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Kontrola bezpečnostního mechanismu přípojných vozidel / Analysis the safety mechanism of the trailersPantůček, Michal January 2019 (has links)
This diploma thesis is engaged in the analysis of a safety mechanism, which is a part of a truck trailer. This mechanism provides a safe and firm connection of a container to the trailer. Primarily abroll containers according to German standard DIN 30 722 are being transported. The introductory part of the thesis deals with the current traffic condition and the accident rate in the Czech Republic. Legislative requirements for safety elements of trailer technology for road transportation are further defined. They are followed by a recherche of industrial solutions for securing mechanisms. Consequently calculations to obtain necessary securing force were performed. An analysis of the mechanism kinematics was carried out then. A structural check of selected mechanism elements was carried out following the kinematics check. Further, an optimalization of a transom design was carried out followed by another structural check. The structural checks were carried out using both the analytical method and the finite element method. In conclusion design documentation was elaborated. This diploma thesis was elaborated in cooperation with the SVAN Chrudim s.r.o.
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Zajišťovací mechanismus kontejneru / Safety container mechanismKubín, Martin January 2008 (has links)
This diploma thesis is focused on container safety mechanism which is a part of truck trailers. It designs pneumatic – mechanical safety mechanism suitable for safe transport of container with driving drum which are produced according to German standard DIN 30 722. It concerns containers with total weight of 22 tons. The first part of this thesis is focused on evaluation of possible load by common operating conditions. The technique of mechanism design is introdiced in several developing stages from original solution to final version. The final version processes all force and kinetic aspects. Selected parts of safety mechanism are controlled from solidity perspective. Some calculations and analysis were processed both by convention method and method of final elements on PC. Thesis was created in close cooperation with company SVAN Chrudim, s.r.o.
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Rám přívěsu Variant 350 pro přepravu kabelových cívek / Trailer frame VARIANT 350 for transport cabel spoolsWeingärtner, Jan January 2011 (has links)
This diploma thesis deals with the solution of the trailer frame Variant 350 for transport of cable reels. The aim of this work is to drive a dynamic simulation of a cable lift generated by the track and in specific places to find this track burdensome conditions that affect the design of the frame. According to these states gained strenght to control the finite element method, implement and then modify the design and then create construction drawings prepared.
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Analýza jízdy osobního vozidla s přívěsem / Analysis of Driving a Passenger Vehicle with a TrailerŠujan, Tomáš January 2013 (has links)
The subject of this thesis is the analysis of the negative effects associated with the operation of a trailer for a personal vehicle with respect to the design speed, technical checks and analysis related legislation. Its work is drawn from the measurement, cooperation with leading Czech production plant trailers Vezeko s.r.o., an organization engaged in the implementation of engineering controls DEKRA Automobil a.s. and available literature, including electronic resources. Results of the work end with proposals for specific measures to minimize the identified adverse effects.
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Path follower for reversing off-axle single-joint semitrailer trucksCerna Herrera, Fernando Javier January 2021 (has links)
Semitrailer trucks are widely used for transportation of goods in Sweden and around the world. Given their usefulness, and since they require specialized drivers, there is an increased need to automate the operation of these vehicles. In particular, reversing these vehicles is considered a challenging maneuver, mainly because of the jackknifing effect. To tackle this challenge, this thesis investigates path following for reversing single-joint semitrailer trucks, by comparing two path-following controllers, corresponding to a Linear Quadratic Regulator (LQR) and a Model Predictive Control (MPC), respectively. Both controllers receive kinematically feasible reference trajectories from a path planner (which is part of another thesis work), which makes it possible to avoid jackknifing as long as the reference joint angle between the trailer and the truck is closely followed. Moreover, they use a linearized and discretized 1-trailer kinematic model, defined in terms of the reference tracking errors for the truck as states. To evaluate the performance of the controllers, a Python simulation is implemented using the 1-trailer kinematic model. Using this simulation, the controllers are compared using metrics related to the reference tracking errors along the generated path and the controller execution time. The results show that the LQR and the MPC controllers perform similarly for most cases. Even though there are certain cases where the MPC outperforms the LQR, the execution time of the MPC is at least one order of magnitude slower, which makes the LQR an attractive solution for practical implementations, as long as certain assumptions (small initial deviations, reliable measurements) are ensured. As such, an LQR controller might be preferred by the industry because, while the performance from both controllers is similar, it can be considered a more efficient controller. / Lastbilar med olika släpvagnskombinationer används ofta för godstransporter i Sverige och runt om i världen. Med tanke på deras användbarhet och eftersom de kräver specialiserade förare finns det ett ökat behov av att automatisera driften av dessa fordon. I synnerhet anses backning av dessa fordon vara en utmanande manöver, främst på grund av jackknifseffekten. För att lösa detta problem undersöker denna rapport vägföljande för backande lastbilar med släp genom att jämföra två olika vägföljande styrenheter: Linear Quadtratic Regulator (LQR) och Model Predictive Control (MPC). Båda styrenheterna får kinematiskt genomförbara referensbanor från en vägplanerare (som är en del av en annan uppsats), vilket gör det möjligt att undvika jackknipning så länge referensvinkeln mellan släpet och lastbilen följs noggrant. Dessutom använder de en linjäriserad och diskretiserad kinematisk modell med en lastbil, definierad i termer av lastbilens referensspårningsfel som tillstånd. För att utvärdera kontrollernas prestanda implementeras en Python-simulering med den kinematisk modell med en lastbil. Med denna simulering jämförs de två styrenheterna med mått relaterade till referensspårningsfelen längs den generarade vägen och styrenheternas exekveringstid. Resultaten visar att LQR och MPCpresterar likadant i de flesta fallen. Även om det finns vissa fall där MPC överträffar LQR, är exekveringstiden för MPC åtminstone en storleksordning långsammare, vilket gör LQR till en attraktiv lösning för praktiska implementeringar, så länge som vissa antaganden (små initiala avvikelser, pålitliga mått) säkerställs. Som sådan kan en LQR-styrenhet föredras av industrin, för även om prestandan från båda styrenheterna är lika, kan den betraktas som en enklare styrenhet.
