living with a star space environment testbed · 2009-05-20 · exp 1 exp 2 exp n exp i/f spacecraft...

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Living With a StarLiving With a StarSpace Environment TestbedSpace Environment Testbed

Janet Barth, NASA/GSFCLWS/SET Project Scientist

AFRL Technical Interchange Meeting, Phoenix, AZ June 6, 2005

http://lws-set.gsfc.nasa.gov

AFRL Technical Interchange Meeting/Space Environment Testbed, Phoenix, AZ - June 6, 2005 2

The Living With A Star (LWS) ProgramThe Living With A Star (LWS) Program

Develop the scientific understanding necessary to effectively address those aspects of the Connected Sun-Earth system

that directly affect life and society.

SCIENCE QUESTIONS

How and why does the Sun vary?

How do the Earth and other planets respond?

What are the impacts on humanity?

SET

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- Space Station- Space Exploration- High Altitude Flight- Space Utilization &

Colonization

Human Radiation Exposure

© 1998 Geoff Sobering

Impacts on Life & Society

- Global Climate Change- Surface Warming- Ozone Depletion & Recovery

Impacts on Technology

- Space Systems- Communication & Navigation- Ground Systems

Living with a Star (LWS) Program

Science Researchto Reduce Impactsof Solar Variability


SET Science OverviewSET Science Overview

Project Goal: Improve the engineering approach to accommodation and/or mitigation of the effects of solar variability on spacecraft design and to minimize space weather effects on space hardware during operations.

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Large Uncertainties in Space Environment & Effects Large Uncertainties in Space Environment & Effects Preclude Cost Effective Use of the Space EnvironmentPreclude Cost Effective Use of the Space Environment

Validated New Technologies for Use in Space Systems

Increased Performance & Reliability

More Payload Resources

Reduced Costs from Better Ground Test Protocols

Operations Enabled in Severe Environments

Space Environment & Effects Defined

Shielding Propertiesof Materials

Interference onMicroelectronics

Interference onSensors & Detectors

UnvalidatedGround Test

Protocols

SpacecraftCharging

Degradation ofMaterials


SET GoalsSET GoalsProgramProgram--Level Requirements Document, Section 1.3Level Requirements Document, Section 1.3

• Define space environment effects and mechanisms• Reduce design margins

– Increase use of space environment “tolerant” technologies– Increase the fraction of resources for payload– Reduce launch vehicle requirements– Enable routine operations above Low Earth Orbit (LEO) (above

2000 km) for LEO cost• Improve design and operations guidelines

– Increase system reliability in interplanetary and planetary environments

– Reduce unnecessary shutdowns– Lower the risk of anomalies– Reduce the number of operational failures

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SET Carrier ConceptSET Carrier Concept

(PIB)S/CI/F

EXPI

/F

Cmd/Tlm

Standard/Fixed InterfaceGeneric Interface

SpacecraftPower

MonitorSET

Carrier(PIB)S/CI/F

Exp 1

Exp 2

Exp n

Exp I/F

Spacecraft & LaunchOpportunity

(AF/DSX for SET-1)

Series of CarriersBuilt In-house

at GSFC

“Ready-to-Go”Card and Box

FlightInvestigations


SET Approach to ScienceSET Approach to Science& Product Development& Product Development

• Define investigation topics through community workshops– NASA, industry, universities, other government agencies– Technology users and technology providers

• Acquire investigations through NASA Research Announcements (NRAs) via standard HQ peer review process and partnerships– Space investigations

• Collect data in space to validate the performance of new technology vulnerable to the effects of the solar varying environments and instruments for LWS science missions

• Collect data in space to validate new and existing ground test protocols or mechanism models for the effects of solar variability on emerging technologies and components

– Data investigations• Improve, develop, and validate engineering environment models, tools, and

databases for reliable spacecraft design and operation• Transition results of investigations (products) to user community

– Community workshops for investigators and users– Presentations at conferences– Data and product distribution and archive

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Five Science Categories for SETFive Science Categories for SET

Program-Level Requirements Document, Section 1.3:The objectives of the SET investigations are divided into five

categories as follows:1) Characterization of the space environment in the presence of

a spacecraft;2) Definition of the mechanisms for materials’ degradation and

the performance characterization of materials designed for shielding from ionizing radiation;

3) Accommodation and/or mitigation of space environment effects for detectors and sensors;

4) Performance improvement methodology for microelectronics used in space; and,

5) Accommodation and/or mitigation of charging/discharging effects on spacecraft and spacecraft components.


