Decreasing driver speeding with feedback and a token economy

On-road research suggests that driver feedback combined with a token economy (a system of delayed reinforcement whereby tokens or points are distributed following a desired behaviour and are later exchanged for desired items) can reduce speeding, and that an incentive system without feedback may be sufficient to achieve this reduction. In two studies, we investigated the necessary and sufficient conditions required for this intervention to reduce speeding, and the efficacy of conducting such research using a driving simulator. Study 1 served to validate the simulator procedure. Participants completed a simulated drive while receiving feedback on their speed and a speed-based token economy. The intervention decreased their speeding compared with that of a control group. Study 2 investigated the amount of speed reduction that could be achieved with just one intervention component (i.e., feedback alone or a token economy alone) compared with feedback and a token economy combined or a control condition. Participants completed a 30-min simulated drive. Overall, drivers who received feedback combined with a token economy spent the least amount of time driving above the speed limit, had the slowest mean speed, and had the smallest standard deviation of speed. Drivers exposed to a token economy alone showed similar speed reductions. However, drivers exposed to feedback alone drove at speeds similar to control participants. Replicating these results under more realistic operating conditions could inform policy-makers and car manufacturers. Furthermore, the simulator proved a cost-effective and efficient means for examining the intervention.     

Increasing following headway with prompts, goal setting, and feedback in a driving simulator

We evaluated the effects of prompting, goal setting, and feedback on following headway of young drivers in a simulated driving environment and assessed whether changes produced in following headway were associated with reductions in hard braking when drivers were and were not using cell phones. Participants were 4 university students. During baseline, drivers spent half of the time talking on cell phones while driving. At the start of the intervention, drivers were prompted to increase following headway while on the cell phones and were provided a specific target for following headway. Drivers were given feedback on increasing following headway when on cell phones at the end of each session. The intervention package was associated with an increase in following headway and a decrease in hard braking when participants were on and off the cell phones. Cell phone use did not affect any of the measures.     

Affective reactivity to cry sounds predicts young women’s reactivity and behavior in a simulated caregiving task

Different populations of adults (experienced vs. inexperienced caregivers, men vs. women, abusive vs. nonabusive parents, etc.) have been reported to differ in their affective reactions to the sounds of infant crying. These differences are thought to impact caregiving behavior and, in some instances, to affect long-term outcomes for infants. There can be great intra-group variation, however, even when group differences are significant; modeling developmental process will require a finer grained approach. We have undertaken a pair of studies intended to validate the Negative Affect Scale (NA) from the PANAS as a measure of individuals’ affective reactivity to cry sounds. In Study 1, 306 young women who were not yet mothers listened either to infant crying or to birdsong. The results supported the NA as a measure of reactivity to crying. In Study 2, a new sample of 301 young women listened to crying in a screening task; a group of “high reactors” (n = 21) and a group of “low reactors” (n = 22) then participated in a simulated caregiving situation. Individuals’ affective reactivity to the caregiving simulation mirrored their affective reactivity in the screening task, and rates and overall organization of caregiving behavior differed between the groups. Changes in negative affect, then, appear to be both a result of infant crying and a determinant of some aspects of caregiving behavior. Further studies will extend these laboratory results to real infants and their caregivers, and further validate the NA as a measure of individual differences in reactivity to cry sounds.     

Driving errors,estimated performance and individual characteristics under simulated and real road traffic conditions – A validation study

