| 1. |
- Dozza, Marco, 1978, et al.
(författare)
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Using naturalistic data to assess e-cyclist behavior
- 2016
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Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour. - : Elsevier BV. - 1369-8478. ; 41, s. 217-226
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Tidskriftsartikel (refereegranskat)abstract
- In Europe, the use of electric bicycles is rapidly increasing. This trend raises important safety concerns: Is their use compatible with existing infrastructure and regulations? Do they present novel safety issues? How do they impact other traffic? Monitoring e-cyclist behavior in real traffic would allow us to begin addressing these concerns. This study instrumented electric bicycles to monitor e-cyclists’ behavior in a naturalistic fashion. Data was collected from 12 bicyclists, each of whom rode an instrumented bicycle for two weeks. In total, 1500 km worth of data were collected, including 88 critical events (crashes and near-crashes). Analysis of these critical events identified pedestrians, light vehicles and other bicycles as main threats to a safe ride. Other factors also contributed to crash causation, such as being in proximity to a crossing or encountering a vehicle parked in the bicycle lane. A comparison between electric and traditional bicycles was enabled by the availability of data from a previous study a year earlier, which collected naturalistic cycling data from traditional bicycles using the same instrumentation as in this study. Electric bicycles were found to be ridden faster, on average, than traditional bicycles, in addition to interacting differently with other road users. The results presented in this study also suggest that countermeasures to bicycle crashes should be different for electric and traditional bicycles. Finally, increasing electric bicycle conspicuity appears to be the easiest, most obvious way to increase their safety.
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| 2. |
- Schindler, Ron, 1991, et al.
(författare)
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Making a few talk for the many – Modeling driver behavior using synthetic populations generated from experimental data
- 2021
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Ingår i: Accident Analysis and Prevention. - : Elsevier BV. - 0001-4575. ; 162
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Tidskriftsartikel (refereegranskat)abstract
- Understanding driver behavior is the basis for the development of many advanced driver assistance systems, and experimental studies are indispensable tools for constructing appropriate driver models. However, the high cost associated with testing is a serious obstacle in collecting large amounts of experimental data. This paper presents a methodology that can improve the reliability of results from experimental studies with a limited number of participants by creating a virtual population. Specifically, a methodology based on Bayesian inference has been developed, that generates synthetic cases that adhere to various real-world constraints and represent possible variations of the observed experimental data. The application of the framework is illustrated using data collected during a test-track experiment where truck drivers performed a right turn maneuver, with and without a cyclist crossing the intersection. The results show that, based on the speed profiles of the dataset and physical constraints, the methodology can produce synthetic speed profiles during braking that mimic the original curves but extend to other realistic braking patterns that were not directly observed. The models obtained from the proposed methodology have applications for the design of active safety systems and automated driving demonstrating thereby that the developed framework has great promise for the automotive industry.
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| 3. |
- Ana, Ferreira, et al.
(författare)
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Gender and age-related differences in the perception of in-vehicle mobile phone usage among Portuguese drivers
- 2012
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Ingår i: IET Intelligent Transport Systems. - 1751-9578 .- 1751-956X. ; 7:2, s. 223-229
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Tidskriftsartikel (refereegranskat)abstract
- It has already been proved that the use of the mobile phone while driving has a negative impact on the driving performance, increasing the risk of being involved in a car accident. However, in order to plan adequate corrective actions, there is the need to know more about people's usage of mobile phone while driving and what are drivers' opinions about the risk represented by that action. The aim of the present study was three-fold: to investigate the patterns of use of the mobile phone while driving by gender and age, to find out the prevalence of hands-free systems use by gender and age and, finally, to understand the perceived hazard in using the mobile phone while driving by gender and age. A sample of 769 Portuguese drivers answered a web-based survey developed in the frame of the European project INTERACTION. The answers revealed that the rate of mobile phone use among Portuguese drivers is very high. In addition, results showed that drivers perceived talking on a hands-free mobile phone while driving as much less dangerous compared with speaking on a hand-held mobile phone. Based on those results, further research is suggested.
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| 4. |
- Bianchi Piccinini, Giulio, 1982, et al.
(författare)
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Adaptive human machine interface based on the detection of driver's cognitive state using machine learning approach
- 2014
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Ingår i: Intelligenza Artificiale. - 2211-0097. ; 8:2/2014, s. 163-179
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Tidskriftsartikel (refereegranskat)abstract
- Cognitive distraction during the driving task might cause impairment of detection performance and of the recognition and/or response selection, increasing the risk of road crashes. In order to avoid or mitigate the negative effects related to cognitive distraction, this paper describes the development and testing of a Cooperative Lane Change Assistant (C-LCA) system: it takes into account the real-time driver's cognitive state by means of a cognitive distraction classifier expressly designed and it implements road cooperation between the vehicles thanks to a cooperative driver model. Three different test sessions were conducted on a static driving simulator and, in each test session, the participants carried out several analogous runs of a reference protocol test, derived from the Lane Change Task. Using the data collected during the first test session, the cognitive distraction classifier was developed using Machine Learning techniques. In the remaining two sessions, a specific C-LCA HMI prototype with visual and acoustic interfaces has been evaluated. The results show that the C-LCA reduced the workload during the lane change manoeuvres compared both with the baseline and with the assistance of a non-cooperative warning system. As well, the users expressed satisfaction about the Visual Interface and Acoustic Interface designed for the C-LCA.
