Post on 22-Apr-2020
Shields-1, a CubeSat with a radiation
shielding research payload
D. Laurence Thomsen III1, Wousik Kim2, Nathanael A. Miller3, Amanda M. Cutright3, and James W. Cutler4
(1) NASA Langley Research Center, Advanced Materials and Processing Branch, 6A West Taylor Street, MS 226, Hampton, VA 23681.
(2) Jet Propulsion Laboratory, Mission Environments Group, 4800 Oak Grove Drive, MS 122-107, Pasadena, CA 91109-8099.
(3) NASA Langley Research Center, Mechanical Systems Branch, 1 North Dryden Street, MS 432, Hampton, Virginia 23681
(4) University of Michigan, Department of Aerospace Engineering 1320 Beal Avenue, 3013 FXB Building, Ann Arbor, MI 48109-2140.
Agenda
I. Materials
Advanced Materials and Processing Branch, NASA Langley Research Center
II. Shields-1:
1. Mission Overview
2. Experiment Overview
3. Space Environment
4. Dosimetry
5. Radiation Shielding Experiment
III. Conclusion
IV. Collaborators
V. Acknowledgements
VI. Questions
Materials
Advanced Materials and Processing Branch
• Extreme-Use Temperature Composites • Radiation Shielding • Refractory Ceramics • Materials on The International Space Station Experiment (MISSE)
Materials for Extreme Environments
MISSE deployment on ISS, containing NASA LaRC Materials
Advanced Materials, Polyimide Resins and
Composites
Maturation of PETI-5: Requirements Driven High Performance Adhesive and Composite Matrix Resin
PETI-5/IM7 Skin Stringer Panel (6 ft x 10 ft)
•About 20,000 pounds of IM7/PETI-5
unidirectional tape prepared in the
HSR program
• Performance at 350°F for 60,000 hrs
(previously unattainable)
• Technology patented and
licensed to 4 companies
NASA LARC Advanced Materials R&D
Polyimide Based R&D 100 Winners
2005 PETI-330 High Temperature Resin
2001 TEEK Polyimide Foam
2000 Macro Fiber Composite Actuators
2000 Atomic Oxygen Resistant Polymers
1996 LaRC -SI
Methods of Making Atomic Number Z-grade
Radiation Shielding
Titanium 6-4 Tantalum Copper
Schematic of Z-grade Lay-up with Fiber Metal Laminate
Ta on IM-7 Carbon Fiber (CF) Fabric SEM cross-sectional image
Thickness ~196 - 210mm
Ta
CF
U.S. Patent 8,661,653, 4 March 2014, “Methods of Making Z-Shielding.” D.L. Thomsen III, R.J. Cano, B.J. Jensen, S.J. Hales, and J.A. Alexa.
2 mil Ta coating on Al 6061
5 cm
Radio Frequency (RF) Plasma Spray Ta on Aluminum (Al)
Ta RF Plasma Spray Coated Al Radiation Shielding
2 mil Ta coating on Al 6061
Ta Ta
Al
Al
• Disappearance of pores, when coated on Al sheet. • RF Plasma Spray process is variable
2 mil Ta coating on Al 6061
5 cm
RF Plasma Spray Ta on Aluminum (Al)
Rf Plasma Spray Ta Foil Properties
1. Maissel and Glang, Handbook of Thin Film Technology, McGraw Hill Publishing, 1970.
Tantalum Material Properties Density (g/cm3) Volume Resistivity (mohms-cm)
Crystal Structure
Reference
Rf Plasma Spray Ta (Z=73) 16.02 +/- 0.02 49 +/- 6 bcc
Bulk Ta 16.6 13 bcc 1.
Thin Film Ta 15.6 25-50 bcc 1.
Radio Frequency Plasma Spray Facility
NASA-LaRC RF Plasma Spray Facility 1 Rotary water
cooling coupler Sting Rotat ional/
Translat ional Shaft
2"/ sec.
