In this thesis, an infrastructure informed index is developed for pedestrians and bicyclists to relate the natural and built environment with its impact on perceived travel distance and time. The objective is to develop an easy to use metric for use at all levels, allowing transportation planners to make better informed decisions when planning or redeveloping a city or area. Building off of similar research efforts, attributes are determined and weighted to capture the characteristics of a link, then summed to create the infrastructure informed index for pedestrians and bicyclists, respectively. These indices are then visualized using ArcGIS mapping tools, creating a service area around specific origin or destination points to see the effective area a pedestrian or bicyclist can travel taking into account the effects of the infrastructure along the route. / text

Fatal vehicle-bicycle crashes have increased in the United States while cyclist crashes often go unreported. The underreporting of all cyclist crashes results in the overall pre-crash behavior of the cyclists being unknown. What is known is that the most fatal bicycle crash scenario occurs when a vehicle performs an overtaking maneuver. It is crucial to find effective strategies to mitigate these crashes. Vision Zero aims to eliminate all traffic fatalities and disabling injuries by the year 2050 through the implementation of the safe system approach. One of their approaches is using active safety systems like bicycle detecting automatic emergency braking. The purpose of this study was to characterize bicyclist behavior to enhance the crash avoidance potential of advanced driver assistance systems and improve safety for cyclists. An analysis on fatal crashes involving bicyclists was conducted to determine scenarios for testing bicyclist-vehicle interactions on roadways using virtual reality (VR). VR testing was conducted to capture and analyze bicyclist dynamics. Most fatal bicycle crashes occurred when motorists overtook cyclists, especially when cyclists are travelling in a travel lane in the same direction as traffic. These crashes often happen in densely populated areas with favorable weather conditions. This information was used to construct scenarios representing common fatal bicycle crash scenarios. From the analysis, four scenarios were developed. The first scenario was an overtaking scenario with the cyclist traveling in the same direction as traffic, in a travel lane without a bicycle lane or shoulder. The second, third and fourth scenarios were variations of the first to include a bike lane, shoulder, and both a bike lane and a shoulder to analyze the behavior difference due to the inclusion of each. Participants were immersed in a VR simulator that used the combination of a VR headset and a custom-built stationary bicycle. Eighteen individuals were recruited with an average age of 22.7 years. Participants experienced all four scenarios, and their speed, glance, lane position, and standard deviation of lane position were collected and analyzed. The speed for each road type and overtaking phase did not vary significantly, with an average of 4.9 m/s. In the case where there was neither a bike lane or a shoulder, the cyclists looked towards the vehicle more than the other scenarios. As for the lane position, the scenario where the cyclist had neither a shoulder or a bike lane, led to a closer vehicle-bicycle relative position than the other three scenarios. As for standard deviation of lane position, the road with neither a shoulder or bike lane had the largest interquartile range (IQR) and average and the road with both a shoulder and bike lane had the smallest IQR. This implies a lower predictability of the cyclist's movements when they are riding on a roadway with no support lane. Following the testing, participants rated the perceived realism and interactiveness of the VR world and their comfort in each road design. Most of the participants mentioned that having some allocated space felt more comfortable and lowered their sense of danger. To enhance cyclist safety, adopting Euro NCAP testing for AEB systems in the US is recommended. This form of testing could lead to improvements in AEB systems, reducing crashes with cyclists and injury severity. In terms of road infrastructure improvements increasing the number of bike lanes, adding wider shoulders, or widening lanes could also enhance cyclist safety on roadways. / Master of Science / Fatal crashes between vehicles and bicycles have increased in the United States while cyclist crashes often go unreported. The underreporting of all cyclist crashes results in the overall pre-crash behavior of the cyclists being unknown. What is known is that the most fatal bicycle crash scenario occurs when a vehicle performs an overtaking maneuver. It is crucial to find effective strategies to reduce the severity and occurrences of these crashes. A traffic safety initiative called Vision Zero aims to eliminate