Parallel NSS Design Motion and Sensors

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Parallel NSS DesignMotion and Sensors

• Jeff Steinman Jim Kilgore
• Metron Incorporated
• July 30, 1998

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Topics

• Parallel NSS Project Background
• SPEEDES Status
• Demo Scenario Description
• Parallel NSS Software Design

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Historical Time-Line

NSS HLA-Integration Framework
Object Proxies
Interactive Support
JSIMS
GVT With Flow Control
Breathing Time Warp
Proximity Detection (Best Paper PADS)
Process Model Macros
BMDO JNTF
Parallel IMPORT
SPEEDES
PADS
Breathing Time Buckets
Air Defense
Lazy Cancellation with Tolerances Incremental St
ate Saving
JPL JNTF LANL NRL Demo
Event Horizon (PADS)
Wargame 2000 TISA
Metron Distribution
HPCMO-CHSSI Parallel NSS
SPEEDES Version 0.4
Time Warp
Metron
Aerospace
MITRE
Northrop
AEgis Research
LANL
NRaD
NRL
JNTF
Dartmouth
MCNC
SIS
OriginalSim
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Parallel NSS Development

• Phase 1 (May 1996 - December 1997)
• Develop infrastructure on top of SPEEDES needed
  to parallelize NSS
• Object Proxies (distributed objects technology)
• Library of motion types with coordinate system
  transformations
• Data Distribution Management (scalability)
• Configuration management of SPEEDES software
• Delivery mechanism (Multiplatform build system)
• Adopted by mainstream DoD simulation projects
• Wargame 2000, JSIMS, etc
• Formation of configuration management group to
  coordinate future enhancements
• Design targeted to support HLA (automatic
  integration and/or SPEEDES-based RTI)
• Phase 2 (January 1997 - December 1998)
• Porting/developing models for Parallel NSS (alpha
  testing)
• MPI version of the SPEEDES Communications Library
• Phase 3 (January 1998 - September 1999)
• Refining models for Parallel NSS (beta testing)

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Portability Issues

• Standardized communications library interface
• Encapsulates optimizations for different hardware
  architectures
• High-speed shared memory support uses standard
  UNIX system calls and is seamlessly integrated
  with network communications between machines
• Message Passing Interface (MPI) communications
  library supports massively parallel distributed
  memory machines
• Other protocols can be supported (ATM, Myranet,
  RMP, etc.)
• Automatic efficient data marshaling between
  heterogeneous machines
• Supported machines, operating systems,
  compilers
• Machines
• PC, Workstations, Origin 2000, Convex Exemplar,
  Paragon, Cray J90, Cray T3E, etc...
• Operating Systems
• Linux, Windows NT, IRIX, Solaris, HPUX, etc...
• C Compilers (note, can also integrate with ADA
  and FORTRAN)
• Apex, Native compilers, Centerline, gcc, Visual
  Age C, etc...

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Architecture Functional Components

Sequential NSS
HLA-Integration Framework
HLA Federate
Future Simulation
HLA Run-Time Infrastructure External Interfaces
NSS and Wargame 2000
Parallel IMPORT
Extended Interfaces HLA Management
Services (Controllers, Event Handlers,
Hierarchical Grids, Object Proxies,
Precomputations, Dynamic Attributes)
Sequential Time Management
Fixed Time Buckets
Breathing Time Buckets
Time Warp
Breathing Time Warp
SPEEDES Event-Processing Engine (Event List
Management, State-Saving, Rollbacks, Message
Handling)
SPEEDES Communications Library
Host User Communications Interface for External
Modules
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SPEEDES HLA

• SPEEDES Approach provides HLA-like services
  through middleware layer of services
• Supports automatic integration with any RTI
  transparently
• Functionality inside dotted line (see figure
  below) can evolve into a fully-functional RTI
  (e.g., HLA version 1.3 interface)
• Support for HLA on high-performance computers
• Full support for time management DDM
• Novel concept Federates outside of SPEEDES can
  interact with a SPEEDES-based simulation through
  HLA interfaces

