Pedestrians’ road crossing behaviour in front of automated vehicles: Results from a pedestrian simulation experiment using agent-based modelling

The objective of this research is to explore the relation between personal characteristics of pedestrians and their crossing behaviour in front of an automated vehicle (AV). For this purpose, a simulation experiment was developed using Agent-Based Modelling (ABM) techniques. Sixty participants were asked to cross the road in a virtual environment displayed on a computer screen, allowing to record their crossing behaviour when in the presence of AVs and conventional vehicles (CVs). In some experimental configurations, the AVs communicated their intention to continue or not to continue their trajectories through the use of lights. The ABM allowed controlling the behaviour of the vehicles when interacting with the simulated avatar of the respondents. The subjects of the experiment were also asked to fill in a questionnaire about usual behaviour in traffic, as well as attitudes and risk perceptions toward crossing roads. The questionnaire data were used to estimate individual specific behavioural latent variables by means of principal component analysis which resulted in three main factors named: violations, lapses, and trust in AVs. The results of generalized linear mixed models applied to the data showed that besides the distance from the approaching vehicle and existence of a zebra crossing, pedestrians’ crossing decisions are significantly affected by the participants’ age, familiarity with AVs, the communication between the AV and the pedestrian, and whether the approaching vehicle is an AV. Moreover, the introduction of the latent factors as explanatory variables into the regression models indicated that individual specific characteristics like willingness to take risks and violate traffic rules, and trust in AVs can have additional explanatory power in the crossing decisions.     

Chimpanzees help others with what they want; children help them with what they need

Humans, including young children, are strongly motivated to help others, even paying a cost to do so. Humans’ nearest primate relatives, great apes, are likewise motivated to help others, raising the question of whether the motivations of humans and apes are the same. Here we compared the underlying motivation to help in human children and chimpanzees. Both species understood the situation and helped a conspecific in a straightforward situation. However, when helpers knew that what the other was requesting would not actually help her, only children gave her what she needed instead of giving her what she requested. These results suggest that both chimpanzees and human children help others but the underlying motivation for why they help differs. In comparison to chimpanzees, young children help in a paternalistic manner. The evolutionary hypothesis is that uniquely human socio‐ecologies based on interdependent cooperation gave rise to uniquely human prosocial motivations to help others paternalistically.     

Public perception of autonomous vehicles: A qualitative study based on interviews after riding an autonomous shuttle

Autonomous vehicles (AVs) can potentially compensate for human error whilst driving. Thus, the number of accidents and the amount of congestion, emissions and fuel consumption could be reduced. For such reduction to occur, insights into public acceptance of AVs must be considered because they are a crucial factor for the successful implementation of AVs in existing traffic systems.PurposeThis study aims to explore (1) the mobility behaviour of current passengers, (2) the perception of the public of how AVs can be applied, (3) the perceived challenges of AVs in terms of integration into existing traffic systems, (4) the general attitude of the public towards AVs and (5) the perceived safety of passengers after riding an autonomous shuttle with a maximum SAE level of 3 in the setting of mixed traffic.MethodThis qualitative study was conducted in Carinthia (Austria) in September 2018. Interviews were conducted with 19 participants aged between 20 and 75 years. The participants were recruited through purposeful sampling, and data were collected through in-depth, semistructured interviews which were recorded, transcribed, organised and analysed using systematic, qualitative content analysis.ResultsResults show that transport mobility plays an important role in social life. In rural areas, AVs can shift transportation modes from private cars to public transportation. The respondents perceive AVs as an alternative more than as a substitute for existing means of transportation. With the integration of AVs into existing traffic systems, the transportation of goods and people could be improved despite related uncertainties. This study explores different aspects of societal, technical, legal and economic challenges. Overall, the respondents feel positive about AVs. Responses regarding safety show that experience with AVs and speed are key factors.Originality/ValueThis study is one of the first to explain qualitatively public perceptions of AVs after an actual ride in an AV under real-life conditions. The results, which help understand AVs from the public’s perspective, may also provide guidelines for the successful integration of AVs in Austria.     

Factors explaining driver yielding behaviour towards pedestrians at courtesy crossings

Courtesy crossings are pedestrian crossing facilities where drivers are not legally required to stop for pedestrians, but are encouraged to do so by design elements such as stripes, coloured or textured road surfaces, visual narrowings of the carriageway, and ramps. There is little empirical evidence on drivers' behaviour or guidance on how to design these crossings. This paper analysed data for 937 interactions between drivers and pedestrians at 20 crossings across England, comparing driver yielding behaviour at courtesy crossings and at zebras (marked unsignalised crossings, where drivers are legally required to stop); and identifying the design elements associated with yielding behaviour at courtesy crossings. The analysis controlled for crossing stage; characteristics and situation of pedestrians and vehicles; characteristics of the road and site; and time context. Driver yielding behaviour was analysed for each separate traffic lane that pedestrians need to cross. We found that all four design elements considered (stripes, coloured/textured surface, visual narrowing, and ramps) increased the propensity of the first vehicle to stop and of any vehicle to stop. A before-after analysis then showed that adding a new element (stripes) to a courtesy crossing led to an increase in yielding rates from 20% to 97%. Overall, we found evidence supporting the use of multiple design elements in courtesy crossings. We discuss the implications of these findings for transport policy and urban design.     