all traffic fatalities and disabling injuries by the year 2050 through the implementation of the safe system approach. One of their approaches is having technology installed in vehicles to assist drivers in mitigating accidents, such as bicycle detecting automatic emergency braking. The purpose of this study was to characterize bicyclist behavior to enhance the crash avoidance potential of advanced driver assistance systems and improve safety for cyclists. An analysis on fatal crashes involving bicyclists was conducted to determine scenarios for testing bicyclist-vehicle interactions on roadways using virtual reality (VR). VR testing was conducted to capture and analyze bicyclist dynamics. Most fatal bicycle crashes occurred when motorists overtook cyclists, especially when cyclists are travelling in a travel lane in the same direction as traffic. Overtaking is when a vehicle is travelling faster than the cyclist and passes them. Crashes between vehicles and bicycles often happen in densely populated areas with favorable weather conditions. This information was used to construct scenarios representing common fatal bicycle crash scenarios. From the analysis, four scenarios were developed. The first scenario was an overtaking scenario with the cyclist traveling in the same direction as traffic, in a travel lane without a bicycle lane or shoulder. The second, third and fourth scenarios were variations of the first to include a bike lane, shoulder, and both a bike lane and a shoulder to analyze the behavior difference due to the inclusion of each. Where the shoulder is additional paved area alongside the travel lane. Participants were immersed in a VR simulator that used the combination of a VR headset and a custom-built stationary bicycle. Eighteen individuals were recruited with an average age of 22.7 years. Participants experienced all four scenarios, and their speed, glance, lane position, and standard deviation of lane position were collected and analyzed. The speed for each road type and overtaking phase did not vary significantly, with an average of 4.9 m/s. In the case where there was neither a bike lane or a shoulder, the cyclists looked towards the vehicle more than the other scenarios. As for the lane position, the scenario where the cyclist had neither a shoulder or a bike lane, led to a closer relative position between the vehicles and bicyclists than the other three scenarios. As for standard deviation of lane position or lateral movement, the road with neither a shoulder or bike lane had the largest interquartile range (IQR) and average and the road with both a shoulder and bike lane had the smallest IQR. Where IQR is the statistical measure indicating the dispersion of data between the first quartile and the third quartile. This implies a lower predictability of the cyclist's movements when they are riding on a roadway with no support lane. Following the testing, participants rated the perceived realism and interactiveness of the VR world and their comfort in each road design. Most of the participants mentioned that having some allocated space felt more comfortable and lowered their sense of danger. To enhance cyclist safety, adopting the European New Car Assessment Program (Euro NCAP) testing for automatic emergency braking systems in the US is recommended. This form of testing could lead to improvements in automatic emergency braking systems, reducing crashes with cyclists and injury severity. For road infrastructure improvements increasing the number of bike lanes, adding wider shoulders, or widening lanes could also enhance cyclist safety on roadways.

In view of the expected increase in the proportion of elderly in the population in most western countries, we studied injuries among the elderly (&gt;60 years) by investigating hospital-treated injuries in inpatients and outpatients, and fatal injuries. One-year Hospital Injury Data - Even though the elderly made up only 15% of the injured in one year, they accounted for 42% of the total cost of trauma medical care, showing that injuries among the elderly place a disproportional burden on the health care system. The mean medical care cost increased significantly from the age of 60 years. Serious injuries (MAIS&gt;3) in the elderly cost almost 2.5 times more than those in the younger group (&lt;60 years). Study of 1,313 injury events in 1,268 elderly showed annual injury, fracture, and mortality rates per 1,000 elderly population of 57, 31, and 0.6, respectively. Almost half were injured in the home environment, and 23% in the traffic environment. Most of the severe and critical injuries (MAIS&gt;4) occurred in the traffic environment. Injury rate, severity of injuries, fractures, and the duration of hospitalization increased with age. Almost half of the injuries were fractures; most common were wrist and hip fractures. Women had a higher injury rate, more severe injuries, and longer duration in hospitalization than men had. Study of 621 injury events in 