Source of Flight InvestigationsSource of Flight Investigations

• 11 Flight Investigations are available at this time.• 7 from NRA-2• 4 heritage investigations from STRV-1D (SET-Path)

– Existing peer-reviewed investigations from Space Technology Research Vehicle 1D (STRV-1D) were brought to our attention.

– Spacecraft failed to downlink data after a few weeks of operation

– Evaluated investigations for application to LWS/SET goals– Requested and received approval to support 4 investigations

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Available Flight InvestigationsAvailable Flight Investigations

Performance Improvement for Microelectronics

STRV-1DOptocouplers (COTS-3)


STRV-1DSingle Event Effects Mitigation (COTS-2)


STRV-1DLinear Single Event Transients (LSET) (COTS-1b)


STRV-1DLinear Enhanced Low Dose Rate Sensitivity (ELDRS) (COTS-1a)


NRA-2Total Dose and SEU Radiation Hardness Degradation Due to the Addition of Built-In Self Test (BIST) to Mixed Signal Electronic Circuits


NRA-2Development of Space-Based Test Platform for the Characterization of Proton Effects and Enhanced Low Dose Rate Sensitivity (ELDRS) in Bipolar Junction Transistors/Arizona State

Material DegradationNRA-2Definition of the Mechanisms for On-Orbit Degradation of Variable Emissivity, Variable Absorptivity and Variable Reflectivity Materials Degradation

ShieldingNRA-2Space Flight Evaluation of the Radiation Performance of PolyRAD

Environment Characterization

NRA-2Dosimetry Intercomparison and Miniaturization (DIME)

Correlative Environment Monitor

NRA-2Energetic Particle Spectrometer for Characterizing the Environment Around the LWS-SET Spacecraft. Also referred to as a Light Particle Detector (LPD)

Correlative Environment Monitor

NRA-2Cosmic Radiation Environment Dosimetry and Charging Experiment (CREDANCE)

FOCUS AREASOURCENAME

See backup charts for details.


Flight Investigation Selection ProcessFlight Investigation Selection Process

• Science Team makes payload recommendation from pool of Candidate Flight Investigations− Evaluate space environment for Ride Opportunity− Match investigation requirements to space environment− Concurrence from Ride Opportunity

• HQ approves payload recommendation• Systems Engineer & Instrument Manager perform

accommodation assessment• Final approval for payload at Mission Confirmation

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SETSET--1 Mission Configuration1 Mission Configuration

COTS-2ELDRS

DIMEDIME ~15 inches

(38cm)

~33.0 inches

(~84cm)

~39 inches(~9.9cm)

CREDANCE

Payload Mass: 18.4 Kg with 30% reservePower: 40 Watts Maximum Orbit Average

including 30% reserve

SET-1 Investigations:• CEM: CREDANCE

(BOX)• DIME (two 3U cards)• ELDRS (3U card)• COTS-2 (3U card)


Payload for SETPayload for SET--1 Mission1 Mission

• CREDANCE– Cosmic Radiation Environment Dosimetry and Charging Experiment– PI: Clive Dyer, QinetiQ/UK– Box Investigation

• DIME– Dosimetry Intercomparison and Miniaturization– PI: Peter McNulty, Clemson University– Two 3U cards

• ELDRS– Development of Space-Based Test Platform for the Characterization of

Proton Effects and Enhanced Low Dose Rate Sensitivity (ELDRS) inBipolar Junction Transistors

– PI: Hugh Barnaby, Arizona State– One 3U card

• COTS-2– Validation of Single Event Effects Mitigation via Fault Tolerant

Methodology – PI: Robert Ecoffet, CNES/FR– One 3U Card

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Investigation DescriptionInvestigation DescriptionCosmic Radiation Environment Cosmic Radiation Environment DosimetryDosimetry and Charging and Charging

Experiment (CREDANCE)Experiment (CREDANCE)

• PI: Dr. Clive Dyer, QinetiQ/UK• Science Category: Correlative Environment Monitor (CEM)• Objectives

– Characterize the energetic space radiation environment and its interactions with spacecraft

– Provide CEM data to other SET-1 experiments• Goals

– Provide data to improve radiation environment models and design tools– Demonstrate the value of a compact space weather monitor in operational

spacecraft• Measurements

– Proton flux > 40 MeV per unit solid angle– Charge deposition in large silicon diodes arranged in telescopes. Pulse height

analysis is used to obtain ion linear energy transfer (LET) spectra of heavy ions in the 100 MeV cm2/g to 25000 MeV cm2/g range

