Why Do We Bump into Things while Walking

Abstract

People have a certain likelihood of bumping into objects projecting into their walking route. Two experiments, using simulated bumping accidents with a flexible rod, attempted to test an hypothesis that the likelihood of bumping into an object is a positive function of the distance between that object and the axis of the effective visual field of the walking person. The data, described as anthropometric bumping likelihood profiles, supported this hypothesis as well as additional predictions based on it. These data have implications for the design of walking environments such as preferred heights for placing projecting objects which are differentially visible, the effects of floor conditions on these preferred heights, and the importance of determining the walking habits of people for that purpose.