BackgroundThe suitability of driving simulators for the prediction of driving behaviour in road traffic has been able to be confirmed in respect of individual assessment parameters. However, there is a need for overarching approaches that take into account the interaction between various influencing factors in order to establish proof of validity. The aim of this study was to explore the validity of our driving simulator in respect of its ability to predict driving behaviour based on participants‘ observed driving errors and driver’s individual characteristics.Method41 healthy participants were assessed both in a Smart-Realo-Simulator and on the road. By means of linear modelling, the correlation between observed driving errors was investigated. In addition, the influence of self-reported and externally assessed driving behaviour as well as individual parameters (education and training; driving history) were analysed.ResultsBy including these factors, 58% of the variance could be explained. For observed driving errors, a relative validity was established. For self-reported and externally assessed driving behaviour, an absolute to relative validity emerged. The amount of time spent in education and training proved to have a significant influence on driving performance in the simulator, but not on the road.DiscussionIn general, our results confirmed the validity of our driving simulator with regard to observed and self-reported driving behaviour. It emerged that education and training as potential indicators of cognitive resources played a differential role regarding the study conditions. Since real road driving is considerably automated in experienced drivers, this result suggests that simulation-related behavioural regulation is challenged by additional cognitive demands as opposed to behavioural regulation extending to real road driving. However, the source of these additional cognitive demands remains currently elusive and may form the subject of future research.     

Effect of time pressure on steering control of the drivers in a car-following situation

The current study focused on analyzing steering control of the drivers during a car-following situation under increasing time pressure conditions. A driving simulator experiment was conducted on ninety-two participants to assess steering performance measures. Five different steering control measures: Variability in Steering Angle (VSA), Steering Reversal Rate (SRR), Steering Speed (SS), Stability of Steering Control (SSC), and Maximum Steering Swerve (MSS) were examined under No Time Pressure (NTP), Low Time Pressure (LTP), and High Time Pressure (HTP) driving conditions. Repeated measures ANOVA (for continuous data) and Friedman’s test (count data) with post-hoc analysis and Generalized Estimating Equation (GEE) modeling technique were used to investigate the influence of time pressure and different predictor variables. The statistical analysis showed that time pressure driving conditions significantly affected steering control of the drivers. The pairwise comparison of time pressure conditions revealed that HTP significantly affected most of the steering control measures as compared to LTP. Further, a GEE model also exhibited similar results where steering control measures were substantially influenced by HTP as compared to LTP. Moreover, in addition to time pressure conditions, demographic characteristics showed significant influence on steering control measures. The GEE model results showed that female drivers performed 13% more steering corrections (5° SRR) which led to better SSC by 124.44% than male drivers. Additionally, it was discovered that young-aged and experienced drivers took extra steering efforts to control lateral position of the vehicle by increasing 53.50% SS and 1% SRR compared to middle-aged and inexperienced drivers. The findings from the current study revealed that drivers undergo fast and abrupt steering maneuvers under time pressure conditions. The research approach demonstrated in the current study can be beneficial to discriminate minimum requirement of steering efforts and set-up threshold values for various steering evasion techniques to control and maintain safe lateral position during car-following maneuvers.     

Can prosocial attitude reduce the risk behavior in simulated driving?

High traffic density may lead to more traffic accidents because of more frequent lane change and overtaking behaviors, but drivers with different characteristics may exhibit different driving behaviors. The present study explored the difference in driving behaviors between drivers with a high/low prosocial attitude under high/low traffic density. In this study, a 2 (high/low prosocial attitude) *2 (high/low traffic density) mixed design was used to investigate the interaction between prosocial attitude and traffic density on lane change and overtaking behavior. The implicit association test paradigm was used to measure prosocial attitude, and drivers were divided into two groups. Forty subjects were asked to complete simulated driving tasks under the two conditions of high and low traffic density, and driving behaviors were recorded by driving simulators. The results show that high traffic density leads to more lane change and overtaking behavior. Drivers with a high prosocial attitude have better driving performance under both high and low traffic density, but drivers with a low prosocial attitude maintain a smaller transverse distance from adjacent vehicles in high traffic density, which may increase risk. This study provides support for the selection, training and intervention of professional drivers.     