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| 5. |
- Bianchi Piccinini, Giulio, 1982, et al.
(författare)
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Driver's behavioral adaptation to Adaptive Cruise Control (ACC): The case of speed and time headway
- 2014
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Ingår i: Journal of Safety Research. - : Elsevier BV. - 0022-4375. ; 49, s. 77-84
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Tidskriftsartikel (refereegranskat)abstract
- Problem: The Adaptive Cruise Control is an Advanced Driver Assistance System (ADAS) that allows maintaining given headway and speed, according to settings pre-defined by the users. Despite the potential benefits associated to the utilization of ACC, previous studies warned against negative behavioral adaptations that might occur while driving with the system activated. Unfortunately, up to now, there are no unanimous results about the effects induced by the usage of ACC on speed and time headway to the vehicle in front. Also, few studies were performed including actual users of ACC among the subjects. Objectives: This research aimed to investigate the effect of the experience gained with ACC on speed and time headway for a group of users of the system. In addition, it explored the impact of ACC usage on speed and time headway for ACC users and regular drivers. Method: A matched sample driving simulator study was planned as a two-way (2 x 2) repeated measures mixed design, with the experience with ACC as between-subjects factor and the driving condition (with ACC and manually) as within-subjects factor. Results: The results show that the usage of ACC brought a small but not significant reduction of speed and, especially, the maintenance of safer time headways, being the latter result greater for ACC users, probably as a consequence of their experience in using the system. Summary: The usage of ACC did not cause any negative behavioral adaptations to the system regarding speed and time headway. Practical applications: Based on this research work, the Adaptive Cruise Control showed the potential to improve road safety for what concerns the speed and the time headway maintained by the drivers. The speed of the surrounding traffic and the minimum time headway settable through the ACC seem to have an important effect on the road safety improvement achievable with the system. (C) 2014 National Safety Council and Elsevier Ltd. All rights reserved.
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| 6. |
- Bianchi Piccinini, Giulio, 1982, et al.
(författare)
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Effects on driving task and road safety impact induced by the usage of adaptive cruise control (ACC): a focus groups study
- 2012
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Ingår i: International Journal of Human Factors and Ergonomics. - 2045-7804 .- 2045-7812. ; 1:3, s. 234-253
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Tidskriftsartikel (refereegranskat)abstract
- Adaptive cruise control (ACC), through the partial automation of the longitudinal driving task, is expected to increase driving comfort and assure a positive impact on road safety. Previous research showed that some side effects can result from the usage of the ACC. Those studies were mainly performed with drivers who never used the ACC before taking part in the experiments. For this reason, little information is available about how the ACC actually affects the driving task of real users of the system. In order to investigate the topic, two focus groups sessions were performed in Portugal with 13 ACC drivers. The findings revealed users’ satisfaction regarding the comfort and safety provided by the system. On the other hand, some cases of behavioural adaptations to the system were reported. Further research on the problem domain is suggested.
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| 7. |
- Bianchi Piccinini, Giulio, 1982, et al.
(författare)
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Factors contributing to commercial vehicle rear-end conflicts in China: A study using on-board event data recorders
- 2017
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Ingår i: Journal of Safety Research. - : Elsevier BV. - 0022-4375. ; 62, s. 143-153
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: In the last 30 years, China has undergone a dramatic increase in vehicle ownership and a resulting escalation in the number of road crashes. Although crash figures are decreasing today, they remain high; it is therefore important to investigate crash causation mechanisms to further improve road safety in China. Method: To shed more light on the topic, naturalistic driving data was collected in Shanghai as part of the evaluation of a behavior-based safety service. The data collection included instrumenting 47 vehicles belonging to a commercial fleet with data acquisition systems. From the overall sample, 91 rear-end crash or near-crash (CNC) events, triggered by 24 drivers, were used in the analysis. The CNC were annotated by three researchers, through an expert assessment methodology based on videos and kinematic variables. Results: The results show that the main factor behind the rear-end CNC was the adoption of very small safety margins. In contrast to results from previous studies in the US, the following vehicles' drivers typically had their eyes on the road and reacted quickly in response to the evolving conflict in most events. When delayed reactions occurred, they were mainly due to driving-related visual scanning mismatches (e.g., mirror checks) rather than visual distraction. Finally, the study identified four main conflict scenarios that represent the typical development of rear-end conflicts in this data. Conclusions: The findings of this study have several practical applications, such as informing the specifications of in-vehicle safety measures and automated driving and providing input into the design of coaching/training procedures to improve the driving habits of drivers.
