Massie, Blower, and Campbell (1997) indicate that trucks that operate less than 50 miles from the vehicle's home base comprise 58% of the trucking industry. However, despite being the largest segment, research involving local/short haul (L/SH) operations has been scant. In fact, little is known about the general safety issues in L/SH operations. As a precursor to the present research, Hanowski, Wierwille, Gellatly, Early, and Dingus (1998) conducted a series of focus groups in which L/SH drivers provided their perspective on safety issues, including fatigue, in their industry. As a follow-up to the Hanowski et al. work, the effort presented here consisted of an on-road field study where L/SH trucks were instrumented with data collection equipment. Two L/SH trucking companies and 42 L/SH drivers participated in this research. To the author's knowledge, this is the first in-situ data collection effort of its kind with L/SH drivers. The analyses focused on determining if fatigue is an issue in L/SH operations. Of primary interest were critical incidents (near-crashes) where drivers were judged to be at fault. The results of the analyses indicated that fatigue was present immediately prior to driver involvement in at-fault critical incidents. Though it is difficult to determine why fatigue was present, the results seem to indicate that much of the fatigue that the drivers' experienced was brought with them to the job, rather than being caused by the job. There are four basic outputs of the Phase II research: (1) a description of the L/SH drivers who participated, (2) a description of critical incidents, (3) a determination if fatigue is an issue in L/SH trucking, and (4) the validation of the fatigue factors cited in Hanowski et al. (1998) using a proposed fatigue model. These four outputs culminate in a set of pragmatic guidelines to address fatigue and other safety issues in L/SH operations. Five guidelines are proposed that are directed at: (1) driver education with regard to on-the-job drowsiness/inattention, (2) driver education with regard to sleep hygiene, (3) driver training, particularly for novice L/SH truck drivers, (4) driver screening, and (5) public monitoring of L/SH driver performance. / Ph. D.

O objetivo deste trabalho é analisar a influência dos veículos pesados na capacidade de rodovias de pista simples e mão dupla de direção através da determinação de fatores de equivalência veicular para diversos comprimentos e magnitudes de aclives. A presença de veículos de grande porte em rodovias de pista simples contribui para a redução dos níveis de serviço devido ao seu tamanho e desempenho. Um caminhão ocupa mais espaço na via que um automóvel, em função de seu maior comprimento, reduzindo a capacidade da via. Numa rodovia de pista simples, os automóveis devem ultrapassar os veículos pesado; caso a ultrapassagem não seja possível, ocorre a formação de pelotões, que ocasionam uma degradação no nível de serviço. O método proposto determina os fatores de equivalência a partir das velocidades médias dos veículos ao longo dos aclives e das oportunidades de ultrapassagem. Para o cálculo dos headways na corrente oposta necessários para uma ultrapassagem, este trabalho propõe um novo modelo cinemático de ultrapassagem. Os fatores de equivalência são calculados para diversas categorias veiculares; um conjunto de tabelas determinadas a partir da composição de tráfego observada é também apresentado. O efeito da sobrecarga na capacidade é estudado para a categoria de caminhões mais comum, os caminhões semi-pesados. / This study assesses the impacts of heavy vehicles on the capacity of two-lane highways through equivalency factors determined for various grade lengths and magnitudes. Heavy vehicles impact negatively the capacity of two-lane highways due to their size and performance. As a truck is longer than a car, it reduces the capacity of the road due to its length. Given that trucks have poorer performances than cars, in a two-lane road, cars generally pass trucks, and platoons are formed when passing opportunities are scarce. The formation of platoons cause a noticeable reduction on the level of service. The proposed method calculates equivalency factors from the averaqe speeds on grades and from the passing opportunities. A new cinematic model for the passing maneuver that is able to determine the required headways in the opposite flow for a safe passing maneuver is proposed. The equivalency factors are determined for a set of pre-defined vehicular classes; a set of truck equivalents is also calculated for the observed traffic mix. The effect of overloading on capacity is analized for the most common truck type.

