WorldWideScience

Sample records for automotive brake disc

  1. Residual stresses in a cast iron automotive brake disc rotor

    International Nuclear Information System (INIS)

    Runout, and consequent juddering and pulsation through the brake pedal, is a multi-million dollar per year warranty problem for car manufacturers. There is some suspicion that the runout can be caused by relaxation of residual casting stresses when the disc is overheated during severe-braking episodes. We report here neutron-diffraction measurements of the levels and distribution of residual strains in a used cast iron brake disc rotor. The difficulties of measuring stresses in grey cast iron are outlined and three-dimensional residual-strain distributions are presented and their possible effects discussed

  2. Constitutive model for flake graphite cast iron automotive brake discs: induced anisotropic damage model under complex loadings

    Science.gov (United States)

    Augustins, L.; Billardon, R.; Hild, F.

    2016-01-01

    The present paper details an elasto-viscoplastic constitutive model for automotive brake discs made of flake graphite cast iron. In a companion paper (Augustins et al. in Contin Mech Thermodyn, 2015), the authors proposed a one-dimensional setting appropriate for representing the complex behavior of the material (i.e., asymmetry between tensile and compressive loadings) under anisothermal conditions. The generalization of this 1D model to 3D cases on a volume element and the associated challenges are addressed. A direct transposition is not possible, and an alternative solution without unilateral conditions is first proposed. Induced anisotropic damage and associated constitutive laws are then introduced. The transition from the volume element to the real structure and the numerical implementation require a specific basis change. Brake disc simulations with this constitutive model show that unilateral conditions are needed for the friction bands. A damage deactivation procedure is therefore defined.

  3. CFD design analysis of ventilated disc brakes

    OpenAIRE

    Pulugundla, Gautam

    2008-01-01

    This thesis reports the numerical investigation of the automotive ventilated disc brake rotor. Disc brakes operate on the principle of friction by converting kinetic energy into heat energy. The main objective of a disc brake rotor is to store this heat energy and dissipate it as soon as possible. This work is carried out in a area where there is very limited understanding. Commercial CFD code FLUENT was used for carrying out the simulations with the rotor rotating in still ...

  4. A Review of a Study on Disc Brake Noise

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    With the development of the automotive industry, disc brake noise has become an issue of growing concern to the automotive industry and customers. In this paper, the types of disc brake noise have been discussed. Ajter that, the theories and models that have been proposed as an explanation of brake squeal are reviewed. On the basis of these theories and models, some example simulations of disc brake squeal which use the Finite Element method and mathematical model have been introduced.

  5. Constitutive model for flake graphite cast iron automotive brake discs: from macroscopic multiscale models to a 1D rheological description

    Science.gov (United States)

    Augustins, L.; Billardon, R.; Hild, F.

    2016-07-01

    One of the critical points of the thermomechanical fatigue design process is the correct description of the cyclic behavior of the material. This work focuses on the material of automotive brake discs, namely flake graphite cast iron. The specificity of this material is its asymmetric behavior under tensile and compressive loadings, which is due to the shape of graphite that acts as small cracks. Multiscale models inspired from the literature are first presented. They lead to a good description of the material behavior under cyclic loadings. An elastoviscoplastic constitutive model is then proposed in a one-dimensional setting in order to accurately describe cyclic tests from room temperature up to {600^{circ}{C}}.

  6. TGV disc brake squeal

    Science.gov (United States)

    Lorang, X.; Foy-Margiocchi, F.; Nguyen, Q. S.; Gautier, P. E.

    2006-06-01

    The discomfort generated by the noise emission of braking systems in trains has aroused recently many studies on the mechanical modelling of brake noise in France. A theoretical and numerical discussion on the phenomenon of brake squeal is given in this paper in relation with some experimental data. This study is based upon a flutter instability analysis giving unstable modes of the brake system under the contact and Coulomb friction.

