = NOISE POWER BANDWIDTH (Hz) R = RESISTANCE (Ohms)
π 1 f3db B= 2 4RC THERMAL NOISE =
kT C rms Volts kTC
= 1.6x10 -19 rms e = 400
C
-
rms e
-
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Typische Kenngrößen Spectral Range Spectral Resolution Dynamic Range (DR) Signal to Noise Ratio (SNR) Sensitivity Spatial Resolution
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Key Performance Parameters and key components
Sensor Sensitivity: distinguish between point sources and extended sources For extended sources: (e.g. planetary observation): So /4 *1/F#2 Ad Tint * ?P(ë) * ç (ë ) dë
P(λ) So So = π/4 * 1/F#2 Ad Tint *∫P(λ)* η (λ ) dλ.
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EJSM- Jan. 18th 2010; ESTEC
Key Performance Parameters and key components Sensor Sensitivity (extended sources): So = P*π/4 Δλ η 1/F#2 Ad Tint.
η: quantum efficiency
Ad : Pixel area F#: f- number Tint: integration time With Ad= b2 (square pixel): So = P*π/4 Δλ η 1/F#2 b2 Tint. Folie 55
EJSM- Jan. 18th 2010; ESTEC
Key Performance Parameters and key components Sensor Sensitivity (extended sources): How to increase the sensors output signal η:
Select a detector with best quantum efficiency
Ad :
Increase the pixel size
F#:
Increase the aperture ratio
Tint:
Increase the integration time
Folie 56
EJSM- Jan. 18th 2010; ESTEC
Instrumentelle Grundlagen der Fernerkundung
Fernerkundungssysteme Der Along-Track Scanner ( Pushbroom Scanner) IFOV pro Detektorpixel = 1mrad
Problem Integrationszeit:
Tint < Tdwell Die Dwell Time eines Pushbroom Scanners ist durch die Fluggeschwindigkeit relativ zum Boden bestimmt. Dwell Time =
Scannrichtung
Höhe = 10km
Bodenauflösung/ Bodengeschwindigkeit
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
. -
Sensitivity – SNR - Optimization
-F#
-Increase resources
-Pixel Size
-Increase resources
-Readout Noise
-Detector/Electronics Optimiz.
-Dark Current
-Detector/Material/- Cooling
-Quantum Efficiency
-Detector/coating- optimization
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EJSM- Jan. 18th 2010; ESTEC
Detectors and key performance parameters 1. Quantum Efficiency - Interaction of the Si- lattice with „visible light‟- photons
MOScell
Gate SiO2
+ - generating of electron-hole pairs
- accumulation of the photoelectrons
Sisubstrate
Only a fraction of the light falling on the detector will actually be detected Folie 59
EJSM- Jan. 18th 2010; ESTEC
Front Illuminated CCDs
Photons
electrod e structur e
sensitive region
Silicon oxide
10-20 µm
1 pixel
Bulk silicon
Photons absorbed below the sensitive region will not form part of the signal 500 µm
Folie 60
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Front and Back Illuminated CCDs 100
BV (550nm) 90
BU (350nm)
BR DD (850nm)
80 70
BU2 (250nm)
60
BN (no coating)
50 40 30 20 10 0 150
250
350
450 550 650 Wellenlänge (nm)
750
850
950
1050
Quanteneffizienz von Back Illuminated CCDs und Deep Depletion CCDs (BR DD) mit verschiedenen Antireflexionsbeschichtungen bei –90°
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
High (spatial) Resolution Imaging
Die räumliche Auflösung ist die Fähigkeit zwei benachbarte Objekte eines Bildes voneinander zu unterscheiden. Es ist die minimale Distanz zwischen zwei Objekten, für welche die Bildobjekte unterschieden und separiert werden können. Folie 62
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
High (spatial) Resolution Imaging Characteristics: Spatial Resolution depends on:
-
Geometrical magnification Diameter of optics ‘Optical quality’: aberrations Platform stability Atmospheric turbulences Stray light Contrast ratio
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Optics: Typical Specification Procedure: -
Typical design Approach:
-
1. IFOV (pixel resolution) Definition
-
2. Choice of a detector (Pixel Size)
-
3. Calculate focal length
-
4. Select f# number (or the aperture of the optics) according to diffraction limit and/or SNR estimations
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EJSM- Jan. 18th 2010; ESTEC
High (spatial) Resolution Imaging
Spatial Resolution depends on: Characteristics: -
Geometrical magnification Object at infinity Pixel (image) G P P g f IFOV f
G g Focal length (f)= IFOV/Pixel size
Beispiel : G 1m g 200km IFOV 5rad Folie 65
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
-
…
-
4. Select f# number (or the aperture of the optics) according to diffraction limit and/or SNR estimations
F#= f/D f: focal length D: Aperture of the Optics
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EJSM- Jan. 18th 2010; ESTEC
Examples:
F# is typical between 5 – 10!
