Perceived distance of targets in convex mirrors

We investigated the perceived distance of targets in convex and plane mirrors. In Experiment 1, 20 subjects matched the distance of targets in a real scene to the distance of a virtual target in different mirrors. The matched distances were much larger for convex mirrors than for a plane mirror. In Experiment 2, 20 subjects viewed two targets in a mirror and adjusted their own positions so that the distance to the closer target was perceived to equal the distance between the targets. The mean distance to the closer target was smaller for the convex mirrors than for the plane mirror. In Experiment 3, 20 subjects adjusted the position of a target so that the distance to it in a mirror was perceived to equal the distance designated by the experimenter. The best-fitting power functions showed that the scaling factors were larger for the convex mirrors than for the plane mirror, but the exponents were smaller for the convex mirrors than for the plane mirror. It is suggested that distance in the convex mirrors was perceived to be larger than in the plane mirror, and that the growth of perceived distance in the convex mirrors was slower than in the plane mirror.     

Secondary task engagement and disengagement in the context of highly automated driving

During highly automated driving (level 3 automation according to SAE International, 2014) people are likely to increase the frequency of secondary task interactions. However, the driver must still be able to take over control within a reasonable amount of time. Previous studies mainly investigated take-over behavior by forcing participants to engage in secondary tasks prior to take over, and barely addressed how drivers voluntarily schedule secondary task processing according to the availability and predictability of automated driving modes. In the current simulator study 20 participants completed a test drive with alternating sections of manual and highly automated driving. One group had a preview on the availability of the automated driving system in upcoming sections of the track (predictive HMI), while the other drivers served as a control group. A texting task was offered during both driving modes and also prior to take-over situations. Participants were free to accept or reject a given task, taking the situational demands into account. Drivers accepted more tasks during highly automated driving. Furthermore, tasks were rejected more often prior to take-over situations in the predictive HMI group. This was accompanied by safer take-over performance. However, once engaged in a task, drivers tended to continue texting even in take-over situations. The results indicate the need to discriminate different aspects of task handling regarding self-regulation: task engagement and disengagement.     

The effects of safety knowledge and psychological factors on self-reported risky driving behaviors including group violations for e-bike riders in China

ObjectivesIt is unknown that how safety knowledge and psychological factors affect e-bike rider safety. Also, group violation behaviors, which are commonly observed in the field, have been rarely examined for e-bike riders in China. In this paper, the effects of safety knowledge and psychological factors on self-reported risky driving behaviors including group violations were examined.MethodsA questionnaire was developed to acquire information of e-bike riders in Guilin, Guangxi Province. Explanatory factor analysis was used to examine the reliability of the questionnaire and exclude redundant measurement items. Then, a Structure Equation Model was developed to examine the relationships among safety knowledge, safety attitude, risk perception and risky driving behaviors. After that, multiple regression models were fitted to examine the effect of safety knowledge on each type of risky driving behavior, as well as factors associated with group violations. At last, ANOVA tests were conducted to identify significant differences among e-bike rider groups in safety knowledge, safety attitude, and risk perception.ResultsSafety knowledge was found significantly associated with risky driving behaviors for e-bike riders in China, including aggressive driving, erroneous driving, and group violations. E-bike riders severely lack safety knowledge, especially that of traffic rules, including unmarried riders, under-educated riders, riders without driver’s license, younger riders, and riders with little riding experience. Group violations were largely found among e-bike riders, and to be associated with safety knowledge of traffic rules, risk-taking attitude, and riding experience of e-bike riders.ConclusionsThe findings could add some new safety implication and be beneficial for developing safety policies and interventions for e-bikes.     

The influence of road familiarity on distracted driving activities and driving operation using naturalistic driving study data

This paper analyzed the influence of familiarity on the involvement of secondary tasks and driving operation using naturalistic driving study (NDS) data. Distracted driving activities were extracted from face videos captured in 557 trips, including 501 trips on familiar roads and 56 trips on unfamiliar roads. These trips were completed by 155 drivers using their own vehicles during daytime hours under good weather conditions. The data showed the frequency of distracted driving activities and duration time were higher on familiar roads compared to unfamiliar roads. More types of secondary tasks were found on familiar roads. Focusing on objects was the most common distracted driving activity on familiar roads. The average time drivers used to eat or drink was highest (8.67 s) on familiar roads. The time drivers spent checking their cell phone was high on both familiar roads and unfamiliar roads. Since driving operation is directly related to crash risk, this paper also analyzed the difference of driving operation on familiar roads and unfamiliar roads. The speed profiles were generated on well-known versus unfamiliar roads. It was shown that drivers were more likely to be speeding and select a short distance to deceleration near the intersections. The findings indicated that distracted driving phenomenon was more serious on familiar roads.     

