Augmented reality and scene examination

Department of Electronic, Electrical and Computer Engineering Doctor of Philosophy by Sashah James Eftekhari The research presented in this thesis explores the impact of Augmented Reality on human performance, and compares this technology with Virtual Reality using a head-mounted video-feed for a variety of tasks that relate to scene examination. The motivation for the work was the question of whether Augmented Reality could provide a vehicle for training in crime scene investigation. The Augmented Reality application was developed using fiducial markers in the Windows Presentation Foundation, running on a wearable computer platform; Virtual Reality was developed using the Crytek game engine to present a photo-realistic 3D environment; and a video-feed was provided through head-mounted webcam. All media were presented through head-mounted displays of similar resolution to provide the sole source of visual information to participants in the experiments. The experiments were designed to increase the amount of mobility required to conduct the search task, i.e., from rotation in the horizontal or vertical plane through to movement around a room. In each experiment, participants were required to find objects and subsequently recall their location. In the first experiment, objects were presented with and without background details, i.e., virtual 3D objects against a black background or superimposed on the fiducial markers in the real environment. The findings suggest that even where the real world is not task-relevant, by offering cues to spatial position participants were helped to orient their own spatial frame of reference with incidental contextual information that helped the encoding of object identity (e.g., the synthetic tank is by the real plantpot). This effect was explored further by blocking stimuli into sets of 3, this resulted in enhanced performance but also hinted that an orientationonly frame of reference adds no value to recall performance unless supplemented with a visual frame of reference. Experiment 2 compared search and recall in virtual reality,