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With interest in collision avoidance technology for highway vehicles on the rise, this report presents an overview of current collision avoidance technology, the technical work required to bring these systems to a commercially viable product, and the societal issues that need addressing before wide-scale deployment can occur. Many questions remain about the benefits of deploying such systems, the costs, the effect of these systems on drivers, and the steps necessary to effectively regulate vehicles equipped with such systems. In addition to technical aspects, the report also discusses the issues that society will face during development and deployment of these systems, which may prove bigger impediments to deployment than technical issues. The report also recommends a research plan to perform fair, unbiased evaluations of emerging collision avoidance technology.

This project involved investigating the effect, if any, of rumble strips on stopping behavior at simulated rural-controlled intersections. Researchers used the wrap-around driver simulator at the University of Minnesota's Human Factors Research Laboratory for the project. Researchers varied the rumble strip type and the number of rumble strips and tested them on two different types of controlled intersections, two-way or four-way, and in the presence and absence of traffic. Results indicate that none of these manipulations seem to affect the point at which drivers stop at the controlled intersections or the point at which drivers start to slow down at controlled intersections. The research did reveal drivers brake more, earlier, when rumble strips are installed than they do if there are no rumble strips. Although they started to slow down at the same time and finished braking at the same time, there was more use of the brake earlier in the slowing down maneuver in the presence of rumble strips. Results also reveal that drivers brake more and earlier with full coverage rumble strips than they do with wheel track rumble strips.

This study analyzed the relationship between the size of the forward looking blindspot (FLB) produced by vehicles A-post (windshield frame), the speeds of two vehicles approaching an intersection at right angles, and driver behavior relative to a likely accident event. Researchers observed 28 volunteer participants directly and by four channels of on-board video cameras while they drove in a simulator at the Human Factors Research Laboratory. They noted the way that participants scanned the virtual environment and scored at four levels of scanning activity. They also tracked visual acquisition of the target vehicle and incidence of collision. Only 6.3% of the total fell into type one scanning (eyes fixed). Type II (eyes only) accounted for the highest incident rate at almost 44%. The study considered both as "inactive" forms of scanning. Target vehicle acquisition rate increased with the activity level of the scanning type. The target acquisition rate increased significantly from scanning level one to level two and from scanning level two to level three. There was not a significant increase in the acquisition rate from scanning level three to level four. Not surprisingly, collision rates decreased with increases in scanning level. Collision rates significantly dropped between scanning levels two and three and scanning levels three and four. Yield signs at intersections produced no significant correlation with acquisition rate, collision rate, or scanning level.

This research explores the potential safety effects of dynamic signing at rural horizontal curves. It accomplishes this by asking two key questions. First, is there a relationship between a vehicle's speed on the approach to a curve and the ability to successfully navigate the curve? Second, is there a difference between static and dynamic signing in the ability to reduce the speed of high-speed vehicles? Researchers assembled an off-the-shelf hardware and software package and deployed it at a four-degree curve along CSAH 54 in rural Dakota County. If purchased new, the package would cost about $50,000; however, an agency could deploy the components necessary to perform dynamic curve warning (a changeable message sign and radar unit) for approximately $10,000. The field test collected vehicle speed data for about 2,600 vehicles. In addition, researchers tracked and videotaped 600 vehicles. The data suggest, and statistical tests confirm, that the initial speed of a vehicle before entering a curve does have a statistically significant effect on the probability of successfully navigating through the curve. The data also indicated that the overall effect of the dynamic curve warning system on vehicle speeds is relatively small. However, the dynamic system had a much greater effect on high-speed vehicles than the static curve warning sign and the dynamic system significantly improved the ability of the high-speed vehicles to successfully navigate through the curve.

A driving simulation experiment was conducted to research interventions to right-angle crashes at rural Thru-STOP intersections, which accounted for 71% of Minnesota fatal crashes in 1998, 1999, and the first half of 2000. The interventions caused drivers to reduce speed as they neared the intersection, and implies that 1) drivers are less likely to inadvertently run stop signs when slowing down further from the intersection, 2) making the intersection more noticeable improves driver safety judgment, and 3) speed reductions on the major road of an intersection produce greater reductions in stopping distances.

This study presents statistically reliable conclusions based on a comparison of the operational and safety characteristics of rural intersections without turning lanes, with bypass lanes, and with left turn lanes. The basic work tasks associated with the research study included: a literature search of nationally published research reports, a survey of bypass lane use, a summary of the legal issues associated with passing on the right, operations and safety analyses, and a review of Minnesota Department of Transportation (Mn/DOT) recommended design guidelines and design features. The results of the safety and operations analyses did not offer a high degree of statistical reliability. However, a comparative crash analysis and a before-versus-after analysis suggested that it is impossible to conclude that the use of a bypass lane provides a greater degree of safety, and, therefore, bypass lanes should not be used as a safety device. There also were some concerns expressed about safety issues at four-legged intersections. Recommendations included: Revise Mn/DOT turn lane policies to at least reduce or eliminate the use of bypass lanes at four-legged intersections; Consider developing a shorter and less costly exclusive left turn lane design; and Offer designers positive guidance regarding the use of left-turn lanes, through a prioritized approach based on the functional classification of the major roadway.