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| 8. |
- Bianchi Piccinini, Giulio, 1982, et al.
(författare)
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How Do Drivers Respond to Silent Automation Failures? Driving Simulator Study and Comparison of Computational Driver Braking Models
- 2020
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Ingår i: Human Factors. - Chalmers University of Technology, Gothenburg, Sweden.; Volvo Group Trucks Technology, Gothenburg, Sweden.; Virginia Tech Transportation Institute, Blacksburg, USA.; University of Leeds, UK.; VTI, Gothenburg, Sweden. : SAGE Publications. - 1547-8181 .- 0018-7208. ; 62:7, s. 1212-1229
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Tidskriftsartikel (refereegranskat)abstract
- Objective: This paper aims to describe and test novel computational driver models, predicting drivers’ brake reaction times (BRTs) to different levels of lead vehicle braking, during driving with cruise control (CC) and during silent failures of adaptive cruise control (ACC). Background: Validated computational models predicting BRTs to silent failures of automation are lacking but are important for assessing the safety benefits of automated driving. Method: Two alternative models of driver response to silent ACC failures are proposed: a looming prediction model, assuming that drivers embody a generative model of ACC, and a lower gain model, assuming that drivers’ arousal decreases due to monitoring of the automated system. Predictions of BRTs issued by the models were tested using a driving simulator study. Results: The driving simulator study confirmed the predictions of the models: (a) BRTs were significantly shorter with an increase in kinematic criticality, both during driving with CC and during driving with ACC; (b) BRTs were significantly delayed when driving with ACC compared with driving with CC. However, the predicted BRTs were longer than the ones observed, entailing a fitting of the models to the data from the study. Conclusion: Both the looming prediction model and the lower gain model predict well the BRTs for the ACC driving condition. However, the looming prediction model has the advantage of being able to predict average BRTs using the exact same parameters as the model fitted to the CC driving data. Application: Knowledge resulting from this research can be helpful for assessing the safety benefits of automated driving.
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| 9. |
- Bianchi Piccinini, Giulio, 1982, et al.
(författare)
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Influence of oncoming traffic on drivers’ decision to overtake cyclists
- 2017
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Ingår i: Proceedings of the 2017 Road Safety & Simulation International Conference.
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Konferensbidrag (refereegranskat)abstract
- Active transportation - such as cycling - can provide health benefits to the population. However, cycling safety remains a major threat to favour the use of bicycles and, for this reason, more efforts are needed to reduce the number of crashes involving cyclists. One scenario which deserves special attention is driver’s overtaking of cyclists since it has an increased likelihood to lead to severe injuries. The decision process for the overtaking manoeuvre is highly influenced by driver’s subjective feeling of risk and the presented driving simulator study aimed to understand how drivers overtake cyclists in the presence of oncoming traffic. Forty-two Japanese participants were recruited to drive on a 16 km long route and were requested to perform eight overtaking manoeuvres of cyclists, with the oncoming vehicle at different values of nominal time to collision in each overtaking manoeuvre. The results showed that the nominal time to collision against the oncoming vehicle had a significant effect on the overtaking strategy (accelerative vs. flying) and on the minimum safety margins towards the bicycle chosen by the overtaking driver. Besides, analysing the data by overtaking strategy, a decrease in minimum safety margins towards the bicycle was found for drivers who opted for a flying overtaking strategy: the drivers who completed the overtaking manoeuvre without letting pass the oncoming traffic reduced their lateral distance to the bicycle when the nominal time to collision decreased. Finally, the current research showed that minimum lateral safety margins were larger in accelerative manoeuvres compared to flying manoeuvres in the most critical overtaking manoeuvre. Overall, the research show that the comfort – and, possibly, the safety – of cyclists might be compromised in overtaking manoeuvres with oncoming traffic. Also, the study provides some implications for the design of active safety systems and automated driving.
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| 10. |
- Bianchi Piccinini, Giulio, 1982, et al.