600 elderly injured in the home environment, showed annual injury and fracture rates of 30 and 15 per 1,000 elderly home population, respectively. Injuries were grouped into fall injuries (76%) and non-fall injuries (24%). The fall injury incidence was higher in women than in men. Most falls occurred indoors. Environmental factors played a role in half of the fall injuries, and intrinsic factors in at least one fifth. Intrinsic factors in falls became increasingly important with advancing age. Non-fall injuries were mostly sustained in woodworking. Fall injuries were of a greater severity and accounted for 80% of the cost of medical care of elderly in the home environment. Study of 298 injury events in 297 elderly injured in the traffic environment, showed that pedestrian falls accounted for 52% of the injuries, and vehicle-related events for 44%. The main groups in the vehicle-related injury category were bicyclists (48%), car occupants (34%), and pedestrians (4%). Two thirds of the pedestrian falls involved slipping on ice/snow. Ice/snow-related injuries (all categories) accounted for 37% of the total cost of all injuries in the elderly in the traffic environment. Vehicle-related crashes resulted in the most severe and critical injuries and the most fatalities, and cost (total and mean) more than pedestrian falls. Fatal Injury Data from Northern Sweden - Study of 379 elderly injured in the traffic environment in a ten-year period, showed that the car occupants (43%) made up the largest category followed by pedestrians (28%), bicyclists (15%), and two-wheel-motor-vehicle riders (8%), but the risk of fatal injury per unit distance travelled was highest for pedestrians and bicyclists. Males had double the death rate as females. Most car occupants were killed in multivehicle crashes, mostly in the daylight, and at intersections. Ice/snow was the major (31%) precrash factor. One quarter of pedestrians were injured at pedestrian crossings, and half of them during darkness. One in six pedestrians was under the influence of alcohol. All pedestrians and bicyclists were injured in collisions with motor vehicles and most were injured at intersections. Pedestrians and bicyclists had more serious head injuries than chest injuries. Study of 514 car drivers (&gt;18 years) injured in a 13-year-period, showed that fatalities per unit distance, and per licensed driver were highest for the &gt;70-year-old and 18-19-year-old drivers. Elderly (&gt;60 year old) and &lt;25 year old drivers had similar fatality frequencies. The older drivers (&gt;60 years) initiated the crash more often than younger (&lt;60 years) ones. Fatal head injuries decreased whilst chest injuries increased with age. The older drivers were more likely to die from post-trauma complications than younger ones. In a study of role of disease in 480 fatally injured drivers (&gt;18 years) who died within three days of the crash, a grading system was developed to assess the probability of contribution of medical intrinsic factors (MIF) to the crash. Almost one quarter of the drivers were found to have MIF. Drivers with MIF were more often at fault than those without. Medical intrinsic factors were probably an underlying cause in 1 of 17 fatal crashes in all ages, and 1 of 5 fatal crashes in the elderly; in 4% of the elderly the probability was strong. A "passive automatic" approach which does not require any action on the part of the elderly, is to be recommended when improving safety in the home and in the traffic environments. The elderly drivers can be regarded as the "miner's canary" to indicate which passive safety improvements are needed in the traffic environment. In view of the expected population trends, it is important that authorities and public health workers accept the challenge to continue and intensify the injury preventive work for the elderly. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1994, härtill 7 uppsatser.</p> / digitalisering@umu

abstract: Walking and bicycling bring many merits to people, both physically and mentally. However, not everyone has an opportunity to enjoy healthy and safe bicycling and walking. Many studies suggested that access to healthy walking and bicycling is heavily related to socio-economic status. Low income population and racial minorities have poorer transportation that results in less walking and bicycling, as well as less access to public transportation. They are also under higher risks of being hit by vehicles while walking and bicycling. This research quantifies the relationship between socioeconomic factors and bicyclist and pedestrian involved traffic crash rates in order to establish an understanding of how equitable access to safe bicycling and walking is in Phoenix. The crash rates involving both bicyclists and pedestrians were categorized into two groups, minor crashes and severe crashes. Then, the OLS model was used to analyze minor and severe bicycle crash rates, and minor and severe pedestrian crash