Bunji Atsumi

Study of breath alcohol detector

A novel detector of breath alcohol for a driver has been developed. The detector has three features. A mouth piece is not required because drivers breath is introduced to the detector by a suction pump. The influence of fluctuations of drivers breath flow is extremely reduced by the calibration of alcohol concentration using a humidity change. The detector is able to measure breath alcohol concentration rapidly, and the measurement time is about 2 to 3 seconds. The excellent performance have been demonstrated both in breath alcohol simulation tests and in a drunken persons test.

Development of a new breath alcohol detector without mouthpiece to prevent alcohol-impaired driving

A new breath alcohol detector for a driver has been developed. A mouthpiece is not required for the detection because driverpsilas breath sample is captured by an electric suction fan of the detector. The influence of an arbitrary dilution of driverpsilas expiration is extremely reduced by the calibration of alcohol concentration, using an oxygen level of driverpsilas expired breath that is measured simultaneously with the alcohol content. The detector is able to measure breath alcohol concentration rapidly and easily, compared with the current breath alcohol detectors, which require a blowing through a mouthpiece. Good accuracy has been demonstrated in an experiment with the drunk subjects.

Quantitative analysis of muscular stress during ingress/egress of the vehicle

Recently elderly users have been increasing in number, and the ease of ingress/egress of the vehicle becomes an important issue. In this paper, a method of evaluating the muscular stress during ingress/egress using several MVC (maximum-voluntary-contraction) was proposed. Further MVC for elderly people was measured as well as for young people, and the increasing ratio of muscular stress for elderly people was made clear as compared with young people. Thus the necessity of an assisting tool for elderly people was confirmed quantitatively.

REQUIRED PERFORMANCE OF DISPLAY DEVICES IN CONSIDERATION OF VISUAL CHARACTERISTICS OF ELDERLY PEOPLE : ABOUT LUMINANCE AND CHARACTER SIZE

The vehicle display condition must be adapted to the visual characteristics of elderly people, because increasing elderly drivers are expected. In this study, the measurements of two visual characteristics were found–visual acuity for distance and muddiness of crystalline lens, and the effect on display condition due to visual characteristics was investigated. The results show that the display condition for elderly people should be as follows. The size of characters is extended. The luminance level in night conditions has a widely a adjustable level, and in daytime conditions is set at similar or slightly higher levels in comparison with young and middle aged drivers.

VISUAL DISTRACTION WHILE DRIVING : TRENDS IN RESEARCH AND STANDARDIZATION

One of the problems brought into focus by the development of navigation and other ITS devices is that the operation of such devices draws the drivers eye from the visual field where it belongs while driving and creates a visual distraction that may impede safety. The article provides background information and summarizes worldwide trends in research on accident rates, the special characteristics of visual behavior and the effects of visual distraction on drivers and vehicle behavior. It also reports on the state of ISO standardization efforts and related technological trends. Finally, it defines a number of topics for future research in the field of human engineering. Keywords: Driver distraction

Visual cognitive performance of elderly people: effects on reading time of age, character size and visual distance

In this study, we conducted two experiments on visual cognitive performance in reading an on-board information device. Experiment 1: The relation between the gazing time needed for reading and the number of Kanji characters displayed was investigated, as the number of characters was changed in three steps. The gazing time was divided into preparation time and information processing time. The unit information processing speed was calculated from the amount of information read divided by the information processing time. Experiment 2: The character size was changed between three conditions (large, middle and small), and visual distance was changed between two conditions (700 and 2000 mm). The gazing time was similar to that in experiment 1. The results from these experiments are applicable to the design of user-friendly information devices, taking into account the users age.

Evaluation of vehicle motion sickness due to vehicle vibration

Recently many studies have been presented for realizing a better riding comfort. Above all, efforts for reducing a vehicle motion sickness of occupants are still needed. Motion sickness is considered to be caused by various factors, for example, personal constitution, driving situation and vehicle vibration. In this paper, the characteristics of vehicle body vibration that influence motion sickness were examined and methods to estimate the motion sickness level due to vehicle vibration were proposed. The proposed methods were applied to verify the effects of the improved suspension system that is installed in recently developed vehicles.

Visual Characteristics of Elderly Drivers – Aging Effects on Visual Acuity and Glare Feeling

The objective of the study was to investigate age related effects on visual acuity and reflected-glare associated with daytime and nighttime driving conditions. Fifty-six participants (28 young, 28 old) recruited from Virginia Tech student population and Blacksburg Community were tested in the study. Landolts Circle Method was adopted to assess visual acuity under simulated daytime and nighttime conditions. Although, the age and distance main effects were found to be significant, no differences were reported among all the distances within the young group. The study also examined the effects of reflected headlamp glare on age and mirror types on the basis of angle of incidence, illumination-front-of-eyes and rating scores. The results indicated that with the same glare level (as measured by angle and illumination in front of the eye), elderly adults reported lower glare rating scores (i.e. worse feelings of glare). Furthermore, the young and elderly both reported lower De Boers rating scores for planar driver-side mirrors than non-planar driver-side mirrors. This result can have practical implications in reducing nighttime discomfort glare for both young and elderly.

Development of a New Breath Alcohol Detector without Mouthpiece to Prevent Drunk Driving

Breath alcohol interlock systems are used in Europe and the U.S. for drunk driving offenders. Although a certain effect has been revealed in the prevention of drunk driving, problems to be solved remain with commercialized detectors, i.e., a person taking the breath alcohol test must strongly expire to the alcohol detector through a mouthpiece for every test, more over the determination of the breath alcohol concentration requires more than 5 seconds. The goal of this research is to develop a device that functions suitable and unobtrusive enough as the interlock system. For this purpose, a contact free alcohol detector, which doesn’t require a long and hard blowing to the detector through a mouthpiece, has been developed as a tool available on board for the prevention of drunk driving. The detector consists of an electric suction fan, an alcohol sensor, and an oxygen sensor mounted in a gas flow passage. It doesn’t require a mouthpiece for the detection because driver’s expired breath is captured by the suction fan. The influence of fluctuations of the alcohol sensor signals caused by air mixing is extremely reduced by the calibration of alcohol concentration using an oxygen level of driver’s expired breath that is measured simultaneously with the alcohol content. The detector is able to measure breath alcohol concentration rapidly and easily, compared with the current breath alcohol detectors which require a blowing through a mouthpiece. Good accuracy has been demonstrated in an experiment with the drunk subjects.

Information Management and Human Factors for Multiple its Systems

This paper describes frameworks for the information management system from multiple ITS and non-ITS systems from the view of human interface and human information processing. This message management system will prioritize the information message, allocate the information item to different types of display device, and determine the presentation style and the timing for the message presentation.