(författare)
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Influence of oncoming traffic on drivers’ overtaking of cyclists
- 2018
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Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour. - : Elsevier BV. - 1369-8478. ; 59:Part A, s. 378-388
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Tidskriftsartikel (refereegranskat)abstract
- Active transportation - such as cycling - can provide health benefits to the population. However, cycling safety remains a major threat to favour the use of bicycles and, for this reason, more efforts are needed to reduce the number of crashes involving cyclists. One crash scenario which deserves special attention is driver’s overtaking of cyclists since it has an increased likelihood to lead to severe injuries. During the overtaking manoeuvre, the monitoring of subjective risk can influence the decision-making process and lead to different outcomes. In this context, the present driving simulator study aims to investigate how the time to collision between oncoming traffic and subject vehicle affected the overtaking strategy, and the minimum safety margins towards the overtaken cyclist. The results show that a decrease in time to collision against the oncoming vehicle significantly affects the drivers’ overtaking strategy (accelerative vs. flying), inducing more drivers to choose an accelerative overtaking manoeuvre. The decrease in time to collision also produces a decrease in minimum safety margins to the cyclists for drivers who opt for a flying overtaking strategy. Finally, the current research shows that the minimum lateral safety margins were smaller and the mean speed higher in flying manoeuvres compared to accelerative manoeuvres. Overall, the combination of lower safety margins and higher mean speeds in flying overtaking manoeuvres seems to pose a risk for cyclists’ safety. The findings of the study provide some implications for the design of automated driving.
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| 11. |
- Bianchi Piccinini, Giulio, 1982, et al.
(författare)
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Reaction to a critical situation during driving with Adaptive Cruise Control for users and non-users of the system
- 2015
-
Ingår i: Safety Science. - : Elsevier BV. - 0925-7535 .- 1879-1042. ; 72, s. 116-126
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Tidskriftsartikel (refereegranskat)abstract
- Adaptive Cruise Control (ACC) is a system that maintains driver-selected speed and headway to a preceding vehicle. The system presents some limitations that are, in part or totally, unknown to the users. Hence, many drivers exhibit a rudimentary mental model of the system and place excessive trust in the device. As a consequence, negative effects on road safety can easily occur. However, to date, many studies conducted on ACC have comprised participants who had never used ACC previously. Therefore, there is limited knowledge of how ACC affects the driving performance of experienced users of the system. To shed light on this point, twenty-six participants, divided into two groups (ACC users and non-users) drove twice in the simulated environment (once with the ACC and once manually). During both drives, the participants experienced a critical situation (stationary vehicle stopped in the cruising lane of the highway). The results show that negative behavioural adaptations to the ACC resulted from the usage of the system with regard to the critical situation: the risk of collision during the driving with ACC was increased compared with the manual driving for both groups of drivers. Besides, the research stresses the negative large correlation between the driver’s mental model of ACC operation in the critical situation and the safety margins maintained by the ACC users during the same situation. Finally, it was found that the drivers’ trust in the system does not have an influence on the drivers’ behaviour during the trial with the ACC.
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| 12. |
- Dozza, Marco, 1978, et al.
(författare)
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Do cyclists on e-bikes behave differently than cyclists on traditional bicycles?
- 2014
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Ingår i: Proceedings of the 3rd International Cycling Safety Conference, Nov 18-19, Göteborg, Sweden.
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Konferensbidrag (refereegranskat)abstract
- Cycling is a healthy, environmentally-friendly and enjoyable activity, which unfortunately also claims more than 2000 lives every year in Europe. Many municipalities across Europe are wag-ing successful campaigns to increase cycling and, as a consequence, reduce pollution and con-gestion. However, at least in the short term, a surge in cycling will also challenge existing infrastructure, regulations, and the interaction among different road users. Further, cycling nature is changing as new electrified bicycles (e-bikes), able to maintain a constant 25km/h speed independent of road gradient or wind, become more and more prevalent. The extent to which e-bikes and their increasing prevalence impact safety is currently unknown and very hard to simulate with statistical models. In 2012, the BikeSAFE project collected 1474 km of naturalistic cycling data from traditional bi-cycles. In 2013, the e-BikeSAFE project collected 1549 km of naturalistic data from e-bikes. All studies took place in Göteborg in the same period of the year, and as much as possible in-volved the same participants. While these naturalistic data sets are limited and possibly not representative of the cycling situation in all of Europe, they are also the most advanced data today available for comparing how traditional and electrical bicycles behave in traffic, thus of-fering a promising test bed for developing data analysis methodologies.Five random video clips were extracted for each participant from the data collected in BikeSAFE and e-BikeSAFE, forming an overall analysis database of 140, 30-s long, full HD, video clips. Video reduction identified which road users were involved in the interactions with the traditional and electric bikes. During the analysis, potential influencing factors (e.g. bicycle lane width, gradient, and curvature) were also taken into account. Information from reduction of e-bike and traditional-bike videos was compared by means of odds ratios and combined with subjective data from questionnaires to determine the extent to which safety concerns about e-bike are legitimate.Results show that e-bikes and traditional bicycles are ridden differently: cyclists riding e-bikes experience more intense and different interactions with other road users, and prefer different riding conditions, possibly because of their higher speed. Further, specific infrastructures (as crossings) and secondary tasks (as using a phone) may be particularly dangerous for e-bikers. The results presented in this paper provide new ideas for the design of safer bicycle lanes and more conspicuous e-bikes.
