Avatar Manipulation as a Metaphor for Virtual Reality System Simulator Interaction

1
Avatar Manipulation as a Metaphor for Virtual
Reality System Simulator Interaction

• Patrick Hartling
• Josh Brown
• Ben Scott
• Allen Bierbaum
• Carolina Cruz-Neira

2
Outline

• Virtual reality system simulator concepts
• VR Juggler simulator environment
• VR Juggler simulator plug-in architecture
• PySim
• Future work

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Virtual Reality System Simulators

• Previous experience?
• VR simulators exist to simulate the immersive
  system (CAVE, HMD, etc.)
• Allow development of applications without
  requiring constant access to the immersive system
• Utilize more readily available graphics
  workstations
• Input typically comes from a keyboard and mouse
  rather than 6DOF spatial devices
• Applications should be able to migrate easily
  from the simulator to the immersive system

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VR Juggler Simulator Environment

• Originally designed to be highly flexible
• Any device type (analog, digital, glove, etc.)
  can be simulated
• Any combination of device types can be mixed
• Separate head and camera
• User can manipulate the view into the scene
• Head shows user body position

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VR Juggler Simulator Environment
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VR Juggler Simulator Environment

• Difficult to use
• Simulated position devices each have twelve key
  presses and/or mouse movements
• Combining head, wand, and camera controls results
  in up to 36 total commands to remember
• Syntactic inputtends to be harder to learn and
  remember
• Semantic input is preferred by UI designers

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VR Juggler Simulator Plug-ins

• Anyone can write a custom simulator for VR
  Juggler
• Loaded dynamically at run-time based on display
  configuration
• This allows combining of multiple simulators
• Simulators act as both input devices and output
  devices
• Input is translated into data for various device
  types (digital, analog, glove, etc.)
• They are API-specific (OpenGL, Performer)

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PySim

• First custom simulator plug-in
• Combines C and Python
• C plug-in loads Python modules that provide the
  actual simulator functionality
• This allows for rapid prototyping of simulators
  in an interpreted language (no recompiling)
• SimGrab is our prototype Python module that loads
  into PySim

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SimGrab

• Interactive controls for moving the head and wand
• Map 2D mouse input to 3D space
• Buttons and sliders
• Semantic controls click and drag behavior

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Avatar Manipulation

• Select avatar body or green wand with the mouse
• Manipulator controls appear
• Active control is highlighted when under the
  mouse
• Arm has constraints similar to human arm

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Demonstration
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Conclusions

• Wanted to create a better simulator interface for
  VR Juggler
• SimGrab eliminates syntactic input
• PySim allows rapid prototyping of new simulators
  in the Python language
• Demonstrates the functionality and usability of
  the VR Juggler simulator plug-in architecture

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Future Work

• Improve performance
• Enhance avatar inverse kinematics and constraints
• User study
• Addressing expert users
• Shortcuts for experienced users to improve
  interface efficiency