Browsing by Author "Ward, Nic"

Now showing 1 - 8 of 8
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    Developing Driving Support Systems to Mitigate Behavioral Risk Patterns Among Teen Drivers
    (University of Minnesota Center for Transportation Studies, 2007-08) Brovold, Shawn; Ward, Nic; Donath, Max; Simon, Stephen
    Based on statistics from the Centers for Disease Control and Prevention (2003), motor vehicle deaths are the leading cause of teenage fatalities. A possible approach to mitigate the incidence of teenage driver crashes and fatalities is through the use of in-vehicle technology. The design and development of a first-generation prototype Teen Driver Support System (TDSS) to explore the feasibility and opportunities of such technology has been completed. The TDSS system includes technology designed to address several primary contributing factors associated with the majority of teen fatal crashes: speeding, seatbelt use, driver inexperience, and alcohol use. This has been implemented using a combination of what researchers call forcing, feedback, and/or reporting functions. Forcing functions take the form of ignition interlocks to enforce seat belt compliance and sober driving. A feedback function provides real-time tutoring and warnings about illegal or unsafe speeds through auditory warnings. A reporting function records vehicle information for parents to review and supervise (and enforce) teen driver performance. A speed feedback and reporting component is used for driver compliance with safe travel speeds. The system correlates the location (using GPS) of the vehicle to a digital road map and the road's corresponding speed limit. A weather-based speed element incorporates current weather information that is used to warn a driver if the vehicle's speed is too high for current weather conditions. Similarly, speed warnings specific to curves are included to warn if speed is excessive for the prevailing geometry. With the prototype TDSS, the researchers developed a method of integrating a seat belt interlock that requires the driver's seat belt to be engaged before the vehicle will start. Seat belt use is continuously monitored during each trip, and lack of seat belt use is recorded for later review. An additional interlock for alcohol is reserved for teen drivers with preexisting alcohol-related convictions. Since alcohol interlock systems are commercially available, they can be demonstrated as an optional component of the TDSS. In anticipation of potential future applications, such as the enforcement of certain graduated driver licensing (GDL) requirements, the system includes a biometric fingerprint component, which uses a fingerprint sensor to identify the driver and parent so that the system can log the number of training hours spent behind the wheel.
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    Driving Performance During Cell Phone Conversations and Common In-Vehicle Tasks While Sober and Drunk
    (2005-10-01) Rakauskas, Mick; Ward, Nic
    The crash risk associated with cell phone use while driving is a contentious issue. Many states are introducing Advanced Traveler Information Systems (ATIS) that may be accessed with cell phones while driving (e.g. 511 Traveler Information Services). In these contexts, there is a need for relevant research to determine the risk of cell phone use. This study compared driver performance while conversing on a hands-free cell phone to conditions of operating common in-vehicle controls (e.g., radio, fan, air conditioning) and alcohol intoxication (BAC 0.08). In addition, the study examined the combined effects of being distracted and being intoxicated given that there may be a higher risk of a crash if the driver engages in a combination of risk factors. During simulated traffic scenarios, resource allocation was assessed through behavioral measures and an event-related potential (ERP) novelty oddball paradigm. The results indicated that during a car following scenario, drivers engaged in the conversations or completing in-vehicle tasks were more impaired than drivers that were not involved in any distraction task. Indeed, both the cell phone and in-vehicle sources of distraction were generally more impairing than intoxication at the legal limit. These results will be used in a follow up study in order to compare the effects on attention of driving and using 511 to distraction from these tested distractions.