O objetivo deste trabalho é analisar a influência dos veículos pesados na capacidade de rodovias de pista simples e mão dupla de direção através da determinação de fatores de equivalência veicular para diversos comprimentos e magnitudes de aclives. A presença de veículos de grande porte em rodovias de pista simples contribui para a redução dos níveis de serviço devido ao seu tamanho e desempenho. Um caminhão ocupa mais espaço na via que um automóvel, em função de seu maior comprimento, reduzindo a capacidade da via. Numa rodovia de pista simples, os automóveis devem ultrapassar os veículos pesado; caso a ultrapassagem não seja possível, ocorre a formação de pelotões, que ocasionam uma degradação no nível de serviço. O método proposto determina os fatores de equivalência a partir das velocidades médias dos veículos ao longo dos aclives e das oportunidades de ultrapassagem. Para o cálculo dos headways na corrente oposta necessários para uma ultrapassagem, este trabalho propõe um novo modelo cinemático de ultrapassagem. Os fatores de equivalência são calculados para diversas categorias veiculares; um conjunto de tabelas determinadas a partir da composição de tráfego observada é também apresentado. O efeito da sobrecarga na capacidade é estudado para a categoria de caminhões mais comum, os caminhões semi-pesados. / This study assesses the impacts of heavy vehicles on the capacity of two-lane highways through equivalency factors determined for various grade lengths and magnitudes. Heavy vehicles impact negatively the capacity of two-lane highways due to their size and performance. As a truck is longer than a car, it reduces the capacity of the road due to its length. Given that trucks have poorer performances than cars, in a two-lane road, cars generally pass trucks, and platoons are formed when passing opportunities are scarce. The formation of platoons cause a noticeable reduction on the level of service. The proposed method calculates equivalency factors from the averaqe speeds on grades and from the passing opportunities. A new cinematic model for the passing maneuver that is able to determine the required headways in the opposite flow for a safe passing maneuver is proposed. The equivalency factors are determined for a set of pre-defined vehicular classes; a set of truck equivalents is also calculated for the observed traffic mix. The effect of overloading on capacity is analized for the most common truck type.

<p>The ambition to lower fuel consumption has been a goal for the vehicle industrysince many years.  During the first oil crisis in the seventies this first came intolight and it has become more relevant during the last years climate change debate.Fuel costs are also an issue.  Reducing lifetime costs, in which fuel is 30 %, givesa competitive advantage to the vehicle producer.  Over the years the drive trainhas been made efficient to the point where a reduction in fuel consumption due toimprovements in the drive train is highly expensive to develop.  The fact that thedriver behavior is a big factor in the vehicle’s fuel consumption has recently comeinto attention.  This master thesis has been performed at Scania in Södertälje andpresents a way to give the driver advice in advance of difficult road segments.  Theadvice will help the driver drive in a fuel efficient manner. Focus is put on a specificcase where the vehicle approaches a downhill and advice is given for the driver tolet the vehicle coast up to the start of the downhill so that the vehicle can regainits speed in the downhill.  The detection of the downhill is made with look-aheadtechnology where a GPS and a digital 3D road map makes the topography of theroad segment ahead available.</p>

The ambition to lower fuel consumption has been a goal for the vehicle industrysince many years.  During the first oil crisis in the seventies this first came intolight and it has become more relevant during the last years climate change debate.Fuel costs are also an issue.  Reducing lifetime costs, in which fuel is 30 %, givesa competitive advantage to the vehicle producer.  Over the years the drive trainhas been made efficient to the point where a reduction in fuel consumption due toimprovements in the drive train is highly expensive to develop.  The fact that thedriver behavior is a big factor in the vehicle’s fuel consumption has recently comeinto attention.  This master thesis has been performed at Scania in Södertälje andpresents a way to give the driver advice in advance of difficult road segments.  Theadvice will help the driver drive in a fuel efficient manner. Focus is put on a specificcase where the vehicle approaches a downhill and advice is given for the driver tolet the vehicle coast up to the start of the downhill so that the vehicle can regainits speed in the downhill.  The detection of the downhill is made with look-aheadtechnology where a GPS and a digital 3D road map makes the topography of theroad segment ahead available.

Este trabalho traz um estudo de veículos rodoviários articulados pesados durante o processo de freagem incluindo uma revisão bibliográfica sobre aspectos humanos, ambientais, legais, veiculares e operacionais relacionados com o desempenho, a estabilidade e a segurança veicular e uma descrição da técnica dos mapas de desempenho. Tal técnica é original e inovadora e foi desenvolvida através de modelo matemático e respectivo programa computacional para analisar o desempenho e a estabilidade de veículo-trator-semi-reboque durante a freagem em trecho retilíneo. Com esta técnica é possível obter o desempenho e a estabilidade direcional de veículos articulados pesados na freagem, obedecendo as restrições geométricas do veículo-trator-semi-reboque e de peso estabelecidas pelo fabricante e pela legislação, para todas as condições de carregamento e qualquer condição operacional. Os resultados teórico-experimentais que validaram o modelo matemático adotado também são mostrados neste trabalho. Este trabalho foi desenvolvido com o apolo da Mercedes-Benz do Brasil, resultando numa integração entre Empresa e Universidade que trouxe uma contribuição efetiva para o uso do veículo-trator-semi-reboque com maior eficiência, e segurança, unindo esforços da Empresa e da Universidade em prol da segurança veicular e do desenvolvimento tecnológico do Brasil. / This work describes a study of articulated heavy vehicles during braking process including the state-of-the-art of human, environmental, legal, vehicular and operational aspects related with performance, stability and vehicular safety and a description of performance charts technique. This technique is original and innovative and was developed with mathematical model and related computer program to analize the tractor-semi-trailer performance and stability during the braking process in a straight line path. With this technique is possible to obtain the performance and directional stability of articulated heavy vehicles during braking process, obeying the geometrical restrictions of the tractor-semi-trailer and the legal and maker\'s weight restrictions, for all states of loading and any operational conditions. The theoretical-experimental results that validated the mathematical model adopted are also shown in this work. This work was developed with the support of Mercedes-Benz of Brazil, resulting in a Company and University integration that brought an effective contribution for the more efficient and safe use of tractor-semi-trailer, enlarging the Company and University efforts to the benefit of vehicular safety and technological development in Brazil.