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EJSM- Jan. 18th 2010; ESTEC
Conceptional Design - Optics
F# is typical between 5 – 10! What does it mean from resolution point of view?
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EJSM- Jan. 18th 2010; ESTEC
Conceptional Design - Optics
F/- Number and Pixel-Sampling
2.44 *
Intensity
D * f 2.44 * * F # with
800nm 1.22
1.22
2.44 * F#
n*
F # 10 * f 20m
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EJSM- Jan. 18th 2010; ESTEC
Conceptional Design - Optics
F/- Number and Pixel-Sampling Pixelsize
Bdiff
+
or
Bdiff
=
Bdiff
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EJSM- Jan. 18th 2010; ESTEC
Instrumentelle Grundlagen der Fernerkundung
Modulations-Übertragungs-Funktion (modulation transfer function MTF) Die Modulation m ist definiert als: m = (Imax - lmin) / (lmax + lmin) ≤ 1 Die MTF eines bildgebenden Systems ist definiert als Modulationsrate, die am Detektor produziert wird, zur Modulationsrate des Targets. Sie ist eine Funktion der Raumfrequenz. Sie kann für FE-Systeme und/oder getrennt für Subsysteme angegeben werden.
MTF
b a
Räumliche Frequenz q
MTF für typische Filme (a) geringe Auflösung, (b) hohe Auflösung. Literaturhinweis: McKinney R. 0. Photographic materials and processing in, Salma C.C., ed Manual of photogrammetry, 4. Edition, eh. 6, p. 305-366, American Society of Folie 71 Photogrammetry, (1990) Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente der Fernerkundung
Kameras: Effekte des optischen Systems
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Optics Resolution and MTF MTFdiff (f) = 2/Pi * (arccos(f/fo) – (f/fo)* 1-(f/fo)2 . fo = 1/(F#) ; fo: spatial sampling frequency in line-pairs/mm
1
MTF of a diffraction limited optics
0 Fo in lp/mm
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EJSM- Jan. 18th 2010; ESTEC
Instrumentelle Grundlagen der Fernerkundung
Bildgebende Systeme und ihre Eigenschaften: Räumliche Auflösung
Auflösungs- und Beobachtungstargets mit hohem Kontrast. Betrachten Sie das Bild (HCVorlage) aus 5 m Entfernung. Für A finden Sie den Set der dicht platziertesten Balken, die Sie auflösen können. Für B finden Sie die engste Linie, die Sie beobachten können.
Auflösungs- und Beobachtungstargets mit mittlerem Kontrast. Betrachten Sie das Bild aus 5 m Entfernung. Für A finden Sie den Set der dicht platziertesten Balken, die Sie auflösen können. Für B finden Sie die engste Linie, die Sie beobachten können. Vergleichen Sie mit dem Beispiel des hohen Kontrastes. Folie 74
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Optics Resolution and MTF MTFdiff (f) = 2/Pi * (arccos(f/fo) – (f/fo)* 1-(f/fo)2 . fo = 1/(F#)
At F/5...F/10:
The resolution of the optics is (in most cases) higher than the `Pixel-resolution´
The system resolution is pixel limited Dr.H. Michaelis Tel.:+49-30-67055 364, Fax:+49-30-67055 384 e-mail:
[email protected]
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EJSM- Jan. 18th 2010; ESTEC
Optics Resolution and MTF MTFdiff (f) = 2/Pi * (arccos(f/fo) – (f/fo)* 1-(f/fo)2 .
fo = 1/(F#)
1
0 Fo in lp/mm
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EJSM- Jan. 18th 2010; ESTEC
Optics Resolution and MTF MTFdiff (f) = 2/Pi * (arccos(f/fo) – (f/fo)* 1-(f/fo)2 .
fo = 1/(F#)
1lp
Pixel
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EJSM- Jan. 18th 2010; ESTEC
Optics Resolution and MTF MTFdiff (f) = 2/Pi * (arccos(f/fo) – (f/fo)* 1-(f/fo)2 .
fo = 1/(F#)
Dr.H. Michaelis Tel.:+49-30-67055 364, Fax:+49-30-67055 384 e-mail:
[email protected]
Folie 78
EJSM- Jan. 18th 2010; ESTEC
Optics Resolution and MTF Example / Test campaign
1.
