The effect of visual HMIs of a system assisting manual drivers in manoeuvre coordination in system limit and system failure situations

Ambiguous situations in traffic often require communication and cooperation between road users. In order to resolve these situations and increase cooperative driving behavior in situations of merging or turning left, manual drivers could be assisted by an advanced driver assistance system (ADAS) for cooperative driving. This simulator study investigated the behavior of drivers confronted with system limits and failures of such a system. The ADAS used in this study informed the driver about an upcoming cooperation situation and gave advice on how to behave (e.g. reduce speed, change lane). Two test situations were implemented: a system freeze and an unexpected event, which could not be detected by the system. In order to find the most fitting HMI solution, the place of presentation (head-up display (HUD) vs. instrument cluster) as well as the form of presentation (dynamic vs. symbolic) were varied. The results indicated that the most fitting HMI solution to support the driver in a complex coordinated driving situation is a dynamic HUD, mainly due to the positive effect on glance behavior. However, advantages of both forms of presentation were revealed, as each form of presentation increased the probability of recognition for one of the test situations. The fewest collisions took place with the dynamic form of presentation.     

Competence,equipment and behavioural adaptation on Norwegian winter roads: A comparison of foreign and Norwegian HGV drivers

There seems to be a widespread view that foreign lorry drivers’ lack of competence on Norwegian roads, especially related to winter driving, is a significant safety problem. It has, however, been suggested that foreign heavy goods vehicle (HGV) drivers perform better than expected on Norwegian winter roads, as they feel less safe than Norwegian drivers, and adapt by driving slower and more carefully. The aim of the present paper is twofold. First, we examine whether foreign HGV drivers in Norway actually have poorer competence on, training for, experience with and equipment for winter driving than Norwegian HGV drivers. Second, we discuss whether the expected negative effect of these safety challenges is mitigated, as foreign HGV drivers adapt their behaviours. We use four data sources to shed light on the aims: (1) interviews, (2) roadside inspections, (3) small-scale survey and (4) towing incidents. Our data support the hypothesis about behavioural adaptation, indicating that foreign HGV drivers experience winter driving as more difficult or unsafe, as they have supposedly less suitable vehicles and equipment, less experience, training and competence for winter driving. They are therefore more likely to get stuck while driving uphill on winter roads, supposedly as they drive more carefully and slower than Norwegian HGV drivers. Norwegian HGV drivers feel safer and more confident while driving on winter roads, because of their equipment and their experience.     

Younger drivers executive functioning and the relationship with experiencing signs of sleepiness

Young drivers are more likely to continue driving when experiencing signs of sleepiness and are over-represented in sleep-related crashes. Adolescence and early adulthood are characterised by comparatively poor executive functioning, and while previous research has demonstrated a link between poor executive functions and several risky driving behaviours, the relationship with sleepy driving is not well understood. Accordingly, the first aim of the current study was to examine the association between executive functions and experiencing the signs of driver sleepiness in a sample of young adult drivers. Additionally, young drivers who have less experience with driving while sleepy, may attribute less importance to the signs of sleepiness as an indicator of underlying sleepiness level. To test this assumption (aim two), the impact of experiencing signs of sleepiness on perceptions of the importance of those signs was examined. Participants included 118 young adults aged between 17 and 25 years, who completed an online survey measuring experiences with the signs of sleepiness while driving, executive functions, and demographic characteristics. This sample of young adults reported having considerable experience with several signs of sleepiness (i.e., yawning, mind wandering, and difficulty keeping eyes while driving). A linear regression analysis found that the demographic variables of age and hours driven per week, as well as the executive function constructs of organization, strategic planning, and impulse control were associated with experiencing signs or sleepiness. Moreover, having experienced more signs of sleepiness was associated with an increased likelihood in rating those signs as important indicators of sleepiness. The current findings suggest both that several high-level cognitive processes as well as levels of experience with driving when experiencing signs of sleepiness contribute to young peoples’ sleepy driving.     

Eye movements predict driver reaction time to takeover request in automated driving: A real-vehicle study

For automated driving at SAE level 3 or lower, driver performance in responding to takeover requests (TORs) is decisive in providing system safety. A driver state monitoring system that can predict a driver’s performance in a TOR event will facilitate a safer control transition from vehicle to driver. This experimental study investigated whether driver eye-movement measured before a TOR can predict driving performance in a subsequent TOR event. We recruited participants (N = 36) to obtain realistic results in a real-vehicle study. In the experiment, drivers rode in an automated vehicle on a test track for about 32 min, and a critical TOR event occurred at the end of the drive. Eye movements were measured by a camera-based driver monitoring system, and five measures were extracted from the last 2-min epoch prior to the TOR event. The correlations between each eye-movement measure and driver reaction time were examined, and a multiple regression model was built using a stepwise procedure. The results showed that longer reaction time could be significantly predicted by a smaller number of large saccades, a greater number of medium saccades, and lower saccadic velocity. The implications of these relationships are consistent with previous studies. The present real-vehicle study can provide insights to the automotive industry in the search for a safer and more flexible interface between the automated vehicle and the driver.     

