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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Aktivní závěs kapoty / The Active Bonnet Hinge

Galda, Michal January 2013 (has links)
This thesis deals with designing the construction of an active bonnet hinge, tuning the kinematics and appropriate proportioning of individual parts of the hinge. The thesis consists of two main parts – the first part is an analysis of the current state of knowledge and the second part presents a designing the construction. The active hinge should serve as a safety element in automobiles to minimize consequences of head injury suffered during the collision of a pedestrian with an automobile.
2

Simulace nárazu vozidla na dolní končetinu chodce / Car Impact Simulation on Pedestrian Leg

Jaška, Lukáš January 2008 (has links)
This thesis seeks to simulate the impact on the human foot on the car bumper. The opening section deals with requirements as to the current passive safety features aiming to mitigate the consequences of such impact. The thesis also describes the construction of a human foot impactor, its certification via both static and dynamic tests, a simulation of the cash test and its evaluation. The designed model as well as the simulation procedure have been led according to the current Euro NCAP specifications.
3

Studie vlivu vlastností materiálu na simulaci nárazu hlavy chodce na kapotu / Study of Material Properties Influence on Pedestrian Head Impact on Bonnet

Coufal, Tomáš January 2009 (has links)
The thesis describes the complex of basic testing procedures conducted by Euro NCAP company with a view to the examination of pedestrian protection in accordance with EEVC WG 17 and topical instruments used at passenger vehicles for pedestrian protection. It includes a detailed procedure of the creation of an adult head impactor including its certification and the formation of its impact on the bonnet of the vehicle. It is specialized in the studies how material properties influence the size of HIC criterion.
4

Homogenní kapota - chování při nárazech impaktorem hlavy / Homogeneous Bonnet - Behavior at Head Impactor Impacts

Kadrmas, Lukáš January 2009 (has links)
This thesis deals with the subject of crash tests Euro NCAP, concretely child-head impact test to the car bonnet. Object of thesis is make homogeneous car bonnet, where will remove stiffness places and also the bonnet global stiffness won´t be worst. The bonnet must carry out limits for pedestrian protection.
5

Protection of Standing and Seated Pedestrians Using Finite Element Analysis

Grindle, Daniel Mark 06 June 2023 (has links)
In the United States pedestrian fatalities in vehicle impacts have increased over the last 40 years and pedestrians who use wheelchairs (seated pedestrians) have higher mortality rates than standing pedestrians in vehicle impacts. Standing pedestrian protection has generated increased attention and regulatory action but seated pedestrian protection has not been investigated or regulated. To investigate standing pedestrian safety researchers use finite element models of the human body and simulate vehicle impacts. Finite element models can be useful but they are limited by their biofidelity, and often simplify the complex anatomy of the human body for the sake of computational expense. If modeling results are to be taken seriously to investigate standing and seated pedestrian protection, then further model development and validation is necessary. In this dissertation a finite element model of a male 50th percentile standing pedestrian was enhanced and validated for use in vehicle impact simulations. The standing pedestrian model lower body was further enhanced and validated to study the importance of stabilizing components of the knee. These updates to the standing pedestrian knee joint were imported into an occupant model and further validated in occupant loading scenarios. The updated standing pedestrian was used to explore the effect of modeling component failure on vehicle impact. Simplified and detailed occupant models were used to model seated pedestrians in vehicle impacts to explore seated pedestrian injury risks. The seated pedestrian head and brain typically reported the highest risks of injury, usually because of head-ground contact. A lap belt, airbag vest, and bicycle helmet were tested on the seated pedestrians. The lap belt and airbag vest typically increased injury risks and the bicycle helmet reduced injury risks. The work presented in this dissertation may inform future modelers, vehicle designers, and safety equipment developers on standing and seated pedestrian safety. / Doctor of Philosophy / In the United States pedestrian fatalities in vehicle impacts have increased over the last 40 years and pedestrians who use wheelchairs (seated pedestrians) have higher death rates than standing pedestrians in vehicle impacts. Research studies have examined how to protect standing pedestrians, but not seated pedestrians. The goal of this work was to begin investigating seated pedestrian safety. To investigate standing pedestrian safety researchers use computer models (finite element models) of the human body and simulate vehicle impacts. These finite element models can be useful but they are limited by how life like they are. If modeling results are to be taken seriously to investigate standing and seated pedestrian protection, then further model improvement is necessary. In this dissertation a finite element model of an average North American male standing pedestrian was improved for use in vehicle impact simulations. The standing pedestrian model lower body was further improved to study the importance of stabilizing components of the knee. These updates to the standing pedestrian knee joint were imported into a seated model with the same anatomy. Simplified and detailed seated models were used to model seated pedestrians in vehicle impacts to explore seated pedestrian injury risks. The seated pedestrian head and brain typically reported the highest risks of injury, usually because of head-ground contact. A lap belt, airbag vest, and bicycle helmet were tested on the seated pedestrians. The lap belt and airbag vest typically increased injury risks and the bicycle helmet reduced injury risks. The work presented in this dissertation may inform future modelers, vehicle designers, and safety equipment developers on standing and seated pedestrian safety.
6

