Tibor Petzoldt

Can driver education be improved by computer based training of cognitive skills

Deficits in cognitive skills, such as hazard perception, appear to have a tremendous influence on accident involvement of younger drivers. However, conventional forms of driver training have largely failed to build skills that extend beyond the provision of a descriptive knowledge of how to drive. Computer based training (CBT) has the potential to provide new ways to deal with this problem. In this study, a CBT module was developed to complement existing driver training programs by addressing critical cognitive skills. The CBT made use of video sequences of potentially hazardous driving situations, including multiple-choice questions with adaptive feedback, to increase levels of elaboration and understanding. To test effects, a sample of learner drivers completed either CBT, paper based training with similar content, or no training at all. A simulator experiment confirmed that CBT participants exhibited earlier glances towards critical cues and relevant areas in the visual field than participants of the other two groups. It is concluded that CBT can potentially assist instruction of cognitive skills necessary for save driving.

Learning effects in the lane change task (LCT) – Realistic secondary tasks and transfer of learning

Driver distraction is a factor that is heavily involved in traffic crashes. With in-vehicle devices like navigation systems or mobile phones on the rise, the assessment of their potential to distract the driver has become a pressing issue. Several easy-to-use methods have been developed in recent years to allow for such an assessment in the early stages of product development. One of these methods is the lane change task (LCT), a simple driving simulation in which the driver has to change lanes as indicated by different signs along the road. Although the LCT is an ISO sanctioned procedure, there are still open questions. One issue are learning effects which have been found in previous studies and which have the potential to compromise the comparability of test results. In this paper, we present results on two experiments that further explored the effect of previous experience on LCT and secondary task performance. The results confirm that learning effects occur when combining the LCT with a realistic secondary task. Also, we found evidence for the transfer of learning from one secondary task to another to some degree, provided that the two tasks are sufficiently similar.

The Critical Tracking Task A Potentially Useful Method to Assess Driver Distraction

Objective: We report on four experiments that investigated the critical tracking task’s (CTT) potential as a tool to measure distraction. Background: Assessment of the potential of new in-vehicle information systems to be distracting has become an important issue. An easy-to-use method, which might be a candidate to assess this distraction, is the CTT. The CTT requires an operator to stabilize a bar, which is displayed on a computer screen, such that it does not depart from a predefined target position. As the CTT reflects various basic aspects of the operational level of the driving task, we used it as a simple surrogate for driving to assess the CTT’s capabilities. Method: We employed secondary tasks of varying demand, artificial tasks as well as tasks representative of secondary tasks while driving, and asked participants to perform them together with the CTT in parallel. CTT performance, secondary task performance, and subjective ratings of load were recorded and analyzed. Results: Overall, the CTT was able to differentiate between different levels of demand elicited by the secondary tasks. The results obtained corresponded with our a priori assumptions about the respective secondary tasks’ potential to distract. Conclusion: It appears that the CTT can be used to assess in-vehicle information systems with regard to their potential to distract drivers. Additional experiments are necessary to further clarify the relationship between driving and CTT performance. Application: The CTT can provide a cost-effective solution as part of a battery of tests for early testing of new in-vehicle devices.

Use of adaptive cruise control functions on motorways and urban roads: Changes over time in an on-road study

The study aimed at investigating how drivers use Adaptive Cruise Control and its functions in distinct road environments and to verify if changes occur over time. Fifteen participants were invited to drive a vehicle equipped with a Stop & Go Adaptive Cruise Control system on nine occasions. The course remained the same for each test run and included roads on urban and motorway environments. Results showed significant effect of experience for ACC usage percentage, and selection of the shortest time headway value in the urban road environment. This indicates that getting to know a system is not a homogenous process, as mastering the use of all the systems functions can take differing lengths of time in distinct road environments. Results can be used not only for the development of the new generation of systems that integrate ACC functionalities but also for determining the length of training required to operate an ACC system.

Risk compensation? – The relationship between helmet use and cycling speed under naturalistic conditions

INTRODUCTION An argument against mandatory helmet use is based on the idea of risk compensation, which means that cyclists might ride faster when wearing a helmet (Lardelli-Claret et al., 2003). However, questionnaire and experimental studies were unable to find evidence for this assumption (Fyhri et al., 2012; Fyhri & Philipps, 2013). Simultaneously, other factors with a potential role in helmet use and cycling speed, such as trip length and rider characteristics have been neglected in such considerations. The goal of the analysis presented in this paper was therefore to investigate the relationship between helmet use and cycling speed under naturalistic conditions while taking characteristics of cyclists and bicycles into account. METHOD As part of a naturalistic cycling study, we equipped the bicycles of conventional and e-bike riders with data acquisition systems to record speed and trip distance. It included two cameras (one for the face of the participant, another one for the forward scenery). For the analysis presented in this paper, we used the data of 76 participants (28 conventional bicycles, 48 e-bikes). RESULTS In total, participants used their helmet for 56% of all trips. Helmets were used more frequently for longer trips. A linear mixed model, in which trip length, helmet use, bicycle type, age, and gender were used as predictors showed that helmet use did not play a significant role for cycling speed. Instead, all other factors that were analyzed, with the exception of gender, had a significant relationship to cycling speed. DISCUSSION The assumption of risk compensation as a result of the use of a helmet could not be confirmed. Instead, the findings seem to support the suggestion that cyclists who undertake trips at potentially higher speed levels are aware of their increased risk, and actively try to reduce it through the use of a helmet.

Time to Arrival Estimates, (Pedestrian) Gap Acceptance and the Size Arrival Effect

Various studies have found that road users’ acceptance of gaps to cross in front of another vehicle is dependent on the approaching vehicle’s size, with smaller accepted gaps in front of smaller vehicles. At the same time, the so called size arrival effect is well known from research on time to collision / time to arrival estimates, where larger objects / vehicles tend to be judged as arriving earlier than smaller objects / vehicles. However, so far there has been no attempt to connect these two approaches in a single experiment to investigate whether the size arrival effect that is prevalent in time to arrival estimates can explain the variations in gap acceptance. In this experiment, twenty-seven participants observed video clips of approaching virtual vehicles of varying size (truck, bus, van, two different cars and a motorcycle) from a pedestrian’s perspective, and were either required to indicate a crossing decision, or to estimate time to arrival. While, overall, the effect of vehicle size was clearly visible for both crossing decision and time to arrival estimates, there was also a clear exception in form of the motorcycle, which went with larger accepted gaps than some of the larger vehicles. This exception might be explained by the participants’ subjective rating of perceived threat, which was rather high for the motorcycle. As (with the exception of the motorcycle), vehicle size and perceived threat correlated substantially, it is unclear at this stage to what degree these two factors contribute to perceived time to arrival and crossing decisions.