Navigation

Navigation is an area of psychological study influenced heavily by the pioneering work of the psychologist Edward Tollman and his students at Berkley in the '40s. Tollman showed that rats used mental maps of the environment to perform rather amazing navigational feats such as shortcut taking and escape route planning. A key argument was based on the fact that rats showed so-called incidental learning. It was shown that rats took in information about many aspects of the environment that were not necessary to the performance of the task they were trained on.

A paucity of data addresses how humans navigate in virtual environments, but it is clear that navigation behaviors can make a big difference in the feeling of presence. There is a general consensus among VR researchers that most users end up lost in space. If the goal is to get the user immersed in the environment, it is worth the effort to either find or develop the best navigational behavior possible. A marginally realistic navigational behavior will likely include free ranging ability, a walking semantic (for example, a slight bounce as would be experienced in real walking), gravity, and collision avoidance.

The degree of attention that the developer needs to give the issue of navigation is strongly dependent on the application. Many applications only need to have a 3D representation of the product or visualization and don't require navigation. Other applications are all about navigation. Examples include a 3D shopping mall, 3D chat rooms, and first person shooter games. What makes or breaks a virtual experience in a navigational application is the quality of the spatial experience.

Free Ranging Navigation

Except when restricted by walls and other barriers, humans and other animals have a degree of free range in their natural settings. Although animals do indeed tend to travel in paths, they also tend to stop and look around. Interestingly, rats have a visual field of nearly 300° and therefore take in data about the environment all around them. Humans and other primates appear to be more dependent on the view directly in front of them.

Humans often move their heads 60-100° in plane while walking forward and then make larger movements during stops. There is also a slight out of plane movement due to steps. Turning around 360° is always a possibility but is not usually part of goal directed movements.

It is often the case that the environment also tends to guide the user during navigation. A good navigational utility would force the user back toward the middle of a hallway should the user get too close to an impermeable wall, for example.