Driving anger and its relationship with aggressive driving among Chinese drivers

Driving anger poses a serious threat to road safety. Increasing attention is being paid on this issue, with driving anger usually measured by a 14-item version of the Driving Anger Scale (short DAS). However, driving anger problem in China has received limited research attention and there is no corresponding Chinese version of the short DAS. This study adapted the short DAS for use with Chinese drivers and investigated the relationship between driving anger and aggressive driving with an Internet-based survey conducted to a sample of Chinese drivers. The Confirmatory Factor Analysis results showed that a three-factor DAS structure provided a good fit to the data obtained, with the three subscales used being hostile gesture, safety-blocking and arrival-blocking. The hostile gesture subscale and arrival-blocking subscale were positive predictors while the safety-blocking subscale was a negative predictor of aggressive driving. In China, the overall driving anger was lower but its association with aggressive driving was stronger, than that in western countries. These findings provide important insights into causes and consequences of driving anger for the development of effective strategies to reduce driving anger and to enhance road safety.     

背景音乐的节奏与歌词语言熟悉程度对驾驶行为和眼动的影响

摘要：采用3D模拟驾驶情景结合眼动技术探讨音乐节奏和歌词语言熟悉程度对驾驶行为和眼动规律的影响,研究结果表明：（1）驾驶经验对驾驶行为及眼动影响显著,新手与老手相比速度更慢、错误数更多;（2）音乐节奏对驾驶速度、眼跳和垂直搜索广度影响显著,快节奏与慢节奏相比,驾驶速度更快、平均眼跳距离更短、垂直搜索广度更短;（3）歌词语言熟悉程度对驾驶速度、错误数和平均注视时间影响显著,熟悉语言与陌生语言相比,驾驶速度更慢、错误数更多、平均注视时间新手更长,老手无影响。（4）节奏与语言共同影响驾驶过程中的水平搜索广度,陌生语言时快节奏的水平搜索广度高于慢节奏,熟悉语言时快节奏的水平搜索广度低于慢节奏。通过本实验,建议驾驶员在选择音乐时选择陌生语言歌词的音乐,音乐节奏则可视情况而定。     

Motivating signage prompts safety belt use among drivers exiting senior communities

Senior drivers are vulnerable to automobile crashes and subsequent injury and death. Safety belts reduce health risks associated with auto crashes. Therefore, it is important to encourage senior drivers to wear safety belts while driving. Using an AB design, replicated five times, we evaluated the short- and long-term effects of a sign with the message "BUCKLE UP, STAY SAFE" attached to a stop sign at the exits of five different senior communities. Safety belt use was stable during two pretreatment assessments averaged across the five sites and 250 drivers (72% and 68% usage), but significantly increased following installation of these signs (94% usage). Six months after installation of the signs, the effect persisted (88% usage). Use of such signs may be a cost-effective way of promoting safety belt use.     

Comprehensive driving assessment: neuropsychological testing and on-road evaluation of brain injured patients

The study investigates the correspondence between neuropsychological test results and on-road driving performance among 55 patients with a CT-verified brain damage or documented neurological disorder (cerebrovascular accident: 43, traumatic brain injury: 5, multiple sclerosis: 4, other: 3). 5 patients showed unimpaired test profiles and passed the on-road evaluation. 18 patients showed severe neuropsychological deficits contrary to driving and were not recommended for on-road evaluation. Of the remaining 32 patients with some neuropsychological deficits, all 100% in the minor impaired group (n = 8) passed the driving evaluation, compared to 69% in the mildly impaired (n = 16) and 38% in the moderately impaired group (n = 8). Measures of reduced visuoconstructive ability, reaction time, visual attention, and awareness of cognitive impairments, were found to discriminate between groups. It is concluded that neuropsychological assessment of targeted functions provide an ecological valid prediction of driving skill after brain damage, but that on-road evaluation is needed as supplement in cases with ambiguous test findings.