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SPEEDES Constructs Used In Parallel NSS

• Object managers and simulation objects
• Represent state of simulated entities
  (distributed to processing nodes)
• Events
• Time-tagged computations that can change the
  state of a simulation object and/or schedule new
  events for the future
• Can be methods on simulation objects or event
  objects
• Object Proxies
• Represent objects on remote machines
• Represents public interface to entities on remote
  nodes
• Supports external systems through the Object
  Proxy State Manager
• Key to providing HLA and DIS integration
• Library of dynamic attributes (i.e., time-based
  equations) such as motion
• Components Event Handlers
• Encapsulates models and their controlling
  mechanisms
• Interrupt driven style

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SPEEDES Constructs Used In Parallel NSS

• Parallel IMPORT Process Model Constructs
• ScheduleProcess() interface for starting up a
  process
• A process is a re-entrant event
• WAIT - passes fixed amount of time
• WAIT_FOR ...- waits for a semaphore to be set
  (can time out)
• Logical Semaphore
• Integer Semaphore
• Float Semaphore
• Counter Semaphore
• TELL - asynchronously starts up a process (looks
  like a method call)
• ASK - allows objects to communicate through
  method calls
• Blocking style programming interface for
  returning arguments in method call
• Guaranteed no deadlocks (underlying mechanism is
  still discrete-event)

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Scenario

• Four Ships moving along great circle trajectories
  using scripted motion between way-points
• Described in Ship.par file
• Each ship has its own start time
• Velocity between way-points scripted
• Ship_0 Honolulu, Tokyo, Singapore, Honolulu
• Ship_1 Honolulu, Singapore, Tokyo, Honolulu
• Ship_2 Norfolk, AtlWayPt1, Havana, AtlWayPt2,
  Norfolk
• Ship_3 Norfolk, AtlWayPt2, Havana, AtlWayPt1,
  Norfolk
• Each ship has 2-3 radar sensors (50 km, 100 km,
  200 km ranges)
• 100 Randomly moving objects across the globe
• Described in RanMot.par file
• 500 km range sensor
• Altitudes can change
• Mach-1 velocity

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Inheritance for Simulated Entities

SimObj
S_HLA
S_ENTITY
S_MOVING_ENTITY
S_FIXED_ENTITY
S_Ship
S_RanMot
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S_HLA and Object Proxies

S_HLA
Publish
Add Subscriber
Object Proxy
Remote Object Proxy List
UnPublish
Remove Subscriber
Publication Class List
Subscribe
Deliver Proxy Pointer

Remote Object Handle Distribution List
UnSubscribe
Undeliver Proxy Pointer
Touch Proxy
Schedule Update
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Object Proxy Input File (Objects.par)

• // This is the object proxy file for Parallel NSS
• // base class for everybody
• ENTITY
• define logical Alive
• define list SensorList
• // All moving entities inherit from this
• MOVING_ENTITY
• reference INHERIT ENTITY
• define float Vmax
• define dynamic_position Position
• // All fixed entities inherit from this
• FIXED_ENTITY
• reference INHERIT ENTITY
• define position Position

• Ship
• reference INHERIT MOVING_ENTITY
• reference SUBSCRIBE ENTITY
• RanMot
• reference INHERIT MOVING_ENTITY
• reference SUBSCRIBE ENTITY
• // Sensor List Elements go in the Entity
• // SensorList
• SENSOR_LIST_ELEMENT
• define list DetectedObjects
• // Object Ids go in Sensor List Elements
• OBJECT_ID
• define int ObjectId

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Composition of Entities

S_ENTITY
Platform Component List
Motion Component List
Weapon Component List
Sensor Component List
Track Correlation Component List
Command Control Component List
Communications Component List
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Radar Component

Remote Proxy Counter Semaphore
COMPONENT
Remote Proxy Semaphore List
Detectable Proxy List
Sensor Component
Sensor Model
Radar Scan Process
Radar Component
Radar Precomputation Process
Radar Model