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| 13. |
- Dozza, Marco, 1978, et al.
(författare)
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How do drivers overtake cyclists?
- 2016
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Ingår i: Accident Analysis and Prevention. - : Elsevier BV. - 0001-4575. ; 88, s. 29-36
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Tidskriftsartikel (refereegranskat)abstract
- In Europe, the number of road crashes is steadily decreasing every year. However, the incidence of bicycle crashes is not declining as fast as that of car crashes. In Sweden, cyclists are the most frequently injured road users. Collisions between bicycles and motorized vehicles are of particular concern because the high speed and large mass of motorized vehicles creates a high risk of serious injury to cyclists. In Sweden’s urban areas, bicycle lanes keep bicycles separated from motorized vehicles, but on rural roads bicycle lanes are often absent, requiring drivers to interact with cyclists— usually by overtaking them. During this maneuver, the driver regulates speed and lateral position, negotiating with potential oncoming traffic to stay within their comfort zone while approaching and passing the cyclist.In this study an instrumented bicycle recorded 145 overtaking maneuvers performed by car and truck drivers on public rural roads in Sweden. The bicycle was equipped with a LIDAR and two cameras to assess how drivers approached and circumvented the bicycle. The collected data allowed us to identify four overtaking phases and quantify the corresponding driver comfort zones. The presence of an oncoming vehicle was the factor that most influenced the maneuver, whereas neither vehicle speed, lane width, shoulder width nor posted speed limit significantly affected the driver comfort zone or the overtaking dynamics.
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| 14. |
- Engström, Johan A Skifs, 1973, et al.
(författare)
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Great expectations: A predictive processing account of automobile driving
- 2018
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Ingår i: Theoretical Issues in Ergonomics Science. - 1464-536X .- 1463-922X. ; 19:2, s. 156-194
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Tidskriftsartikel (refereegranskat)abstract
- Predictive processing has been proposed as a unifying framework for understanding brain function, suggesting that cognition and behaviour can be fundamentally understood based on the single principle of prediction error minimisation. According to predictive processing, the brain is a statistical organ that continuously attempts get a grip on states in the world by predicting how these states cause sensory input and minimising the deviations between the predicted and actual input. While these ideas have had a strong influence in neuroscience and cognitive science, they have so far not been adopted in applied human factors research. The present paper represents a first attempt to do so, exploring how predictive processing concepts can be used to understand automobile driving. It is shown how a framework based on predictive processing may provide a novel perspective on a range of driving phenomena and offer a unifying framework for traditionally disparate human factors models.
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| 15. |
- Farah, Haneen, et al.
(författare)
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Drivers’ Decision Making of Overtaking Strategies of Cyclists on Rural Roads–A Driving Simulator Experiment
- 2019
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Cyclists’ involvement in road crashes has not been improving with the same magnitude as other modes of transport. Especially, the interactions between cyclists and motorized traffic can end up with the most severe types of crashes. To improve the safety of these interactions, a thorough understanding of road users’ decisions and behaviours is first needed. In this study, the authors focus on drivers’ overtaking manoeuvres of cyclists on rural roads. The main objective of this study is to develop a model that can predict drivers’ decisions whether to perform a flying or an accelerative overtaking manoeuvre when approaching a cyclist in the presence of oncoming traffic. A driving simulator study was designed to collect trajectory data of the overtaking vehicle, cyclist, and oncoming traffic. Drivers’ characteristics data was collected using surveys. In total, 37 drivers participated, each of them performing 7 overtaking manoeuvres. Out of 259 overtaking manoeuvres, 168 were flying and 91 were accelerative. Two binary logistic regression models were developed and estimated. In the two models, the time-to-collision and the driver’s speed significantly affect the decision on the overtaking manoeuvre type. In the first model, the correlations among the observations of the same driver were captured through the drivers’ characteristics. In the second model, these correlations were captured through a driver specific error term. The overall performance is 87.7% and 94.9% for the first and second models, respectively. In the paper the authors discuss the usability of each model for policy making, system design, and system evaluation.
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| 16. |
- Farah, Haneen, et al.