  7. Numerical Modeling of Disc Brake System in Frictional Contact

    Directory of Open Access Journals (Sweden)

    A. Belhocine

    2014-03-01

    Full Text Available Safety aspect in automotive engineering has been considered as a number one priority in development of new vehicle. Each single system has been studied and developed in order to meet safety requirement. Instead of having air bag, good suspension systems, good handling and safe cornering, there is one most critical system in the vehicle which is brake systems. The objective of this work is to investigate and analyse the temperature distribution of rotor disc during braking operation using ANSYS Multiphysics. The work uses the finite element analysis techniques to predict the temperature distribution on the full and ventilated brake disc and to identify the critical temperature of the rotor by holding account certain parameters such as; the material used, the geometric design of the disc and the mode of braking. The analysis also gives us, the heat flux distribution for the two discs.

  8. Aerodynamic investigations of ventilated brake discs.

    OpenAIRE

    Parish, D.; MacManus, David G.

    2005-01-01

    The heat dissipation and performance of a ventilated brake disc strongly depends on the aerodynamic characteristics of the flow through the rotor passages. The aim of this investigation was to provide an improved understanding of ventilated brake rotor flow phenomena, with a view to improving heat dissipation, as well as providing a measurement data set for validation of computational fluid dynamics methods. The flow fields at the exit of four different brake rotor geometrie...

  9. Topology Optimization in Automotive Brake Pedal Redesign

    Directory of Open Access Journals (Sweden)

    Mohd Nizam Sudin

    2014-03-01

    Full Text Available Nowadays, automotive industry is continuing to strive for light weight vehicle in improving fuel efficiency and emissions reduction. To produce a better performance car it is important to design vehicles with optimum weight. In order to reduce the weight of vehicle without sacrificing its integrity, this project aims to employ topology optimization technique to propose an optimal design of an automotive component in early phase of product development. In this project the material used for an existing brake pedal is unchanged as this study focuses on reducing weight of existing brake pedal without material substitution. The digital model of an existing brake pedal was generated using CATIA V5 solid modelling software. Topology optimization was performed by using Altair Optistruct software under linear static stress analysis. Finally, a new light weight design brake pedal is proposed. The result of the study shows that the weight of a new designed brake pedal was 22% less as compared to an existing brake pedal without sacrificing its performance requirement.

  10. Nonlinear transient and chaotic interactions in disc brake squeal

    Science.gov (United States)

    Oberst, S.; Lai, J. C. S.

    2015-04-01

    In automotive disc-brake squeal, most numerical studies have been focussed on the prediction of unstable vibration modes in the frequency domain using the complex eigenvalue analysis. However, the magnitude of the positive real part of a complex eigenvalue is an unreliable indicator of squeal occurrence. Although nonlinearities have been shown to play a significant role in brake squeal, transient nonlinear time domain analyses have rarely been applied owing to high computational costs. Here the complex eigenvalue analysis, the direct steady-state analysis and the transient nonlinear time domain analysis are applied to an isotropic pad-on-disc finite element model representing a simple model of a brake system. While in this investigation, in-plane pad-mode instabilities are not detected by the complex eigenvalue analysis, the dissipated energy obtained by the direct steady-state analysis of the model subjected to harmonic contact pressure excitation is negative at frequencies of pad modes, indicating a potential for instabilities. Transient nonlinear time domain analysis of the pad and disc dynamics reveal that in-plane pad vibrations excite a dominant out-of-plane disc mode. For intermittently chaotic pad motion, the disc dynamics is quasi-periodic; and for chaotic motion of the pad, a toroidal attractor is found for the disc's out-of-plane motion. Nonlinear interactions between the pad and the disc highlight that different parts in a brake system display different dynamic behaviour and need to be analysed separately. The type II intermittency route to chaos could be the cause for the experimentally observed instantaneous mode squeal.

