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1
Mission Goals
Brandi Casey (Project Manager)
2
What is it?
TREADS NanoSat (TREADS-N)�Testbed for Responsive Experiments And
Demonstrations in Space (TREADS) �
• TREADS is a 'full-service' technology demonstration and science gathering platform
• TREADS-N is a member of the TREADS family of testbeds that provides:– Pointing capabilities
– Increased power generation over TREADS-H
– Greater downlink capacity than TREADS-H
3
Mission Goals
• The TREADS-N will compliment the TREADS family by providing a free-flyer platform for instrument testing that will provide extra utilities for customers requiring extra functionality such as more precise pointing, improved data rates, or extra power.
– “Risk-reduction” for large projects
– “First to market” for commercial products
– “Essential science” for principal investigators
4
Our Focus
• Your technology is the primary payload
• In-situ demonstrations and risk-reduction– Increase TRL
– Baseline science/tactical capabilities
• 'Technology slots' available for 1 to 6 instruments– Several 'customers' per flight (up to 80kg total)�
– Don't have to be chosen (i.e. prime/sub)�
– Don't need a dedicated s/c – 'per-slot' basis
• You decide when you fly! Self-Manifest SM
• SBIR Phase III Demonstration Platform
5
Configurations
• 3 configurations to keep costs low and perform to customer specifications– Hosted Platform
• Low Cost
• Board-Level Electronics
– CubeSat Platform
– Nanosat Platform• Large Payload Size
• Pointing Ability
6
Today's Focus• Nanosat Platform (riding within RideShare
Adapter (RSA) or ESPA)�– A testing structure for board-level electronics and
stand-alone components
– Specific components chosen for possible future flight
7
Description of TREADS-N
• Description– Free-flying satellite
– Released from the RSA or the Evolved Expendable Launch Vehicle (EELV) Secondary Payload Adapter (ESPA) �
• 15’ lightband adapter
– Designed for specific payloads
• Mission/Orbit Envelope– Falcon 1 launch vehicle
– Test orbits from equatorial to polar
– Test altitudes from 300 km to 700 km
– 1 year mission
8
Milestones• TREADS-H—CDR Dec. 2008
• TREADS-N—CoDR Feb. 2009
• Worked towards PDR design from Feb–April 2009
• TREADS-N—PDR
• Space Grant Symposium—TREADS-N
• First week of May a PDR Design Delivery of TREADS-N
• Personalized Projects from RedfineTechnologies
9
Schedule Overview
• Spring work 2009: TREADS Nanosat(TREADS-N).
• TREADS Hosted seeking phase III approval for SBIR.
• Redefine seeking launch opportunity in 2010.
• Redefine seeking more customers to further progress TREADS-C, TREADS-H and TREADS-N.
10
Brandi Casey
(Project Manager)
Andrew Bath(Systems Lead)
Jay Trojan(ADCS Lead)
Nate Bailey(Structures Lead)
Sreyasi Vinjamuri(Comm Lead)
Malcolm Young(Systems)
Brian Macumber(Structures)
Robin Blenden(Comm.)
Curtis Miller(Thermal Lead)
Brian Sanders
Research Coordinator
Jay Trojan(Power Lead)
Redefine Technologies
Space Grant
Steve WichmanCEO, Redefine Technologies
Software Design
11
DUT and Payload Overview
Brandi Casey (Project Manager)
12
• Device-Under-Test (DUT) �
• Various DUT interfaces– 6U, 3U, PC104, Space104
– cPCI, 1553, SpaceWire, RS422, etc
– Exterior connection for components
• Radiation resistant test controller & flight computer– exercise DUT and record data
• Communication link– Downlink results, uplink new
configurations
• Lifetime� Nominal: 12 months
� Extended: 3 years
Supporting a DUT
13
Systems
Presented by:
Andrew Bath
Malcolm Young
14
System Objectives
Ref Description
0.OBJ.01 The TREADS-N platform will provide payloads a LEO space environment in which to test and verify their hardware for space applications.
0.OBJ.02 The TREADS-N will downlink data to a control center via a ground station.
0.OBJ.03 The TREADS-N will accommodate various numbers and types of customer's payloads.
0.OBJ.04 This TREADS-N will be designed to reduce recurring engineering costs.
