Browsing by Subject "Wireless communication systems"

Now showing 1 - 6 of 6
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    A Comprehensive System for Assessing Truck Parking Availability
    (Center for Transportation Studies, University of Minnesota, 2017-01) Morris, Ted; Murray, Dan; Fender, Kate; Weber, Amanda; Morellas, Vassilios; Cook, Doug; Papanikolopoulos, Nikos
    Commercial heavy vehicle (CHV) drivers are required under federal Hours of Services (HOS) rules to rest and take breaks to reduce driving while fatigued. CHV drivers and operators must balance compliance to the HOS rules against on-time delivery requirements as well as shorter lead times to plan their trips, thereby making location and parking availability of rest area facilities more critical. Without timely, accurate parking availability information, drivers are left with the dilemma of continuing to drive fatigued, drive beyond HOS CHV operation limits, or park illegally on highway shoulders or ramps—all potential safety hazards. In this study, a multi-view camera system was designed and evaluated to detect truck parking space occupancy in real-time through extensive field operational testing. A system architecture was then developed to disseminate up-to-the-minute truck parking information through three separate information delivery systems: 1) Roadside Changeable Message Signs (CMS), 2) Internet/Website information portal, and 3) an onboard geolocation application. The latter application informs the driver of parking availability of one or more parking facilities that are downstream from their current direction of travel. All three notification mechanisms were evaluated during the field test. Survey studies were conducted to provide feedback from commercial heavy vehicle drivers and operators to better understand their perceptions of parking shortages and utility of the parking information delivery mechanisms. Overall, the system has proven to provide 24/7 around-the-clock per-space parking status with no need for manual interventions to correct detection errors, with per parking space accuracy typically equal to or exceeding 95 percent. The concept of operations field tests demonstrated the feasibility of the technical approach and the potential to alter freight borne trip behaviors by allowing drivers and carriers to plan stops and improve trip efficiency.
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    Development of a New Tracking System Based on CMOS Vision Processor Hardware, Phase II Prototype Demonstration
    (Intelligent Transportation Systems Institute, Center for Transportation Studies, University of Minnesota, 2012-05) Tang, Hua; Peng, Li
    Intelligent transportation systems depend on being able to track vehicle operations and collect accurate traffic data. This project targets a hardware-based video detection system for real-time vehicle detection. To allow real-time detection, customized hardware implementation of the system is targeted instead on the traditional computer-based implementation of the system. The system includes four main processing steps. First, a camera is used to capture images. Second, the captured images are segmented using the Mixture-of-Gaussian algorithm. Without sacrificing the segmentation accuracy, researchers modified the Mixture-of-Gaussian algorithm to allow more efficient and economical hardware implementation in terms of design overhead and hardware resources. Third, the segmentation regions are extracted and validated as the objects of interests. In the last step, the validation result will be wirelessly transmitted to a variable message sign, which displays necessary traffic information. Since the system design includes integration of diverse devices, the video design kit from Xilinx is used. Such a hardware-based vehicle detection system has been experimented tested with practical videos of traffic scene.
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    Field Testing and Evaluation of a Wireless-Based Transit Signal Priority System
    (Intelligent Transportation Systems Institute, Center for Transportation Studies, 2011-10) Liao, Chen-Fu; Davis, Gary A.
    Most signal priority strategies implemented in various U.S. cities used sensors to detect buses at a fixed or preset distance away from an intersection. Traditional presence detection systems, ideally designed for emergency vehicles, usually send a signal priority request after a pre-programmed time offset as soon as transit vehicles are detected without the consideration of bus readiness. As part of the Urban Partnership Agreement, Metro Transit, Minnesota Department of Transportation (MnDOT), and the City of Minneapolis have implemented Transit Signal Priority (TSP) along Central Avenue from north Minneapolis (2nd Street SE) to south of I-694 (53rd Avenue NE) with total of 27 intersections. Transit performance before and after the deployment of a TSP strategy was examined through the data analysis process to evaluate the effectiveness and benefit of a TSP strategy. The objective of this study is to deploy and validate a wireless-based TSP strategy developed from earlier studies by considering bus schedule adherence, location and speed. A TSP onboard system using embedded computer was developed to interface with EMTRAC radio modules to bypass the EMTRAC TSP algorithm on current buses. Field experiments were performed by installing University of Minnesota (UMN) TSP units on four RTE10 buses for two weeks. The EMTRAC algorithm was temporary disabled on the test vehicles. Link travel time and node dwell time on the TSP-equipped route segments are compared. The results indicated the UMN TSP algorithm gain additional 3-6% of travel time reduction as compared to other RTE10 buses operating during the two-week test period.
