In-vehicle information systems (IVIS) can provide useful information to support the driving task, reduce stress and make a journey more comfortable. A few brief glances to an IVIS are not likely to have a significant effect on safety. However the visual distraction caused by some in vehicle systems that require longer and more frequent glances is of concern. Occlusion is a technique that can be used to assess the visual distraction associated with operating an in-vehicle information system (IVIS). The technique is used for simulating the shift in visual attention between the driving scene and the IVIS. This is done using a shutter to hide and expose the IVIS from view, or goggles that also block or reveal the visual scene (the IVIS). The amount of time (duration and frequency) that the IVIS is visible or occluded (blocked from view) is controlled during occlusion. The basic idea is to investigate whether in-vehicle tasks can be carried out in short bursts of visual attention towards a display screen (typically 1 to 2 seconds). This literature review was carried out to identify previous research on the occlusion technique as a measure of the distraction imposed by IVIS. A number of issues need to be considered when developing a standard protocol with which IVIS might be assessed. The review considers the technique in terms of issues such as shutter open/closed times, and the variables against which the system should be assessed. In addition, issues such as training, sample demographics, test environment, number of trial repetitions, impact of primary distracter tasks and how to deal with system response delays are considered. (Author/publisher)
Abstract