Driving anger scale validation: Relationship of driving anger with the aberrant driving behaviour of truck drivers

Truck-related accidents in China have substantially increased. Truck driver safety issues have elicited considerable attention from transportation safety researchers. Driving anger is one of the most important factors that influence driving behaviour. However, little knowledge about the driving anger of truck drivers was available in the relevant literature. This study aimed to (1) provide empirical data about the driving anger of truck drivers, (2) examine the factor structure and psychometric properties of the driving anger scale (DAS) with a sample of truck drivers and (3) explore how the driving anger of truck drivers predicts their aberrant driving behaviour. The three-part survey data from 475 randomly selected truck drivers were collected in this study. The self-reported aberrant driving behaviour that was measured with the driving behaviour questionnaire was predicted by the drivers’ DAS ratings. One-factor structure and three-factor structure of the DAS were tested for Chinese truck drivers. Results indicated that the one-factor structure of the six-item DAS was more suitable for truck drivers than the three-factor structure. The factor structure of the DAS for Chinese truck drivers was consistent with the structure of the original version by Deffenbacher, Oetting, and Lynch (1994). The internal consistency, convergent validity and criterion-related validity of the six-item DAS were acceptable. Driving anger amongst truck drivers can be used to predict their aberrant driving behaviour. This study identified several practical implications to reduce the driving anger of truck drivers and consequently improve their driving behaviour.     

Understanding and modelling risky driving behaviour on high-speed corridors

This study explores the relationships among various factors influencing risky driving behaviours, particularly on high-speed corridors (expressways). A total of 546 samples are collected from licenced drivers through an online survey. Exploratory factor analysis confirms the four-factor solution and the same is verified using confirmatory factor analysis. These factors are individual aberrant driving behaviour (violations and errors), risky driving behaviour performed by surrounding vehicles and dangerous manoeuvres due to prevailing road environment. Structural equation modelling is used to establish the relationships amongst the aforementioned factors. The results of the study describe that observed risky driving behaviour on expressways is mostly affected by drivers’ individual aberrant driving (γ = 0.62) followed by risky driving behaviour performed by surrounding vehicles (γ = 0.39) and least affected by the road environment (γ = 0.36). The individual driving behaviour is mostly affected by violations (γ = 0.47) followed by errors (γ = 0.38). Furthermore, differences in Driving Behaviour Questionnaire (DBQ) scales are analysed with respect to the demographic variables. Results suggest that male and young drivers report more violations than female and older drivers, respectively, however, female drivers are more error prone than male drivers. The findings of the study can be useful to identify the potential road safety countermeasures to improve the driving style as well as the driving environment.     

自动驾驶车中的人机信任

自动驾驶是当前智能汽车发展的重要方向。在实现完全自动化驾驶前, 驾驶员和自动驾驶系统共享车辆控制权, 协同完成驾驶任务。在该人-机共驾阶段, 人对自动驾驶系统的信任是影响自动驾驶中人机协同效率与驾驶安全的关键要素; 驾驶员对自动驾驶车辆保持适当的信任水平对驾驶安全至关重要。本研究结合信任的发展阶段与影响因素提出了动态信任框架。该框架将信任发展分为倾向性信任、初始信任、实时信任和事后信任四个发展阶段, 并结合操作者特征(人)、系统特征(自动驾驶车系统)、情境特征(环境)三个关键因素分析不同阶段的核心影响因素以及彼此间的内在关联。根据该框架, 信任校准可从监测矫正、驾驶员训练、优化HMI设计三类途径展开。未来研究应更多关注驾驶员和人机系统设计特征对信任的影响, 考察信任的实时测量和功能特异性, 探讨驾驶员和系统的相互信任机制, 以及提升信任研究的外部效度。     

A Survey on Driving in Clients With Mental Health Disorders

Few studies have explored driving issues in adult mental health. In this pilot study, 48 drivers were compared to 24 participants who had ceased driving, on their clinical and driving characteristics. Driving-related services offered to them were also documented. Participants who had stopped driving were more likely to be in-patients on antipsychotic or several medications. A third of the participants reported negative effects of their illness and/or medications on driving. Psychiatrists and occupational therapists offered assessments and recommendations related to fitness to drive to 30% of their clients using complementary approaches. This survey indicates that few drivers with mental health disorders receive driving-related services. More evidence-based practice guidelines are needed.     

Wellness Factors Decrease the Odds of Drinking and Driving Among College Students

The authors examined holistic wellness factors and drinking and driving behaviors among undergraduate students. Two factors of the Indivisible Self Wellness Model, the Coping Self and the Physical Self, decreased the odds of engaging in drinking and driving behavior.     

Suppression of brain activity related to a car-following task with an auditory task: An fMRI study

Driving a car in daily life involves multiple tasks. One important task for safe driving is car-following, the interference of which causes rear-end collisions: the most common type of car accident. Recent reports have described that car-following is hindered even by hands-free mobile telephones. We conducted functional MRI with 18 normal volunteers to investigate brain activity changes that occur during a car-following task with a concurrent auditory task. Participants performed three tasks: a driving task, an auditory task, and a dual task in an fMRI run. During the driving task, participants use a joystick to control their vehicle speed in a driving simulator to maintain a constant distance from a leading car, which moves at varying speed. Language trials and tone discrimination trials are presented during the auditory task. Car-following performance was worse during the dual task than during the single-driving task, showing positive correlation with brain activity in the bilateral lateral occipital complex and the right inferior parietal lobule. In the medial prefrontal cortex and left superior occipital gyrus, the brain activity of the dual task condition was less than that in the single-driving task condition. These results suggest that the decline of brain activity in these regions may induce car-following performance deterioration.