Improving payment of traffic fines with financial incentives: Discounts vs. penalties

The effective enforcement of traffic laws is critical for improved road safety outcomes. Decisions to follow traffic rules and pay fines are influenced by formal institutions (e.g. laws, court summons, and fines) as well as informal institutions (e.g. norms and aspects of culture). Formal and informal institutions create incentives that should be designed to steer individuals’ behaviour towards desired outcomes. Unfortunately, there is no reason to believe that the institutions to deal with traffic violations in South Africa currently create effective incentives. This paper discusses the findings of a controlled laboratory experiment, conducted with a sample of university students, that tested the efficacy of different financial incentives that may influence the payment of traffic fines. An early payment discount was compared to a late payment penalty (used in other countries, for example, some states in the USA), and to the absence of any incentives. Furthermore, we examined whether the willingness to settle fines is sensitive to the likelihood of detection by the authorities. We found that introducing financial incentives significantly increases voluntary payment of fines, irrespective of whether immediate payment is encouraged with a discount or late payment is discouraged with a surcharge. In addition, subjects are more sensitive to the likelihood of detection when financial incentives are present.     

The impact of auditory continual feedback on take-overs in Level 3 automated vehicles

ObjectiveTo implement auditory continual feedback into the interface design of a Level 3 automated vehicle and to test whether gaze behavior and reaction times of drivers improved in take-over situations.BackgroundWhen required to assume manual control in take-over situations, drivers of Level 3 automated vehicles are less likely than conventional drivers to spot potential hazards, and their reaction time is longer. Therefore, it is crucial that the interface of Level 3 automated vehicles will be designed to improve drivers’ performance in take-over situations.MethodIn two experiments, participants drove a simulated route in a Level 3 automated vehicle for 35 min with one imminent take-over event. Participants’ gaze behavior and performance in an imminent take-over event were monitored under one of three auditory interface designs: (1) Continual feedback. A system that provides verbal driving-related feedback; (2) Persistent feedback. A system that provides verbal driving-related feedback and a persistent beep; and (3) Chatter feedback. A system that provides verbal non-driving-related feedback. Also, there was a control group without feedback.ResultsUnder all three auditory feedback designs, the number of drivers' on-road glances increased compared to no feedback, but none of the designs shortened reaction time to the imminent event.ConclusionIncreasing the number of on-road glances during automated driving does not necessarily improve drivers’ attention to the road and their reaction times during take-overs.ApplicationPossible implications for the effectiveness of auditory continual feedback should be considered when designing interfaces for Level 3 automated vehicles.     

Proposal of a driver profile classification in relation to risk level in overtaking maneuvers

Traffic crashes are a worldwide problem, and records have indicated frontal collisions have resulted in the most significant number of fatalities. Such a type of crash is frequently caused by improper overtaking of vehicles, which highlights the interference of human factors. Therefore, investigations on driver's risk perception are necessary. This study proposes a classification of driver's risk level through a decision tree using the Classification and Regression Tree (CART) algorithm from data collected from the overtaking maneuvers in a driving simulator. The model obtained by CART algorithm indicated young male drivers are more likely to take risks in overtaking maneuvers. The results were correlated with governmental records and similar studies. In addition, the results showed the potential of the tool for used as a risk level classifier, as well as the validation of the driving simulator in studies associated with human factor behaviours, accident analysis and investigation.     

An investigation of expertise in cycling: Eye tracking,Think Aloud and the influence of a competitor

ObjectivesTwo studies investigated expert-novice differences in information-seeking behaviour, cognitions and performance during cycling time trials (TT). Study 1 examined trained and novice cyclist’s cognitions whilst performing a TT, using a Think Aloud (TA) protocol and eye-tracking techniques. Study 2 investigated expertise differences during alone and competitive TTs.Methodsin Study 1, six trained and seven novice cyclists performed a 16.1 km TT. In Study 2, eight trained and ten novice cyclists performed three 16.1 km TT; a baseline TT, an alone TT and a trial against a virtual competitor. In both studies, participants were asked to TA and in Study 1 they also wore mobile gaze-tracking glasses. Performance feedback and a simulated TT course were visually displayed during all trials, as was a virtual avatar during the competitor trial. Verbalisations were coded into primary and secondary themes. Cognitions and pacing strategies were compared between groups and across the duration of the TTs. In Study 1, eye-tracking data for total dwell time and gaze frequency were calculated for each area of interest (Time Elapsed, Power, Heart Rate, Cadence, Distance Covered, Speed and Course Scenery).ResultsIn Study 1, no significant differences were found in information-seeking behaviour between groups, however there were expertise differences in the cognitive strategies used. Trained cyclists’ verbalisations were more performance-relevant (i.e., power output), whereas the untrained group were more focused on task completion (i.e., distance and time) and irrelevant information. Both groups talked more about distance and motivational thoughts in the later stages of the trial, and dwell time on distance feedback also increased in this final 4 km. In Study 2, the trained group performed faster than the untrained group but there were no significant differences in pace or performance between alone and competitive TTs for either group. Differences in cognitions were found between groups and across the TT duration.ConclusionBoth studies demonstrate that cognitive processes differ as a function of expertise during self-paced cycling time trials. There were no differences in information-seeking behaviour between trained and untrained cyclists and there was no effect of an opponent on pace or performance.