Plasma Spray
Chamber
Powder
Injector
Probe
RF Torch
Mandrel
120 RPM
Melted Part icles
2
Chamber Interior
RF Torch
Mandrel
3
Plasma
Plume
4 Metal Deposition on Rotating Substrate
Equipment Schematic
Metal
Deposit
Shields-1
Shields-1 CubeSat Mission Overview
Proton Belt Electron Belt
Shields-1 focuses on enabling future research and commercial space technology mission by reducing the harmful effects of harsh radiation environments to spacecraft. This is accomplished by raising the TRL of Atomic Number (Z) grade radiation shielding technologies.
Mission features: - Radiation Shielding
Experiment - Secondary small
satellite payload mission planned for Geostationary Transfer Orbit (GTO)
- Charge Dissipation Film - Vault enables use of
COTS components
Total ionizing dose (TID) environment: Shielddose-2 Calc: 2.70 krad/yr , 3 g/cm2 Al
Shields-1 Experiment Overview
Shields-1 3U CubeSat Schematic
Graphical Concept of the Dose Depth Curve (DDC)
demonstrating Shields-1 ability to provide data to validate atomic
number (Z) grade radiation shielding solutions Charge Dissipation Film
Luna Innovations , NASA STTR Program
Shields-1 provides performance data of multiple radiation shielding materials that ultimately enable the success of future missions
Areal density
TID
2 mil Ta coating on Al 6061
5 cm
RF Plasma Spray Ta on Al
RF Plasma Spray Ta Carbon Fiber Laminate
Space Environment Comparison: GTO and P-LEO
Proton Fluence, 1 year
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
1.E+11
1.E+12
1.E+13
1.E+14
1.E+15
1.E+16
0.01 0.1 1 10
Log
Inte
gral
Ele
ctro
n F
lue
nce
(cm
-2)
Log Energy (MeV)
GTO
P-LEO
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
1.E+11
1.E+12
1.E+13
1.E+14
1.E+15
1.E+16
0.1 1 10 100 1000
Log
Inte
gral
Pro
ton
Flu
en
ce (
cm-2
)
Log Energy (MeV)
GTO
P-LEO
Electron Fluence, 1 year
1.E+08
1.E+09
1.E+10
0.1 1 10 100 1000
Log
Inte
gral
Pro
ton
Flu
en
ce (
cm-2
)
Log Energy (MeV)
Shielded GTO,Al 3 g/cm2
Shielded P-LEO,Al 0.5 g/cm2
SPENVIS: AP8min-AE8 Max Model for GTO and Polar LEO, ELaNa III Satellite Environment
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
1.E+11
0.01 0.1 1 10
Log
Inte
gral
Ele
ctro
n F
lue
nce
(cm
-2)
Log Energy (MeV)
Shielded GTO,Al 3 g/cm2
Shielded P-LEO,Al 0.5 g/cm2
Total Ionizing Dose (TID) Environment
GTO:
• GTO Orbit: 23o inclination, 37,500 km apogee, 240 km perigee
• Shields-1 Initial Planning Environment
• Total ionizing dose (TID) environment: Shieldose-2 calculation2:
2.7 kRad/yr , 3 g/cm2 Al
Polar- LEO:
• Orbit: 102o inclination, 775 km apogee, 458 km perigee
• ELaNa III1 CubeSat environment: AUBIESAT-1, RAX-2, DICE, Explorer,
M-Cubed/COVE.
• TID environment Shieldose-2 calculation2: 5.0 kRad/yr total dose,
0.5 g/cm2 Al
1. http://www.nasa.gov/pdf/627975main_65121-2011-CA000-NPP_CubeSat_Factsheet_FINAL.pdf 2. SPENVIS, https://www.spenvis.oma.be/, Shieldose-2 calculation, AP8min-AE8 Max Model Environment.
GTO Trapped Proton Challenges: SEUs
• CRRES1 experimentally determined single event upset (SEU) rate for most sensitive electronic devices: 10-3 bit-1 / day in Proton Belt (L<2.5) and 10-5-6 10-3 bit-1 / day in regions outside of proton belt (L>2.5).
