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Non-planar driver's side rear-view mirrors provide a wider field-of-view than planar mirrors, but produce a minified image. A field experiment was conducted to measure the performance of drivers when making lane change decisions based on mirror information. Four mirror types were included: a planar mirror, a spherical convex mirror and two aspherical mirrors (radius of curvature 1400 and 2000 mm, respectively). Non-planar mirrors improved drivers' detection of adjacent vehicles due to wider fields of view. Drivers' experience with non-planar mirrors did not generally compensate for the negative effect of accepting smaller gaps, with the exception of drivers who were accustomed to spherical convex mirrors. No increase in the visual workload was required to process information in non-planar mirrors. The conclusion was that the relative benefits of non-planar mirrors should be greater than the negative effects.

Drivers of commercial vans and delivery trucks (e.g, step vans) which do not have rear windows have limited visibility of the area directly behind the vehicle. Many but not all of these vehicles use a high-mounted convex mirror in the rear of the vehicle to give drivers a view of what is directly behind the vehicle. The National Highway Traffic Safety Administration (NHTSA) was interested in obtaining additional information about the performance of these rear cross-view mirrors. While such mirrors provide drivers with a view to the rear, this view is necessarily distorted and minified. This study, performed for NHTSA, quantified this minification and distortion and also measured the ability of drivers to use the mirrors to detect and recognize objects in the rear.

A study is being conducted to investigate the effects of driver’s side rearview mirror types (either flat or nonplanar mirrors) on driver behavior. The study consists of a survey of mirror characteristics, interviews and questionnaires and a field experiment. The present paper gives the results of the first phase of exploratory interviews. A structured list of questions was used to gather extensive information on mirror use habits, on problems drivers have experienced, on their awareness of mirror characteristics and on background variables. The 47 respondents were categorized by age group (younger / older drivers) and driver’s side mirror type (flat, convex, aspherical). The results of this exploratory phase serve as a basis for a revised questionnaire to be used for a large sample of drivers.

The Ford CHESS computer program was used to evaluate headlamp performance as a function of various influencing factors such as beam pattern, aim, and overall intensity. The degree to which the model was sensitive to headlamp, driver, and environmental variables was assessed. The results showed that only small increases in performance could be achieved by beam pattern modifications, improved aim, and increased overall intensity. Part of the difficulty in identifying performance improvements was found to be the low sensitivity of the CHESS figure of merit to changes in beam photometrics. Suggestions are made for upgrading the CHESS evaluation methodology to make the performance metrics more sensitive to differences in beam design.

This paper surveys the literature on motor vehicle headlighting and its influence on the ability of drivers to avoid accidents. The review identifies the key relationships between headlamp design characteristics and driver and environmental factors. The major safety problems associated with headlighting are discussed, and issues needing the attention of the research community are identified.

Difficulties of measuring safety problems related to human factors aspects of vehicle controls and displays are discussed and illustrated with examples. A review of National Highway Traffic Safety Administration (NHTSA)-sponsored control/display research dealing with some of these problems is presented. The review describes the objectives, methodology, key findings, and application of the results of the research. Finally, future research needs are outlined.