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LEDs have been developed that are suitable for use in automotive signal lamps. As signal light sources, LEDs have a number of advantages, among which are faster rise times, long life, flexibility in lamp size and shape, and the possibility of unique modes of presentation that may improve signal performance. The purpose of the research described in this paper was to examine driver preferences and response time to unique stop and turn signal presentations using LED sources. The results suggest that subjects preferred some of the signal modes to present-day configurations, and responded faster to them under a variety of conditions.

An evaluation was conducted of a mechanical beam switching system that may be appropriate for use with HID lamps. Subjects rated the adequacy of beam change time at several rates, compared with an electrical beam changing system. The results indicate that the subjects rated the mechanical and electrical systems the same, at the shortest change time for the former. Longer change times elicited poorer ratings for the mechanical system. The change from low to high beam was rated better than the change from high to low beam in the mechanical system. This difference was statistically significant at the two slower change rates investigated.

In two experiments, we examined the possibility that rearview mirror reflectivity influences drivers' perceptions of the distance to following vehicles. In the first experiment, subjects made magnitude estimates of the distance to a vehicle seen in a variable-reflectance rearview mirror. Reflectivity had a significant effect on the central tendency of subjects' judgments: distance estimates were greater when reflectivity was lower. There was no effect of reflectivity on the variability of judgments. In the second experiment, subjects were required to decide, under time pressure, whether a vehicle viewed in a variable-reflectance rearview mirror had been displaced toward them or away from them when they were shown two views of the vehicle in quick succession. We measured the speed and accuracy of their responses. Mirror reflectivity did not affect speed or accuracy, but it did cause a bias in the type of errors that subjects made.

The highest fatal traffic accident rate occurs on a curved road at nighttime. The “Active Headlight (AHL)” system developed by Honda R&D and Stanley Electric is the system that the beam pattern of the headlamp changes and more headlamp light is distributed toward a curve direction. The AHL system can direct alighttoward a curve before the vehicle enters a curve by using road information from a navigation system. When the AHL system moved in nighttime, visibility on curves and stability of driving were improved and glare to an oncoming vehicle was acceptable.

Safety concepts are essential to conform to functional safety standard ISO 26262 for automotive products. Safety requirements, which are a part of safety concepts, shall be satisfied by products to avoid hazards by vehicles to maintain their safety. Incompleteness of safety requirements must be avoided in deriving parent requirements to its children. However, measure for checking is only reviewing when the safety requirements are described in a natural language. This measure for checking is not objective or stringent. We developed a specification technique written in formal notation that addresses some of the shortcomings of capturing safety requirements for verification purposes. Safety requirements in this notation are expressed in goal tree models, which originate from goal-oriented requirement engineering Knowledge Acquisition in autOmated Specification (KAOS). Each requirement is written with propositional logic as the node of a tree.