(författare)
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Modelling overtaking strategy and lateral distance in car-to-cyclist overtaking on rural roads: A driving simulator experiment
- 2019
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Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour. - : Elsevier BV. - 1369-8478. ; 63, s. 226-239
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Tidskriftsartikel (refereegranskat)abstract
- The involvement of cyclists in road crashes has not been decreasing with the same magnitude as the involvement of other road users. In particular, the interactions between cyclists and motorized traffic can lead to high-severity crashes. To improve the safety of these interactions, a thorough understanding of road user behaviour is first needed. In this study, we focused on drivers overtaking cyclists on rural roads. The two main objectives of this study were to develop models that predicted: (a) drivers’ decisions to perform either a flying or an accelerative overtaking manoeuvre in the presence of oncoming traffic, and (b) the lateral comfort distance that drivers maintain from cyclists during the overtaking. A driving simulator study was designed to assess driver decision-making during the overtaking. The 37 drivers who participated in the study each performed seven overtaking manoeuvres with oncoming traffic. Out of the 259 overtaking manoeuvres, 168 were flying and 91 were accelerative. Binary logistic-regression models with mixed effects predicted the type of overtaking strategy (flying or accelerative). Driving speeds were found to significantly affect the strategy. The overall performance of the models predicting the strategy was 85–90%. Models were also developed for predicting the lateral comfort distance. The results show that the lateral comfort distance is mostly affected by the longitudinal distance between the subject vehicle and the oncoming vehicle, the longitudinal distance between the subject vehicle and the cyclist, and the presence of an oncoming vehicle—as well as by the drivers’ characteristics (sensation seeking in flying overtaking manoeuvres and ordinary violations in accelerative manoeuvres). The root mean square error, which was used to assess the performance of the models, ranged from 0.56 to 0.62. In conclusion, the models predicting the overtaking strategy performed reasonably well, while the models predicting lateral distance did not provide accurate predictions. The models predicting overtaking strategy may support (1) the development and evaluation of active safety systems, (2) the design of automated driving, and (3) policy making.
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| 17. |
- Ito, Daisuke, et al.
(författare)
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Difference between car-to-cyclist crash and near crash in a perpendicular crash configuration based on driving recorder analysis
- 2018
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Ingår i: Accident Analysis and Prevention. - : Elsevier BV. - 0001-4575. ; 117, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Analyzing a crash using driving recorder data makes it possible to objectively examine factors contributing to the occurrence of the crash. In this study, car-to-cyclist crashes and near crashes recorded on cars equipped with advanced driving recorders were compared with each other in order to examine the factors that differentiate near crashes from crashes, as well as identify the causes of the crashes. Focusing on cases where the car and cyclist approached each other perpendicularly, the differences in the car’s and cyclist’s parameters such as velocity, distance and avoidance behavior were analyzed. The results show that car-to-cyclist crashes would not be avoidable when the car approaching the cyclist enters an area where the average deceleration required to stop the car is more than 0.45 G (4.4 m/s2). In order for this situation to occur, there are two types of cyclist crash scenarios. In the first scenario, the delay in the drivers’ reaction in activating the brakes is the main factor responsible for the crash. In this scenario, time-to-collision when the cyclist first appears in the video is more than 2.0 s. In the second scenario, the sudden appearance of a cyclist from behind an obstacle on the street is the factor responsible for the crash. In this case, the time-to-collision is less than 1.2 s, and the crash cannot be avoided even if the driver exhibited avoidance maneuvers.
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| 18. |
- Koji, Mizuno, et al.
(författare)
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Comparison of Real Accident and Near Miss Incident of Cyclist Collisions Based on Drive Recorder
- 2017
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Ingår i: Proceedings of the 2017 JSAE Annual Congress (Spring).
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Konferensbidrag (refereegranskat)abstract
- In order to examine factors that caused vehicle-cyclist collisions, vehicle-cyclist collisions at intersections that were recorded on a car driving recorder were compared to that of near-miss incidents. It was found that unless the cyclist took action to avoid the collision, collisions occur when the car needed a deceleration of 9.8m/s2 or more to avoid the collision. Two different types of collisions were observed: delays of drivers to start braking after a cyclist is present, and the sudden appearance of the cyclist. The percentage of incidents where the cyclist suddenly appeared was higher in collisions cases compared to near-miss incidents.
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| 19. |
- Lin, Che-Tsung, 1979, et al.
(författare)
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Data Augmentation via Neural-Style-Transfer for Driver Distraction Recognition
- 2022
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Ingår i: The 8th International Conference on Driver Distraction and Inattention.
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Konferensbidrag (refereegranskat)abstract
- According to the National Highway Traffic Safety Administration, 3142 people were killed in motor vehicle crashes involving distracted drivers in 2019. Naturalistic driving datasets (NDD) have been widely used to study distracting activities while driving, with the aim of improving road safety. However, the time required to annotate videos to identify distracting activities is a major issue for research using NDD. Although full automation of the annotation process is not possible, the use of image classifiers is a way forward to hasten the classification of distractions and therefore the analysis of NDD. This paper presents the results obtained by applying image classifier to the publicly available Distracted Driver Dataset (DDD) and a sample of frames extracted from the EuroFOT and DriveC2X dataset. The results show that using ResNet-50 pretrained on Imagenet and Stylized Imagenet produces the highest accuracy on both DDD and our EuroFOT and DriveC2X datasets. The accuracy of the image classifier will now be tested on a different sample of the Swedish EuroFOT dataset, before using the image classifier for detecting distracting activities in other NDD. The faster identification of distracting activities will considerably hasten the future analyses of NDD.
