Prevention of drowsy driving by means of warning sound

Traffic accidents occur due to inattentive driving such as drowsy driving. A variety of support systems that make an attempt to prevent inattentive driving are under development. The development of a system to prevent drowsy driving using auditory or tactile alarm system is undertaken. It is essential to detect the low arousal state and warn drivers of such a state so that drowsy can be prevented. EEG (Electroencephalography) was used to evaluate how an arousal level degraded with time for eight participants under a low arousal level. Mean power frequency (MPF) was calculated to evaluate an arousal level. The value of MPF was compared between high and low arousal levels. The difference of arousal effect among four warning sounds was examined. As a result, there was no significant difference of arousal effect among four alarm sounds. The alarm sound was found to temporarily heighten participants' arousal level

Usability of Site Map in Web Design – Design of Site Map that is Friendly to Older Adults-

The information or data for Web page design that is useful, in particular, to older adults was provided in this study. The proper design of site map is necessary to enhance the usability and reduce the number of getting lost in Web navigation especially for older adults. However, no design guideline on what site map is proper exists. The usability of six types of site maps was compared as a function of age. The six types of site maps included (1) vertical tree type, (2) horizontal tree type (A), (3) horizontal tree type (B), (4) table type, (5) radial type, and (6) itemized type. The usability was evaluated using search time, subjective rating of usability, and eye movement characteristics (fixation duration and fixation number). The age affected the evaluation measures. The horizontal type (B) was found to lead to faster search time and fewer fixation numbers. Moreover, this type of site map was found to make the difference of search time, fixation number, and fixation duration between young and older adults smaller. The result indicated that the vertical arrangement of site map, especially horizontal type (B) was proper for both young and older adults, and this should be incorporated into the Web page design guidelines. The results can be utilized as a universal design guideline for providing a site map that is friendly to both young and older adults

Evaluation of Automotive Control-Display System by means of MentalWorkload

The effects of age, task difficulty on performance and mental workload were discussed in order to provide design guideline of automobile display that is friendly to older adults from the viewpoints of mental attention, speed and accuracy. A dual-task experiment was conducted in which the primary task was first order tracking. The secondary tasks included selection of function (easy condition), and control of an air conditioner, the operation of a radio, and the operation of a CD/MD (difficult condition), by means of a steering wheel mounted switch. The display was arranged in front of a participant. Age affected the performance measures and heart rate variability (HRV). As for the young adults, the task completion time did not differ significantly among easy and difficult (one-, two-, and three-layered) conditions. The performance of older adults was affected by task difficulty. The HRV measures such as CV (coefficient of variance) and RRV8-3 during the task showed different tendency between young and older adults. As for the young group, the HRV measures did not differ significantly between the four task levels (easy, one-, two-, and three-layered). This confirmed that the task difficulty did not induce different mental workload to young adults. On the other hand, as for the older adults, the HRV measures tended to increase with the increase of task difficulty. Although it appears that mental workload was lessened with the increase of task difficulty, such an interpretation was contradictory to the results on performance. This phenomenon was interpreted that the difficult task condition was overloaded for older adults, and was beyond the limit of mental effort. Based on the results, it could be concluded that the difficult task condition is not proper for older adults

Effectiveness of the menu selection method for eye-gaze input system - Comparison between young and older adults -

Although the opportunity of older adults to use personal computer is increased more and more, the operation of a personal computer with a mouse is very annoying for older adults who cannot move his or her arm smoothly and effectively due to declined motor function. An attempt to move a cursor by an eye-gaze input system has been carried out as one solution to this problem. Until now, a menu selection method suitable for an eye-gaze input system has not been clarified. In this study, an effective menu selection for the eye-gaze input system was identified as a basic design parameter to develop a Web browser using an eye-gaze input system. Concretely, a menu selection method, that is, improved quick glance menu selection (I-QGMS) was proposed. The effectiveness was evaluated by means of the pointing accuracy, the pointing time, and the psychological rating on usability. On the basis of the evaluation experiment, the proposed I-QGMS was found to be effective especially for older adults

Effects of location of information presentation in pedestrian detection system on visibility and performance