– Threshold voltage shift as a function of time to measure total ionizing dose in silicon at 2 different shielding depths

– Charging current at 3 different shielding depths which provides energetic electron flux measurements at 3 energies


Investigation Description Investigation Description DosimetryDosimetry IntercomparisonIntercomparison and Miniaturization (DIME) (1)and Miniaturization (DIME) (1)

• PI: Dr. Peter McNulty/Clemson University• Science Category: Characterization of the space environment in the

presence of a spacecraft, Performance improvement methodology for microelectronics used in space

• Objectives– Use six different COTS microdosimeters to characterize the radiation induced

total ionizing dose, displacement damage, and single event effects• Goal

– Provide data to permit appropriate dosimetry selection in future missions to characterize/resolve operational anomalies

– Validate particle transport codes by varying shielding thicknesses on RADFETs• Measurements – Next Chart

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Investigation Description Investigation Description DosimetryDosimetry IntercomparisonIntercomparison and Miniaturization (DIME) (2)and Miniaturization (DIME) (2)

• DIME Measurements– RADFET – Radiation-Sensing Field-Effect Transistor

• Threshold voltage shift as a function of time and is converted to total ionizing dose

– EPROM - Erasable Programmable Read-only Memory• Threshold voltage shift as a function of time and is converted to total

ionizing dose• Number of single event upsets as a function of time to measure rates as a

function of radiation level– SRAM - Static Random Access Memory

• Hold devices at different voltages and measure single event upsets, change in voltage at which an error occurs is converted to dose

• Number of single event upsets as a function of time to measure rates as a function of radiation level

– LET Spectrometer – Linear Energy Transfer Spectrometer• Pulse height spectra as function of time is converted to LET to measure

ions including protons– OSL Films- Optically Stimulated Luminescent Films

• Visible emission spectrum as a function of time to measure micro-dose


Investigation DescriptionInvestigation DescriptionDevelopment of SpaceDevelopment of Space--Based Test Platform for the Based Test Platform for the

Characterization of Proton Effects and Enhanced Low Dose Rate Characterization of Proton Effects and Enhanced Low Dose Rate Sensitivity (ELDRS) in Bipolar Junction Transistors (ELDRS)Sensitivity (ELDRS) in Bipolar Junction Transistors (ELDRS)

• PI: Dr. Hugh Barnaby/Arizona State University• Science Category: Performance improvement methodology for

microelectronics used in space• Objective

– Measure ELDRS (primary) and proton effects (secondary) in positive-negative-positive (PNP) bipolar junction transistors (BJTs)

• Goal– Improve understanding of the physics of ELDRS and thereby

improve/validate ground testing protocol for linear bipolar technologies and reduce design margins

• Measurement– Base and collector currents for 24 COTS BJTs as functions of the

emitter and gate voltages and time

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Investigation DescriptionInvestigation DescriptionCOTSCOTS--2: Digital Technologies2: Digital Technologies

• PI: Robert Ecoffet/CNES• Science Category: Performance improvement methodology for

microelectronics used in space• Objective

– Validate approaches to mitigate single event effects by comparing simulation techniques, performance models, and on-orbit data

– Validate mitigation of single event effects during space weatherevents

• Goal– Increase reliability of COTS technologies for space applications and

reduce design margins• Measurement

– Measure a single event effect (SEE) on COTS FPGAs, classify the event by event type, and determine if mitigation of the effect occurred without watchdog intervention


SETSET--1 Measurement Objectives1 Measurement Objectives

• Measure components of the space environment relevant to SET-1 payloads– CREDANCE

• Measure charging environment for normal background and during space weather events– CREDANCE

• Measure space radiation environments which are detrimental to space system reliability using novel dosimetry techniques– DIME

• Measure space radiation induced total ionizing dose and displacement damage on linear devices sensitive to enhanced space low dose rate effects– ELDRS

• Measure particle induced single event effects on a single event effects mitigation platform in normal backgrounds and during solar storm events– COTS-2

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Linkage of SET Flight Investigation Objectives toLinkage of SET Flight Investigation Objectives toSETSET--1 Measurements1 Measurements

