title: Viewpoint animation with a dynamic tether for supporting navigation in a virtual environment.
abstract: OBJECTIVE
  This study examined the concept of dynamic viewpoint tethering for enhancing performance in 3-D avatar control tasks.
  
  
  BACKGROUND
  Dynamic viewpoint tethering refers to a viewpoint animation technique that couples a display viewpoint to a controlled avatar through a virtual tether. A dynamic tether, modeled as a mass spring damper system, can potentially generate desirable viewpoint behavior because of its ability to produce frequency-separated viewpoint responses. This study investigated the impact of a tether's rigidity and damping properties on users' navigational performance.
  
  
  METHODS
  Twelve participants took part in a simulated 3-D aerial navigational task. Performance was evaluated with respect to local guidance and global awareness.
  
  
  RESULTS
  Root mean square error scores revealed a decrease in local guidance performance when (a) the tether was either severely underdamped or overdamped and (b) the tether's rigidity approached either zero or infinity. In addition, (c) global performance was better for higher-frequency forcing functions.
  
  
  CONCLUSIONS
  Critical damping and medium rigidity can be optimized during design for enhancing users' navigational efficiency.
  
  
  CONCLUSIONS
  Guidelines generated from this study support future viewpoint design in interactive virtual reality applications.
authors.affiliation: Defence R&D Canada-Toronto, 1133 Sheppard Ave. West, Toronto, ON M3M 3B9, Canada. wenbi.wang@drdc-rddc.gc.ca
authors.forename: Wenbi
authors.initials: W
authors.lastname: Wang
authors.forename: Paul
authors.initials: P
authors.lastname: Milgram
mesh_terms: D001359:Aviation / Q000295:instrumentation; D003198:Computer Simulation; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation; D008297:Male; D013647:Task Performance and Analysis; D014584:User-Computer Interface; D014796:Visual Perception