rates, respectively. There are four main results, (1) The median income of an area is always negatively related to the crash rates of bicyclists and pedestrians. The reason behind the negative correlation is that there is a very small proportion of people choosing to walk or ride bicycles as their commuting methods in the high-income areas. Consequently, there are low crash rates of pedestrians and bicyclists. (2) The minor bicycle crash rates are more related to socio-economic determinants than the severe crash rates. (3) A higher population density reduces both the minor and the severe crash rates of bicyclists and pedestrians in Phoenix. (4) A higher pedestrian commuting ratio does not reduce bicyclist and pedestrian crash rates in Phoenix. The findings from this study can provide a reference value for the government and other researchers and encourage better future decisions from policy makers. / Dissertation/Thesis / Masters Thesis Geography 2020

More than 900 bicyclists died in motor vehicle crashes in the United States in 2020, which represents a 50% increase from 2010 and the highest number of bicyclist deaths in nearly 35 years [1]. Reversing this trend will require efforts on multiple fronts, including reducing vehicle speeds and improving roadways and vehicles to be more hospitable to cyclists. Automatic emergency braking (ABB) with cyclist detection is a vehicle countermeasure with potential to prevent bicycle-motor vehicle crashes. AEB systems, which typically warn drivers of an impending collision and brake if drivers do not respond, have been shown to reduce vehicle-to-vehicle rear-end crash rates by 50% [2] and pedestrian crash rates by 27% [3]. Little is known about the real-world effects of ABB with cyclist detection on bicycle crashes. Subaru's EyeSight system, which includes ABB, has been capable of detecting cyclists in parallel configurations beginning in model year (MY) 2013 in the United States. The ability to detect cyclists in perpendicular configurations was added to some models beginning in MY 2022. The goal of this study is to evaluate the effects of the early version of EyeSight on U.S. bicycle crashes. [from Introduction]

It is an established fact that interaction of road users is crucial for road safety. However, the knowledge about what governs people’s behaviour in interaction with others and what these interactions mean is not well documented. The present study introduces a novel approach for traffic safety research and puts the cyclist identity at the centre of attention, in order to answer the questions how the heterogeneity of cyclists in terms of applied interaction strategies, opinions towards infrastructure and traffic safety can be explained. For this purpose, a qualitative study following the Grounded Theory methodology has been carried out. Fifteen in-depth-interviews with cyclists in Vienna were analysed in order to obtain data about these questions. As a result, we present a model sketch about constructing a cyclist identity, which serves as a framework that links different power relations in traffic, the switching perspectives of being a cyclist/car user and the changing conditions of cycling traffic policy through interaction strategies of self-portrayal, power demonstration and coping with fear. Finally, we argue that applying the often overlooked concept of ‘identity’ can bring new concepts into the debate on traffic safety for cyclists and support efficient traffic policy making.

As bicycle transportation has increased, especially among commuters, so have the types of bicycle infrastructure facilities increased. This report focuses on the application of several of these innovative bicycle infrastructure treatments in three different scenarios: shared-lane facilities, bicycle-specific facilities, and high-conflict area treatments. The focus treatments include the sharrow, Sharrow Bicycle Priority Lane, Green Bicycle Priority Lane, Bicycles May Use Full Lane sign, green bike lane, bike-box, green lane in a conflict area, and elephant's footprint markings. The goal of this report is to gather how well bicyclists understand their meaning, how they would use each, and which treatments are most preferred among bicyclists. Data for this study was gathered in the form of an online survey administered to 1000 bicyclists of varying levels and purposes from different regions of the country. The survey gathers general rider characteristics, asks how each bicyclist would use each treatment in different traffic speed and volume scenarios, and finally each respondent rates each of the treatments in order of preference. Using the survey results, the effectiveness of each treatment is analyzed in detail by different population segments of those surveyed. Bicyclist riding characteristics and route choice factors are also examined in detail to better understand the sampled population of riders. The results are discussed and conclusions to the effectiveness of each treatment are made.