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| 20. |
- Mohammadi, Ali, 1991, et al.
(författare)
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How do cyclists interact with motorized vehicles at unsignalized intersections? Modeling cyclists’ yielding behavior using naturalistic data
- 2023
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Ingår i: Accident Analysis and Prevention. - 0001-4575. ; 190
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Tidskriftsartikel (refereegranskat)abstract
- When a cyclist's path intersects with that of a motorized vehicle at an unsignalized intersection, serious conflicts may happen. In recent years, the number of cyclist fatalities in this conflict scenario has held steady, while the number in many other traffic scenarios has been decreasing. There is, therefore, a need to further study this conflict scenario in order to make it safer. With the advent of automated vehicles, threat assessment algorithms able to predict cyclists’ (other road users’) behavior will be increasingly important to ensure safety. To date, the handful of studies that have modeled the vehicle-cyclist interaction at unsignalized intersections have used kinematics (speed and location) alone without using cyclists’ behavioral cues, such as pedaling or gesturing. As a result, we do not know whether non-verbal communication (e.g., from behavioral cues) could improve model predictions. In this paper, we propose a quantitative model based on naturalistic data, which uses additional non-verbal information to predict cyclists’ crossing intentions at unsignalized intersections. Interaction events were extracted from a trajectory dataset and enriched by adding cyclists’ behavioral cues obtained from sensors. Both kinematics and cyclists’ behavioral cues (e.g., pedaling and head movement), were found to be statistically significant for predicting the cyclist's yielding behavior. This research shows that adding information about the cyclists’ behavioral cues to the threat assessment algorithms of active safety systems and automated vehicles will improve safety. Marie Skłodowska-Curie Actions; Innovative Training Network (ITN); Project name: SHAPE-IT;Grant number: 860410;Publication date: [2023]; DOI: [10.1016/j.aap.2023.107156]
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| 22. |
- Mohammadi, Ali, 1991, et al.
(författare)
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Understanding the interaction between cyclists and motorized vehicles at unsignalized intersections: Results from a cycling simulator study
- 2024
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Ingår i: Journal of Safety Research. - 0022-4375.
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Tidskriftsartikel (refereegranskat)abstract
- cyclists’ behavior to develop behavioral models that can predict the cyclist’s intent. Most conflicts between cyclists and vehicles happen at crossings where the road users share the path, especially at unsignalized intersections. However, few studies have investigated and modeled the interaction between cyclists and vehicles at unsignalized intersections. Method: A bike simulator experiment was conducted to scrutinize cyclists’ response process as they interacted with a passenger car at an unsignalized intersection. An existing unsignalized intersection in Gothenburg was simulated for test participants. Two independent variables were varied across trials: the difference in time to arrival at the intersection (DTA) and intersection visibility (IV). Subjective and quantitative data were analyzed to model the cyclists’ behavior. Results: When approaching the intersection, cyclists showed a clear sequence of actions (pedaling, braking, and head turning). The distance from the intersection at which cyclists started braking was significantly affected by the two independent variables. It was also found that DTA, looking duration, and pedaling behavior significantly affected cyclists’ decisions to yield. Finally, the questionnaire outputs show that participants missed eye contact or communication with the motorized vehicle. Conclusions: The kinematic interaction between cyclists and vehicles, along with the cyclist’s response process (visual and kinematic), can be utilized to predict cyclists’ yielding decision at intersections. From the infrastructural perspective, enhancing visibility at intersections has the potential to reduce the severity of interactions between cyclists and vehicles. The analysis of the questionnaire emphasizes the significance of visual communication between cyclists and drivers to support the cyclist’s decision-making process when yielding. Practical applications: The models can be used in threat assessment algorithms so that active safety systems and automated vehicles can react safely to the presence of cyclists in conflict scenarios. Marie Skłodowska-Curie Actions; Innovative Training Network (ITN); Project name: SHAPE-IT;Grant number: 860410;Publication date: [2024]; DOI: [10.1016/j.jsr.2024.05.007]
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| 23. |
- Pipkorn, Linda, 1991, et al.
