Effects of scale change on distance perception in virtual environments

Abstract

We conducted two experiments to investigate effects of scale changes on distance perception in virtual environments. In both experiments, participants first made distance estimates with feedback in a virtual tunnel (adaptation) and then made distance estimates without feedback in a differently sized environment (test). We examined two types of scale changes. In the "Tunnel Scaled" conditions, only the size of the tunnel changed from adaptation to test. In the "All Scaled" conditions, both the tunnel and target sizes changed from adaptation to test, along with the distance between the targets. Both experiments were carried out in an HMD. In the first experiment, participants made distance estimates by moving to targets via a joystick. In the "All Scaled" condition, participants overshot relative to adaptation when going from a large to a small environment, and they undershot relative to adaptation when going from a small to a large environment. We found almost no effects of scale change in either direction when only the tunnel was scaled at test. Experiment 2 was the same except that subjects made distance estimates via blindfolded walking. The pattern of results was the same, though the size of the overshoot/undershoot was attenuated. The discussion focuses on explanations for the effects of scale changes on distance estimates.