Can driving condition prompt systems improve passenger comfort of intelligent vehicles? A driving simulator study

The main trend in the development of intelligent vehicles has been on ensuring comfort, safety, efficiency, and environmental sustainability. However, current research focuses primarily on the safety and energy saving of intelligent vehicles, and a comfortable driving experience through a human–machine interaction system has not been sufficiently investigated. This study used a high-fidelity 6-degree-of-freedom driving simulator to evaluate the impact of an independently-designed vehicle driving condition prompt (DCP) systems on subjective passenger comfort and motion sickness. The experiment showed that when future driving information is obtained through the vehicle DCP systems, the passengers' subjective comfort is improved, motion sickness is alleviated, and the degree of passenger posture instability is reduced. These conclusions contribute toward improving the comfort of autonomous vehicles and providing a reference for the future design of human–machine interaction systems for intelligent vehicles.     

Effectiveness of risk awareness perception training in dynamic simulator scenarios involving salient distractors

The Risk Awareness Perception Training (RAPT) has been shown to improve latent hazard anticipation in young drivers. However, previous evaluation scenarios in a driving simulator often lacked either dynamic road environment features or control for such variations. The current study investigated whether the effectiveness of RAPT persists even in the presence of dynamic and salient distractors. Twenty RAPT-trained drivers and twenty-one Placebo-trained young drivers (aged 18–21) drove through eight simulated driving scenarios with latent hazards. A pedestrian avatar served as a distractor and was placed across from the latent hazard location. In half of the scenarios, the pedestrian remained static while in the other half the pedestrian started to move, without potential interference with the driver’s travelling path, as the drivers approached the latent hazard. Consistent with previous research, RAPT-trained drivers demonstrated better latent hazard anticipation performance than Placebo-trained drivers regardless of dynamic movement of the pedestrian avatar. Additionally, RAPT-trained drivers adopted wider scanning patterns and fixated more frequently on both the latent hazard and the pedestrian compared to Placebo-trained drivers. The results imply that RAPT may protect drivers from being distracted by dynamic stimuli and allow them to scan safety–critical areas containing latent hazards. Furthermore, RAPT may not only improve tactical hazard anticipation skills, but also modal hazard anticipation skills in young drivers.     

Driver's avoidance characteristics to hazardous situations: A driving simulator study

When analyzing the causes of an accident, it is critical to determine whether the driver could have prevented the accident. In previous studies on the reaction times of drivers, the definition and values of reaction times vary, so applying reaction time is difficult. In such analysis, the driver’s reaction time from perception is required to determine whether the driver could have prevented the accident, but past studies are difficult to utilize in accident analysis as reaction time measurements were taken after the occurrence of hazardous situations. In this study, 93 subjects from age groups ranging from 20 s to 40 s participated in an experiment inside a full-scale driving simulator, to determine reaction time values that can be practically applied to accident analysis. A total of 4 hazardous accident situations were reproduced, including driving over the centerline, pedestrian jaywalking, a vehicle cutting in, and intersection traffic signal violation. The Time-To-Collision (TTC) was 2.5 s and the driving speed was set to the common city road speed limits of 60 and 80 km/h. An eye tracker was used to determine the driver’s Saccade Latency (SL) during hazardous situations. Brake Reaction Time from Perception (BRT_P), Steer Reaction Time from Perception (SRT_P), and Driver Reaction Time from Perception (DRT_P) were derived, and the measurements were statistically analyzed to investigate differences by age group, gender, speed, and type of hazardous situation. Most participants were found to avoid collisions by braking first rather than steering for the presented hazardous situations, except for the cutting in situation. Also, to determine a reaction time that would cover most drivers, the 85th percentile of DRT_P was calculated. The 85th percentile of DRT_P was in the range of 0.550 – 0.800 s. Specifically for each hazardous situation, it was 0.650 s for driving over the centerline, 0.800 s for the pedestrian jaywalking, 0.660 s for cutting in, and 0.550 s for the intersection traffic signal violation. For all 4 hazardous situations combined, the 85th percentile of DRT_P was 0.646 s. The findings can be utilized to determine the driver’s likelihood of avoiding accidents when faced with similar hazardous situations.