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    ITS and Transportation Safety: EMS System Data Integration to Improve Traffic Crash Emergency Response and Treatment – Phase II Report
    (Intelligent Transportation Systems Institute, Center for Transportation Studies, 2011-08) Horan, Thomas A.; Schooley, Benjamin; McClintock, Roni; Lee, Yoonmi
    This research project examines the linkages between ITS systems and the SHSP, focusing on three elements. The first element relates to the role of ITS in producing timely data on safety dimensions, including its visual representation in geographic information systems and related platforms. The second element examines the use of ITS with emergency medical services (EMS) and the data that can be used from EMS systems for safety planning purposes. The third element includes an analysis of innovative and new practices for capturing, sharing, and visualizing safety information required by emergency healthcare providers for enhanced levels of decision making and planning.
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    Low-Cost Portable Video-Based Queue Detection for Work- Zone Safety
    (2011-01) Morris, Ted; Schwach, Jory A.; Michalopoulos, Panos G.
    Highway work-zone safety is a major concern for government agencies, the legislature, and the traveling public. Several work zone intelligent transportation systems (WZITS) have been developed as a safety countermeasure to warn drivers of dangerous traffic conditions. Unfortunately, the effectiveness of a WZTIS is diminished if the actual traffic flow conditions do not correspond with the sensor information leading to false warnings; these confuse drivers and reduce the credibility of the system, which is often ignored. This can lead to situations where drivers crash into work-zone areas because they are unprepared to stop. The national cost of crashes due to this was estimated to be nearly $2.5 billion. Such “dangerous” traffic conditions are typically characterized by unpredictable queue formations that propagate rapidly into higher speed traffic immediately upstream from the active work zone. False positives or missed warnings could be reduced if the location of queue tails in addition to vehicle speeds in proximity to the active work zone can be accurately detected. In this study, a low-cost rapidly deployable and portable queue detection WZITS warning system is proposed. To demonstrate WZITS feasibility, a queue detection algorithm was designed and tested using widely available, field proven, machine vision hardware that can be integrated into the current portable system prototype, using video data collected in the field from the portable device. The warning trigger generated by the algorithm can then be transmitted to a remote upstream location for triggering roadside emergency warning devices (such as VMS, flashers, etc.).
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    Rapidly Deployable Low-Cost Traffic Data and Video Collection Device
    (University of Minnesota Center for Transportation Studies, 2009-12) Schwach, Joey; Morris, Ted; Michalopoulos, Panos G.
    Transportation practitioners, planners and researchers lack the availability of an easily deployable, non-intrusive, portable, low-cost device for traffic data collection and video recording at intersections and arterials as well as temporary remote surveillance. The necessary data usually includes volumes, speeds, classification, turning movements, queue size and length, conflicting movements, and time headways. They also include recording of traffic characteristics, accidents and other special situations. A visual record of traffic characteristics at intersections, arterials, or other locations can also be used for extensive analysis and research leading to improved safety and control practices. In this report, the development and demonstration of a low-cost, practical, rapidly deployable video recording and data collection device is presented along with the design, deployment, and data extraction process. Its major advantage at intersections is that only one unit can cover an entire intersection up to 5 lanes per incoming approach wide (20 incoming lanes total), which should be sufficient for the overwhelming majority of intersections. In addition it has the potential of extracting turning movements automatically including optional lanes through advanced machine vision or radar sensors.