(författare)
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The role of off-path glances: A quantitative analysis of rear-end conflicts involving Chinese professional truck drivers as the striking partners
- 2020
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Ingår i: Journal of Safety Research. - : Elsevier BV. - 0022-4375. ; 72, s. 259-266
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Tidskriftsartikel (refereegranskat)abstract
- © 2020 National Safety Council and Elsevier Ltd Introduction: Rear-end crashes are one of the most frequent crash types in China, leading to significant economic and societal losses. The development of active safety systems – such as Automatic Emergency Braking System (AEBS) – could avoid or mitigate the consequences of these crashes in Chinese traffic situations. However, a clear understanding of the crash causation mechanisms is necessary for the design of these systems. Method: Manually coded variables were extracted from a naturalistic driving study conducted with commercial vehicles in Shanghai. Quantitative analyses of rear-end crashes and near crashes (CNC) were conducted to assess the prevalence, duration, and location of drivers’ off-path glances, the influence of lead vehicle brake lights on drivers’ last off-path glance, and driver brake onset, and the influence of off-path glances and kinematic criticality on drivers’ response to conflicts. Results: The results indicate that the Chinese truck drivers in our study rarely engage in distracting activities involving a phone or other handheld objects while driving. Instead, they direct their off-path glances mainly toward the mirrors, and the duration of off-path glances leading to critical situations are shorter compared to earlier analyses performed in Western countries. The drivers also often keep small margins. Conclusions: Overall, the combination of short time headway with off-path glances directed toward the mirror originates visual mismatches which, associated to a rapid change in the kinematic situation, cause the occurrence of rear-end CNC. When drivers look back toward the road after an off-path glance, a fast response seems to be triggered by lower values of looming compared to previous studies, possibly because of the short time headways. Practical Application: The results have practical implications for the development of driver models, for the design of active safety systems and automated driving, and for the design of campaigns promoting safe driving.
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| 24. |
- Sagberg, Fridulv, et al.
(författare)
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A Review of Research on Driving Styles and Road Safety
- 2015
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Ingår i: Human Factors. - : SAGE Publications. - 1547-8181 .- 0018-7208. ; 57:No. 7, November 2015, s. 1248- 1275
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Forskningsöversikt (refereegranskat)abstract
- Objective: To outline a conceptual framework for understanding driving style and, based on this, review the state-of-the-art research on driving styles in relation to road safety.Background: Previous research has indicated a relationship between the driving styles adopted by drivers and their crash involvement. However, a comprehensive literature review of driving style research is lacking. Method: A systematic literature search was conducted, including empirical, theoretical and methodological research on driving styles related to road safety. Results: A conceptual framework was proposed where driving styles are viewed in terms of driving habits established as a result of individual dispositions as well as social norms and cultural values. Moreover, a general scheme for categorising and operationalizing driving styles was suggested. On this basis, existing literature on driving styles and indicators was reviewed. Links between driving styles and road safety were identified and individual and socio-cultural factors influencing driving style were reviewed. Conclusion: Existing studies have addressed a wide variety of driving styles, and there is an acute need for a unifying conceptual framework in order to synthesise these results and make useful generalisations. There is a considerable potential for increasing road safety by means of behaviour modification. Naturalistic driving observations represent particularly promising approaches to future research on driving styles. Application: Knowledge about driving styles can be applied in programmes for modifying driver behaviour and in the context of usage-based insurance. It may also be used as a means for driver identification and for the development of driver assistance systems.
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| 25. |
- Schindler, Ron, 1991, et al.
(författare)
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Truck drivers’ behavior in encounters with vulnerable road users at intersections: Results from a test-track experiment
- 2021
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Ingår i: Accident Analysis and Prevention. - : Elsevier BV. - 0001-4575. ; 159
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Tidskriftsartikel (refereegranskat)abstract
- Crashes involving cyclists and pedestrians in Europe cause the deaths of about 7600 persons every year. Both cyclists and pedestrians are especially exposed in crashes with motorized vehicles and collisions with trucks can lead to severe injury outcomes. The two most frequent crash scenarios between trucks and these vulnerable road users (VRU) are: a) when the truck wants to turn right at an intersection, with a cyclist riding parallel and planning to cross the intersection and b) when a pedestrian crosses in front of the truck in perpendicular direction to the movement of the truck. Advanced Driver Assistance Systems (ADAS)—that are expected to prevent or mitigate these crashes—benefit from detailed information about the behavior of truck drivers. This study is a first exploration of this research area, with the aim to assess how drivers negotiate the encounters with VRUs in the two scenarios described above. Thirteen participants drove an instrumented truck on a test-track. After some baseline recordings, the drivers experienced two laps where they encountered a cyclist target and a pedestrian target crossing their path. The results show that the truck drivers adapted their kinematic and visual behavior in the laps where the VRU targets were crossing the intersection, compared to the baseline laps. The speed profiles of the drivers diverged approximately 30 m from the intersection and glances were directed more often towards front right and right, during the scenario with the cyclist in comparison to baseline laps. For the scenario with the pedestrian crossing, the drivers changed their speed about 14 m from the intersection and glances were directed more often towards the front center, compared to baseline laps. As a result, both the speed and distance from the intersection at the end of the maneuver were significantly different between VRU and baseline laps. Overall, the findings provide valuable information for the design of ADAS that warn the drivers about the presence of a cyclist travelling in parallel direction or that intervene to avoid a collision with a cyclist or pedestrian.
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