Chart: 1
Adaptive Reconnaissance Golay-3 Optical Satellite
(ARGOS)
Prof David W. Miller
Chart: 2
ARGOS Overview
ISS
Moon
Frictionless Air Bearing
RWA
Surrogate
Ground Station
M.I.T.
Angular Resolution at λ=550 nm: 0.35 arcsec
Wavelength Regime: 400-700 nm FOR
(Field-of-Regard): 120° (full cone)
FOV (Field-of-View)-min: 3 x 3 arcmin
SNR 100 (Min)
Pointing Accuracy: +/- 10 arcsec
Autonomous Operation: > 1 hour
Angular Resolution at λ=550 nm: 0.35 arcsec
Wavelength Regime: 400-700 nm FOR
(Field-of-Regard): 120° (full cone)
FOV (Field-of-View)-min: 3 x 3 arcmin
SNR 100 (Min)
Pointing Accuracy: +/- 10 arcsec
Autonomous Operation: > 1 hour
Wireless
COMM
Station
First field operation in May
Goal :
Demonstrate
the feasibility
of
Interferometry
technology
Goal :
Demonstrate
the feasibility
of
Interferometry
technology
Chart: 3
Full Structure
Chart: 4
Sub-Aperture Manufacturing
TAKAHASHI 8-inch High Precision (RMS WF errors 1/20 λ) Telescope
Final Design
Designed optimized achromatic doublet to convert a focal telescope to afocal with
Magnification m=10
?FK51/BaK2
–? CTE 5.3
–0.0027 RMS Error
–Some sensitivity to thermal shock
–-Manufacturable tolerances
?FK51/BaK2
–? CTE 5.3
–0.0027 RMS Error
–Some sensitivity to thermal shock
–-Manufacturable tolerances
FK51
BaK2
Chart: 5
Relay Optics Design
1. Sub Aperture
2. Collimator
3. FSM+ODL
4. Pyramidal Mirror
5. Beam Combiner
6. CCD
1
2
3
4
5
6
The Advantages of Two Mirror Design
the cost, the controller complexity,
less reflectance loss, smaller possible misalignment
errors, compactness
The Advantages of Two Mirror Design
the cost, the controller complexity,
less reflectance loss, smaller possible misalignment
errors, compactness
Chart: 6
Allowable Structural
Misalignments
B= FSM
rotation
A
B
45-B
45-A+B = 45- B
2B=A
B= 0.5 *A *10 = 5 A. In reality, a factor of 6.4 works well up
to 0.01 degree
Telescope Tilt
[Deg] [arcsec]
FSM Comp
[Deg] Max
0.034 degree
FSM OPD
[mm]
Strehl Ratio
Aberrated
SR
restored
0.0001 0.36 -0.00064 0 0.687 0.982
0.001 3.6 -0.0064 0 0.016 0.979
0.005 18 -0.032 0 0.192 0.907
0.01 36 -0.064 0 0.064 0.604
0.01 36 -0.064 0.0002 0.189 0.859
Magnification m=10
Chart: 7
Passive/Active Actuators
1
2
3
4
5
6
FSM+ODL
? Angular Range +/- 600 μrad
? Angular Res. +/- 0.05 μrad
? Linear Range 12 μm
? Linear Res. 0.2 nm
FSM+ODL
? Angular Range +/- 600 μrad
? Angular Res. +/- 0.05 μrad
? Linear Range 12 μm
? Linear Res. 0.2 nm
FSM MOUNT
?Angular Range +/- 7°
? Angular Res. +/- 0.0008° (14 μrad)
? Linear Range 1 cm
? Linear Res. 1 μm
FSM MOUNT
?Angular Range +/- 7°
? Angular Res. +/- 0.0008° (14 μrad)
? Linear Range 1 cm
? Linear Res. 1 μm
7°
600 μrad
0.05 μrad
FSM
14 μrad Mount
Pyramid Errors
w/o FSM Correction
SR = 0.444
Pyramid Errors
w/ FSM Correction
SR = 0.960
Pyramidal Mirror Pyramidal mount
Chart: 8
Attitude Control System (ACS)
Sensor 2:
