2,114 research outputs found

    Implementation and Evaluation of a Cooperative Vehicle-to-Pedestrian Safety Application

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    While the development of Vehicle-to-Vehicle (V2V) safety applications based on Dedicated Short-Range Communications (DSRC) has been extensively undergoing standardization for more than a decade, such applications are extremely missing for Vulnerable Road Users (VRUs). Nonexistence of collaborative systems between VRUs and vehicles was the main reason for this lack of attention. Recent developments in Wi-Fi Direct and DSRC-enabled smartphones are changing this perspective. Leveraging the existing V2V platforms, we propose a new framework using a DSRC-enabled smartphone to extend safety benefits to VRUs. The interoperability of applications between vehicles and portable DSRC enabled devices is achieved through the SAE J2735 Personal Safety Message (PSM). However, considering the fact that VRU movement dynamics, response times, and crash scenarios are fundamentally different from vehicles, a specific framework should be designed for VRU safety applications to study their performance. In this article, we first propose an end-to-end Vehicle-to-Pedestrian (V2P) framework to provide situational awareness and hazard detection based on the most common and injury-prone crash scenarios. The details of our VRU safety module, including target classification and collision detection algorithms, are explained next. Furthermore, we propose and evaluate a mitigating solution for congestion and power consumption issues in such systems. Finally, the whole system is implemented and analyzed for realistic crash scenarios

    Methodology for development of drought Severity-Duration-Frequency (SDF) Curves

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    Drought monitoring and early warning are essential elements impacting drought sensitive sectors such as primary production, industrial and consumptive water users. A quantitative estimate of the probability of occurrence and the anticipated severity of drought is crucial for the development of mitigating strategies. The overall aim of this study is to develop a methodology to assess drought frequency and severity and to advance the understanding of monitoring and predicting droughts in the future. Seventy (70) meteorological stations across Victoria, Australia were selected for analysis. To achieve the above objective, the analysis was initially carried out to select the most applicable meteorological drought index for Victoria. This is important because to date, no drought indices are applied across Australia by any Commonwealth agency quantifying drought impacts. An evaluation of existing meteorological drought indices namely, the Standardised Precipitation Index (SPI), the Reconnaissance Drought Index (RDI) and Deciles was first conducted to assess their suitability for the determination of drought conditions. The use of the Standardised Precipitation Index (SPI) was shown to be satisfactory for assessing and monitoring meteorological droughts in Australia. When applied to data, SPI was also successful in detecting the onset and the end of historical droughts. Temporal changes in historic rainfall variability and the trend of SPI were investigated using non-parametric trend techniques to detect wet and dry periods across Victoria, Australia. The first part of the analysis was carried out to determine annual rainfall trends using Mann Kendall (MK) and Sen’s slope tests at five selected meteorological stations with long historical records (more than 100 years), as well as a short sub-set period (1949-2011) of the same data set. It was found that different trend results were obtained for the sub-set. For SPI trend analysis, it was observed that, although different results were obtained showing significant trends, SPI gave a trend direction similar to annual precipitation (downward and upward trends). In addition, temporal trends in the rate of occurrence of drought events (i.e. inter-arrival times) were examined. The fact that most of the stations showed negative slopes indicated that the intervals between events were becoming shorter and the frequency of events was temporally increasing. Based on the results obtained from the preliminary analysis, the trend analyses were then carried out for the remaining 65 stations. The main conclusions from these analyses are summarized as follows; 1) the trend analysis was observed to be highly dependent on the start and end dates of analysis. It is recommended that in the selection of time period for the drought, trend analysis should consider the length xvi of available data sets. Longer data series would give more meaningful results, thus improving the understanding of droughts impacted by climate change. 2) From the SPI and inter-arrival drought trends, it was observed that some of the study areas in Victoria will face more frequent dry period leading to increased drought occurrence. Information similar to this would be very important to develop suitable strategies to mitigate the impacts of future droughts. The main objective of this study was the development of a methodology to assess drought risk for each region based on a frequency analysis of the drought severity series using the SPI index calculated over a 12-month duration. A novel concept centric on drought severity-duration-frequency (SDF) curves was successfully derived for all the 70 stations using an innovative threshold approach. The methodology derived using extreme value analysis will assist in the characterization of droughts and provide useful information to policy makers and agencies developing drought response plans. Using regionalisation techniques such as Cluster analysis and modified Andrews curve, the study area was separated into homogenous groups based on rainfall characteristics. In the current Victorian application the study area was separated into six homogeneous clusters with unique signatures. A set of mean SDF curves was developed for each cluster to identify the frequency and severity of the risk of drought events for various return periods in each cluster. The advantage of developing a mean SDF curve (as a signature) for each cluster is that it assists the understanding of drought conditions for an ungauged or unknown station, the characteristics of which fit existing cluster groups. Non-homogeneous Markov Chain modelling was used to estimate the probability of different drought severity classes and drought severity class predictions 1, 2 and 3 months ahead. The non-homogeneous formulation, which considers the seasonality of precipitation, is useful for understanding the evolution of drought events and for short-term planning. Overall, this model predicted drought situations 1 month ahead well. However, predictions 2 and 3 months ahead should be used with caution. Many parts of Australia including Victoria have experienced their worst droughts on record over the last decade. With the threat of climate change potentially further exacerbating droughts in the years ahead, a clear understanding of the impact of droughts is vital. The information on the probability of occurrence and the anticipated severity of drought will be helpful for water resources managers, infrastructure planners and government policy-makers with future infrastructure planning and with the design and building of more resilient communities