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    Effects of Alcohol on Motorcycle Riding Skills
    (Minnesota Department of Transportation, 2007-12) Creaser, Janet; Ward, Nic; Rakauskas, Mick; Boer, E.; Shankwitz, Craig; Nardi, Flavia
    Alcohol is known to disrupt the effect of neurotransmitters and impair various psychomotor skills. Indeed, alcohol intoxication is a significant risk factor for fatal traffic crashes, especially when riding a motorcycle. At present, there is sparse research on the impairing effects of alcohol on skills involved in motorcycle control. This study was designed to measure the effect of alcohol (up to a blood alcohol concentration of .08 grams per deciliter) on a broad set of basic riding skills. These riding skills were assessed on a test track with task scenarios based on the Motorcycle Safety Foundation’s training program. This study used a balanced incomplete block design to remove confounding artifacts (learning effects) by randomizing four BACs across three test days. Performance was characterized in terms of riding strategy used to cope with the effects of alcohol as a neurological stressor and the amount of resulting impairment with reference to specified performance standards. The analysis controlled for rider gender and age, riding skill, and drinking history. The results showed there were observable changes in motorcycle control and rider behavior in response to alcohol that are indicative of impairment. In general, intoxicated riders demonstrated longer response times and adopted larger tolerances leading to more task performance errors. Riders appeared to protect bike stability at the expense of other task performance and riders tried harder -- where possible -- to fully or partially compensate for the negative effects of alcohol. Most of the alcohol effects were evident at the per se BAC .08 g/dL level, but some of the effects were observed at the lower BAC .05. Given that this study used experienced riders performing highly practiced tasks with low to moderate levels of alcohol, the effect of alcohol on motorcycle control and rider behavior were modest except when task demand was high (offset weave), time pressure was high (hazard avoidance for near obstacles), and tolerances were constrained (circuit track). The practical significance of the findings was discussed in terms of study constraints.
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    Generational Perspective on Teen and Older Drivers on Traffic Safety in Rural and Urban Communities
    (Minnesota Department of Transportation, 2008-09) Manser, Michael; Rakauskas, Michael; Ward, Nic; Jones, Pam; Mayer, Amy; Armson, Rossana
    The purpose of this project was to explore beliefs and attitudes about risky driving behavior and traffic safety interventions between urban and rural drivers as a function of age. This was accomplished by conducting focus groups and surveys in rural and urban areas with teens and seniors. Results indicated that traffic safety policy for teens should focus on distraction and sensory-motor functioning amongst seniors. In terms of traffic safety policy for rural areas, attention should be given to interventions promoting seatbelt compliance. Relative to traffic safety interventions, teens felt GDL helped them become better drivers but weren’t convinced GDL had made them better/safer. Teen felt smart technology could have positive effects on safety, but an acceptable program based on this technology needs to balance factors such as cost, robustness, and limitations on driving. Seniors were receptive to mandatory testing but felt it must be flexible, objectively administered, and based on criteria other than age. Rural seniors were concerned about alternative mobility programs for those drivers that fail the proposed test. Relative to these alternative programs, seniors’ acceptance was related to the perceived accessibility to a safe and affordable program that is sufficiently versatile to accommodate a range of transportation needs.
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    Intersection Decision Support: An Overview
    (Minnesota Department of Transportation, 2007-09) Donath, Max; Shankwitz, Craig; Ward, Nic; Creaser, Janet
    Minnesota joined with California, Virginia, and the FHWA in a pooled fund consortium (the Infrastructure Consortium) dedicated to improving intersection safety. The Minnesota team's objective is to develop effective strategies to mitigate high crash rates at rural intersections. Rural Intersection Decision Support (IDS) focuses on enhancing the driver's ability to successfully negotiate rural intersections. The system uses sensing and communication technology to identify safe gaps in traffic on a high-speed rural expressway and communicate this information to drivers waiting to enter the intersection from a minor intersecting road. The goal of this system is to improve safety without introducing traffic signals, which on high-speed rural roads often lead to an increase in rear-end crashes. The Rural IDS research program achieved four main research results: an analysis of rural expressway intersections, including development of a technique to identify those with higher-than-expected crash rates; development of a statistical model that can be used to estimate the benefits of deploying IDS at a specific rural intersection; design and implementation of a rural intersection surveillance and data acquisition system capable of quantifying the behavior of drivers; and a task analysis, design study, and simulator-based evaluation of Driver Infrastructure Interface (DII) concepts for communicating relevant information to stopped drivers. This report summarizes the results of the rural IDS system.