Made available in DSpace on 2016-06-02T20:00:22Z (GMT). No. of bitstreams: 1 1652.pdf: 12006723 bytes, checksum: 1ba2e3c8b8896836f512f1ad710bfd56 (MD5) Previous issue date: 2007-10-30 / Financiadora de Estudos e Projetos / The spatial organization of Brazilian cities and the organization of their transportation systems have been causing an uneven accessibility distribution among other issues. This unbalance is marked by the fact that people who use private motorized modes of transportation are the ones that have been benefiting the most while the ones that use non motorized modes have been experiencing the worst conditions. The knowledge about the motorized transportation is much more developed than the knowledge regarding cycling as a mode of transportation. As long as this kind of unbalance remains there will not be equity in the society areas related to transportation. The purpose of this research is to provide general data and the fundamentals to permit the comprehension of the urban cycling transportation characteristics and the ways of organizing the cycling space as well. By evaluating different ways of organizing this space this dissertation presents the ones that had the best results or the ones that have the best potential to favourable results and that are also generic enough to be adequate to a great number of Brazilian localities. Within the chosen objectives the discussions and propositions presented in this dissertation are focused on introducing the bicyclists inside the road system so it would be possible to them to go everywhere in the cities under adequate conditions. Therefore the search was for discussions and propositions that took the bicyclists needs into consideration avoiding the ones that could exclude the bicyclists. This dissertation is focused on ways of organizing the cycling space that are suitable to new urbanization projects but specially on the ones that can fit to the areas with established road systems. This research allowed the verification that urban cycling transportation can really occur in a more harmonious way with the others modes of transportation. The presented and evaluated propositions indicate that cycling transportation is not incompatible with the motorized transportation / A organização espacial das cidades brasileiras e dos seus sistemas de transporte tem provocado, entre outros problemas, uma distribuição desigual da acessibilidade. Esse desequilíbrio é marcado pelo fato que os usuários dos modos motorizados particulares têm recebido os maiores benefícios, enquanto que os que se valem dos modos não motorizados são os mais prejudicados. As informações a respeito do uso da bicicleta como modo de transporte estão num estágio de desenvolvimento muito inferior ao das informações a respeito dos modos de transporte motorizado. Enquanto houver esse tipo de desequilíbrio, não haverá eqüidade nas áreas da sociedade que estejam relacionados aos transportes. O objetivo desta pesquisa é fornecer dados gerais e fundamentos para compreensão das características do transporte cicloviário urbano, assim como das formas de organizar o espaço de circulação da bicicleta. Busca-se, através da avaliação de variadas formas de organizar esse espaço, expor as que apresentaram melhores resultados ou melhores potenciais de resultados favoráveis e que tenham características gerais o suficiente para se adequarem a um grande número de localidades urbanas brasileiras. Dentro dos objetivos traçados, as discussões e propostas apresentadas nesta dissertação foram focadas na inserção do condutor de bicicleta dentro da estrutura viária, de modo que lhe seja possível alcançar todos os lugares das cidades, em condições adequadas. Dessa forma, buscou-se a apresentação de discussões e propostas que lidassem com as necessidades dos condutores de bicicleta, evitando as que pudessem resultar na exclusão destes. Foi dado, portanto, um enfoque às formas de organização do espaço de circulação da bicicleta que fossem adequados a projetos de novas urbanizações, mas principalmente que buscassem atender às características de áreas urbanas com sistemas viários estabelecidos. Essa pesquisa permitiu a verificação de que o transporte cicloviário urbano pode realmente ocorrer de forma mais harmoniosa com os demais modos de transporte. As propostas avaliadas e apresentadas indicam que o transporte cicloviário não é incompatível com o transporte motorizado

The diploma thesis deals with the transfer of cyclists through the dam of Nové Mlýny. The design runs alongside the dam, outside the existing I/52 road, as a preparation for the D52 motorway. The thesis solves the design of longitudinal alignment and vertical alignment of the cycle path along the I/52 road, connection of the cycle path to the adjacent network of cycling routes and variants of crossing cycle path 5174 with route I/52 due to an increase of safety.