Radar Reflect Attributes
Radar Update Attributes
Radar Discover Object
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Radar Precomputation Process

• Precomputation determines when remote proxy
  enters and exits a radars field of view
• One precomputation process per remote discovered
  object proxy for each radar component
• Discover Object event handler initiates the
  process (can provide filtering)
• Adds/removes the remote proxy to the radars
  Detectable Proxy List in logical time
• Uses maximum velocity to provide first level
  filtering
• Coordinates the sensors detectable proxy counter
  semaphore which is used by the radar scan process
  to go to sleep when there are no remote proxies
  within range
• Avoids polling by the radar scan process
• Is interrupted when motion changes
• The entitys own motion
• The remote entitys motion

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Radar Scan Process

• Forms detections
• Uses constant scan time for radar
• Goes to sleep when there are no detectable
  entities
• Passes truth into the Radar Model and receives
  statistically smeared detections
• Will pass detections to track fusion components
  to determine perceived targets (will use a
  two-stage Kalman Filter to track position)

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Parallel NSS Radar Sensor Model

• Parameterized Radar Model
• Maximum Range Sigma Range
• Sigma Range Rate
• Sigma Angle
• Future enhancements
• Line of sight calculation
• Use of radar equation for returned signal power
• Generation of false detections
• Ground clutter returns
• Forms Detections
• Range with Gaussian error statistics
• Range Rate with Gaussian error statistics
• Directional Vector with symmetrical Gaussian
  angular error statistics

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Detections

• DETECTION base class
• Generic detection types
• Supports multiple types of sensors trackers
• Encapsulates truth data (Radar Scan Process)
• Target and sensor positions and velocities
• Target Id
• Time of detection
• Generic reusability through virtual functions
• RADAR DETECTION
• Encapsulates truth data (Radar Scan Process)
• Radar cross section
• Encapsulates perception data (RadarModel)
• Range, sRange
• Range rate, sRange rate
• Directional vector from sensor to target, sAngle

DETECTION
RADAR DETECTION
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Scripted Motion Component

COMPONENT
Motion Component
Dynamic Position Attribute
Scripted Motion Component
Constant Motion
Great Circle Motion
Change Scripted Motion
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Motion

• Dynamic position attribute (managed by Motion
  Component) is mapped into each entitys Object
  Proxy
• Motion described using time-bounded motion-type
  segments
• ConstPosition(-8,t0), GreatCircle(t0, t1),
  GreatCircle(t1,t2), , ConstPosition(tn, 8)
• SPEEDES provides library of motion types with
  coordinate system transformations
• Constant positions cap end points of motion
• Great circle equations of motion
• Constant velocity even when changing altitude
• Ships move between locations specified in
  Locations.par file
• Random Motion objects are used to test
  scalability for large numbers of objects
• Humans can change motion of any object during
  execution
• Dynamic position attribute is automatically
  delivered to remote objects when motion is changed

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Interactive Capabilities

• Pause/resume
• Can stop GVT from advancing
• Can set up initial pauses if needed
• Named queries
• Entities can be queried for information while the
  simulation is executing
• Change Scripted Motion Command
• Entities can be redirected to move to named
  locations
• Object Proxy State Manager
• Sends the changes made to object proxies inside
  SPEEDES to the outside world with logically
  correct time management

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Next Steps

• Integration of other NSS models
• Weapon systems, communications, command control
• Parallel NSS will support other SPEEDES
  applications
• Parallel NSS uses all of the SPEEDES constructs
  as they were designed to be used
• Parallel NSS software demonstrates interfaces
• Code walk-through for Wargame 2000 JSIMS
• Graphical map interface
• Will be based on the Object Proxy State Manager
• Can be done generically to support all DoD
  SPEEDES applications
• Would like to develop a complete analysis package
  for SPEEDES
• Currently not funded, but all SPEEDES users will
  want this tool
• Parallel NSS currently achieving good speedup