Functional safety of selected road vehicle system

Import 05/08/2014Obsahem této disertační práce je problematika funkční bezpečnosti v oblasti silničních vozidel, zvláště pak využití vhodných metod, postupů a modelů, v návaznosti na novou situaci spojenou se zaváděním nových norem. Práce byla zaměřena na návrh vhodných postupů a využití kvalitativní a kvantitativní analýzy spolehlivosti vybraných systémů silničních vozidel, jež významně ovlivňují bezpečnost silničního provozu. Pro ověření skutečné úrovně vybraných parametrů spolehlivosti zařízení byl navržen program zkoušek spolehlivosti. Pro hodnocení funkční bezpečnosti byly zvoleny postupy a nástroje, jež vycházejí z principů funkční bezpečnosti elektrických/ elektronických systémů souvisejících s bezpečností, popsaných v normě ČSN EN 61508 a ISO 26262. Disertační práce je tvořena částí teoretickou a experimentální a je rozčleněna do sedmi kapitol. V teoretické části práce jsou přehledně zpracovány a rozvinuty základní principy používané v oblasti funkční bezpečnosti. Byl vytvořen nový postup pro klasifikaci rizik pro silniční vozidla, který zjednodušuje proces posuzování rizik a přiřazení úrovně integrity bezpečnosti. Dále byly vybrány a popsány a rozpracovány metody pro kvalitativní a kvantitativní hodnocení funkční bezpečnosti. Všechny tyto metody jsou v souladu s doporučeními normy ISO 26262. Praktická část práce byla zaměřena na uplatnění postupů a metod navržených v teoretické části práce. Byly aplikovány na systém vstupních dveří autobusu a přední světlomet automobilu. V rámci kvalitativního hodnocení spolehlivosti byly s využitím postupu odpovídajících metod identifikovány jednotlivé funkce vstupních dveří autobusu a způsoby jejich selhání. Výsledkem je návrh různých opatření vedoucí ke snížení rizika. V rámci kvantitativní analýzy LED světla byl s využitím vhodných postupů vytvořen teoretický model bezporuchovosti pro náhodné poruchy hardware, na jehož základě by bylo možné výpočtem určit konkrétní číselné hodnoty ukazatelů funkční bezpečnosti.This thesis deals with the functional safety of road vehicles, especially the utilization of appropriate methods, procedures and models, in response to the new situation, coupled with the introduction of new standards. The thesis was focused on the design of appropriate procedures and the utilization of qualitative and quantitative reliability analysis of motor vehicles selected systems, which significantly affect the road safety. To verify the actual levels of selected reliability parameters of equipment the reliability tests program has been created. Selected procedures and tools for functional safety assessment, based on the principles of functional safety of electrical / electronic safety-related systems, as described in the standards EN 61508 and ISO 26262, have been chosen. Dissertation thesis consists of theoretical and experimental part, and is divided into seven chapters. In the theoretical part are clearly organized and evolved the basic principles used in the field of functional safety. The new procedure for the risk classification for road vehicles, which simplifies the process of risk assessment and allocation of safety integrity levels, has been created. Furthermore, the methods for qualitative and quantitative evaluation of functional safety have been selected, described and elaborated. All these methods are in accordance with the recommendations of ISO 26262. The practical part focuses on the application of the procedures and methods proposed in the theoretical part. These methods to the bus entrance door system and front headlight car have been applied. Each function of the bus entry doors and their failure modes using the appropriate methods and procedures have been identified in a qualitative assessment of reliability. The result is proposition of various measures to the risk reduction. The theoretical model of reliability of random hardware failures using the appropriate procedures in a quantitative assessment of reliability has been performed. The specific numerical values for the functional safety parameters, on the basis of the performed model have been calculated.Prezenční342 - Institut dopravyvyhově

SIMULATION MODEL OF THE SINGLECYLINDER COMBUSTION ENGINE MZ125

The use of one-dimensional CFD engine simulation is an essential tool to the engine development process. Engine design through simulation can drastically reduce time needed to perform engine experiments and prototyping, as most engine experiments can be simulated within the software

