November 2002
Volume 2, Issue 7
Free
Vision Sciences Society Annual Meeting Abstract  |   November 2002
Velocity dependence of optic flow strategy for steering and obstacle avoidance
Author Affiliations
  • Philip W. Fink
    Brown University, USA
  • William Warren
    Brown University, USA
Journal of Vision November 2002, Vol.2, 430. doi:10.1167/2.7.430
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Philip W. Fink, William Warren; Velocity dependence of optic flow strategy for steering and obstacle avoidance. Journal of Vision 2002;2(7):430. doi: 10.1167/2.7.430.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Recent research has suggested that both egocentric direction and optic flow are used to guide locomotion to a goal (Warren et al., 2001; Wood, et al., 2001; Harris & Carre, 2001). However, the contribution of the optic flow strategy should depend on the velocity of the flow field. In a pair of experiments, we examined the relative contributions of egocentric direction and optic flow while varying the effective flow field velocity. Participants were tested in a 12 m × 12 m virtual environment, wearing a head-mounted display (40 deg H × 60 deg V), with head position measured by a hybrid sonic/inertial tracking system. To dissociate the two strategies, the heading direction specified by optic flow was shifted 10 degrees (randomly to the L or R) from the actual direction of walking. In the first experiment, participants walked to a target located 9 meters away in physical space, placed at one of three angles (3, 8, or 13 degrees) away from the initial heading. Velocity of optic flow was manipulated by changing the “gain” between physical and virtual space so that the flow velocity was either 0.5, 1, 2, or 4 times the physical walking speed. Preliminary results indicate that the optic flow strategy was more dominant at higher flow velocities than at low velocities. In experiment 2, participants again walked to a target located 9 meters away in physical space while avoiding one to three obstacles en route, in the same visual gain conditions. Fajen & Warren's (submitted; VSS 2001) dynamic model of steering and obstacle avoidance will be expanded to incorporate both egocentric direction and optic flow strategies.

NIH EY10923, NSF LIS IRI-9720327

Fink, P. W., Warren, W.(2002). Velocity dependence of optic flow strategy for steering and obstacle avoidance [Abstract]. Journal of Vision, 2( 7): 430, 430a, http://journalofvision.org/2/7/430/, doi:10.1167/2.7.430. [CrossRef]
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×