Multi-trailer articulated heavy vehicles (MTAHVs) exhibit unstable motion modes at high speeds, including jack-knifing, trailer swing, and roll-over. These unstable motion modes may lead to fatal accidents. On the other hand, these vehicle combinations have poor maneuverability at low speeds. Of all contradictory design criteria of MTAHVs, the trade-off relationship between the maneuverability at low speeds and the lateral stability at high speeds is the most important and fundamental. This trade-off relationship has not been adequately addressed. The goal of this research is to address this trade-off relationship through the design optimization of MTAHVs with active safety systems. A parallel design optimization (PDO) method is developed and applied to the design of MTAHVs with integrated active safety systems, which involve active trailer steering (ATS) control, anti-roll (AR) control, differential braking (BD) control, and a variety of combinations of these three control strategies. To derive model-based controllers, a single-trailer articulated heavy vehicle (STAHV) model with 5 degrees of freedom (DOF) and a MTAHV model with 7 DOF are generated. The vehicle models are validated with those derived using a commercial software package, TruckSim, in order to examine their applicability for the design optimization of MTAHVs with active safety systems. The PDO method is implemented to perform the concurrent design of the plant (vehicle model) and controllers. To simulate the closed-loop testing maneuvers, a driver model is developed and it is used to drive the virtual vehicle following the prescribed path. Case studies indicate that the PDO method is effective for identifying desired design variables and predicting performance envelopes in the early design stages of MTAHVs with active safety systems. / UOIT

Este trabalho traz um estudo de veículos rodoviários articulados pesados durante o processo de freagem incluindo uma revisão bibliográfica sobre aspectos humanos, ambientais, legais, veiculares e operacionais relacionados com o desempenho, a estabilidade e a segurança veicular e uma descrição da técnica dos mapas de desempenho. Tal técnica é original e inovadora e foi desenvolvida através de modelo matemático e respectivo programa computacional para analisar o desempenho e a estabilidade de veículo-trator-semi-reboque durante a freagem em trecho retilíneo. Com esta técnica é possível obter o desempenho e a estabilidade direcional de veículos articulados pesados na freagem, obedecendo as restrições geométricas do veículo-trator-semi-reboque e de peso estabelecidas pelo fabricante e pela legislação, para todas as condições de carregamento e qualquer condição operacional. Os resultados teórico-experimentais que validaram o modelo matemático adotado também são mostrados neste trabalho. Este trabalho foi desenvolvido com o apolo da Mercedes-Benz do Brasil, resultando numa integração entre Empresa e Universidade que trouxe uma contribuição efetiva para o uso do veículo-trator-semi-reboque com maior eficiência, e segurança, unindo esforços da Empresa e da Universidade em prol da segurança veicular e do desenvolvimento tecnológico do Brasil. / This work describes a study of articulated heavy vehicles during braking process including the state-of-the-art of human, environmental, legal, vehicular and operational aspects related with performance, stability and vehicular safety and a description of performance charts technique. This technique is original and innovative and was developed with mathematical model and related computer program to analize the tractor-semi-trailer performance and stability during the braking process in a straight line path. With this technique is possible to obtain the performance and directional stability of articulated heavy vehicles during braking process, obeying the geometrical restrictions of the tractor-semi-trailer and the legal and maker\'s weight restrictions, for all states of loading and any operational conditions. The theoretical-experimental results that validated the mathematical model adopted are also shown in this work. This work was developed with the support of Mercedes-Benz of Brazil, resulting in a Company and University integration that brought an effective contribution for the more efficient and safe use of tractor-semi-trailer, enlarging the Company and University efforts to the benefit of vehicular safety and technological development in Brazil.