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Hotspot Detection for Automatic Podcast Trailer Generation / Hotspot-detektering för automatisk generering av podcast-trailersZhu, Winstead Xingran January 2021 (has links)
With podcasts being a fast growing audio-only form of media, an effective way of promoting different podcast shows becomes more and more vital to all the stakeholders concerned, including the podcast creators, the podcast streaming platforms, and the podcast listeners. This thesis investigates the relatively little studied topic of automatic podcast trailer generation, with the purpose of en- hancing the overall visibility and publicity of different podcast contents and gen- erating more user engagement in podcast listening. This thesis takes a hotspot- based approach, by specifically defining the vague concept of “hotspot” and designing different appropriate methods for hotspot detection. Different meth- ods are analyzed and compared, and the best methods are selected. The selected methods are then used to construct an automatic podcast trailer generation sys- tem, which consists of four major components and one schema to coordinate the components. The system can take a random podcast episode audio as input and generate an around 1 minute long trailer for it. This thesis also proposes two human-based podcast trailer evaluation approaches, and the evaluation results show that the proposed system outperforms the baseline with a large margin and achieves promising results in terms of both aesthetics and functionality.
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Line-of-Sight Guidance for Wheeled Ground VehiclesLin, Letian 23 September 2020 (has links)
No description available.
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Heavy Truck Modeling and Estimation for Vehicle-to-Vehicle Collision Avoidance SystemsWolfe, Sage M. 20 October 2014 (has links)
No description available.
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Viabilidade de operação do duplo semi-reboque de cinco eixos no Brasil / Operation feasibility of the five axle twin trailer truck in BrazilReis, Neuto Gonçalves dos 22 April 1996 (has links)
Este trabalho investiga a viabilidade de se implantar no Brasil o veículo combinado de cinco eixos constituído de um cavalo mecânico mais dois semi-reboques acoplados por um dolly intermediário e chamado aqui de Duplo Semi-Reboque (DSR). Essa investigação inclui tanto aspectos econômicos (custos operacionais) quanto operacionais (densidade das cargas, rotas, demandas, veículos utilizados), tecnológicos (veículos e implementes), legais (pesos e dimensões), de segurança (estabilidade, dirigibilidade, risco de acidentes e impacto sobre o tráfego de outros veículos) e de inter-relação com a infra-estrutura rodoviária. Como a configuração analisada é largamente utilizada nos Estados Unidos, com o nome de twin trailer truck, faz-se uma ampla revisão da literatura norte-americana. O estudo apresenta as características técnicas do twin, levanta a legislação norte-americana de carga por eixo e mostra como a busca de produtividade e o aumento da carga volumosa conduziram à necessidade de veículos mais longos. Compila artigos sobre a estabilidade, a dirigibilidade e o impacto sobre o tráfego dos veículos longos combinados. Sintetiza pesquisas comparando taxas de acidentes dos veículos combinados com os caminhões convencionais. A maioria desses estudos conduz à conclusão de que, embora os twins possam degradar ligeiramente as condições de segurança de tráfego e aumentar o desgaste elos pavimentos, essa degradação é compensada pela redução do número de viagens e do custo do transporte. Conclui-se que o veículo seria economicamente viável no Brasil para substituir caminhões trucados em rotas de demanda limitada, e que poderia também economizar custos na substituição a veículos convencionais no transporte de cargas volumosas, sem provocar maiores impactos sobre a segurança operacional. Pesquisa com frotistas mostra que quase 50% das transportadoras de carga fracionada operam cargas de densidade compatível com o DSR. A introdução do veículo, no entanto, enfrenta fortes obstáculos legais e exigiria mudança profunda na legislação dos veículos combinados longos. / This paper investigates the feasibility of introducing the American twin trailer truck in the Brazilian road transport network. The twin is a five axle configuration with one tractor and two semi-trailers, coupled by an intermediate dolly. The investigation embraces not only economic questions (operational costs), but also operational aspects (freight density and volume, vehicle choice, line extension etc), technological questions (vehicles, trailers and dollies), weights and dimensions legislation, safety impacts (handling and stability, impact of traffic operations and statistic studies of accident rates) and the twin\'s interface with the highway facilities. The American and Canadian studies about twins are reviewed. The paper presents the technical characteristics of twins, the american weights and dimensions legislation and shows how the claim for more productivity in the transport industry and the low density freight growth have induced the use of longer combinations. The study compiles the main results presented in the literature about handling, stability and the twin trailer impact on the highway traffic and analyzes statistics comparing doubles with semi-trailer accident rates. The literature review leads to the conclusion that, althrough the twins could degrade slightly the vehicle traffic safety performance and accelerate the pavement wear, this degradation is overwhelmed by the reduction of the number of vehicles on the roads and direct and indirect transportation costs. The introduction of the win trailer truck in Brazil could be advantageous in order to replace tandem trucks on low demand routes. The savings in terminal times and the higher capacitiy of this configuration would cut costs as compared to the straight truck, semi-trailer and truck-and-trailer configurations, without relevant deterioration of the operational safety. The results of a large sample with brazilian LTL companies show that almost 50% of them operate with a freight density that would be ideal for twins. The twin\'s introduction, however, faces strong legal impediments in some markets, and only would be feasible if deep changes in the Brazilian weight and dimension regulations would be undertaken.
