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An airbag system for motorcycle applications was developed and commercially released in 2006 based on many research results on that system. In the airbag system, the bag should be supported during the period in a collision. The previously developed system employed a configuration in which the airbag was supported by the structures of the motorcycle, such as the instrument panel and the surrounding structures. These structures receive the reaction force to hold the airbag during a crash to properly absorb the rider's kinetic energy. Meanwhile, the previous system requires a larger area for these reaction structures and is applicable only to the motorcycles that can provide the area. To overcome this limitation, we propose an airbag system employing another concept. In this concept, the airbag does not use its vehicle structures as reaction structures but uses the structures of an opposing vehicle, such as doors and/or pillars.

In the near future, the LED headlamps will be available in the market by improvement of the technique. There are some methods that can produce white light using LEDs. Probably, we think most generally method is using blue LED and yellow phosphor. But, spectral power distribution (SPD) of this type of white LED is much different from traditional white light that is produced by halogen or HID. This type of the white LED has poor spectral power in long wavelength region and much spectral power in short wavelength region. So, the white light by LED might have color-rendering problem. On the assumption that automotive head lamps with white LED and halogen, the human color perception and recognition under wide range of illuminance conditions from photopic to mesopic was measured, using categorical color naming method and elemental color scaling method. As the result of this measurement, stability of categorical color naming was lower under lower illuminance level with both light sources.

The present study was designed to investigate the customer preferences related to headlights, as measured by J.D. Power and Associates 1998 Initial Quality Study (IQS) - (“Headlights not aimed properly” question). We investigated beam patterns that ranged from high to low customer preference. As a result of our investigation, we have developed guidelines for desirable beam patterns for the U.S. market in terms of the sharpness of the cutoff, the foreground brightness, and the total flux value.

The present study was designed to investigate the advantage of a new headlamp system. This so-called smart headlamp system involves headlamps with variable beam patterns. We analytically investigated visibility for the driver and glare to other road users under several conditions including curves and straight roads. We conclude that the smart headlamp system provides overall benefits.

This study evaluated the relative effects of horizontal and vertical misaim of low-beam headlamps. The approach involved analyzing light-output matrices of 150 production low beams, manufactured for sale in the U.S., Europe, and Japan. The specific analysis involved computing, for 225 locations in the central part of each beam pattern, the ratios of nominal intensity and intensity for vertical and horizontal misaim of up to 1.5°. The ratios greater than 1 log unit were considered to be of practical significance in terms of changes in visual performance and discomfort glare, and those greater than 0.5 log unit of likely significance. Only changes relative to visual performance and glare under nominal aim were considered; absolute levels were not examined. Furthermore, simultaneous horizontal and vertical misaims were not considered.

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.

Body-color brake lamps are lamps that in their off state match the body color of the car. When energized, all body-color lamps, as well as conventional lamps, appear bright red. The speed of response to a body-color brake lamp may differ from the speed of response to a conventional lamp for two reasons. The first is that the difference between off-and on-state luminances varies primarily with off-state luminance. When the difference is larger than for the conventional lamp, the increased luminance contrast may speed reaction time. The other reason that responses for the two types of lamps may differ is the greater chromaticity contrast that body-color lamps have between their on and off states. This study separately evaluated the effects of luminance contrast and chromaticity contrast for body-color brake lamps.

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.

Using a higher order vortex panel method, three dimensional free wake analyses for a rotor in hover are carried out. The purpose of this paper is to propose new methods being able to incorporate wake deformations due to wake-ground interactions into performance predictions. Both rotors at isolated and at close proximity to arbitrary shaped ground surfaces are investigated. The blade is modeled as a lifting surface with one row of cells (equivalent to Weissinger's L model). The wake is divided into the adjoining, near and far regions. The ground is approximated by the quadrilateral panels. The first two regions of the wake are modeled by triangular shaped panels with linear vorticity distribution which are adopted by their flexibility for roll up deformations of the wake. A semi-infinite vortex cylinder with the constant radius is substituted for the far wake to avoid instabilities of the wake geometry.