# Presentation: 660455

## STEP for Space Applications -TAS and NRF Development

- Hans Peter de Koning (ESA/ESTEC D/TOS-MCV)hdekonin@estec.esa.int
- Eric Lebègue (SIMULOG)Eric.Lebegue@esprico.fr

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Topics of this presentation

- Overview of Application Protocols
- Current status of implementations
- Brief demo with ESARAD
- STEP-TAS Converter Development Toolkit

- STEP-NRF
- Network-model
- Results Format
- Application Protocol

- STEP-TAS
- Thermal Analysis
- for Space
- Application Protocol

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## NRF and TAS main documents

- STEP-NRF
- Network-model
- Results Format
- Application Protocol

- STEP-TAS
- Thermal Analysis
- for Space
- Application Protocol

-  Definition and Results
- of Analyses, Tests
- & Operations
- Integrated
- Application Resource

- Space
- Domain
- Integrated
- Application Resource

- Thermal
- Analysis
- Integrated
- Application Resource

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Application Reference Model& Units of Functionality

**TAS**
- space_mission_aspects
- geometric_model
- kinematic_model
- thermal_radiative_model
- visual_presentation
- material_properties
- additional_physical_quantities_and_measures

**NRF**
- product_structure
- network_model_representation
- bulk_results
- parameterized_functions
- date_and_time
- general_support

- The ARM is organised in UoFs
- UoFs are collections of application objects and their relationships
- specified in the terminology of the application domain

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Main characteristics of NRF (1)

- Generic discipline-independent protocol
- Scope is definition and representation of:
- engineering objects represented by a network-model of discrete nodes and relationships between the nodes -network-model may contain a submodel hierarchy
- representation of properties of engineering objects for which result values can be predicted / observed at discrete states
- analysis, test or operational campaigns / cases / phases
- analysis, test or operational runs with associated results
- product structure compliant with AP203 CC1 / PDM schema
- relationships between product structure and network-model

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Main characteristics of NRF (2)

- Results are properties with value and unit
- Descriptive values (text string, item from enumerated list)
- Numerical values (scalar, vector, tensor)
- Parameterised function values (tabular interpolation, polynomial, limited expressions)
- NRF protocol has two separate parts:
- “_Static protocol_”, discipline-independent data structures
- _Dictionairies_ defining node and node-relationship classes, properties, property-qualifiers, property-value-range, ...
- Purpose of dictionairies is to enable flexible / adaptable use without need to re-issue the standard

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Main characteristics of NRF (3)

- Great care is taken to define light, efficient data structures
- Sparsely populated results value space
- Properties only one kind of unit in a data set
- Starting on development of a “best of both worlds” solution
- NRF for semantics
- HDF5 for efficient binary portable implementation method (HDF = Hierarchical Data Format by NCSA)

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Main characteristics of TAS (1)

- Self contained, complete Application Protocol
- AAM, ARM, Mapping Table, AIM, Express-G (586 pages)
- Conforms to TC184/SC4 methods and guidelines
- Geometry defined as AP203 CC4 surfaces
- Thermal-radiative model faces added as associated features
- Including possibility to support hierarchical submodel tree
- Associated notional thickness, surface material and bulk material
- Thermo-optical, thermo-physical properties for named material
- Concept of material property environment (Part 45)
- Kinematic model conform STEP Part 105 for articulating rigid bodies (e.g. rotating solar arrays, gimballed antennas)

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Main characteristics of TAS (2)

- Space mission aspects
- orbit arc (Keplerian and discrete ephemeris)
- space co-ordinate system, celestial bodies
- orientation, general and named pointing, spinning, linear rotation rates
- space thermal environment, including constant or lat/long dependent albedo / planetshine tables
- Boolean construction surfaces available for advanced tools
- STEP-TAS CC1 Abstract Test Suite
- conform STEP Part 3xx series
- test suite has been used in validation of TAS processors

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## TAS geometry and thermal-radiative models

- Shapes
- Primitives: triangle, rectangle, quadrilateral, disc, cylinder, cone, sphere, paraboloid
- Compound shapes
- Shapes conform to AP203 CC4 non-manifold surfaces
- Thermal-radiative model
- associates thermal-radiative faces with surface shapes
- thermal mesh
- surface and bulk material

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Illustration of basic TAS Keplerian orbit definition

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## STEP-TAS Conformance Classes

- thermal-radiative model
- with basic geometry

- kinematic
- model

- constructive
- geometry

- space mission
- aspects

- CC-1

- CC-2

- CC-3

- CC-4

- CC-5

- CC-6

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- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## STEP-NRF implementation status

- Read/write library available with C and FORTRAN binding
- Prototypes produced with CNES and Electricité de France
- Being prepared for use in ESA’s next generation integrated thermal analysis tool code-named ‘Polytan’ as an open post-processing interface

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## STEP-TAS Implementation Status

- Read/write libraries available with C and FORTRAN bindings
- Including programming tutorials / manuals (HTML and PDF)
- Ported and verified on 5 platforms: PC/Windows, Sun/Solaris, HP/HP-UX, Compaq-Dec/Tru64, SGI/Irix
- High level interface layer included at ARM/user domain level; Provides very significant savings in processor development effort
- Working processors
- CC1 processor in ESARAD 4.1.x (released summer 1999)
- CC1 processor in THERMICA release April 2000
- Currently large model cross validation ESARAD - THERMICA
- Proof-of-concept prototypes developed with NASA-JPL for TRASYS and TSS (1998)

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## ROSETTA in ESARAD

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## ROSETTA in Baghera View 

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## ROSETTA in THERMICA

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Doris in THERMICA

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Doris in Baghera View

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## DORIS in ESARAD

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Mars Rover in TSS

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Mars Rover in Baghera View

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Mars Rover in ESARAD

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## Mars Rover in THERMICA 

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000

## STEP-TAS future

- STEP-TAS Processor Development Kit available to thermal analysis tool vendors
- From SIMULOG at nominal cost EURO/USD 1000 (Jan-2000) Including initial e-mail tech-support
- Baghera View is available in addition (Contact Eric Lebègue)
- ESA is considering proposing STEP-TAS to ISO TC184/SC4
- New Work Item leading to new ISO 10303 part
- Continue large model cross-validation and performance tuning
- Initiate support for other conformance classes

- NASA's STEP for Aerospace Workshop at JPL

- 25-27 January 2000