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    A Simulator-Based Evaluation of Smart Infrastructure Concepts for Intersection Decision Support for Rural Thru-STOP Intersections
    (Minnesota Department of Transportation, 2007-08) Creaser, Janet; Rakauskas, Mick; Ward, Nic; Laberge, Jason
    This report describes the human factors basis for an intersection decision support (IDS) system intended to improve the safety of rural intersections in Minnesota's Interregional Corridors (IRCs). The purpose of the human factors effort is to understand the task of rural intersection negotiation, identify high-risk user groups, describe the human factors that contribute to intersection accidents, and determine what conceptual types of information to present in the IDS display to improve driver performance and safety. Consistent with the original infrastructure consortium proposal, this report emphasizes gaps, older drivers, and rural thru-STOP intersections (Donath & Shankwitz, 2001). This is because older drivers have a high accident risk at rural thru-STOP intersections and problems with gap detection, perception, and acceptance are contributing factors. A task analysis of rural thru-STOP negotiation was used to define the informational requirements for an IDS system for assisting with gap detection, perception and judgment. An abstraction hierarchy defined the operator (driver) constraints relevant to an infrastructure-based IDS system. Four design concepts were constructed and tested in a driving simulator with older (55+) and younger (20-40) drivers in day and night driving conditions. Two designs resulted in the largest mean gap acceptance across groups when compared to baseline. The two design concepts also were most favored by the majority of participants.
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    System Performance and Human Factors Evaluation of the Driver Assistive System (DAS)
    (2003-12-01) Rakauskas, Mick; Ward, Nic; Shankwitz, Craig; Donath, Max
    This study aimed to determine the usefulness of the Driver Assistive System (DAS) in the context of plowing roads during low-visibility conditions. Driving performance, driver workload, and system performance were to be compared in a field operational test (FOT). Geographical location of the driver's route proved to play a large part in the desirability and perceived reliability of the system, as rural drivers preferred the system due to the lack of lighting and visual guidance while driving in low-visibility conditions. Most drivers did not have problems remembering how to use the DAS, and that the system made them feel safer and more in control while driving. The haptic seat was praised for giving warnings while letting them keep their eyes on the road or performing other in-cab tasks and their ideal configuration would be to use the haptic seat and/or the HUD. Due to an uncharacteristically mild winter weather conditions, it was decided that the FOT would not provide enough experience using the DAS during low-visibility conditions to make reasonable conclusions on driving performance. Therefore, it was necessary to use an additional experimental design with a track test, which is discussed in a supplemental document (Rakauskas et al., 2003).
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    System Performance and Human Factors Evaluation of the Driver Assistive System (DAS): Supplemental Track Test Evaluation
    (2003-11-01) Rakauskas, Mick; Ward, Nic; Shankwitz, Craig; Donath, Max
    This track test supplements an attempted field operational test (Rakauskas et al., 2003) which did not provide enough experience using the Driver Assistive System (DAS) during low-visibility conditions to make reasonable conclusions on driving performance. This study aimed to determine the usefulness of the DAS in the context of simulated low-visibility conditions. Drivers drove in clear, low-visibility, and DAS-assisted low-visibility conditions. Driving performance measures were taken while driving and drivers were asked workload, trust, and subjective response questions after each condition and post-experiment. The DAS enabled drivers to maintain consistent lane position and to make fewer steering corrections than while driving the low-visibility condition. Using the DAS during low-visibility conditions did not change speed performance and aided the driver by providing additional information about the road. More mental effort was reported while assisted by the DAS than while driving unassisted in the low-visibility condition. This was expected since drivers were presented with and were expected to mentally process more information while assisted. Many of the trends found were consistent with our previous thoughts on how the DAS would perform. However, due to the small number of drivers tested in the FOT and track testing studies there was low power for our statistical analyses. We encourage further research with the DAS on larger numbers of drivers or in a more powerful study design. Some changes are also recommended for future versions, such as providing a warning prior to loss of GPS fix. Project study to assess the usefulness of the Driver Assistive System (DAS) in the context of driving snowplows in low-visibility conditions on a test track. The system was found to be useful; several design improvements to the system are suggested to maximize its effectiveness.