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Viabilidade de operação do duplo semi-reboque de cinco eixos no Brasil / Operation feasibility of the five axle twin trailer truck in BrazilNeuto Gonçalves dos Reis 22 April 1996 (has links)
Este trabalho investiga a viabilidade de se implantar no Brasil o veículo combinado de cinco eixos constituído de um cavalo mecânico mais dois semi-reboques acoplados por um dolly intermediário e chamado aqui de Duplo Semi-Reboque (DSR). Essa investigação inclui tanto aspectos econômicos (custos operacionais) quanto operacionais (densidade das cargas, rotas, demandas, veículos utilizados), tecnológicos (veículos e implementes), legais (pesos e dimensões), de segurança (estabilidade, dirigibilidade, risco de acidentes e impacto sobre o tráfego de outros veículos) e de inter-relação com a infra-estrutura rodoviária. Como a configuração analisada é largamente utilizada nos Estados Unidos, com o nome de twin trailer truck, faz-se uma ampla revisão da literatura norte-americana. O estudo apresenta as características técnicas do twin, levanta a legislação norte-americana de carga por eixo e mostra como a busca de produtividade e o aumento da carga volumosa conduziram à necessidade de veículos mais longos. Compila artigos sobre a estabilidade, a dirigibilidade e o impacto sobre o tráfego dos veículos longos combinados. Sintetiza pesquisas comparando taxas de acidentes dos veículos combinados com os caminhões convencionais. A maioria desses estudos conduz à conclusão de que, embora os twins possam degradar ligeiramente as condições de segurança de tráfego e aumentar o desgaste elos pavimentos, essa degradação é compensada pela redução do número de viagens e do custo do transporte. Conclui-se que o veículo seria economicamente viável no Brasil para substituir caminhões trucados em rotas de demanda limitada, e que poderia também economizar custos na substituição a veículos convencionais no transporte de cargas volumosas, sem provocar maiores impactos sobre a segurança operacional. Pesquisa com frotistas mostra que quase 50% das transportadoras de carga fracionada operam cargas de densidade compatível com o DSR. A introdução do veículo, no entanto, enfrenta fortes obstáculos legais e exigiria mudança profunda na legislação dos veículos combinados longos. / This paper investigates the feasibility of introducing the American twin trailer truck in the Brazilian road transport network. The twin is a five axle configuration with one tractor and two semi-trailers, coupled by an intermediate dolly. The investigation embraces not only economic questions (operational costs), but also operational aspects (freight density and volume, vehicle choice, line extension etc), technological questions (vehicles, trailers and dollies), weights and dimensions legislation, safety impacts (handling and stability, impact of traffic operations and statistic studies of accident rates) and the twin\'s interface with the highway facilities. The American and Canadian studies about twins are reviewed. The paper presents the technical characteristics of twins, the american weights and dimensions legislation and shows how the claim for more productivity in the transport industry and the low density freight growth have induced the use of longer combinations. The study compiles the main results presented in the literature about handling, stability and the twin trailer impact on the highway traffic and analyzes statistics comparing doubles with semi-trailer accident rates. The literature review leads to the conclusion that, althrough the twins could degrade slightly the vehicle traffic safety performance and accelerate the pavement wear, this degradation is overwhelmed by the reduction of the number of vehicles on the roads and direct and indirect transportation costs. The introduction of the win trailer truck in Brazil could be advantageous in order to replace tandem trucks on low demand routes. The savings in terminal times and the higher capacitiy of this configuration would cut costs as compared to the straight truck, semi-trailer and truck-and-trailer configurations, without relevant deterioration of the operational safety. The results of a large sample with brazilian LTL companies show that almost 50% of them operate with a freight density that would be ideal for twins. The twin\'s introduction, however, faces strong legal impediments in some markets, and only would be feasible if deep changes in the Brazilian weight and dimension regulations would be undertaken.
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