Walking in Augmented Reality: An Experimental Evaluation by Playing with a Virtual Hopscotch

A crucial aspect when interacting in augmented reality (AR) scenarios is having a stable and coherent perception of the virtual contents overlaid on the real world. This is particularly challenging when the task in the AR environments involves walking onto virtual paths on the floor. In this paper, we present two experiments, conducted in both real-world and cluttered conditions and in a laboratory setup, in which non-trained people were asked to play with a virtual hopscotch. We perform both a qualitative evaluation, by means of a self-assessment questionnaire, and quantitative measures, by capturing the 3D positions of the observers, which show errors in the perception of the hopscotchs layout. The obtained results suggest us that besides the known issues of pose estimation, also the mismatch between the intrinsic parameters of the mobile camera and the ones of the observer eyes could be investigated and taken into account to design effective AR systems.