Nazareth Bedrossian

1
Network Centric Computing (NCC)

• Nazareth Bedrossian
• Group Leader, Aerospace Systems
• The Charles Stark Draper Laboratory
• 2200 Space Park Dr, Suite 210
• Houston, TX 77058
• 281-333-2127
• naz_at_jsc.draper.com
• www.draper.com

2
Overview

• Introduction
• Network Centric Computing (NCC)
• Internet Computing
• Distributed Simulation
• Grid Computing
• Draper NCC Examples
• Demos

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What Is NCC?

• Networked computers for resource sharing and
  coordinated problem solving
• Context
• Business-To-Business (B2B), Peer-To-Peer (P2P),
  Application System Provider (ASP), Storage System
  Provider (SSP), Grid Computing, Internet
  Computing, Distributed Computing, etc
• Commercial Initiatives
• Sun, IBM-On Demand Computing, HP-Adaptive
  Computing

4
NCC Categories

• Internet Computing ? Distributed Users
• Centralized applications accessed by
  geographically distributed users
• Distributed Simulation ? Distributed Software
• Geographically distributed software subsystems
  which are assembled into complete simulations by
  geographically distributed users
• Grid Computing ? Distributed CPU Cycles
• Distribute computational load over geographically
  distributed resources

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Draper NCC Examples

• Internet Computing
• eSim Provides remote users web access to
  simulations
• VSSim Provides remote users capability to share
  models create simulations
• Distributed Simulation
• XNsim Provides remote users capability to share
  models create simulations

6
What Is eSim?

• Web Server Software
• Enables multiple users to access any simulation
  via the Web
• Current version runs under Unix OS
• An interactive version, eSimI, has also been
  developed

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An eSim Example

• Background
• Draper designs and flight certifies Shuttle
  On-orbit GNC system
• Use a high-fidelity 6DOF rigid plus flex-body
  simulation IOS (Interactive On-orbit Simulation)
• Provide support to MOD for Shuttle GNC system
  performance
• Desire an efficient method to support MOD
• Without eSim, MOD would call Draper personnel who
  would run IOS and call back with the performance
  data
• With eSim, MOD user can easily and directly run
  IOS and get performance data

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eSim IOS
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eSim Process
eSim Web Server
Simulation Web-Page
Simulation Owner Supplied
Inputs Web Page
Outputs Web Page
Owner Specified Input Variables
Web-Accessible Simulation Input Output Variables
Owner Specified Operational Modes
Simulation Driver File Execution Scripts
Owner Specified Output Variables
Simulation Interface Scripts
Simulation Postprocess Scripts
Postprocessing Tools
Simulation
Execute Simulation
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Comparing Web Server To Remote Login

• No need for expert users or training users to run
  simulation
• No need to use auxiliary software, such as
  visualization tools
• Limits the of configurations/parameters user
  has to deal with
• No need to jump-through-hoops in order to login
• No need for account access, hence no potential
  for loitering

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Comparing Web Server To Applets

• No need to rewrite simulation into applet
• Execution speed faster with natively compiled
  code
• Simulation results can be shared with multiple
  users
• Cant do this with an applet

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eSim Benefits

• Do more with less and do it faster
• Eliminate duplicate development/verification/CM
• Automate simulation processes, and result
  documentation
• Reduce risk
• Prevent errors caused by maintaining multiple
  versions
• Protect intellectual property rights
• Access to results without revealing source code
• Increase user base
• Access larger user base with no re-write or
  re-host overhead
• Simulations can be accessed from anywhere on any
  platform

13
eSim Examples

• Draper Station Analysis Tool (DSAT)
• Draper Station Simulation (DSS) for Mathworks Inc
• Hydraulic Actuator for Parker Hannifin Corp
• eSimI Demonstrator
• Shuttle Interactive On-orbit Simulation (IOS)
• More examples available at NCC website
• www.jsc.draper.com/ncc

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DSAT - Draper Station Analysis Tool
Station integrated GNC systems flight readiness
certification tool implemented in Matlab/Simulink
Web Interface
Desktop Interface
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DSS - Draper Station Simulation
ISS 3DOF RigidFlex simulation developed in
Simulink Used as a demonstrator for Web server
based computing possibilities
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Hydraulic Actuator
Hydraulic actuator simulation developed in
Simulink Provide access to aircraft hardware math
models for JSF program
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eSimI Demonstrator
Can change simulation parameters on the fly
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IOS - Interactive On-orbit Simulation
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Draper NCC Examples