Most of the existing bicycle flow traffic research is limited to characterizing the longitudinal motion of bicyclists based on the assumption that there is no significant differences between the dynamics of a single-file bicycle traffic and the longitudinal motion behavior of cars. This research reparametrizes an existing car-following model to describe bicycle-following and motion behavior. Furthermore, the lack of naturalistic data has limited the validation of this model. This research aims at developing a descriptive model that is capable of capturing the inherent non-lane-based traffic behavior characteristics of bicycle traffic and provides a methodology for extracting naturalistic cycling data from video feeds for use in safety and mobility applications. In this study, The Fadhloun-Rakha (FR) bicycle-following longitudinal motion model was extended through complementing it with a lateral motion strategy; thus allowing for overtaking maneuvers and lateral bicycle movements. For the most part, the following strategy of the FR model remains valid for modeling the longitudinal motion of bicycles except for the activation conditions of the collision avoidance strategy which are modified in order to allow for overtaking when possible. The proposed methodology is innovative in that it makes use of the intersection of certain pre-defined regions around the bicycles to decide on the feasibility of angular motion along with its direction and magnitude. The resulting model is the first point-mass dynamics-based model for the description of the longitudinal and lateral behavior of bicycles in both constrained and unconstrained conditions, and it is the only existing model that is sensitive to the bicyclist physical characteristics and the bicycle and roadway surface conditions given that the used longitudinal logic was previously validated against experimental cycling data. In relation to the development of the naturalistic cycling dataset, the used videos come from a dataset collected in a previous Virginia Tech Transportation Institute study in collaboration with SPIN in which continuous video data at a non-signalized intersection on the Virginia Tech campus was recorded. The research applied computer vision and machine learning techniques to develop a comprehensive framework for the extraction of naturalistic cycling trajectories. In total, this study resulted in the collection and classification of 619 bicycle trajectories based on their type of interactions with other road users. The results confirm the success of the proposed methodology in relation to extracting the locations, speeds, and accelerations of the bicycles with a high precision level. Furthermore, preliminary insights into the acceleration and speed behavior of bicyclists around motorists are determined. / Master of Science / The behavior of bicycle traffic differs from the that of cars. Bicycle traffic flow dynamics is unconstrained in lateral motion and overtaking when compared to car traffic flow. Based on this inherent behavior, existing car-following can only model the longitudinal motion of the bicycle flow traffic and it does not describe the non-lane base traffic that characterizes bicycle traffic dynamics. Furthermore, the existing experimental controlled dataset used for validating bicycle traffic flow models does not capture the naturalistic behavior of cyclists. Therefore, this research aims to develop a descriptive model that is capable of capturing the inherent non-lane-based traffic behavior characteristics of bicycle traffic and provides a methodology for extracting a naturalistic cycling data from a video dataset for use in safety and mobility applications. In this study, the Fadhloun-Rakha (FR) bicycle-following longitudinal motion model was extended through complementing it with a lateral motion strategy; thus allowing for overtaking maneuvers and lateral bicycle movements. For the most part, the following strategy of the FR model remains valid for modeling the longitudinal motion of bicycles except for the activation conditions of the collision avoidance strategy which are modified in order to allow for overtaking when possible. The proposed methodology is innovative in that it makes use of the intersection of certain pre-defined regions around the bicycles to decide on the feasibility of angular motion along with its direction and magnitude. The resulting model is the first point-mass dynamics-based model for the description of the longitudinal and lateral behavior of bicycles in both constrained and unconstrained conditions, and it is the only existing model that is sensitive to the bicyclist physical characteristics and the bicycle and roadway surface conditions given that the used longitudinal logic was previously validated against experimental cycling data. In relation to the development of the naturalistic cycling dataset, the used videos come from a dataset collected in a previous Virginia Tech Transportation Institute study in collaboration with SPIN in which continuous video data at a non-signalized intersection on the Virginia Tech campus was recorded. The research applied computer vision and machine learning techniques to develop a comprehensive framework for the extraction of naturalistic cycling trajectories. In total, this study resulted in the collection and classification of 619 bicycle trajectories based on their type of interactions with other road users. The results confirm the success of the proposed methodology in relation to extracting the locations, speeds, and accelerations of the bicycles with a high precision level. Furthermore, preliminary insights into the acceleration and speed behavior of bicyclists around motorists are determined.