Currently, many townships, cities and some rural counties do not have entrance policies and design standards. This report provides rationale on why access should be managed in rural areas. It also identifies fundamental planning principles, design guidelines and best management practices for lower-volume rural roadways. Additional information sources for developing or refining local policies are included. The study reviewed literature, conducted a survey of rural Minnesota counties, townships and cities and identified the following best management practices (BMPs): (1) Establish a formal access policy to determine the need and evaluate use, location and design of requested access points; (2) Encourage coordination during the zoning and platting process; (3) Adopt a policy that grants access for a specific use. If this use should change, a new access permit would be required; (4) Encourage adequate spacing of access points; (5) Protect the functional area of intersections in order to separate conflict areas (typically 480 to 820 feet from the intersection); (6) Ensure adequate sight distance at entrances; (7) Avoid offset or "dogleg" intersections and entrances; (8) Encourage turn lanes and bypass lanes (on higher speed roadways); (9) Consider providing shared access or relocating existing access; and (10) Encourage good driveway and intersection design characteristics.

In this study, we examine population and housing change, changes in industrial activity and occupational changes, and characteristics of commuters and the journey to work for those working away from home in 26 regional centers and their commute sheds in Greater Minnesota. We also explore ways in which Public Use Microdata Samples (PUMS) and Public Use Microdata Areas (PUMAs) might be exploited to shed additional insight into the changing nature of the demographic, economic and commuting patterns that are now pervasive throughout Greater Minnesota. These data are evaluated to explore links between demographic and economic features of working-age populations, and relationships between worker and household characteristics and aspects of commuting activity on the other. The final chapter examines regional economic vitality and travel behavior across the Minnesota Countryside. When population change in sample regional centers in the 1990s is compared with change in the nearby counties that comprise the centers' commuting fields, four situations appear: those where centers and their commuting fields both had population increases; centers with declining populations, but increases in the commuting fields; centers with growing populations, but with declines in their commuting fields; and situations where both the center and the commute field lost population.

Deployment of any system is driven by market demand and system cost. Initial deployment of the Intelligent Vehicle Lab Snowplow Driver Assistive System (DAS) was limited to a 45 mile section of Minnesota Trunk Highway 7 west of I-494 and east of Hutchinson MN. To better gage demand and functionality, St. Louis and Polk Counties in Minnesota operationally tested the system during the winter of 2003-2004; Polk County also tested during the winter of 2004-2005. Operational benefits were found to be drastically different in the two counties. Low visibility was not an issue with the St. Louis County snowplow routes, so the system offered few benefits. In contrast the topology of Polk county is flat, with almost no trees. High winds combined with few visual cues create significant low visibility conditions. Polk County was pleased with their original system, and obtained a second system and tested it operationally during the 2004-2005 winter. The experience of these two counties is documented in this volume, Volume One. A key component of the DAS is a high accuracy digital map. With the exception of the mapping process, the present cost of the DAS is well documented. Volume Two describes a system designed to collect and process geospatial data to be used by driver assistive system, and the costs and time associated with collecting map data, and creating a map from that data. With cost data complete, counties can determine whether to acquire these systems.

Deployment of any system is driven by market demand and system cost. Initial deployment of the Intelligent Vehicle Lab Snowplow Driver Assistive System (DAS) was limited to a 45 mile section of Minnesota Trunk Highway 7 west of I-494 and east of Hutchinson MN. To better gage demand and functionality, St. Louis and Polk Counties in Minnesota operationally tested the system during the winter of 2003-2004; Polk County also tested during the winter of 2004-2005. Operational benefits were found to be drastically different in the two counties. Low visibility was not an issue with the St. Louis County snowplow routes, so the system offered few benefits. In contrast the topology of Polk county is flat, with almost no trees. High winds combined with few visual cues create significant low visibility conditions. Polk County was pleased with their original system, and obtained a second system and tested it operationally during the 2004-2005 winter. The experience of these two counties is documented in Volume One. A key component of the DAS is a high accuracy digital map. With the exception of the mapping process, the present cost of the DAS is well documented. This volume, Volume Two, describes a system designed to collect and process geospatial data to be used by driver assistive system, and the costs and time associated with collecting map data, and creating a map from that data. With cost data complete, counties can determine whether to acquire these systems.