    Automated Mixed Traffic Vehicle (AMTV) technology and safety study

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    Technology and safety related to the implementation of an Automated Mixed Traffic Vehicle (AMTV) system are discussed. System concepts and technology status were reviewed and areas where further development is needed are identified. Failure and hazard modes were also analyzed and methods for prevention were suggested. The results presented are intended as a guide for further efforts in AMTV system design and technology development for both near term and long term applications. The AMTV systems discussed include a low speed system, and a hybrid system consisting of low speed sections and high speed sections operating in a semi-guideway. The safety analysis identified hazards that may arise in a properly functioning AMTV system, as well as hardware failure modes. Safety related failure modes were emphasized. A risk assessment was performed in order to create a priority order and significant hazards and failure modes were summarized. Corrective measures were proposed for each hazard

    Safe Intelligent Driver Assistance System in V2X Communication Environments based on IoT

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    In the modern world, power and speed of cars have increased steadily, as traffic continued to increase. At the same time highway-related fatalities and injuries due to road incidents are constantly growing and safety problems come first. Therefore, the development of Driver Assistance Systems (DAS) has become a major issue. Numerous innovations, systems and technologies have been developed in order to improve road transportation and safety. Modern computer vision algorithms enable cars to understand the road environment with low miss rates. A number of Intelligent Transportation Systems (ITSs), Vehicle Ad-Hoc Networks (VANETs) have been applied in the different cities over the world. Recently, a new global paradigm, known as the Internet of Things (IoT) brings new idea to update the existing solutions. Vehicle-to-Infrastructure communication based on IoT technologies would be a next step in intelligent transportation for the future Internet-of-Vehicles (IoV). The overall purpose of this research was to come up with a scalable IoT solution for driver assistance, which allows to combine safety relevant information for a driver from different types of in-vehicle sensors, in-vehicle DAS, vehicle networks and driver`s gadgets. This study brushed up on the evolution and state-of-the-art of Vehicle Systems. Existing ITSs, VANETs and DASs were evaluated in the research. The study proposed a design approach for the future development of transport systems applying IoT paradigm to the transport safety applications in order to enable driver assistance become part of Internet of Vehicles (IoV). The research proposed the architecture of the Safe Intelligent DAS (SiDAS) based on IoT V2X communications in order to combine different types of data from different available devices and vehicle systems. The research proposed IoT ARM structure for SiDAS, data flow diagrams, protocols. The study proposes several IoT system structures for the vehicle-pedestrian and vehicle-vehicle collision prediction as case studies for the flexible SiDAS framework architecture. The research has demonstrated the significant increase in driver situation awareness by using IoT SiDAS, especially in NLOS conditions. Moreover, the time analysis, taking into account IoT, Cloud, LTE and DSRS latency, has been provided for different collision scenarios, in order to evaluate the overall system latency and ensure applicability for real-time driver emergency notification. Experimental results demonstrate that the proposed SiDAS improves traffic safety

