Abstract
Little is known about the role of stereopsis in locomotion activities, such as continuous walking and running. While previous studies have shown that stereopsis improves the accuracy of lower limb movements while walking in constrained spaces, it is still unclear whether stereopsis aids continuous locomotion during extended motion over longer distance. We conducted two walking experiments in virtual environments to investigate the role of binocular vision in avoiding virtual obstacles and traversing virtual gaps during continuous walking. The virtual environments were presented on a novel projected display known as the Wide Immersive Stereo Environment (WISE) and the participant locomoted through them on a linear treadmill. This experiment setup provided us with a unique advantage of simulating long-distance walking through an extended environment. In Experiment 1, along each 100-m path were thirty virtual obstacles, ten each at heights of 0.1 m, 0.2 m or 0.3 m, in random order. In Experiment 2, along each 100-m path were thirty virtual gaps, either 0.2 m, 0.3 m or 0.4 m across. During experimental sessions, participants were asked to walk at a constant speed of 2 km/h under both stereoscopic viewing and non-stereoscopic viewing conditions and step over virtual obstacles or gaps when necessary. By analyzing the gait parameters, such as stride height and stride length, we found that stereoscopic vision helped people to make more accurate steps over virtual obstacles and gaps during continuous walking.
Acknowledgement: NSERC Discovery Grant, Canadian Foundation for Innovation, and the CFREF Vision Science to Applications (VISTA) program