Moon image taken with
D: 100mm : f: 1000mm
F#: 10
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EJSM- Jan. 18th 2010; ESTEC
Optics Resolution and MTF Example / Test campaign
95Her with SRC – 6.3”
2. Mars : 28.8.2003: F/10
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EJSM- Jan. 18th 2010; ESTEC
Optics Resolution and MTF Example / Test campaign
2. Mars: 28.8.2003: F/20
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EJSM- Jan. 18th 2010; ESTEC
Optics Resolution and MTF Example / Test campaign
2. Mars: 28.8.2003: F/40
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EJSM- Jan. 18th 2010; ESTEC
Optics Resolution and MTF – large F#
The problem with F# > 10 is: - lower SNR What we can do: High QE detectors larger filter bandwidth larger integration-time – e.g. by CCD-TDI operation
or motion compensation
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EJSM- Jan. 18th 2010; ESTEC
Principle of APS-TDI
t1 t² t3 t4
vg
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Institut WP - Abteilung Sensortechnologie
Used Linear CCD, CCD Arrays and CMOS Detectors at DLR
5 years
Cassini-Huygens- DISR MPS; 512x512
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Large Focal Plane with CCD Proximity Electronics
9k x 7k CCD (Philips\DLR\Steward Observatory) Folie 86
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
5 * 12 k Linear CCD Arrays on a Focal Plate
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
MOSES MOSES 7888: Modular (CCD) Sensor Electronics
CCD TH7888
1024 x 1024pixel
Spectral range
250-1020 nm
Pixel size
14 microns
Readout Rate
1Mpixel/s
Exposure Time
1 ms – 60s
Resolution
14Bit
designed by: M. Tschentscher,
T. Behnke, H. Michaelis Folie 88
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
~ 750 mm 0.92 deg
The GAIA mission The ASTRO Focal Plane 600 mm 0.737 deg
ASM1 ASM2
AF1-11
Astro field #1
< 4 mm
< 1 mm
BBP
Astro field #2
AF CCDs: Cell size: 49 x 60 mm² Active area: 45 x 59 mm² (4500 x 1966 pixels) Pixel size: 10 x 30 µm² ASM and BBP CCDs: Cell size: 30 x 60 mm² Active area: 26 x 59 mm² (2600 x 1966 pixels) Pixel dimensions: 10 x 30 µm²
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
GAIA- Focal Plane Demonstrator
TDMD:
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung
Ablauf einer Instrumententwicklung Beispiele – aktuelle Projekte
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente und Technologien zur Planetenerkundung Ablauf einer Instrumententwicklung 1. Analysis of Science Requirement and translation into instrument requirements 2. Phase- A: Conceptional Instrument Design 3. Phase-B: Preliminary Instrument Design: i/f- Definition, Breadboarding 4. Phase-C: Instrument Final Design, CDR, STM, EM 5. Phase-D: Flight Model Development
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Deliverable Items for 2 different Model Approaches •Classic Qualification-Model Approach -> clear task sharing: qualification >< flight H/W -> early H/W design freeze -> refurbished EQM -> FS
STM Structural /Thermal Model
EQM Electrical Qualificatio n
FM
FS
Flight Model
Flight Spare
Model
•The Protoflight-Model Approach -> stressed by qualification model = flight H/W -> reduced costs (?)
STM Structural /Thermal Model
EM Electrical Model
PFM
Proto Flight Model
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Present Activities and Outlook
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente der Fernerkundung
Aktive Systeme: LASER Altimeter
Mars Orbiter Laser Altimeter (MOLA) Einsatz:
Mars Global Surveyor
Eigenschaften: Diodengepumter Laser als Transmitter, Nd: YAG Laser Wellenlänge 1064 nm, Pulsrate: 10 HZ, Energie: 48 mJ/Pulse LaserSpot: 0,4 mrad, Empfänger: Spiegel 50 cm parabolisch, FOV: 0,85 mrad Vertikale Präzision (shot-to-shot) 37,5 cm, Spotgröße am Boden 130m
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Instrumente der Fernerkundung
Aktive Systeme, MOLA
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
BELA- Overall Design - End 2009 Receiver
ELU
Transmitter
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Bepi Colombo Laser Altimeter (BELA) BepiColombo Laser Altimeter In Betrieb bei einer Oberflächenentfernung zwischen 400 und 1050 km (60% der Orbitdauer)
12 kg, 50 W 50 mJ Pulsenergie bei 10 Hz 1064 nm Laserwellenlänge 250 m Abstand der Messpunkte entlang der Flugrichtung 25 km Abstand der Messpunkte am Äquator quer zur Flugrichtung
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Subsysteme
Teleskop
Detektor Rangefinder Datenverarbeitung
Laserkopf
Laserelektronik
Powerkonverter
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Laser link budget
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Alignment
Millenium Dome
Receiver FOV
Laser spot
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Prinzip der Laseraltimetrie Erfassen der Oberflächentopographie eines Körpers
Methode: 1.
