Browsing by Subject "Automobile drivers"

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    Determination of the Alert and Warning Timing for the Cooperative Intersection Collision Avoidance System-Stop Sign Assist Using Macroscopic and Microscopic Data: CICAS-SSA Report #1
    (2010-08) Gorjestani, Alec; Menon, Arvind; Cheng, Pi-Ming; Shankwitz, Craig; Donath, Max
    Crashes at rural thru-stop intersections arise primarily from a driver attempting to cross or enter the mainline traffic stream after failing to recognize an unsafe gap condition. Because the primary cause of these crashes is not failure to stop, but failure to recognize an unsafe condition, the US DOT FHWA, MnDOT, and the University of Minnesota ITS Institute undertook the Cooperative Intersection Collision Avoidance System – Stop Sign Assist (CICAS-SSA) program. CICAS-SSA uses roadside radar sensors, a computer processor and algorithms to determine unsafe conditions, and an active LED icon based sign to provide timely alerts and warnings which are designed to reduce the frequency of crashes at rural expressway intersections. The focus of this report is the alert and warning timing used to provide a driver with assistance in recognizing and taking appropriate action when presented a gap which could be considered unsafe. The work presented herein uses both macroscopic data collected by roadside sensors and data acquisition equipment in Minnesota, Wisconsin, and North Carolina, and microscopic data collected using an instrumented vehicle and test subjects at the Minnesota Research Intersection, located at the intersection of US Hwy 52 and Goodhue County Road 9. Three tenets that are particularly germane to the determination of alert and warning timing for the CICAS-SSA system are: (1) the system does not help a driver choose a safe gap; it is designed to assist a driver with unsafe gap rejection, (2) it indicates when it is unsafe to proceed, not when it is safe to proceed, and (3) it must complement good decision making, and address those instances where poor decision making could lead to a crash.
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    Macroscopic Review of Driver Gap Acceptance and Rejection Behavior at Rural Thru-Stop Intersections in the US - Data Collection Results in Eight States: CICAS-SSA Report #3
    (2010-08) Gorjestani, Alec; Menon, Arvind; Cheng, Pi-Ming; Newstrom, Bryan; Shankwitz, Craig; Donath, Max
    Crashes at rural thru-stop intersections arise primarily from a driver attempting to cross or enter the mainline traffic stream after failing to recognize an unsafe gap condition. Because the primary cause of these crashes is not failure to stop, but failure to recognize an unsafe condition, the US DOT FHWA, MnDOT, and the University of Minnesota ITS Institute undertook the CICAS-SSA program. CICAS-SSA uses roadside radar sensors, a computer processor and algorithms to determine unsafe conditions, and an active LED icon based sign to provide timely alerts and warnings which are designed to reduce the frequency of crashes at rural expressway intersections. These rural, thru-stop crashes are problems in many states. In conjunction with the CICAS-SSA program, MnDOT and the University of Minnesota led a nine-state (CA, GA, IA, MI, MN, NC, NH, NV, and WI) pooledfund study whereby driver behavior data at rural thru-stop intersections was collected by the Minnesota Mobile Intersection Surveillance System (MMISS). The ultimate goal of the pooled fund study and the analysis of that data described here, was to identify whether drivers in different regions of the county exhibit different gap acceptance/rejection behavior, and if different driver behaviors are identified, determine whether they are different enough to inhibit the deployment of a common CICAS-SSA design throughout the US. The analysis of the data indicated that the system can indeed be deployed nationally.