Viewfinder
Sensor 2:
Viewfinder
ACS
Actuator:
Reaction
Wheel
ACS
Actuator:
Reaction
Wheel
Body rate
Body rotation
Wheel
speed
+
τ
e
Q
dQ
Sensor 3:
Rate Gyro
Sensor 3:
Rate Gyro
Sensor 1:
Electronic Compass
Sensor 1:
Electronic Compass
Active
Balancing
System
Active
Balancing
System
Chart: 9
Structures Design
Chart: 10
Sparse-aperture Optics/Control
System (SOCS) Framework
PSF
PSF
X Analyze Optics Performance Requirements
X Analyze Optics Performance Requirements
Y Determine Array Configuration
Y Determine Array Configuration
Z Determine Tolerable Beam
Combining Errors
Z Determine Tolerable Beam
Combining Errors
[ Design/Build
Sub-Aperture
Telescope
[ Design/Build
Sub-Aperture
Telescope
\ Design
Relay Optics
\ Design
Relay Optics
_ Develop Wavefront Sensors,Controllers
_ Develop Wavefront Sensors,Controllers
^ Design, Analyze, Build Structures
^ Design, Analyze, Build Structures
Track
WFE
Budget
θr
θr
EE
EE
SR
SR
ACS
ACS
SNR
SNR
FOV
FOV
MTF
MTF
L
L
D
D
# of Aperture
# of Aperture
Piston
Piston
Tilt/Tip
Tilt/Tip
Pupil
mapping
Pupil
mapping
# Reflection
# Reflection
Geometry
Geometry
# Control Channel
# Control Channel
Beam
Combiner
Beam
Combiner
A
s
s
e
m
bly
/
A
l
ignment Errors
A
s
s
e
m
bly
/
A
l
ignment Errors
RMS WF Error Budget Tree
r
Focal_1
Focal_1
M=d/D
M=d/D
FSM
FSM
FMs
FMs
ODLs
ODLs
Structure Vibration
Structure Vibration
]Design
CCD System
]Design
CCD System
Bea
m
Combini
nng
Errors
Bea
m
Combini
nng
Errors
Su
b Aperture R
M
S W
F
E
Su
b Aperture R
M
S W
F
E
Optical Co
mpo
n
ents Errors
Optical Co
mpo
n
ents Errors
Residual Optics Desig
n
W
F
E
Residual Optics Desig
n
W
F
E
Allowable
misalignment
Allowable
misalignment
Chart: 11
Determination of Array Configuration
A (x,y) abs( )^2 S (x,y)
Amplitude Spread Function Point Spread Function (PSF)
P (ξ,ζ) Auto-correlation H (ξ,ζ)
Complex Pupil Function Optical Transfer Function (OTF)
Angular Resolution,
Strehl Ratio Requirement
Angular Resolution,
Strehl Ratio Requirement
Find suitable PSF, MTF
Find suitable PSF, MTF
Determine the
corresponding L, D
Determine the
corresponding L, D
Chart: 12
Impact of [L D] on Resolution
Final Selection for the ARGOS testbed
L=0.19185 m
D=0.210 m (8 inch COTS telescope)
Final Selection for the ARGOS testbed
L=0.19185 m
D=0.210 m (8 inch COTS telescope)
Chart: 13
Phasing Error Analysis –
Piston(OPD) Error
I ∝
πD(1 + cos( r))
λ
2
J
1
(πD sin r / λ )
πD sin r / λ
2
e
j2π ( L
k
r / λ ) cos( δ
k
?θ )
e
jφ
k
k =1
n
∑
2
- Menneson’s Equation
- simplified
-4 -2 0 2
x 10
-6
0.5
1
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
1.2
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
1.2
1.4
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
1.2
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
1.2
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
1.2
-4 -2 0 2
x 10
-6
0.2
0.4
0.6
0.8
