Do large objects appear to approach more slowly than smaller objects traveling at the same speed? If so then this might help explain the inordinately high accident rates involving large vehicles such as buses and trains. To test this, this study constructed an experiment using a 3D visual...

The focus of this project is the modification of a commercially available in-pavement warning signal that was evolved from one originally designed to indicate the presence of pedestrians in a crosswalk. We have proposed use of a similar device to provide warning to vehicles approaching a...

ITS innovations in California are likely to include automated systems for vehicle guidance. Such systems will supplant manual controls during certain types of vehicle operation. However, the alternative manual control must remain intact in the vehicle. Thus, epochs of automated-manual transition...

About one quarter million intersections in this country had, as of 1996, been fitted with traffic control signals. That number is increasing annually as urban sprawl and increased crowding lead to more traffic and to the need for more vigorous traffic control capability. Each intersection has an...

Designers are often asked to gauge the influence of an illuminant or a visual signal on the human eye in a particular application. It has long been known that physical measurement is insufficient for this purpose. This is, in part, because the human sense of vision is not equipped with a...

The initiatives known as the Intelligent Vehicle Highway System (IVHS) of the early 1990's, of the Automated Highway System and the Intelligent Transportation System of the middle 90's, and now USDOT's Intelligent Vehicle Initiative of 1998, have all created a climate for rapid advance in ground...

This paper will describe an encounter with, and a look at, an Audi. Observations and measurements of the output of its headlights serve to emphasize some things concerning the relation of photometry to its task. Photometry's task is to predict the visual effect of light. This paper focuses on...