XXCharacterization of the space environment

• Single Event Effects

• Total Ionizing Dose

• Displace-mentDamage

• Total Ionizing Dose

• Single Event Effects

• Space Environment

• Charging Events

SET Measurement ��

XXValidate mechanisms model

XXValidate ground test protocol

XX

Validate the performance of new technology vulnerable to the effects of the solar varying environments

COTS-2ELDRSDIMECREDANCESET-1 Science Investigations ��

Investigation Objectives*

* From Program-Level Requirements Document, Section 1.0


SETSET--1 Success Criteria1 Success CriteriaProgramProgram--Level Requirements Document, Section 2.1.2Level Requirements Document, Section 2.1.2

• Full Mission Success Criteria– The SET-1 mission payload shall deliver 95 percent of the data

obtained from experiment operations for a minimum time period ofone year and a goal of two years using resources provided by thehost spacecraft to achieve full mission success.

– Operations shall be defined as providing resources to the experiments, operating two investigations for each of the four investigation objectives.

• Minimum Mission Success Criteria– The SET-1 mission payload shall deliver 95 percent of the data

obtained from experiment operations for a minimum time period ofthree months using resources provided by the host spacecraft to achieve full mission success.

– Operations shall be defined as providing resources to the experiments, operating one investigation for each of three investigation objectives.

• Experiment success criteria are defined for each investigation (Charts 24-27).

• SET returns data from the experiments to the host spacecraft fordown-linking to the Earth.

• SET distributes SET experiment data received from the host spacecraft to the SET mission investigators.

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SET Space Environment DefinitionsSET Space Environment Definitions

• Background Environment– Measured as a weekly averaged environment– Measurement is intended to represent the long-term changes in

the space environment.• Solar Storm Environment

– Solar storm is “S3” level or greater as defined by the NOAA Space Weather Scale.

– Measured as an hourly averaged environment during a solar storm

– Measurement is intended to represent the short-term changes in the space environment.


Success Criteria Success Criteria -- CREDANCECREDANCE

See “Frequency of measurement”See” Frequency of measurement”

Electron Exposure

1x106 ions at LET>3 MeVcm2/mg

> 40 MeV integral proton fluenceto 1x109 level

Operation to 5 krads (Si)

1 measurement of background environment in each 7-day period for 3 months

Minimum Success

1x107 ions at LET>3 MeVcm2/mgHeavy Ion Exposure

> 40 MeV integral proton fluence to 1x1010 level

Proton Exposure

Operation to 25 krads (Si)Total Dose

1 measurement of background environment in each 7-day period for 1 year,Hourly measurements of environment for 2 solar storms

Frequency of measurement

Full SuccessMeasurement

CEM Rationale: For minimum success, 3 months of operation provides sufficient environment to validate investigations. For full success, 1 year of operation provides sufficient environment to validate investigations.

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Success Criteria Success Criteria -- DIMEDIME

NANAElectron Exposure

1x106 ions at LET>3 MeVcm2/mg


Operation to 5 krads (Si)

1 measurement of background environment in each 7-day period 3 months

Minimum Success

1x107 ions at LET>3 MeVcm2/mgHeavy Ion Exposure


Proton Exposure

Operation to 25 krads (Si)Total Dose

1 measurement of background environment in each 7-day period for 1 year,Hourly measurements of environment for 2 solar storms



Rationale: In order to reduce engineer uncertainties, dosimetry systems must be exposed to an adequate level of the environment. Full success levels are the points where dosimetry measurements start to saturate.


Success Criteria Success Criteria -- ELDRSELDRS


NA


Accumulation to 5 krads (Si)

1 measurement in each 7-day period 3 months

Minimum Success

NAHeavy Ion Exposure


Proton Exposure

Accumulation to 25 krads (Si)Total Dose

1 measurement in each 7-day period for 1 year



ELDRS begins to occur during ground testing at ~5krad level. In order to see space correlation to Mil-1019.6 test method, this level needs to be reached. ELDRS begins saturating during ground testing at ~ 25krad level. In order to see space correlation to Mil-1019.6 test method, this level needs to be reached. Proton exposure maps to secondary science of proton damage factors.