Aussenden eines Laserpulses und Start der “Stoppuhr”
2.
Der Laserpuls wird an der Oberfläche reflektiert
3.
Emfpangen des reflektierten Laserpulses
4.
Berechnung der Entfernung zur Oberfläche
Image credit: Thomas et al., 2007 Folie 103
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
BELA- DPU Electrical Design - End 2009
ELU- Housing
Test of Data Processing Module and RangeFinder Folie 104
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
From Science Requirements to Instrument Design – ExoMars PanCam Mission Environment: ESA‘s ExoMars Rover Mission (launch planned for 2018)
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
From Science Requirements to Instrument Design – ExoMars PanCam
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
From Science Requirements to Instrument Design – ExoMars PanCam Phase B1 Design: PanCam includes Two Wide Angle Cameras (WACs), 34° FoV, each eye equipped with a 12-positions filterwheel for stereo, multispectral observations A High Resolution Camera (HRC), 5° FoV, equipped with an on-chip RGB filter and an autofocus mechanism Arranged on a common Pan-Tilt Unit (PTU) on top of the ExoMars rover mast assembly Wide Angle Cameras (WACs): 34 FoV, 1024 x 1024 CCD, multispectral filter set (12 filters/eye) IFOV 580µrad/pixel horizontal =>1.2mm/pixel scale at 2m distance and 58mm/pixel scale at 100m Fixed focus (between 1.2m and infinity)
HRC
High Resolution Camera: 5° FoV, 1024 x 1024 CIS, RGB filter on-chip IFOV 83 µrad/pixel => pixel scale of 0.17mm/px at 2m distance and 8.3mm at 100m (magnification of a factor of ~7 compared to the WACs) Autofocus capability (between 0.9m and infinity) …arranged on a common pan-tilt unit on top of the rover mast WACs with Folie 107 Filterwheels Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
From Science Requirements to Instrument Design – ExoMars PanCam Field/Laboratory Tests of functional performance: AMASE (Arctic Mars Analogue Svalbard Expedition) in August 2008 and 2009 (Mission Simulation with PanCam as part of an ExoMars-representative instrument suite) ExoMars Rover Vision Test with Astrium UK in a Sandy Quarry, Bedfordshire, UK (PanCam integrated on the ExoMars Rover Chassis Breadboard ‚Bridget„) Two ‚Geological Blind Tests„ in the ‚Planetary Analogue Terrain„ Lab of the Space Robotics Group, Aberystwyth University, Wales
HRC, target 2
1.2
1
2
quartz
Target 1 Target 2 Target 3
0.8
HRC, target 1 0.6
1
0.4
3
quartz 0.2
HRC, target 3 0 400
WAC
600
800
goethite Folie 108
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
1000
ExoMars PanCam Field Testing (2)
A B
A A
1
B
JS02 BC CF BC
CT/CF
H2O
?
WAC
0.9 0.8
Reflectance
0.7
HRC
0.6 0.5 0.4 0.3
HRC
0.2 0.1
Absorption bands: CT = Carotenoids; CF = Chlorophyll a & b; BC = Bacteriochlorophyll.
0 400
500
600
700
800
Wavelength (nm)
Harald Michaelis; DLR-PS – EJSM
Pink Meeting
at
Orange Green Jan. 18-20 2010;
900
1000
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White ESTEC
ExoMars PanCam Field Testing (3)
Bockfjorden, Troll Springs
HRC
WAC
Clearly visible patches of fossilized microbial mats
Spectrum consistent with carbonate. W/o any active biological pigmentation present, the detection of fossilized biomats is not possible
.
18x1 HRC mosaic Folie 110
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
AsteroidFinder Compact satellite based on DLR SSB design Quasi-Polar, Low-Earth, Sun-synchronous Orbit (650-700 km alt.) 25-cm wide-field optical telescope Spacecraft and telescope layout optimized for observations at small solar elongations (30 to 60 ) No consumables. Attitude control through reaction wheels and magnetic torquers for wheel de-saturation Folie 111
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Telescope configuration F.L.
760 mm
Aperture
>400 cm2
f ratio
3.4
CCD array
4 x 1024 x 1024
Pixel size
13 µm
Corrected field
1.40° radius
IFOV
3.5”/pix
Design drivers In-field and out-of-field straylight rejection Maximize aperture for the given envelope
Large FOV and excellent optical quality Thermal requirements Folie 112
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Future Missions: EJSM/JEO:
Launch: 2020
Arrival: 2026 Folie 113
Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC
Thanks for your attention
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Harald Michaelis; DLR-PS – EJSM Meeting at Jan. 18-20 2010; ESTEC