• 10-3 bit-1 / day in Proton Belt (L<2.5) is two orders of magnitude higher SEU rate than recommended2-3 for COTS.
1. E.G. Mullen and K.P. Ray, “Microelectronics Effects as Seen on CRRES”, Adv. Space Res. Vol. 14, No. 10, pp. 797- 807, 1994.
2. J.R. Wertz and W.J. Larson, Space Mission Analysis and Design, 3rd Edition. 2007, Microcosm Press, p. 976.
3. NASA Preferred Reliability Practices, PD-ED-1258. “Space Radiation Effects on Electronic Components in Low-Earth Orbit”, April 1996. p. 7.
0
Dosimetry and Data Collection Plan
Radiation shielding sample RADFET, dosimeter backing
(Side-view)
FOV deg
radius
Dosimetry sample geometry options with larger areal density backing than sample.
Past Space Dosimeter Experiments: GOES-7 (1978): CRRES (1990) LDEF (1991) METEOSAT-3(1991) Van Allen Belt Storm Probe (2013)
To capture Trapped Proton and Electron belt Doses, greater and less than L shell ~2.5
FOV = field of view
1. Approximate half-spherical shell
(Side-view)
2. Approximate Infinite Slab
Proton Belt region
Electron Belt region
L shell ~ 2.5
1
10
100
1000
10000
100000
1000000
0 1 2 3
Log
Do
se in
Si (
Rad
/ye
ar)
Areal Density (g/cm2)
TrappedProtons
TrappedElectrons
Bremsstrahlung
Shieldose-2 model center of Al Spheres dose divided by 2 for half-sphere sample geometry.
Radiation Shielding Experiment
2 mil Ta coating on Al 6061
Ta 5 cm
1. RF Plasma Spray Ta on Al
2. RF Plasma Spray Ta Carbon Fiber Laminate
Experimental Samples Baseline Samples
1. RF Plasma Spray Tantalum Foil
2. Tantalum Sheet
3. Carbon Fiber Laminate
4. Aluminum
4 samples: 0.5, 1.3, 2, and 3 g/cm2
• 4 to 5 Samples planned for each material (0.5 g/cm2 – 3 g/cm2) • Build experimental dose depth curves for proton belt and electron belt regions • Compare to trapped belt models
Al half-sphere geometry baseline dose depth curve
Conclusion
• RF plasma spray coatings enable new forms of Z-grading.
• The GTO trapped proton and electron belt environments offer
the opportunity to test radiation shielding materials in more
than one environment.
• Z-grading is not limited to electron dominant environments. Z-
grading will be increasingly important with benchmarking the
state of the art in passive radiation shielding.
Collaborators
• Shields-1: Mr. Victor Stewart (LaRC), Mr. Mark Jones (LaRC),
Dr. Bill Seufzer (LaRC), Mr. Stephen Casey (LaRC), Mr. Kevin
Vipavetz, (LaRC), Mr. Salvatore Scola (LaRC), Mr. David Way
(LaRC).
• Materials Research and Development: Mr. Roberto Cano
(LaRC), Dr. Brian Jensen (LaRC), Dr. Steven Hales (LaRC), and
Mr. Joel Alexa (AMA).
• Radiation Physics: Dr. Sheila Thibeault (LaRC).
• Modeling: Ms. Suzanne Maddock (Science Systems and
Applications, Inc.), Dr. Francis Badavi (Christopher Newport
University), and Dr. Martha Clowdsley (LaRC).
• Scanning Electron Microscopy: Mr. James Baughman (AMA).
• Density Measurements: Ms. Helen Herring (AMA).
Acknowledgements
• Dr. Henry Garrett, JPL
• Dr. Insoo Jun, JPL
• Dr. Cheryl Marshall, GSFC
• Dr. Robert Bryant, LaRC
• Dr. Steven Walker, Old Dominion University
• Mr. Adam Goff, Luna Innovations