0.OBJ.05 The TREADS-N will be designed to integrate to the RSA and ESPA payload adapter asoutlined in their respective user's documents.
0.OBJ.06 The TREADS-N will be designed to keep its utilities operable for greater than 1 year.
0.OBJ.07 The TREADS-N will provide 3-axis pointing.
0.OBJ.08 The TREADS-N will provide more power, more mass, and more data throughput than the TREADS hosted solution to payloads.
0.OBJ.09 The TREADS-N will use parts of the TREADS-H to reduce design complexity and allow interchangeability of parts.
0.OBJ.10 The control center will work with the customer to make configuration changes to DUT software and DUT manager software during the mission.
15
System Requirements• TREADS-N shall be sized such that two will fit into the ESPA envelope
with a 15" lightband between them
• Avionics shall fit into the standardized boxes designed for TREADS-H
• Shall have as large of an optical hole as possible in one of the sides
• Shall have >75W available for payloads 100% of the time
• Shall have >40kg mass available for payloads
• Shall have >180 MB/72 hrs download capability
• Shall have >3 MB/72 hrs upload capability
• Shall have three ground stations will be baselined (PR, HI and CO)
• Shall have pointing accuracy to +/- 1 arcsec, attitude knowledge to within +/- 0.1 arcsec
� note: may require RTOS and floating point capability on flight computer
• Shall use SIL batteries
• Shall use ClydeSpace solar panels
16
Baseline Payloads
• Space Micro Inc Transponders– The Space Micro Transponders are microwave communication
transponders built to withstand the rigors of the space environment.
These transponders may be modified to increase the radiation
mitigation abilities, including Total Dose, SEU, and SEL prevention.
• Optical Tube– The Optical tube specs are being used as the Orion 150mm Mak-Cass
Telescope Tube. This is just a baseline design to further understand
the requirements of a similar telescope tube. In addition to the Orion
telescope tube, there will be a camera box on the top of the tube,
something like a 3U size CCD with a second board to support it.
• Pyxis GPS Reciever– “The Pyxis receiver is available as a stand-alone receiver or 3U cPCI
board LEO Precision Orbit Determination receiver (Pyxis-POD), as a
Radio Occultation and POD GNSS Receiver (Pyxis-RO), and as a GEO
Precision Orbit Determination receiver (Pyxis-GEO).”
17
Baseline Payloads
• Space Micro MicroRad 100 Dosimeter– "The MicroRAD 100™ is a low power, high performance space dosimeter
solution that meets the challenges of space and satellite harsh environment
platforms”
• Redefine CMDRS Technology Demonstration Kit– 1x3U card consuming approximately 10W.
• SIRF Flight Experiment– 6U Card consuming approximately 10W
18
System Layout
• Physical System Layout:• Light band adaptor (stacked
configuration)
• Skinned isogrid design
• Directional antenna
• Deployed solar arrays
• Holes for telescope and star trackers
19
Physical Layout
Avionics Box
DUT Test Box
Sil Intellipack
33.6V
Sola
r Pan
el A
rray
Torque Rods/
Reaction Wheels
Antenna
Attitude Sensors
GSE
Activation Signal
Space Micro Transponder
Imag
ing
Paylo
ad
Pyxis GPSSpace Micro
MicroRad 100
20
Electrical LayoutTwo Main Boxes
Avionics DUT Test Box
Backpla
ne
Backpla
ne
PCU
Flight Computer
(RPB MRA)
Radio
(MHX 2420)
DUT Manager
(PROTON 200K)
DUTs
DUTs
Coaxial Antenna
RS-232
5V
RS-232 to GSE
RS-422
I2C
RS-485 to Magnetometer
GPIO
5V
5V
3.3V
12V
28V
RS-42233.6V
Battery