1
1.2
Golay w/o OPD
Golay w/ OPD
Monolithic
I
Array
=3+2cos( 3cos(π/6+θ)2πLr/λ+φ
12
)
+2cos( 3cos(π/6?θ)2πLr/λ+φ
13
)+2cos( 3sin(θ)2πLr/λ+φ
23
)
+0.2λ
-0.2λ
λ/10 was suggested
as maximum piston
(OPD) error
λ/10 was suggested
as maximum piston
(OPD) error
Chart: 14
Phasing Error Requirement –
Tilt / Pupil Mapping Error
Pupil Mapping Error :
Golden Rule of Beam Combining
D/L (Entrance Pupil) =d/l (exit pupil)
Max allowable = 12 μm
Pupil Mapping Error :
Golden Rule of Beam Combining
D/L (Entrance Pupil) =d/l (exit pupil)
Max allowable = 12 μm
FEM Tilt Error Analysis
predicts maximum
allowable: 0.35 μrad=20 μ Deg
FEM Tilt Error Analysis
predicts maximum
allowable: 0.35 μrad=20 μ Deg
Chart: 15
Magnification vs Shear Error
? Sub-aperture magnification can be tuned to maximize
allowable shear error (lateral pupil mapping error) thereby
reducing control complexity.
Chart: 16
ZEMAX, CODE-V
? Zemax is a professional ray tracing/optical design software
? Sequential, Nonsequential Ray Tracing
? Optimization of optics design
? PSF, MTF, Spot Diagram, Imaging Analysis
? Tolerancing and Sensitivity Analysis
Chart: 17
Complete WF Error Budget
Distortion
0.015
Field Curvature
0.020
Other abberations
0.013
Optical Design Errors
(Residual Design Error)
0.028
Fabrication + alignment
0.015
Thermal
0.01
Collimator
0.0009
Subtelescope w/ Collimator
0.017
Fabrication
0.015
Thermal
0.01
Alignment
0.010
Primary
0.021
Fabrication
0.015
Thermal
0.01
Alignment
0.010
Secondary
0.017
Beam Combiner
Manufacturing Error
0.027
Piston(Phase) Error
0.028
Tilt/Tip Error
0.016
Pupil Mapping Error
0.015
Magnification Error
0.015
Sensor Error
0.010
Actuator Error
0.01
Beam Combining Error
0.041
Inter-subtelescope alignment
0.015
Pointing/Focus
0.01
Assembly Deformation
0.01
FSM
ODL
FM @ BC
Fold Mirrors Alignment
0.01
Assembly/Alignment
0.029
Thermal Deformation
0.02
Jitter/Drift (Image)
0.015
Jitter/Drift (Pupil)
0.015
Gravity Release Error
0.010
Environmental Error
0.0309
Total Wavefront Error
0.0727 (total RMS) < 0.075
Strehl Ratio =
2
(2 / )
e
πσ λ?
,σ= RMS Wavefront error.
Chart: 18
Optical Cost Models
? Investigate economical viability of modular optics
given performance constraints
? Focus on monolithic Cassegrain telescopes versus
Golay-3 design
? Use real data and experience from ARGOS
δk
Lk
B
Dk
lk
b
dk
sub-telescope plane
(input p up il)
combiner plane
(exit pupil)
foca l p la ne
(image pupil)
object
k-th aperture
beam
combiner
relay
optics
Chart: 19
Literature Search for Cost Models
Kahan, Targrove, “Cost modeling of large
spaceborne optical systems”, SPIE, Kona, 1998
Humphries, Reddish, Walshaw,”Cost scaling laws
and their origin: design strategy for an optical array
telescope”, IAU, 1984
Meinel, “Cost-scaling laws applicable to very large
optical telescopes”, SPIE, 1979
Meinel’s law:
2.58
0.37 [M$] (1980)SD=?