A few pedestrian warning systems for automobiles are in practical use. It has not been clarified where is best suited for the location of pedestrian information presentation. The most effective location of information presentation in pedestrian detection system was investigated. In other words, the location that assured the fastest cognition of pedestrian information was clarified. The locations of information presentation in pedestrian detection system were front glass, front display of cockpit module, and left side display of cockpit module (like car navigation system). The participants were required to pay attention to the predetermined front area as well as the randomly presented pedestrian information while carrying out a virtual driving task (tracking task) and a secondary switch pressing task such as selection of wiper function. We also investigated the effect of alarm sound presented to the participants together with the visual pedestrian information on the cognition time of pedestrian information. As a result, the front glass was most suitable for the presentation of pedestrian information. The presentation of pedestrian information to the front glass led to high visibility and faster pedestrian cognition time

Design method of Cockpit module in consideration of switch type, location of switch and display information for older drivers

In this paper, the effects of switch type, location of switch, and display information on the primary driving task and the secondary switch operation were investigated. The switch type included an integrated and a non-integrated switch. These switches were located on the front left, on the left side, or around a steering wheel. We prepared three displays with different display information (2.0, 4.1, and 5.9 bit). The tracking error, the mean operation time, the percentage of correct answer, NASA-TLX mental workload, and the subjective evaluation of usability were measured in order to analyze how these measures were affected by experimental factors above. The results suggested that young adults are better than older adults at both abilities on processing displayed information and operating switches. The integrated switch was found to affect driving performance than the non-integrated switch, and had little influence on switch operation. In addition, it was clarified that the switch located around a steering wheel had little influence on driving performance. Low display information was also found not to affect the performance

Visual information processing characteristics of drivers in prediction of dangerous situation - Comparison among novice, expert and non-licensed person -

The aim of this study was to examine the difference of visual information processing in KYT (Kiken Yochi Training) among novice, expert and non-licensed persons. In KYT tasks, participants were required to search for a potentially dangerous part using a static image under driving situations. The location of fixation point and the time series change of eye gaze were measured using an eye camera. In order to detect the difference of visual information processing among three groups above, an important area that the participants must pay attention to with the highest priority was set for each static image. The time until the eye gaze fixates to the important area, and the ratio of the fixation time to the total search time were detected. Using these measures, the difference of visual information processing among three groups was clarified. Moreover, for novice and non-licensed participants, it was also explored whether a lecture related to KYT would improve the efficiency of visual information processing. The time until the eye gaze fixates to the important area was longer for the non-licensed participants than for the experienced participants. The learning effect by means of a KYT lecture was also observed

Basic study on relationship between SI, EI and human error characteristics

Recently, accidents or scandals due to organizational violation-based error frequently occur. One of the causes might be maladjustment to environmental changes surrounding organization from relief to global society. In this study, the following proposition was hypothesized: Social intelligence (SI), ability to evaluate appropriately the reliability of others, ability to carry out communication smoothly in organization, and emotional aspects (behavior on the basis of emotion or reasonability) are important factors and keys to prevent violation-based organizational error. A questionnaire which included items related to social intelligence (SI: social awareness and social facility), emotional intelligence (EI), ability to evaluate the reliability of others, ability to communicate smoothly in organization, behavioral characteristics (emotional- or reasonability-based behavior), and ability to make decisions and judge situations. An attempt was made to verify the hypothesis above by a survey using the questionnaire

Fundamental study for constructing a system to assist the left visual field of older drivers - Effectiveness of the alternative of the left front side-view mirror by the central visual field -

The purpose of this paper is to establish the basics of the systems that assist visibility of the left visual field for older drivers. The display was located either the left which corresponded to a left side mirror, or within the central effective visual field. Participants performed multiple tasks where tracking task using a steering wheel was a primary task, and judgment of situations using a left or front display was a secondary task. How the display location affected the judgment performance was explored for both young and older adults. We counted the number of the warning during the tracking task and measured the percentage correct reaction to displayed stimulus and reaction sensitivity. We investigated how these measures ware affected by age and display location. Mean warning number during the tracking tasks, the percentage correct recognition of situations and d' was affected age and display location. The central display was found to increase the percentage correct recognitions of situations