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Success Criteria Success Criteria –– COTSCOTS--22

1x106 ions at LET>3 MeVcm2/mg1x107 ions at LET>3 MeVcm2/mgHeavy Ion Exposure



NA

> 25 single event effects or 3 months of operation

Minimum Success


Proton Exposure

NATotal Dose

>100 single event effects or 1 year of operation



Current ground test methods require a minimum of 1x106 ions/cm2 per test run. 25 SEUs provides adequate correlation to validate the test methods and prediction techniques; conversely 3 months is adequate to invalidate if fewer events recorded. For full success, current ground test methods recommend a minimum of 1x107 ions/cm2 per test run. 100 SEUs provides full correlation to validate the test methods and prediction techniques as well as mitigation and simulation methods; conversely 1year is adequate to invalidate if fewer events recorded.


BackupsBackups

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FlowFlow--down of SET Requirementsdown of SET Requirements• Statement 1: New framework supporting the Vision for Space

Exploration– Explore the Earth-Sun system to understand the Sun and its effects on

Earth, the solar system, and the space environmental conditions that will be experienced by human explorers

– Demonstrate technologies that can improve future operational systems• Statement 2: Precursor to the framework, the NASA Strategic Plan,

and its applicable science roadmap, the Sun-Earth Connection (SEC) Roadmap. – To understand and protect our home planet and – To explore the universe and search for life

• These 2 statements frame the interests of Office of Science, the LWS Program and, consequently, the SET project: – Understand solar variability and its effects on the space and Earth

environments with an ultimate goal of a reliable predictive capability of solar variability and response

– Obtain scientific knowledge relevant to mitigation or accommodation of undesirable effects of solar variability on humans and human technology on the ground and in space

– Understand how solar variability affects hardware performance and operations in space


SET Science Investigations Support of SET Science Investigations Support of LWS InterestsLWS Interests

• The SET project addresses these requirements by performing science investigations that either mine existing data or collect new data in space to yield products.

• As a stand-alone mission, the SET responds to SEC research focus area by addressing each LWS interest:– Understand solar variability and its effects on the space and Earth

environments with an ultimate goal of a reliable predictive capability of solar variability and response

• Perform in situ measurements of the space environment on SET missions to determine long-term and short-term extremes in space weather conditions

– Obtain scientific knowledge relevant to mitigation or accommodation of undesirable effects of solar variability on humans and human technology on the ground and in space

• Develop products from SET and non-SET missions that can be used to mitigate the destructive effects of space weather on mission design and operation

– Understand how solar variability affects hardware performance and operations in space

• Characterize the effects of space weather on technologies via technology flight investigations including measurement of the correlative space environment

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Proposal Solicitation/Peer Review ProcessProposal Solicitation/Peer Review Process

Mail-In Reviews

(MIR)

• > 2 reviews per proposal

• Peer review services consolidates reviews of each proposal

• Co-chairs review all proposals in their Panel

Peer Review Panels(PRP)

• 1 Panel per Peer Review Panel per Technology Area

• Review results of Mail-In Reviews

• Provide consensus on Adjective Rating and Major Strengths and Weaknesses for each proposal

• Prepare Panel Reports for presentation to SRC

SelectionRecommendation

Committee(SRC)

• Chaired by Science Missions Directorate Official

• Review results of each Peer Review Panel

• Make recommendation for selection of proposals for funding

Selection Announce

-ments

• Notify proposers of results of selection

• Technology solicitation– Open competition: US industry, academia, government labs– Issued by NASA/HQ

• Peer Review led by peer review services

SelectionBriefing to

ScienceMission

DirectorateOfficial

• Review selection recommendations

• Make selections

Peer Review

Panel and Selection

CommitteeFormation

• LWS/SET personnel are fire-walled.

• LWS consultants cannot be reviewers.

• Industry reviewers cannot review industry proposals.

• Reviewers do not review proposals from his or her institution.


SET Access to SpaceSET Access to Space

• SET consists of a series of SET Missions (SET-1, SET-2, etc.)• Payloads are selected by matching the exposure requirements of

flight investigations to characteristics of the space environment provided by each flight opportunity.

• Budget does not include spacecraft or launch.– Must work with US and International programs for access to space.