    Route Segment Level Analysis of Bus Safety Incidents

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    This paper analyzes collision and non-collision incidents that occurred on TriMet’s bus system over a near two-year period. The bus route network was decomposed into stop and line haul segments, and a typology of models was estimated from segment level incident, risk exposure, and roadway feature data. The frequency of non-collision incidents – mainly slips, trips and falls – was estimated to be primarily related to associated risk exposure variables. The frequency of collision incidents was also estimated to be related to risk exposure variables, as well as a number of roadway design variables. The findings serve as an initial step in informing the safety planning process

    FESTA. D4 Common vision regarding cooperative systems FOTs

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    The objective of an FOT is to evaluate in-vehicle functions based on Information Communication Technology (ICT) in order to address specific research questions. These research questions can be related to safety, environment, mobility, traffic efficiency, usage, and acceptance. By addressing the research questions, FOTs promise to furnish the major stakeholders (customers, public authorities, OEMs, suppliers, and the scientific community) with valuable information able to improve their policy-making and market strategies. Individuating the most relevant functions and connected hypothesis to successfully address the above-mentioned research questions is one of the major challenges in an FOT. In this deliverable, the process of individuating the vehicle functions to be tested in an FOT and the relevant connected hypotheses will be elucidated. Specifically, the reader will be guided in the process of 1) selecting the vehicle functions to be tested, 2) defining the connected use cases to test these vehicle functions, 3) identifying the research questions related to these use cases, 4) formulating the hypothesis associated to these research questions, and 5) linking these hypothesis to the correspondent performance indicators

    An Active Safety System for Low-Speed Bus Braking Assistance

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    Accidents in which buses or coaches are involved cause thousands of injuries and fatalities every year. To reduce their number and severity, the paper describes an Advanced Driver Assistance Systems (ADAS) based on a haptic throttle pedal and emergency braking. It also proposes a computationally efficient algorithm with a methodology based on three main concepts: a simplified but accurate vehicle model; an efficient collision detection system considering driver's intention and pedestrians wandering around the vehicle; and a risk evaluation system to generate warnings and emergency braking signals. Finally, the performance of the proposed ADAS is validated using a driving simulation cabin with a very realistic urban scenario and original elements from real buses. The results show a statistically significant improvement in safety, as the number of collisions and high risk situations are clearly minimized, reaction time to press the brake pedal is improved and time to collision increased in emergency situations. Implementation of the proposed ADAS into city buses would potentially improve safety, reducing the frequency and severity of accidents with pedestrians.This work was supported in part by Ministry of Science and Innovation of Spain through the SAFEBUS Project "Sistemas Avanzados de Seguridad Integral en Autobuses" under Grant IPT-2011-1165-370000 and the SAFETRANS Project "Sistemas de Conduccion Segura de Vehiculos de Transporte de Pasajeros y Materiales con Asistencia Haptica/Audiovisual e Interfaces Biomedicas" under Grant DPI2013-42302-R and in part by the Generalitat Valenciana, Programa VALi+d (ACIF/2010/206). The Associate Editor for this paper was E. Kosmatopoulos.Girbés, V.; Armesto Ángel, L.; Dols Ruiz, JF.; Tornero Montserrat, J. (2017). An Active Safety System for Low-Speed Bus Braking Assistance. IEEE Transactions on Intelligent Transportation Systems. 18(2):377-387. https://doi.org/10.1109/TITS.2016.2573921S37738718