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    Performance Analysis of Squad Car Lighting, Retro-reflective Markings, and Paint Treatments to Improve Safety at Roadside Traffic Stops
    (Intelligent Transportation Systems Institute, Center for Transportation Studies, University of Minnesota, 2012-05) Fischer, Jacob; Krzmarzick, Adam; Menon, Arvind; Shankwitz, Craig
    In the United States, more police officers are killed in collisions at roadside stops than through felonious acts. Causal factors that affect police safety at roadside stops include officer conspicuity, squad conspicuity, weather conditions, and the attention and fatigue level of the traveling public. Described herein is a research project that provides insight and guidelines that may ultimately improve officer safety at roadside stops. The project is designed to modify an existing sensor-based traffic monitoring system so that it serves as a test bed to evaluate the retro-reflector, lighting, and paint treatments of an emergency vehicle to determine whether particular combinations produce improved “move over” behavior of oncoming traffic. This is done using automated data analysis software built specifically for this project. Tests are performed at a fully instrumented rural intersection. After mimicking a traffic stop where a patrol vehicle is placed at this intersection, the experimenter logs onto a website and enters the time when the test took place. Analysis software draws results from the data. The results are e-mailed to the experimenters, who devise their own test regimes, following the guidelines presented herein, and draw their own conclusions. A second system was built to provide a more portable option for testing in urban areas. This system consists of two freestanding radar boxes with wireless communication, as well as one netbook computer. Test procedures and results are analogous to the original system. Additional calibration is automatically performed to account for the variable position of the radars.
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    Sign Comprehension, Considering Rotation and Location, Using Random Gap Simulation for a Cooperative Intersection Collision Avoidance System – Stop Sign Assist: CICAS-SSA Report #4
    (2010-08) Creaser, Janet; Manser, Michael; Rakauskas, Michael; Donath, Max
    Crashes at rural thru-stop intersections arise primarily from a driver attempting to cross or enter the mainline traffic stream after failing to recognize an unsafe gap condition. Because the primary cause of these crashes is not failure to stop, but failure to recognize an unsafe condition, the US DOT FHWA, MnDOT, and the University of Minnesota ITS Institute undertook the CICAS-SSA program. CICAS-SSA uses roadside radar sensors, a computer processor and algorithms to determine unsafe conditions, and an active LED icon based sign to provide timely alerts and warnings which are designed to reduce the frequency of crashes at rural expressway intersections. The primary goal of this portion of the overall effort was to evaluate several candidate CICAS-SSA concepts in order to identify a single sign that may provide the greatest utility in terms of driver performance and usability at a real-world rural intersection. A secondary goal of the work was to determine the ideal physical characteristics (i.e., location and rotation of a sign relative to drivers) of the candidate CICAS-SSA at a test intersection to maximize comprehension (and subsequent use) of the sign. This report summarizes the results of the work.
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    Validation Study – On-Road Evaluation of the Cooperative Intersection Collision Avoidance System – Stop Sign Assist Sign: CICAS-SSA Report #5
    (2010-08) Rakauskas, Michael; Creaser, Janet; Manser, Michael; Graving, Justin; Donath, Max
    The CICAS-SSA sign is a roadside driver support system that is intended to improve gap rejection at rural stopcontrolled intersections. The CICAS-SSA system tracks vehicle locations on a major roadway and then displays a message to a driver on the minor road via an active LED icon-based sign. The basis of this sign is a “Divided Highway” sign that is commonly presented in traffic environments. Overlaid on the roadways of the sign are yellow or red icons that represent approaching vehicles that are at a distance at which the driver on the minor road should proceed with caution or at a distance that is considered unsafe to enter the intersection. Previous research conducted in a driving simulation environment indicated potentially beneficial changes in driver decision-making relative to approaching vehicle gap sizes and indicated that drivers perceive the system as being both useful and satisfying. While simulation-based evaluations provide a wealth of useful information, their ability to replicate the full array of behavioral, cognitive, and perceptual elements of a driving environment do have some limitations. It is because of these limitations that it is useful to confirm simulation-based findings in a real-world environment. The primary goal of the current work was to evaluate the candidate CICAS-SSA sign in a real-world setting to confirm previously identified benefits and identify any unintended consequences of sign usage. This goal was accomplished through a validation field test performed at the intersection of US Highway 52 and County Road 9 in Southern Minnesota. The findings of the work are summarized in this report.