Background. Over the years, between 2013 and 2017, accidents between HeavyGoods Vehicles and Pedestrians have come to increase. Leading causes stem frominattentiveness and lack of communication between driver and pedestrians. Withthe advent of Autonomous vehicles, set to be able to reduce accidents, uncertainties in how communication and trust between humans and machines will be formed re-mains. Objectives. The research aim has been to understand the difficulties and problemssurrounding heavy vehicles, and the problems that today’s heavy vehicle operators faces, from which a technical solution that addressees the uncovered needs, is devel-oped. Methods. Design Research Methodology and MSPI Innovation Process has beenused in combination for acquiring and validating information around the problem.Shadowing sessions, unstructured interviews has been used for acquiring information.Literature reviews have been done to find academic validation in hypotheses statedthroughout the research. From the information gathered, iterative prototypes havebeen built. Results. From the needfinding that was conducted, safety around trucks was thefield on which the scope of the research was focused around. Due the larger size oftruck, decision-making through eye contact and intention determining is set to beharder when dealing with heavy vehicles, leading to an uncertainty around heavyvehicles residing with pedestrians in how to act around these. With the operatorsof these vehicles finding the unpredictable nature of pedestrians and cyclist in trafficto be troublesome and safety imposing, the research aim was set around addressing these needs. A communication console was developed, that is able to communi-cate safety-critical information between heavy vehicle operators and vulnerable road users, as means of reducing front collisions between said parts. Conclusions. The console has been developed through iterative prototyping andtesting, with design requirements being acquired through learnings and feedbackgathered from each iteration. The resulting communication console being presentedis able to share critical information being sought by pedestrians for decision-making,primarily that of eye contact and intentions of oncoming vehicles. The system servesas a proof of concept, that could through extensive traffic safety testing, help reducefront collisions between Heavy Goods Vehicles and Vulnerable Road Users, as well as, through further development, become the central communication console for au-tonomous vehicles to ensure partnership and intuitive communication between these and the surroundings.

El presente plan consiste en importar y comercializar EcoBlue (urea líquida automotriz), esta es necesaria en vehículos pesados con sistema SCR (selective catalytic reduction) con objeto de reducir la emisión de gases contaminantes de motores diésel cumpliendo así el decreto supremo N°010-2017-MINAM (los vehículos importados desde abril 2018 deben cumplir con la norma Euro IV). Nuestro mercado potencial son las empresas que cuentan con vehículos pesados (sistema SCR), el cual creció 77% en el 2019 respecto al año anterior, en el 2020 se redujo en 25% por el COVID-19 y en el primer trimestre del 2021 se refleja una recuperación del 42% respecto al primer trimestre del 2020. Nuestro mercado objetivo son empresas no corporativas (hasta diez unidades) con sede en Lima o Callao (9,650 vehículos), estas empresas están desatendidas por proveedores enfocados en empresas corporativas o cuyo core de negocio no es la venta de urea (concesionario). Nuestra declaración de posicionamiento: “Para empresas no corporativas que cuentan con vehículos pesados con el sistema SCR, EcoBlue es la mejor opción en venta de urea líquida automotriz que ofrece el mejor servicio porque estamos pendientes de las necesidades del cliente y realizamos despacho a domicilio”, asociado a nuestra propuesta de valor. En la simulación con proyección a cinco años, obtenemos un valor actual neto de S/256,524 del flujo de caja libre (inversión 100% de capital propio), además la tasa interna de retorno resulta 43% (mayor a la tasa de descuento), luego ambos indicadores muestran que sí es viable nuestro plan. / This plan consists of importing and commercializing EcoBlue (automotive urea), this is necessary in heavy vehicles with SCR (selective catalytic reduction) system in order to reduce the emission of polluting gases from diesel engines, thus complying with supreme decree No. 010- 2017-MINAM (vehicles imported from April 2018 must comply with the Euro IV standard). Our potential market is companies that have heavy vehicles (SCR system), which grew 77% in 2019 compared to the previous year, in 2020 it decreased by 25% due to COVID-19 and in the first quarter of 2021 reflects a 42% recovery compared to the first quarter of 2020. Our target market is non-corporate companies (up to ten units) based in Lima or Callao (9,650 vehicles), these companies are neglected by suppliers focused on corporate companies or whose core business is not the sale of urea (concessionaire). Our positioning statement: "For non-corporate companies that have heavy vehicles with the SCR system, EcoBlue is the best option for the sale of automotive urea that offers the best service because we are aware of the customer's needs and carry out home delivery" , associated with our value proposition. In the simulation with a five-year projection, we obtain a net present value of S / 256,524 of the free cash flow (100% equity investment), in addition the internal rate of return is 43% (greater than the discount rate), then both indicators show that our plan is viable. / Trabajo de investigación