• Internet Computing
• eSim Provides remote users web access to
  simulations
• VSSim Provides remote users capability to share
  models create simulations
• Distributed Simulation
• XNsim Provides remote users capability to share
  models create simulations

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What Is VSSim?
A Virtual System Simulation framework which
provides geographically dispersed user community
the capability to share models without revealing
source code and create simulations from them on a
central computer Used for Navy Trident Ballistic
Missile program
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VSSim Software Description

• Intuitive COTS-based graphical user interface
• Subsystem model repository that can be
  populated with models from a variety of
  languages/tools
• Process and configuration control, intellectual
  property protection
• Supports collaborative development processes
• Provides model migration pathways to
  hardware-in-the-loop simulation environments
• Supports long-term simulation requirements via
  XML layer

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VSSim Process

• MATLAB /SIMULINK/STATEFLOW
• C, C
• FORTRAN
• EASY5

Model Repository
GUI
Subsystem models dragged from repository to
modeling workspace

• Virtual system models solved using central
  integrators!

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VSSim Architecture
I C D
SIMULINK Model Source
SIMULINK
Auto- Generated Wrapper code
GUI And Simulation Engine
I C D
C, C Model Source
Editor
Auto- Generated Wrapper code
Framework External Modeling Interface

EASY5 Real- Time Inter- face
Etc.
Other
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Next Generation VSSim
SIMULINK Model Source
SIMULINK
EASY5
XML Model Definition
XML-to-EASY5 Model Interface Translator
XML Generator
GUI Sim Engine
I C D
Model Interface
Non-Real-Time Simulation User
Real-Time Interface
XML Model Definition
XML-to-Real Time Model Interface Translator
XML Generator
I C D
Real-Time Simulation User
Other?
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Draper NCC Examples

• Internet Computing
• eSim Provides remote users web access to
  simulations
• VSSim Provides remote users capability to share
  models create simulations
• Distributed Simulation
• XNsim Provides remote users capability to share
  models create simulations

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What Is XNsim?

• XNsim - eXtensible Network simulation
• Distributed simulation software
• Assemble simulations from remotely shared models
• written in different languages
• for different computing platforms
• for arbitrary connections between models
• for single/multiple community networks
• without revealing model source code

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Comparing XNsim with Centralized Simulation

• Dynamically scalable architecture without
  additional cost
• Can easily add new component model
• Substantially reduce development cycle time,
  risk, cost
• Dont need to develop complete centralized sim in
  order to find out that a subsystem does not work
• Inexpensive and very easy to use GUI based sim
  design
• Provides for remote execution control, i.e.
  start/restart

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XNsim Benefits

• Do more with less
• Eliminate duplicate development/verification/CM
• Test-Drive a model before buying it
• Protect investment in existing software base
• Integrate present with future
• Reduce risk
• Prevent errors caused by maintaining multiple
  versions
• Protect intellectual property rights
• Profit center
• Lease software via fractional or metered access
• Access larger user base with no re-write or
  re-host overhead

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XNsim Architecture
User
Simulation Initialization Outputs
Hub Network Server
Simulation Exchange
Component Server
Component Server
Component Server
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XNsim Components

• Designer
• Create and run sims from shared models
• Share
• Share models on subscriber network
• Master Server
• Maintains model library and maps simulation
  topology

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Designer
Sim Results
GUI
Creating a simulation
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Updating Designer
Designer After
Designer Before
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Designer - Model Parameters
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Share
GUI
Inputs
Outputs
Parameters
Component Editor
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Share Object Compiler

• To share a new function called sine.c
• Enter its name in the Share Object Compiler
  which compiles and links the XN native wrapper
  for this function

sine.c
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Master Server
Peer-to-Peer Supernode Maps Designer simulation
topology to shared components Connects community
of users to each other
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Global XN Demo - 2002 AIAA GNC Conference

• A simulation was assembled in Monterey, CA from
  subsystem models executing on nodes in Houston
  Munich
• University of the Federal Armed Forces, Munich,
  Germany
• Draper Laboratory, Houston, USA

Network Connection NetZero Dial Up
50kbps Roundtrip Latency 250msec
Munich Node Share Friction, Spring
Monterey Node Master, Designer
Houston Node Share Integrator, Sine