RS-422
Battery
Solar
Panel
3.3V
12V
5V
5V
RS-422
3.3V
12V
5V
5V
RS-422
RS-485
3.3V
12V
5V
5V
RS-422
RS-485
RS-485
RS-422 (x8)
CPCI (x2)
CPCI
CPCI
3.3V
Torque Rod Driver5V
I^2 (sensors)
cPCI
To Attitude Sensors
Activation Signal
28V
28V
28V
External DUTS
Torque
Rods
21
Orbital Environment
Mission Duration
Dependant on Risks of
Hardware Failure
1 Year+ Mission
22
Subsystem Overview - CDHDesign
• Backplane for data and power transmission inside boxes
• Proton 200k for DUT manager
• RPB MRA for flight computer
• cPCI, RS-485, RS-422, and GPIO support for DUTS, both internal and external
Current Progress• CDH system is being ported over from TREADS-H design. Currently
no personnel allocated to improve the current design
23
Design• S-Band Antenna/Radio
• Extremely high data rate requirements
• Supporting optical payload which takes 6Mb pictures
Current Progress• Data transmission rates being investigated
• Link Budgets being created to ensure links
Subsystem Overview - COM
Hawaii
Puerto Rico
Boulder
24
Subsystem Overview - THMDesign
• Getting a preliminary idea thermal environment
• Analyzing un-mitigated temperatures in several target orbits in two different software packages
� Thermal desktop
� MATLAB
Current Progress• Several orbits analyzed and characterized
• Alodine coating required
• White paint on payloads
• Non thermally-conductive connections between solar arrays and structure
• Current models indicate no need for more thermal mitigation
25
Subsystem Overview - ADCDesign
• Ensure pointing accuracy to +/- 1 arcsec, and attitude knowledge to within +/- 0.1 arcsec for supporting optical payload
� Torque rods
� Reaction wheels
� Sun sensor
� Magnetometer
� IMU
� Star tracker
• Provide solar panel power estimates based on pointing
Current Progress• Simulations showing jitter, reaction wheel storage/sizing
Antenna/OpticalVector
Sun Vector
y
x
z
Body axes
26
Subsystem Overview - EPSDesign
• 90 watt continuous draw allocated for system completion
• 75W allocated for PDR level
• 200W solar array to support this
� Rigid 90 degree deployment
• - Low complexity
• - Simple deployment mechanism
• - Low cost
• Sil Intellipack 33.6V battery pack
• Provide +/-28V, 12V, 5V, and 3.3V to satellite
Current progress• Significant work done on power modes
• Battery and solar arrays sized based on pointing requirements
Solar Array Petal Design
27
Power BudgetT
op
-do
wn
Bo
tto
m-u
p
Phase AO SCR PDR CDR PQR Flight
Margin 50% 35% 25% 15% 5% 0%
Design Power 50.00 W 65.00 W 75.00 W 85.00 W 95.00 W 100.00 W
STR THM ADC EPS COM CDH Science TOTAL
Allocation 0% 4% 17% 15% 7% 25% 32% 100%
Allocated Power 0.00 W 3.00 W 12.75 W 11.25 W 5.25 W 18.75 W 24.00 W 75.00 W
STR THM ADC EPS COM CDH Science TOTAL
Under Allocation 0.00 W 0.18 W 0.10 W 0.25 W 0.54 W 1.50 W 0.54 W 3.12 W
by 0% 6% 1% 2% 10% 8% 2% 4.16%
STR THM ADC EPS COM CDH Science TOTAL
Contingency Power 0.00 W 2.82 W 12.65 W 11.00 W 4.71 W 17.25 W 23.46 W 71.88 W
Contingency 0% 15% 10% 10% 10% 15% 10% 11%
Average Power 0.00 W 2.45 W 11.50 W 10.00 W 4.28 W 15.00 W 21.33 W 64.55 W
Peak Power 0.00 W 7.35 W 23.50 W 10.00 W 25.66 W 15.00 W 66.05 W 147.56 W
PHASED AVERAGE POWER ALLOCATION
SUBSYSTEM ALLOCATION
COMPARISON BETWEEN ESTIMATION AND ALLOCATION
CURRENT SUBSYSTEM ESTIMATE
28
Mass BudgetT
op
-do
wn
Bo
tto
m-u
p
PHASED MASS ALLOCATION
SUBSYSTEM ALLOCATION
COMPARISON BETWEEN ESTIMATE AND ALLOCATION
CURRENT SUBSYSTEM ESTIMATE
Phase AO SCR PDR CDR PQR Flight
Margin 50% 35% 25% 15% 5% 0%