DESIGN OF ROAD VEHICLES COMPONENTS RESPECTING THE FUNCTIONAL SAFETY PRINCIPLES

This paper deals with the functional safety of road vehicles, especially the utilization of appropriate methods, procedures and models, in response to the new situation, coupled with the introduction of new standards. The paper was focused on the design of appropriate procedures and the utilization of qualitative and quantitative reliability analysis of motor vehicles selected systems, which significantly affect the road safety. To verify the actual levels of selected reliability parameters of equipment the reliability tests program has been created

The combustion engine intake manifold cfd modeling depending on the airbox configuration

The aim of the article is to present the possibilities of application of computational fluid dynamics (CFD) to modelling of air flow in combustion engine intake manifold depending on airbox configuration. The non-stationary flow occurs in internal combustion engines. This is a specific type of flow characterized by the fact that the variables depend not only on the position but also on the time. The intake manifold dimension and geometry strongly effects intake air amount. The basic target goal is to investigate how the intake trumpet position in the airbox impacts the filling of the combustion chamber. Furthermore, the effect of different distances between the trumpet neck and the airbox wall in this paper will be compared.Web of Science20215425542

N2O EMISSIONS FROM THE MOBILE SOURCES

Nitrous oxide (N2O) generally known for its anesthetic and hallucinogenic properties is oxide with the lowest valence of nitrogen among other oxides of nitrogen. In addition, it is the most stable nitrogen oxide in the environment. Measurement of the N2O emissions from the mobile sources has recently come forward and there are only few data at disposal. Due this reason we make described experiment

Internal combustion engine diagnostics using statistically processed Wiebe function

The aim of the article is to present the concept of an indirect diagnostic method using the assessment of the variability of the amount of released heat (mass fraction burn) and the heat release rate. The Wiebe function for the assessment of variability has been used. The Wiebe function parameters from the course of the high-pressure indication in the cylinder of internal combustion engine using linear regression have been calculated. From a sufficiently large number of measured samples, the upper and lower limits of the Wiebe function parameters have been statistically determined. Lower and upper limits characterize variability of the heat release process not only in terms of quantity but also in terms of heat release rate. The assessment of variability is thus more complicated than using one integral indicator, typically the mean value of amount of the released heat. The procedure enabling a more accurate estimation of heat generation beginning has been shown. For the combustion process variability assessment of the engine, statistical test of relative frequencies has been used.Web of Science23351150

DESIGN OF MOTORCYLE ACTIVE CHASSIS GEOMETRY CHANGE SYSTEM

Modern motorcycles have a number of electronic systems supporting their driving stability. These are usually adopted solutions used in automobiles. However, the idea of trying to affect the driving stability with the use of up-to-now changeless parameters such as wheelbase or trail is quite new. Such an innovative solution of motorcycle suspension with variable geometry dependent on driving conditions was designed in thesis by Jakub Šmiraus and constructed at the Institute of Transport VŠB - Technical university of Ostrava under tutelage of MSc Michal Richtář

UTILIZATION POSSIBILITIES OF THE HYBRID DRIVE IN LAND TRANSPORT

Článek se zabývá možnostmi využití hybridních pohonů v pozemní dopravěUtilization possibilities of hybrid drive in land transport in this paper will be describe

AERODYNAMIC INTERACTION OF TWO VEHICLES IN SELECTED DRIVE MODES

Článek se zabývá možnostmi využití hybridních pohonů v pozemní dopravěNumerical simulation of two vehicles aerodynamical interaction in selected drive modes in this paper will be described. aerdynamical intaraction of two vehicles in selected drive mode

Sledování základních dynamických charakteristik dopravního proudu sčítacím zařízením Viacount II

In this paper is shortly described counting facility Viacount II, which is dedicated for velocity and traffic flow composition measuring. Continuously results of the test measuring are described. Also additional possibilities of the counting facility utilization on the field of the Road Transport Laboratory activities are in this paper described.Příspěvek stručně popisuje sčítací zařízení Viacount, které je určené pro měření rychlosti a složení dopravního proudu v silničním provozu. Dále uvádí některé výsledky zkušebního měření na ulici Opavská v Ostravě-Porubě. Na závěr jsou nastíněny další možnosti využití zmíněného sčítacího zařízení v rámci činnosti Laboratoře silniční dopravy při Institutu dopravy (FS, VŠB-TU Ostrava)