An Efficient Vision-Based Pedestrian Detection and Tracking System for ITS Applications

Zuo, Tianyu January 2014 (has links)
In this thesis, a novel Pedestrian Protection System (PPS), composed of the Pedestrian Detection System (PDS) and the Pedestrian Tracking System (PTS), was proposed. The PPS is a supplementary application for the Advanced Driver Assistance System, which is used to avoid collisions between vehicles and pedestrians. The Pedestrian Detection System (PDS) is used to detect pedestrians from near to far ranges with the feature-classi er-based detection method (HOG + SVM). To achieve pedestrian detection from near to far ranges, a novel structure was proposed. The structure of our PDS consists of two cameras (called CS and CL separately). The CS is equipped with a short focal length lens to detect pedestrians in near-to-mid range; and, the CL is equipped with a long focal length lens to detect pedestrians in mid-to-far range. To accelerate the processing speed of pedestrian detection, the parallel computing capacity of GPU was utilized in the PDS. The synchronization algorithm is also introduced to synchronize the detection results of CS and CL. Based on the novel pedestrian detection structure, the detection process can reach a distance which is more than 130 meters away without decreasing detection accuracy. The detection range can be extended more than 100 meters without decreasing the processing speed of pedestrian detection. Afterwards, an algorithm to eliminate duplicate detection results is proposed to improve the detection accuracy. The Pedestrian Tracking System (PTS) is applied following the Pedestrian Detection System. The PTS is used to track the movement trajectory of pedestrians and to predict the future motion and movement direction. A C + + class (called pedestrianTracking class, which is short for PTC) was generated to operate the tracking process for every detected pedestrian. The Kalman lter is the main algorithm inside the PTC. During the operation of PPS, the nal detection results of each frame from PDS will be transmitted to the PTS to enable the tracking process. The new detection results will be used to update the existing tracking results in the PTS. Moreover, if there is a newly detected pedestrian, a new process will be generated to track the pedestrian in the PTS. Based on the tracking results in PTS, the movement trajectory of pedestrians can be obtained and their future motion and movement direction can be predicted. Two kinds of alerts are generated based on the predictions: warning alert and dangerous alert. These two alerts represent di erent situations; and, they will alert drivers to the upcoming situations. Based on the predictions and alerts, the collisions can be prevented e ectively. The safety of pedestrians can be guaranteed.
7

Concept of an enhanced V2X pedestrian collision avoidance system with a cost function–based pedestrian model

