Abstract
Purpose: Ho et al (2008, Psych Science) examined how changes in one material property – gloss – affect perception of a second – roughness — and v.v. We examine how perception of angular velocity is affected by the surface material – glossy or matte – of a rotating object. In this work we investigate the relationship between material and motion by looking at the effect of material properties on the perception of the angular velocity of rotating rigid 3D virtual objects. Methods: Objects were smooth, irregular shapes resembling potatoes rendered under a point light source. They were either shiny or matte and rotated at angular velocities between 60 deg/sec and 420 deg/sec. On each trial the subject saw a pair of rotating objects – one shiny, one matte – presented one after the other. The subject’s task was to judge which object in the pair rotated faster. We used a staircase method to adjust the angular velocity of one object in each pair until it appeared to be rotating as rapidly as the other. Nine subjects completed the experiment (1 other subject was excluded due to lack of convergence in staircases). Results: The data reveal an overall bias towards perceiving matte objects to be rotating relatively faster than shiny (t7 = -2.8885, p = 0.0234). That is, if a matte and shiny object appear to be rotating at the same angular velocity, the matte object is objectively rotating more slowly. The bias was 34 degrees per second. Conclusion: We find a large effect of surface material on perception of angular velocity consistent with the findings of Kucukoglu, Fleming & Doerschner (2010, VSS) for linear motion.
Meeting abstract presented at VSS 2013