Chart: 20
Small Amateur Telescopes
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
0
0.5
1
1.5
2
2.5
3
x 10
4
Telescope Diameter D [m]
Telesco
pe Purch
a
se Cost C [20
0
1
$
]
Telescope Cost CER (Aperture): C=28917*D
2.76
? Priced various amateur
telescopes
–DHQ f/5
– DHQ f/4.5
– D Truss f/5
– Obsession f/4.5
– Celestron G-f/10
? Fit power law
? Exponent surprisingly
similar to Meinel’s Law
2.76
28917CD=
Chart: 21
Professional Telescope OTA cost
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
0
0.5
1
1.5
2
2.5
3
3.5
4
x 10
5
Aperture Diameter D [m]
OTA Cost
[2
001 $
]
Ritchey-Chretien
Classical Cassegrain
Company: Optical Guidance Systems
(http:www.opticalguidancesystems.com)
CERs for
Ritchey-Chretien
Classical Cassegrain
Remarkable Result:
virtually identical
power law across
completely different
product lines.
2.80
376000
RC
CD=?
2.75
322840
CC
CD=?
Chart: 22
ACS Mass and Cost
? Reaction wheel mass scales w/
momentum capacity
? Reaction wheels dominate
ACS mass
? ACS cost is function of mass
? Scale using ARGOS ACS mass
and cost
? Inertia depends on sub-aperture
masses and geometry
? Assumed 1.5 deg/sec slew rate
0 10 20 30 40 50 60 70
0
2
4
6
8
10
12
14
Mass [Kg]
Momentum Capacity [Nms]
Ball, Honeywell, and Ithaco RWAs [Kg = 2.49 Nms
0.41
]]
Kg = 2.49Nms
0.41
0.8
$
ACS o ACS
cKg=
Chart: 23
Sub-System Cost Tables
Chart: 24
Sub-System Cost Tables
Chart: 25
Sub-System Cost Tables
Chart: 26
Labor Cost Table
Sub-System Yearly
Rate Spring Summer Fall Spring Total Total Recurring
Passive Optics Soon-Jo Chung $70,000 200 200 200 200 800 $61,833 $15,458
Janaki Wickrema $50,000 260 0 260 130 650 $35,885 $7,177
Erik Iglesias $50,000 260 360 260 130 1010 $55,760 $7,177
David Ngo $50,000 260 360 260 130 1010 $55,760 $7,177
Active Optics Soon-Jo Chung $70,000 150 160 150 150 610 $47,148 $11,594
Abran Alaniz $50,000 260 360 260 130 1010 $55,760 $7,177
Praxedis Flores III $50,000 260 0 260 130 650 $35,885 $7,177
ACS Carl Blaurock $70,000 0 0 78 78 156 $12,058 $6,029
Ayanna Samuels $50,000 260 0 260 130 650 $35,885 $7,177
Susan Kim $50,000 260 0 260 130 650 $35,885 $7,177
Paul Wooster $50,000 260 0 260 130 650 $35,885 $7,177
Structures Marc dos Santos $50,000 260 0 260 130 650 $35,885 $7,177
David LoBosco $50,000 260 0 260 130 650 $35,885 $7,177
PAS Raymond Sedwick $70,000 104 96 104 104 408 $31,535 $8,038
Soon-Jo Chung $70,000 0 0 0 104 104 $8,038 $8,038
Carolina Tortora $50,000 260 0 260 130 650 $35,885 $7,177
Christopher Rakowski $50,000 260 360 260 130 1010 $55,760 $7,177
Dustin Berkovitz $50,000 260 360 260 130 1010 $55,760 $7,177
SOC John Keesee $90,000 104 96 104 104 408 $40,545 $10,335