    INTELLIGENTE TRANSPORT SYSTEMEN ITS EN VERKEERSVEILIGHEID

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    This report discusses Intelligent Transport Systems (ITS). This generic term is used for a broad range of information-, control- and electronic technology that can be integrated in the road infrastructure and the vehicles themselves, saving lives, time and money bymonitoring and managing traffic flows, reducing conges-tion, avoiding accidents, etc. Because this report was written in the scope of the Policy Research Centre Mobility & Public Works, track Traffic Safety, it focuses on ITS systems from the traffic safety point of view. Within the whole range of ITS systems, two categories can be distinguished: autonomous and cooperative systems. Autonomous systems are all forms of ITS which operate by itself, and do not depend on the cooperation with other vehicles or supporting infrastructure. Example applications are blind spot detection using radar, electronic stability control, dynamic traffic management using variable road signs, emergency call, etc. Cooperative systems are ITS systems based on communication and cooperation, both between vehicles as between vehicles and infrastructure. Example applications are alerting vehicles approaching a traffic jam, exchanging data regarding hazardous road conditions, extended electronic brake light, etc. In some cases, autonomous systems can evolve to autonomous cooperative systems. ISA (Intelligent Speed Adaptation) is an example of this: the dynamic aspect as well as communication with infrastructure (eg Traffic lights, Variable Message Sign (VMS)...) can provide additional road safety. This is the clear link between the two parts of this report. The many ITS applications are an indicator of the high expectations from the government, the academic world and the industry regarding the possibilities made possible by both categories of ITS systems. Therefore, the comprehensive discussion of both of them is the core of this report. The first part of the report covering the autonomous systems treats two aspects: 1. Overview of European projects related to mobility and in particular to road safety 2. Overview for guidelines for the evaluation of ITS projects. Out of the wide range of diverse (autonomous) ITS applications a selection is made; this selection is focused on E Safety Forum and PreVENT. Especially the PreVent research project is interesting because ITS-applications have led to a number of concrete demonstration vehicles that showed - in protected and unprotected surroundings- that these ITS-applications are already technically useful or could be developed into useful products. The component “guidelines for the evaluation of ITS projects” outlines that the government has to have specific evaluation tools if the government has the ambition of using ITS-applications for road safety. Two projects -guidelines for the evaluation of ITS projects- are examined; a third evaluation method is only mentioned because this description shows that a specific targeting of the government can be desirable : 1. TRACE describes the guidelines for the evaluation of ITS projects which are useful for the evaluation of specific ITS-applications. 2. FITS contains Finnish guidelines for the evaluation of ITS project; FIS is an adaptation of methods used for evaluation of transport projects. 3. The third evaluation method for the evaluation of ITS projects is developed in an ongoing European research project, eImpact. eImpact is important because, a specific consultation of stake holders shows that the social importance of some techniques is underestimated. These preliminary results show that an appropriate guiding role for the government could be important. In the second part of this document the cooperative systems are discussed in depth. These systems enable a large number of applications with an important social relevance, both on the level of the environment, mobility and traffic safety. Cooperative systems make it possible to warn drivers in time to avoid collisions (e.g. when approaching the tail of a traffic jam, or when a ghost driver is detected). Hazardous road conditions can be automatically communicated to other drivers (e.g. after the detection of black ice or an oil trail by the ESP). Navigation systems can receive detailed real-time up-dates about the current traffic situation and can take this into account when calculating their routes. When a traffic distortion occurs, traffic centers can immediately take action and can actively influence the way that the traffic will be diverted. Drivers can be notified well in advance about approaching emergency vehicles, and can be directed to yield way in a uniform manner. This is just a small selection from the large number of applications that are made possible because of cooperative ITS systems, but it is very obvious that these systems can make a significant positive contribution to traffic safety. In literature it is estimated that the decrease of accidents with injuries of fatalities will be between 20% and 50% . It is not suprising that ITS systems receive a lot of attention for the moment. On an international level, a number of standards are being established regarding this topic. The International Telecommunications Uniont (ITU), Institute for Electrical and Electronics Engineers (IEEE), International Organization for Standardization (ISO), Association of Radio Industries and Business (ARIB) and European committee for standardization (CEN) are currently defining standards that describe different aspects of ITS systems. One of the names that is mostly mentioned in literature is the ISO TC204/WG16 Communications Architecture for Land Mobile environment (CALM) standard. It describes a framework that enables transparent (both for the application and the user) continuous communication through different communication media. Besides the innumerable standardization activities, there is a great number of active research projects. On European level, the most important are the i2010 Intelligent Car Initiative, the eSafety Forum, and the COMeSafety, the CVIS, the SAFESPOT, the COOPERS and the SEVECOM project. The i2010 Intelligent Car Initiative is an European initiative with the goal to halve the number of traffic casualties by 