Design Mass 45.00 kg 58.50 kg 67.50 kg 76.50 kg 85.50 kg 90.00 kg
STR THM ADC EPS COM CDH Science TOTAL
Allocation 31.8% 3.3% 14.3% 20.4% 2.00% 8.2% 20.0% 100.0%
Allocated Mass 21.47 kg 2.23 kg 9.65 kg 13.77 kg 1.35 kg 5.54 kg 13.50 kg 67.50 kg
STR THM ADC EPS COM CDH Science TOTAL
Under Allocation 1.28 kg 0.13 kg 0.53 kg 0.57 kg 0.10 kg 0.31 kg 1.07 kg 4.00 kg
by 6% 6% 6% 4% 8% 6% 8% 5.92%
STR THM ADC EPS COM CDH Science TOTAL
Contingency Mass 20.18 kg 2.10 kg 9.12 kg 13.20 kg 1.25 kg 5.23 kg 12.43 kg 63.50 kg
Contingency 5% 5% 10% 10% 10% 10% 10% 8%
Estimation 19.22 kg 2.00 kg 8.29 kg 12.00 kg 1.14 kg 4.75 kg 11.30 kg 58.70 kg
29
Budget Conclusions
Power
•Peak power (All payloads operating simultaneously) is very high
•Duty cycles will insure that this situation will not happen
•Duty cycles on components reduce average orbital power draw
•This will be enforced by DUT manager and flight computer
Mass
•Currently under mass
•Payloads require far less mass than initially expected
•Structure will need further reinforcement
•This will be covered more in depth by our structures team
30
Concept of Operations
Presented by:
Malcolm Young
31
Falcon 1 User’s Guide, SpaceX
Launch TREADS-N
Operations (1 Year)
Concept of Operations
32
Ground Ops S/C Ops
LV Activities
Launch
Prim
ary
Payl
oad
Rele
ase
TR
EA
DS
-N P
ow
er O
n
Seco
ndary
Payl
oad
Rele
ase
Mis
sion S
tart
FC
Boot U
p
Sys
tem
Check
out
Exec. DUT Test(s)�
Data Downlink
Charge Batteries
Customer Feedback
Exec. Schedule
Schedule Uplink
Nominal Timeline
Nom
inal O
pera
tions
12 m
onth
s
First
Gro
und C
onta
ct
Attitu
de D
ete
rmin
ed
and A
dju
sted
33
Activities Overview
-Back orbit activities
-Not optical pointing activities
-Slews
-Take images
-Sun point
-Pass activities
-Orbit durationsLegend
34
Normal Orbit Activities
•Pointing activities grouped to increase sun point time
•Receiver always on
•DUT’s turned off prior to pass to lessen power load
•Imaging orbit
•Pass orbit
35
Risks and Mitigations
ReferenceRisk Description Likely Severity
Mitigation
1
Insufficient volume for manifested payloads
2 3
1) adjust
placement of
TREADS-N
system components
2) Design new
mounting scheme
2
Solar Arrays changing thermal environment affects efficiency
3 4
Investigate solar
array thermal
coatings
3Insufficient materials for TREADS capabilities for TREADS
customers 3 3 Manifest Forms
4 3 3 <>
Design Risks
36
Risks and Mitigations (cont)
ReferenceRisk Description Likely Severity
Mitigation
A
Primary structure failure
5 5
1) Increase panel
thickness or
Isogrid skin
2) Decrease Isogrid triangular
pattern
3) Consider other
materials
B
Data from the payloads exceeds allocated capacity
2 3
1)Data should be
dowlinked before it
reaches the storage margin
2)Acquisition of
data should be
minimized in the
next pass.
C
Lack of suitable ground station for different orbital inclinations
2 4
Investigating
multiple ground stations
Mission Risks
37
Risk Chart—System
1
A
B
2C
3
38
Conclusion and Future Work• Conclusions
• Design progress is at PDR level
• Requires further investigation:• Verify components meets thermal environment
• Advance design to meet most extreme stress loads
• Each subsystem design has to progress to CDR level
• Attitude control system is within pointing requirements
• Under mass budget
• Under power budget
• To Do (this semester)• Make all quick improvements from PDR
• Submit design documents• Updated PowerPoints
• To Do (after this semester)• Progress to CDR