Eric Coulter $50,000 260 0 260 130 650 $35,885 $7,177
Daniel Kwon/Lisa Girerd $50,000 260 0 260 130 650 $35,885 $7,177
Management Paul Bauer $70,000 104 96 104 104 408 $31,535 $8,038
David Miller $90,000 104 48 104 104 360 $35,775 $10,335
Raymond Sedwick $70,000 26 0 26 26 78 $6,029 $2,010
John Keesee $90,000 26 0 26 26 78 $7,751 $2,584
Total $919,903 $190,115
ARGOSHours
EB/OHD Wrap
2.12
Student
$50,000
Staff
$70,000
Management
$90,000
Chart: 27
Labor Cost Table
Sub-System
mult Total Recurring mult Total Recurring mult Total Recurring
Passive Optics 1 $209,240 $36,990 0.3 $62,772 $11,096.88 1 $209,240 $36,990
Active Optics 1 $138,794 $25,948 0.3 $41,638 $7,784.38 1 $138,794 $25,948
ACS 1 $119,714 $27,560 1 $119,714 $27,560.00 1 $119,714 $27,560
Structures 1 $71,771 $14,354 0.6 $43,063 $8,612.50 1 $71,771 $14,354
PAS 1 $186,980 $37,608 1 $186,980 $37,607.92 1 $186,980 $37,608
SOC 1 $112,316 $24,689 1 $112,316 $24,689.17 1 $112,316 $24,689
Management 1 $81,090 $22,967 1 $81,090 $22,966.67 1 $81,090 $22,967
Total $919,903 $190,115 $647,572 $140,318 $919,903 $190,115
Sub-System
mult Total Recurring mult Total Recurring mult Total Recurring
Passive Optics 1.5 $313,859 $55,484 2 $418,479 $73,979 2.5 $523,099 $92,474
Active Optics 2 $277,588 $51,896 3 $416,381 $77,844 4 $555,175 $103,792
ACS 1 $119,714 $27,560 1 $119,714 $27,560 1 $119,714 $27,560
Structures 2 $143,542 $28,708 3 $215,313 $43,063 4 $287,083 $57,417
PAS 1 $186,980 $37,608 1 $186,980 $37,608 1 $186,980 $37,608
SOC 1 $112,316 $24,689 1 $112,316 $24,689 1 $112,316 $24,689
Management 1 $81,090 $22,967 1 $81,090 $22,967 1 $81,090 $22,967
Total $1,235,088 $248,912 $1,550,272 $307,709 $1,865,456 $366,506
ARGOS Monolith Golay-3
Golay-6 Golay-9 Golay-12
Chart: 28
Golay System Costs
?Optimum Golayis
D
eff
-dependent
? Labor moves
Golay benefits to
larger D
eff
? Golay’s sacrifice
Encircled Energy
EE=83.5% EE=26.4% EE=9.3% EE=3.6%
EE=2.2%
Chart: 29
Compact Golay-3
? Reduces side-lobes, improves EE,
improves fill factor (SNR)
? Sacrifices cost savings
? Adding bus & relay optics costs
defines Golay-3 vs. monolith
breakpoint
*
ARGOS
L=1.2xD L=D (Golay) L=0.8xD
*
ARGOS
Chart: 30
Compact Hex Arrays
EE=62% EE=50% EE=40% EE=31% EE=23%
Deff=0.42m
Deff=0.64m
Deff=1.79m
Compact Golay-3
Compact Golay-6
Compact Golay-9
Compact Golay-12
Compact Hex
MonolithGol
a
y
-
3
Gol
a
y
-
6
Gol
a
y
-
9
Gol
a
y
-
1
2
?Larger D
eff
favors higher
order Golays
? Golay-3 & Hex compact
better than higher order
Golays
? Compactness limited by sub-
aperture interference
? Hex is not as cost-efficient at
providing full uv-coverage as
Golay
Equal D
eff
(angular resolution)