2010. The eSafety Forum is an initiative of the European Commission, industry and other stakeholders and targets the acceleration of development and deployment of safety-related ITS systems. The COMeSafety project supports the eSafety Forum on the field of vehicle-to-vehicle and vehicle-to-infrastructure communication. In the CVIS project, attention is given to both technical and non-technical issues, with the main goal to develop the first free and open reference implementation of the CALM architecture. The SAFEST project investigates which data is important for safety applications, and with which algorithmsthis data can be extracted from vehicles and infrastructure. The COOPERS project mainly targets communication between vehicles and dedicated roadside infrastructure. Finally, the SEVECOM project researches security and privacy issues. Besides the European projects, research is also conducted in the United States of America (CICAS and VII projects) and in Japan (AHSRA, VICS, Smartway, internetITS). Besides standardization bodies and governmental organizations, also the industry has a considerable interest in ITS systems. In the scope of their ITS activities, a number of companies are united in national and international organizations. On an international level, the best known names are the Car 2 Car Communication Consortium, and Ertico. The C2C CC unites the large European car manufacturers, and focuses on the development of an open standard for vehicle-to-vehicle and vehicle-to-infrastructure communications based on the already well established IEEE 802.11 WLAN standard. Ertico is an European multi-sector, public/private partnership with the intended purpose of the development and introduction of ITS systems. On a national level, FlandersDrive and The Telematics Cluster / ITS Belgium are the best known organizations. Despite the worldwide activities regarding (cooperative) ITS systems, there still is no consensus about the wireless technology to be used in such systems. This can be put down to the fact that a large number of suitable technologies exist or are under development. Each technology has its specific advantages and disadvantages, but no single technology is the ideal solution for every ITS application. However, the different candidates can be classified in three distinct categories. The first group contains solutions for Dedicated Short Range Communication (DSRC), such as the WAVE technology. The second group is made up of several cellular communication networks providing coverage over wide areas. Examples are GPRS (data communication using the GSM network), UMTS (faster then GPRS), WiMAX (even faster then UMTS) and MBWA (similar to WiMAX). The third group consists of digital data broadcast technologies such as RDS (via the current FM radio transmissions, slow), DAB and DMB (via current digital radio transmissions, quicker) and DVB-H (via future digital television transmissions for mobiledevices, quickest). The previous makes it clear that ITS systems are a hot topic right now, and they receive a lot of attention from the academic world, the standardization bodies and the industry. Therefore, it seems like that it is just a matter of time before ITS systems will find their way into the daily live. Due to the large number of suitable technologies for the implementation of cooperative ITS systems, it is very hard to define which role the government has to play in these developments, and which are the next steps to take. These issues were addressed in reports produced by the i2010 Intelligent Car Initiative and the CVIS project. Their state of the art overview revealed that until now, no country has successfully deployed a fully operational ITS system yet. Seven EU countries are the furthest and are already in the deployment phase: Sweden, Germany, the Netherlands, the United Kingdom, Finland, Spain and France. These countries are trailed by eight countries which are in the promotion phase: Denmark, Greece, Italy, Austria, Belgium,Norway, the Czech Republic and Poland. Finally, the last ten countries find themselves in the start-up phase: Estonia, Lithuania, Latvia, Slovenia, Slovakia, Hungary, Portugal, Switzerland, Ireland and Luxembourg. These European reports produced by the i2010 Intelligent Car Initiative and the CVIS project have defined a few policy recommendations which are very relevant for the Belgian and Flemish government. The most important recommendations for the Flemish government are: • Support awareness: research revealed that civilians consider ITS applications useful, but they are not really willing to pay for this technology. Therefore, it is important to convince the general public of the usefulness and the importance of ITS systems. • Fill the gaps: Belgium is situated in the promotion phase. This means that it should focus at identifying the missing stakeholders, and coordinating national and regional ITS activities. Here it is important that the research activities are coordinated in a national and international context to allow transfer of knowledge from one study to the next, as well as the results to be comparable. • Develop a vision: in the scope of ITS systems policies have to be defined regarding a large number of issues. For instance there is the question if ITS users should be educated, meaning that the use of ITS systems should be the subject of the drivers license exam. How will the regulations be for the technical inspection of vehicles equipped with ITS technology? Will ITS systems be deployed on a voluntary base, or will they e.g. be obliged in every new car? Will the services be offered by private companies, by the public authorities, or by a combination of them? Which technology will be used to implement ITS systems? These are just a few of the many questions where the government will have to develop a point of view for. • Policy coordination: ITS systems are a policy subject on an international, national and regional level. It is very important that these policy organizations can collaborate in a coordinated manner. • Iterative approach to policy development: developing policies for this complex matter is not a simple task. This asks for an iterative approach, where policy decisions are continuously refined and adjusted
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