  11. Electric disc brakes hold nuclear aircraft carriers

    International Nuclear Information System (INIS)

    Two nuclear-powered aircraft carriers, the U.S.S. Nimitz and the soon-to-be-completed U.S.S. Dwight D. Eisenhower, use electric disc brakes to stop and hold lines on warping and mooring capstans during docking maneuvers and mooring operations

  12. Eddy current braking experiment using brake disc from aluminium series of A16061 and A17075

    International Nuclear Information System (INIS)

    The electromagnetic braking using eddy current was studied, focused on two series of aluminium as the brake disc which are A16061 and A17075. This paper presents the comparison for both series in a few varied parameters related to eddy current braking such as air-gap, number of turns and brake disc thickness. Optical tachometer has been used along with PULSE analyzer to capture the speed (rpm) and time (s). The findings shows that the smaller the air-gap, the larger of electromagnet turns and the thicker disc thickness is, will generate higher braking torque to stop the rotational motion of disc brake and give great performance for eddy current braking. Thos parameters that been evaluated also addressed a potential on expanding this knowledge to develop an electromagnetic braking system to replace the conventional braking system.

  13. Research on Heat-Mechanical Coupling of Ventilated Disc Brakes under the Condition of Emergency Braking

    Science.gov (United States)

    Tan, Xuelong; Zhang, Jian; Tang, Wenxian; Zhang, Yang

    Taking the ventilated disc brake in some company as research object, and using UG to build 3D models of brake disc and pad, and making use of ABAQUS/Standard to set up two parts' finite element model, via the decelerated motion of actual simulation brake disc, which gets ventilated disc brake in the case of emergency breaking in time and space distribution of conditions of temperature and stress field, summarizes the distribution of temperature field and stress field, proves complex coupling between temperature, stress, and supplies the direct basis for brake's fatigue life analysis.

  14. Quality control of cast brake discs

    Directory of Open Access Journals (Sweden)

    M. Stawarz

    2008-04-01

    Full Text Available The largest industrial application so far have the gray cast irons which are characterized by low tensile and bending strength, while at the same time they have good ultimate comprehensive strength. Additionally, the fatigue strength of gray cast irons is comparatively low and they are only to some extend sensitive for the surface waters effects. Cast iron is the material, which is comparatively easy to be processed, and for this reason – it is not expensive. Brake discs are exploited in particularly hard conditions. They must be resistant both against the thermal fatigue and abrasion wearing (at dry friction as well as against seizing, corrosion and mechanical load [1-3]. The gray cast iron, better than other materials, fulfills all the requirements necessary for making the material for the casts resistant against such tough conditions. This work reflects the researches aiming to define the quality of cast brake discs (ventilated and non-ventilated ones upon a period of their exploitation in real conditions. The following researches were performed: evaluations of the disc surface condition, measurement of disc thickness, examination of run – out flank and metallographic analysis. In order to more detailed recognition of mechanisms and reasons of brake discs wearing in real conditions, one should conduct additional examinations: computer analysis of the microstructure, chemical composition analysis, etc., as well as study of the technology of their production in foundries, where they are manufactured [4]. By obtaining the full set of the mentioned above data one can draw final conclusions and remove causes of possible defects.

  15. Zavorne ploščice iz karboniziranega materiala za zavorne diske iz C/C-SiC: Carbonised-material-based brake pads for a C/C-SiC composite brake disc:

    OpenAIRE

    Stadler, Zmago

    2001-01-01

    Letely the brake discs from carbon-fibre-reinforced carbon composites infiltrated by silicon (LSI-process) have become very interesting for automotive brakes applications. Composite materials with a hard SiC layer on the surface of the disc (C/C-SiC) or composites with the fibre-reinforced ceramic structure (C/SiC) need the right brake-lining materials. The results of our new-brake-lining-material investigation for C/C-SiC brake discs are presented. The influence of some particular additives ...

