Transcript SPENVIS

ESA'S SPACE ENVIRONMENT INFORMATION
SYSTEM (SPENVIS): A WEB-BASED TOOL FOR
ASSESSING ENVIRONMENTAL EFFECTS IN
SPACECRAFT SYSTEMS
D. Heynderickx, B. Quaghebeur, J. Wera
BIRA, Ringlaan 3, B-1180 Brussel, Belgium
Overview
• Overview of space environment and effects
• Description of SPENVIS
• Architecture
• Models and tools
• Ongoing and future extensions and upgrades
• Commercial break
• Demonstration
What is SPENVIS?
• WWW based interface to models of the space environment and
its effects on spacecraft and components:
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radiation environment
dose, NIEL, SEUs, solar cell degradation
spacecraft charging
magnetic fields
atmosphere and ionosphere
meteoroids and debris
solar irradiance, …
Models are run over spacecraft trajectories or coordinate grids
Access to satellite data sets and geomagnetic indices
On-line help and extensive background information
Results in textual, tabular and graphical form
User Community
• Intended usage:
• spacecraft engineering
• scientific
• educational support
• Currently about 2,000
internationally registered
users
• Listed on NASA’s Technical
Standard site
• Used by major spacecraft
industries and universities
SPENVIS Architecture
• HTML interface which stores input parameters in text files
• CGI script spawns runs of stand-alone binaries
• Output from applications has been converted to
straightforward ASCII files with standard headers
• Output files can easily be downloaded and ingested in other
applications (e.g. Excell provides direct import of tables in
HTML files)
• Graphics are produced with IDL; this can be replaced by other
packages if needed.
• Ongoing development to move from CGI scripts to php, similar
to LAMP/WAMP (Linux/Windows-Apache-MySql-php).
• Very flexible architecture, easy to maintain and expand.
• Framework for other applications
Radiation environment
• Spacecraft orbit generator
• Runge-Kutta trajectory tracing
• Parameter input: 6 orbit
parameters, pre-defined orbit types
(heliosynchronous, GEO), Two Line
Elements
• Trajectory file uploads
• Environment models
• trapped protons (including
anisotropy) and electrons
• solar ions
• cosmic ray ions (GCR, ACR)
• Geomagnetic shielding for SEPs and
CRs
Radiation effects
• Radiation effect models
• ionizing dose
• non-ionizing dose
• solar cell degradation:
damage equivalent electron
fluence for different cell
type
• single event upsets
• Mulassis: Geant4 Monte
Carlo code for shielding
analysis
Radiation effects
• Sector analysis tool
• Basic building blocks (sphere,
box, cylinder) to construct 3D
model of satellite system
• VRML view of geometry
• 1D and 3D shielding
distributions can be folded with
flux and dose models
Magnetic Field
• Orbital and grid version
• Field models:
• internal: IGRF/DGRF
• external: Mead-Fairfield, Olson-Pfitzer
quiet and dynamic, Tsyganenko
87/89/96/01/04, Ostapenko-Maltsev,
Alexeev (ISO draft standard)
• Drift shell tracing
• Used for trapped particle models (automatic
selection of appropriate models) and
geomagnetic cut-off calculations
• Fortran library:
http://www.oma.be/NEEDLE/unilib.php/
Atmosphere and Ionosphere
• Models: NRLMSISE-00, MET V2, DTM, IRI-90, HWM
• Evaluation over spacecraft orbit:
• density, flux, and fluence of atmospheric or ionospheric
constituents on an oriented surface along an orbit
• erosion depths for atomic oxygen
• Over coordinate grids
Spacecraft Charging
• Data sets: GORIZONT/ADIPE, CRRES/LEPA
• LEOPOLD: Environment parameters as a function of altitude
• DICTAT: internal deep dielectric charging
• FLUMIC trapped electron model
• Cylindrical and planar configurations
• Estimate of electrical breakdown and suggestions for design
improvement
• SOLARC: interaction of solar array and spacecraft with plasma
environment
• EQUIPOT: analysis of spacecraft surface charging
• Simple isolated patch on conducting sphere model
• Includes major current systems
• Extended with Katz secondary electron model
Meteoroids and Debris
• Flux as a function of mass or diameter
• Grün meteoroid model
• Debris models:
• NASA-90
• NASA-96
• Impact risk analysis
• Critical impacting particle diameter derived from particle/wall
interaction model
• Probability of puncture
• Velocity distributions
Other Models and Tools
• Interface to data bases:
• satellite data: GOES-5-6-7-8-9-10/SEM, ISEE-1/WIM,
ISEE-2/KED, Meteosat-3/SEM-2, STRV-1B/REM,
CRRES/MEA, SAMPEX/PET, UARS/PEM, AZUR/EI-88,
MIR/REM
• magnetic and solar indices and parameters
• format: CDF (ISTP/IACG guidelines) with IDL interface and
plotting library
• Links to and from ECSS-E-10-04 standard
• Visualization of coordinate transformations
• Solar irradiance
• Geomagnetic cut-off maps
Ongoing and future extensions to SPENVIS
• Upgrade of the orbit generator: new trajectory types
(hyperbolic, parabolic, interplanetary, manoeuvres)
• Implementation of new environment models (SEP, CR, …)
• Implementation of new methods for solar cell degradation
studies: direct NIEL, SAVANT
• Upgrade of NIEL calculations (electron and neutron NIEL,
extensions to Mulassis)
• Extension of SEU module to new devices
• Upgrade of the sector analysis tool: more shapes, stand-alone
geometry interface, interface to Geant4 geometry definition
• Interface to Geant4 GRAS code: advanced toolkit for shielding
simulations
• Interface with external codes and tools (SIREST)
New interface in PHP
• The SPENVIS 5.0 interface will be completely written in PHP.
• Object oriented
• Well documented
• Easy to maintain or modify
• Easy to extend
• Easy to use without knowing all the implementation details
For the users
• Updated layout
• Better navigation possibilities including an expandable
navigation menu on the left
• Easier to work with
For the developers
• More flexible environment
• Object-oriented script with PHP classes that allow running
models and making plots
• Layout template that includes the expandable navigation
menu on the left
Currently implemented interfaces
• Spacecraft trajectories (SAPRE)
• Coordinate grid generator (GRID)
• Trapped Radiation Models
• Proton Models
• AP-8 (developed by NSSDC)
• CRRESPRO (developed by Air Force Research Lab)
• SAMPEX/PET PSB97 (developed by BIRA)
• Electron Models
• AE-8 (developed by NSSDC)
• CRRESELE (developed by Air Force Research Lab)
• AE-8 MIN Update ESA-SEE1 (developed by A.L. Vampola)
Commercial break
• SPENVIS is available at http://www.spenvis.oma.be/
• Use of the Web service is free, but needs registration
• Concept of ‘advanced’ users has been introduced: additional
control on input parameters and model runs for selected users;
this is one option for future commercialisation
• Commercial licences for PC Windows and Linux can be purchased
• One more GSTP contract extension has been approved, but
this will be the final one; afterwards, SPENVIS will have to be
self-supporting.
• SPENVIS is linked with ECSS E-10-04 standard on space
environment, and will be linked with new standards on
radiation effects and spacecraft charging