Behavior Design Patterns: Engineering Human Behavior Models

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Behavior Design PatternsEngineering Human
Behavior Models

• Glenn Taylor and Robert Wray
• Soar Technology, Inc
• at Behavior Representation in Modeling and
  Simulation 2004

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Contents

• Introduction
• TacAir-Soar
• Fully autonomous system for modeling and
  simulating the tactical air domain
• Behavior Patterns in TacAir-Soar
• Examples
• Move-to-target Pattern
• Ground Attack Pattern
• Conclusion

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Introduction

• Since 1991, DoD has been working on
  standardization of modeling and simulation
  software
• Reduce the development and maintain costs by
  integrating simulators (for training, planning
  operations, studying past operations) in
  army/navy/air force
• HLA (High Level Architecture) became an IEEE
  standard in 2000
• Providing time synchronization, communication
  mechanism between simulators running in parallel

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• ModSAF
• Modular Semi-Automated Force
• Software modules and applications that construct
  Distributed Interactive Simulation and Computer
  Generated Forces entities for realistic training,
  test, and evaluation on the virtual battlefield.

• Every vehicles and weapons in U.S. and NATO, and
  past operations are modeled in ModSAF
• U.S. and NATO use ModSAF for their simulation
• Generated forces in ModSAF is not so smart
• Human operators play friend and foe

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Motivation

• Military simulators needs to imitate
  human-behaviors (combat operations) to make
  virtual battle field more realistic
• Simulate imaginary enemy, evaluate strategies,
• Developing human behavior models often results of
  high costs and long development time
• Due to the lack of reusing methods/techniques
• Behavior models and applications are often
  constructed in an ad-hoc manner (from scratch),
  and not easy to reuse
• Differences in implementation technologies (e.g.,
  programming languages and simulation environment)
  also make difficult to reuse models

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Research Objective

• Reuse common patterns of human behavior by
  leveraging the notion of design patterns
• Behavior Design Patterns
• Behavior Design Patterns describe successful
  designs for agent behaviors that appear
  repeatedly in agent system designs
• Agents military aircraft pilots
• This research focus on military domains

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Behavior patterns in TacAir-Soar

• The authors started with studying behaviors in
  TacAir-Soar
• As an initial source for understanding and
  constructing general behavior patterns
• TacAir-Soar defines a behavior model of military
  aircraft pilots that can execute most of the
  operations performed by fixed wing aircrafts

Fixed-wing
Rotary-wing
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Soar and TacAir-Soar

• Soar
• the basic cycle of taking a State applying an
  Operator, And generating Result
• http//sitemaker.umich.edu/soar/home
• A framework for developing systems that exhibit
  intelligent behavior
• A systems consists of agents
• Agents run in parallel according to their own
  rules
• Soar/IFOR (Intelligent FORce)
• Archive autonomous intelligent forces in
  simulators by combine ModSAF and Soar

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TacAir-Soar

• TacAir-Soar
• One of applications in Soar/IFOR
• System for modeling and simulating the tactical
  air domain (i.e., military aircrafts and combat
  airspace)
• Military aircrafts and battle fields/combat
  airspaces are modeled using ModSAF
• Enemy forces are controlled by Soar
• Behavior patterns of all military aircrafts and
  pilots in U.S. and NATO are modeled
• consist of 5000 rules
• Providing an interfaces (e.g., virtual cockpit)
  that allow pilots (trainees) to fly and engage
  operations in real-time
• Intelligent Agents for Interactive Simulation
  Environments, AI Magazine, 1999

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• The authors investigate TacAir-Soar
• What should be called a behavior?
• The authors focus on tactical level
  decision-making process
• Decision making process in agents (pilots) is
  organized in the form of hierarchical tasks,
• ? Engaging an enemy requires being within range
  of a weapon,
• ? Requires maneuvering into position with respect
  to the enemy,
• ? Requires knowing where the enemy is,
• ? etc, etc,

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Eight groups in behaviors

• Communications
• How and when to talk to other agents
• e.g., radio communication
• Missions
• Mission-specific behaviors, such as for
  air-to-ground missions or air-to-air missions
• e.g., air-to-air missile attack
• Control
• How to direct other agents to take action
• e.g., attack/return command
• Coordination
• How to work with other friendly agents
• e.g., ask air support during ground attack

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• Flying
• How to fly a plane
• e.g., Controlling pitch, roll, direction, speed,
  
• Navigation
• How to decide where to go and how to get there
• e.g., following a route, direct to the target,
• Situational Awareness
• How to manage the information in the environment
• e.g., wait for commands, surveillance,
• Action
• interactions with the simulation platform
• e.g., ??

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Navigation
Sub Categories
Categories
is-a relationship
Behaviors taken by agents
Launch Acceptance Region

• Behavior taxonomy
• Not design patterns yet

dependencies
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Behavior Design Patterns

• Behavior design patterns are derived from
  taxonomic analysis
• (how??)
• Same as the traditional software design patterns,
  each behavior design pattern consists of
• Pattern Name
• Problem the problem the pattern solves
• Solution description of elements that make up
  the design
• Consequences the results of applying the pattern
  and any tradeoffs in its use
• Example
• Variation points of variation in the pattern

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examples
solution
Air plane, tank,
Air / Ground domain

• Move-to-Target pattern captures regularities in
  movement behaviors

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High-level design pattern

• Patterns can describe designs at all levels of
  software designs
• In TacAir-Soar, a high-level behavior corresponds
  to the execution of an entire mission
• ? Entire mission can be one of behavior design
  patterns
• There are many common characteristics between
  different types of missions
• ? Pattern can abstract the difference and provide
  high-level view of missions

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Ground Attack Mission

• Strike and Close Air Support (CAS) missions share
  a great number of characteristics including
  similar data requirements and phase structures
• CAS use of military aircraft in a ground-attack
  role against targets in close proximity to
  friendly ground troops

• These two missions can be generalized as Ground
  Attach mission

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Some options after the mission

• Sequence of Ground Attack Mission
• Takes off and flies to some control point
• Awaits target information from the controller
• Executes its attack, joins together with
  accompanying aircrafts, and goes to some exit
  point (egress)

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Suppression of Enemy Air Defenses (to get the air
supremacy)
Other patterns used in this pattern

• State-based pattern notation

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• Ground Attach Behavior Design Pattern captures
  the general pattern of ground attack
• Domain experts can focus on the differences
  between the specific behaviors/patterns
• This is in contrast to current methodologies,
  where an engineer have to
• Implement the behavior from scratch, or
• Identify reusable pieces from existing
  implementations of close-air support, strike, and
  other related behaviors

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Conclusion

• The authors proposes behavior design patterns in
  the tactical air domain
• Patterns capture human behavior models appears
  repeatedly
• TacAir-Soar focus on fixed-wing air human
  behavior models, but the authors plan to expand
  the domain of patterns