• Status of access to space– SET-1 Mission is a payload on AFRL’s DSX mission– Negotiations ongoing with other DoD agencies

• Defense Threat Reduction Agency• Unnamed DoD Agency

– SET Project Scientist is Co-I with Boeing’s proposed spacecraft in the Exploration InSTEP* Program Element – High Orbit Spacecraft Testbed(HOST)

• 1-year Phase I begins April 2005 and goes through Phase B/CDR• If selected after Phase I, will become SET-2 Mission

– On-going technical interchange meetings with ESA/ESTEC to develop proposals to ESA’s PROBA spacecraft program

*In-Space Technology Experiments Program (In-Step)

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NRA #1 NRA #1 –– Products from Data Investigations (1)Products from Data Investigations (1)

• Solar arrays– Physics based models and software tool to predict degradation on multi-

junction solar cells validated with on-orbit data/NRL• Spacecraft charging/discharging

– Theoretical determinations of internal electric fields during charging events/JPL

– Correlation of bulk charging and discharging with high-energy electron flux/energy spectra/JPL

– Surface charging indices and fitting functions for use with NASAguidelines/SAIC

• Imaging technologies– Model of Coulomb and nuclear interactions of ions with semiconductor

materials for calculating degradation due to non-ionizing energy loss for space environments/GSFC

– Drift-assisted charge diffusion model and software tool to predict transient noise in imaging arrays validated with on-orbit data/PRT


NRA #1 NRA #1 –– Products from Data Investigations (2)Products from Data Investigations (2)

• Building block technologies for advanced spacecraft and instruments– Single event upsets

• Particle nuclear interaction model of elastic interactions with semiconductor material providing improved predictive capability/Clemson University

– Enhanced low dose rate• Preliminary ionizing dose degradation models for bipolar semi-

conductor materials to reduce design margins and improved ground test qualification procedures/NAVSEA-CRANE

– Dose enhancement in electron environments• Improved guidelines for use of high density shielding materials

in electron dominated environments/Aerospace– Electrostatic Return of Contaminants (ESR) on surface

materials• Software tool to predict the electrostatic return of spacecraft

emitted molecules that are ionized and attracted back to the spacecraft by the spacecraft electric potential on its surfaces/Rantanen

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NRA #2 NRA #2 -- Space Investigations (1)Space Investigations (1)

• Cosmic Radiation Environment Dosimetry and Charging Experiment (CREDANCE)/QinetiQ– Correlative Environment Monitor (CEM)

• Energetic Particle Spectrometer for Characterizing the Environment Around the LWS-SET Spacecraft. Also referred to as a Light Particle Detector (LPD)/PSI– Correlative Environment Monitor (CEM)

• Dosimetry Intercomparison and Miniaturization/Clemson University– Compare low-cost, high-return space radiation environment monitoring

techniques• Space Flight Evaluation of the Radiation Performance of

PolyRAD/Longhill– Characterize effectiveness of high-density shielding

• Definition of the Mechanisms for On-Orbit Degradation of Variable Emissivity, Variable Absorptivity and Variable Reflectivity Materials Degradation/PSI– Demonstrate active materials experiment– Characterize synergistic effects of space environments in the absence of

Atomic Oxygen


NRA #2 NRA #2 -- Space Investigations (2)Space Investigations (2)

• Development of Space-Based Test Platform for the Characterization of Proton Effects and Enhanced Low Dose Rate Sensitivity (ELDRS) inBipolar Junction Transistors/Arizona State– Develop physics based model of ELDRS– Validate ground test protocols for ELDRS ground based testing

• Total Dose and SEU Radiation Hardness Degradation Due to the Addition of Built-In Self Test (BIST) to Mixed Signal Electronic Circuits/Ridgetop– Determine effect of BIST addition to mixed signal circuits on its total dose

and single event upset (SEU) radiation hardness– Verify Ridgetop’s design rule checker software for BIST for total dose and

SEU radiation effects in space environment on a realistic mixed signal circuit.

– Validate models and ground test protocols for SEU’s on an A-D Converter (ADC) in space radiation environment

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SET Pathfinder InvestigationsSET Pathfinder Investigations

• Existing peer-reviewed investigations from Space Technology Research Vehicle 1D (STRV-1D) were brought to our attention.– Spacecraft downlink failed after a few weeks of operation

• Evaluated investigations for application to LWS SET goals• Requested and received approval to support 4 space

investigations– COTS-1a: Linear Enhanced Low Dose Rate Sensitivity

(ELDRS)/NAVSEA-CRANE• Validate ELDRS ground test protocols

– COTS-1b: Linear Single Event Transients (LSET)/Aerospace• Develop physics based model of singe event transients

– COTS-2: Digital COTS/CNES• Validate approaches to mitigate single event effects by comparing

simulation techniques, performance models, and on-orbit data– COTS-3: Optocouplers/GSFC

• Validate degradation and upset rate models

living with a star space environment testbed · 2009-05-20 · exp 1 exp 2 exp n exp i/f spacecraft...

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