Kotte, Jens, Schmeichel, Carsten, Zlocki, Adrian, Gathmann, Hauke, Eckstein, Lutz 29 September 2020 (has links)
Objective: State-of-the-art collision avoidance and collision mitigation systems predict the behavior of pedestrians based on trivial models that assume a constant acceleration or velocity. New sources of sensor information—for example, smart devices such as smartphones, tablets, smartwatches, etc.—can support enhanced pedestrian behavior models. The objective of this article is the development and implementation of a V2Xpedestrian collision avoidance system that uses new information sources. Methods: A literature review of existing state-of-the-art pedestrian collision avoidance systems, pedestrian behavior models in advanced driver assistance systems (ADAS), and traffic simulations is conducted together with an analysis of existing studies on typical pedestrian patterns in traffic. Based on this analysis, possible parameters for predicting pedestrian behavior were investigated. The results led to new requirements from which a concept was developed and implemented. Results: The analysis of typical pedestrian behavior patterns in traffic situations showed the complexity of predicting pedestrian behavior. Requirements for an improved behavior prediction were derived. A concept for a V2X collision avoidance system, based on a cost function that predicts pedestrian near future presence, and its implementation is presented. The concept presented considers several challenges such as information privacy, inaccuracies of the localization, and inaccuracies of the prediction. Conclusion: A concept for an enhanced V2X pedestrian collision avoidance system was developed and introduced. The concept uses new information sources such as smart devices to improve the prediction of the pedestrian's presence in the near future and considers challenges that come along with the usage of these information sources.
8

Análise comparativa pelo método dos elementos finitos entre diferentes estruturas internas de capôs de veículos visando à proteção ao pedestre em caso de atropelamento. / Comparative finite element analysis of different vehicle hood inner panels, with the objective to minimize the injuries to the pedestrian in case of a running over accident.

Ferreira, Anderson Sirolli 26 March 2010 (has links)
Este estudo foca uma análise comparativa de diferentes painéis internos de capôs de veículos, com o objetivo de minimizar as lesões ao pedestre em caso de um atropelamento. As lesões na cabeça do pedestre são medidas através de um modelo em elementos finitos de uma cabeça padrão de acordo com o comitê europeu de melhorias da segurança de veículos. Os valores de desaceleração obtidos nas análises são comparados com valores toleráveis de acordo com o critério HIC (Head Injury Criteria), criado pela NHTSA (National Highway Traffic Safety Administration). Baseando-se nos resultados obtidos demonstra-se a influência dos tipos de estruturas internas de capô e recomenda-se a melhor estrutura para aplicações na indústria automobilística. / This study focus on comparative analysis of different vehicle hood inner panels, with the objective to minimize the injuries to the pedestrian in case of a running over accident. The method to measure the injuries in the head of the pedestrian will be made through a finite element model of a standard head in accordance with the European committee of improvements of the security of vehicles. The values of decelerations obtained in the analysis are compared with human tolerance levels according to HIC criteria (Head Injury Criteria), created by NHTSA (National Highway Traffic Safety Administration). Based on the finite element analysis results, this study demonstrate the influence of different hood inner panels and recommends the best structure to be applied by automobile industry.
9

Análise comparativa pelo método dos elementos finitos entre diferentes estruturas internas de capôs de veículos visando à proteção ao pedestre em caso de atropelamento. / Comparative finite element analysis of different vehicle hood inner panels, with the objective to minimize the injuries to the pedestrian in case of a running over accident.

Anderson Sirolli Ferreira 26 March 2010 (has links)
Este estudo foca uma análise comparativa de diferentes painéis internos de capôs de veículos, com o objetivo de minimizar as lesões ao pedestre em caso de um atropelamento. As lesões na cabeça do pedestre são medidas através de um modelo em elementos finitos de uma cabeça padrão de acordo com o comitê europeu de melhorias da segurança de veículos. Os valores de desaceleração obtidos nas análises são comparados com valores toleráveis de acordo com o critério HIC (Head Injury Criteria), criado pela NHTSA (National Highway Traffic Safety Administration). Baseando-se nos resultados obtidos demonstra-se a influência dos tipos de estruturas internas de capô e recomenda-se a melhor estrutura para aplicações na indústria automobilística. / This study focus on comparative analysis of different vehicle hood inner panels, with the objective to minimize the injuries to the pedestrian in case of a running over accident. The method to measure the injuries in the head of the pedestrian will be made through a finite element model of a standard head in accordance with the European committee of improvements of the security of vehicles. The values of decelerations obtained in the analysis are compared with human tolerance levels according to HIC criteria (Head Injury Criteria), created by NHTSA (National Highway Traffic Safety Administration). Based on the finite element analysis results, this study demonstrate the influence of different hood inner panels and recommends the best structure to be applied by automobile industry.

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