SIMSAT 3'0 a platform independent version of ESOCs simulation infrastructure

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SIMSAT 3.0 a platform independent version of
ESOCs simulation infrastructure
N. Lindman ESA/ESOC, Darmstadt,
Germany J.Eggleston, H.Boyer VEGA IT GmbH,
Darmstadt, Germany A.Pidgeon, D.van der Zee
SciSys (Space and Defence) Ltd, Chippenham,
UK N. Di Nisio Terma GmbH, Darmstadt,
Germany F.Burro Dataspazio S.p.A, Rome, Italy
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Presentation Overview

• Project Summary
• Project description, its participants working
  practices
• Architectural Overview
• Differences to SIMSAT 2.0
• Description of the main architectural differences
• Platform Independence
• How and why are we platform independent?
• Project Status
• How things are, how they look, and road-map
• Summary

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Project Summary Products

• Project requires moving SIMSAT 2.0, Generic
  Models 2.0 and Ground Models 2.0 to Linux, based
  on open standards
• SIMSAT 2.0
• Kernel Run-time engine for the simulation
• MMI Default method of controlling and
  interacting with the simulation
• Generic Models
• SIMPACK, SENSE, PEM and SimDyn
• Ground
• GMM, MCS DIF, TTC Streams, GVS

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Project Summary Work Breakdown

• VEGA is prime contractor with SciSys, DataSpazio
  and Terma subcontractors
• Work share principles...
• Each company takes responsibility for one of the
  main products
• Each company has work packages on each product
• Each company responsible for their own code up to
  provisional acceptance
• After provisional acceptance, company responsible
  for product must fix all problems with that
  product

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Project Summary Working Practices

• Component Monitoring to allow responsible
  companies to monitor components produced by other
  companies
• Hot desks in the VEGA offices for the use of
  sub-contractors to empower easier integration
• Off-site access to the source code to empower
  rapid problem fixing
• using CVS repository and a SSH link
• Web sites to empower better teamwork
• Project Portal with discussion groups and
  documents
• JIRA Issue tracking

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Architectural Overview
Models
Infrastructure
Generic Models
Mission Specific
Interface
Ground Models
MMI
SMP 1 / 2
Scheduler Viewer
Kernel
Logger Viewer
Scheduler
e.g. Mimic Diagram
Logger
e.g. Special ANDs
e.g. Circular Logger
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Pluggable Components

• SIMSAT 2.0 supports components in the Kernel only
• E.g. TTC Streams and concurrent scheduler
• But MMI is statically compiled
• Impossible for third parties to alter or
  improve the MMI
• SIMSAT 3.0 will use components for the Kernel and
  MMI
• Third party code needs to meet interface
  requirements
• CORBA interfaces for Kernel, Java interfaces for
  MMI
• Component can be loaded into Kernel or MMI at run
  time
• Component need not be delivered with SIMSAT

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Pluggable Components Benefits

• Easy for third parties to add items - Just
  follow the interface rules (and semantics)
• Kernel and MMI can be augmented with new
  components to replace or enhance the
  functionality of the existing ones, e.g.
• A new logger that uses databases?
• A component to record and replay data values?
• Mimic diagrams of the simulated systems?
• Simulator specific control panels?
• System is more expandable
• System is more maintainable
• New features do not have to complicate existing
  components that are tried and trusted

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Kernel Services

• Kernel Services have been refined
• Kernel Services now on the same footing as models
• Allows kernel to be much more dynamic
• No compulsory components
• Kernel Services can be scripted
• Allows users to configure the kernel at run time

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Kernel Services - Benefits

• Kernel is no longer a closed box
• Need three loggers?
• Dont need a scheduler?
• Simulation developers can use debug versions of
  components to help solve problems
• Schedulers that automatically performance profile
  the simulation
• Different types of components for different tasks

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Java MMI

• SIMSAT 3.0 MMI has been redesigned from scratch
• SIMSAT 2.0 MMI is implemented using MFC C
  classes
• Java Swing now used as the API
• MMI now scriptable
• MMI now utilises components
• Allows easy plug in of third party graphical
  objects
• Currently using Suns JVM, version 1.4.2

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Java MMI - Benefits

• Java is much easier to write and maintain than
  C
• Automatically supports multiple platforms
• Better developer knowledge for Java GUIs than MFC
• Extensive Java libraries as part of the standard
  language
• XML
• CORBA

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CORBA

• SIMSAT 2.0 uses COM as the middleware
• CORBA has replaced COM for SIMSAT 3.0
• COM IDL definitions of the Kernel interfaces were
  ported to CORBA IDL
• Conversion
• Refactoring
• Much lower coupling and higher cohesion of
  interfaces
• But many more interfaces
• Need to replace some operating system features
• We use omniORB 4.0.3 at present

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CORBA - Benefits

• CORBA is an open standard
• Many open source implementations
• Many different platforms
• CORBA is used for the Mission Control System
  middleware as well

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Rhino

• SIMSAT 2.0 used the Microsoft script engines
• Provides access to the simulation objects from
  JScript
• Provides debugging facility
• Rhino is an open source script engine written in
  Java, with CORBA connectivity packages
• LiveConnect used for communication with Java
  objects
• JSCorba used for connecting JavaScript to CORBA
  objects
• Rhino Debugger for debugging scripts

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Rhino - Benefits

• We still control the models through JavaScript
  (JSCorba)
• We can still debug the scripts (Rhino Debugger)
• We can also control the MMI
• Automated system tests for Kernel and MMI

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Platform Independence

• Middleware is CORBA
• Available in compatible stable formats on
  virtually every platform
• Operating System independence
• Use of library to isolate platform dependencies
• Use of third party software to achieve easy
  portability of this library, e.g. ACE, APR or
  omniThreads
• MMI is Java based
• Available on all modern platforms
• Use of XML where possible

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Project Status

• Basic versions of critical system components are
  complete
• First integration of Kernel and MMI systems now
  underway
• Will result in proof of concepts
• Second phase of project is planned to be filling
  the gaps
• Current Delivery Dates
• Internal Engineering Drop Delivery due early next
  month
• SIMSAT 3.0 due early November 2004
• Generic Models 3.0 and Ground 3.0 due early 2005

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A Systems Engineering Company
VEGA Informations-Technologien GmbH Hilpertstraße
20 A 64295 Darmstadt, Germany Tel., Fax 49
(0)6151 / 82 57-0, -99 WWW www.vega.de