  16. Comparative Frictional Analysis of Automobile Drum and Disc Brakes

    Directory of Open Access Journals (Sweden)

    H.P. Khairnar

    2016-03-01

    Full Text Available In the present work, a comparative frictional behaviour of drum brakes and disc brakes in automobiles has been investigated. The influential factors; contact force and friction radius were modeled for the estimation of the friction coefficient for drum as well as disc brakes. The effect of contact force and friction radius is studied with varying conditions of parameters; longitudinal force, caliper force and torque on piston side as well as non-piston side. The numerical results obtained have been compared with the similar obtained from virtual Matlab/Simulink models for drum and disc brakes. The results evidenced that friction radius predominantly affects brake pressure and thus the friction coefficient, also the increase in contact force resulted with decrease in friction coefficient both for drum and disc brakes. Further it has been found that disc brakes exhibit gradual decrease of friction coefficient due to the equitable distribution of braking effort while drum brake presents sudden variations in friction coefficient. It can be revealed that frictional behaviour of disc brake is more consistent than drum brake.

  17. Comparative Frictional Analysis of Automobile Drum and Disc Brakes

    OpenAIRE

    H.P. Khairnar; V.M. Phalle; S. S. Mantha

    2016-01-01

    In the present work, a comparative frictional behaviour of drum brakes and disc brakes in automobiles has been investigated. The influential factors; contact force and friction radius were modeled for the estimation of the friction coefficient for drum as well as disc brakes. The effect of contact force and friction radius is studied with varying conditions of parameters; longitudinal force, caliper force and torque on piston side as well as non-piston side. The numerical results obtained hav...

  18. A Comparative Study on Automotive Brake Testing Standards

    Science.gov (United States)

    Kumbhar, Bhau Kashinath; Patil, Satyajit Ramchandra; Sawant, Suresh Maruti

    2016-06-01

    Performance testing of automotive brakes involves determination of stopping time, distance and deceleration level. Braking performance of an automobile is required to be ensured for various surfaces like dry, wet, concrete, bitumen etc. as well as for prolonged applications. Various brake testing standards are used worldwide to assure vehicle and pedestrian safety. This article presents methodologies used for automotive service brake testing for two wheelers. The main contribution of this work lies in comparative study of three main brake testing standards; viz. Indian Standards, Federal Motor Vehicle Safety Standards and European Economic Commission Standards. This study shall help the policy makers to choose the best criteria out of these three while formulating newer edition of testing standards.

  19. The Effect of Cashew to The Friction Performance Of Automotive Brake Linings

    OpenAIRE

    Timur, Mustafa; Kılıç, Halil; Sugözü, İlker

    2013-01-01

    Brake linings used in automotive disks are usually composed of various components. Expected properties from a brake lining are appropriate standart value of wear resist, friction coefficient and also economical value. Brake lining extremely warms up during braking due to friction. The braking performance of brake lining changes and braking lining is subject to mecanical deformation due to excessive temperature. In recent twenty years in consequence of fast development in automotive technology...

  20. Marble Waste Using Produced of Automotive Brake Pad of Friction Coefficient Different Pad Brake Pads With Comprasion

    Directory of Open Access Journals (Sweden)

    Mustafa Timur

    2013-01-01

    Full Text Available Brake linings used in automotive disks are usually composed of various components. Expected properties from a brake lining are appropriate standard value of wear resist, friction coefficient. Brake lining extremely warms up during braking due to friction. The braking performance of brake lining changes and braking lining is subject to mechanical deformation due to excessive temperature. In this study, it is aimed to revaluate the waste of marble dust in marble processing in Turkey. For this purpose, marble wastes are grinded to produce marble dust. The brake lining, which has new formulation, is produced by using various additive materials. The friction performances of the brake pads produced were compared with those of other firms and the results were show in graphics. Therefore, the effect of marble dust on braking performance is investigated. It is observed that a favorable result in braking performance is obtained using of marble dust.

  1. Squeal analysis of ventilated disc brake using ansys

    Directory of Open Access Journals (Sweden)

    Ahmed Abdel-Naser, Ibrahim Ahmed, Essam Allam, Sabry Allam, Shawki Abouel-seoud

    2012-01-01

    Full Text Available It is well-known that automobile brakes can generate several kinds of noises. Among them is squeal, a noise in the 1-15 kHz range. It is commonly accepted that brake squeal is initiated by instability due to the friction forces, leading to self excited vibrations. To predict the onset of brake instability, a modal analysis of the prestressed structure can be performed on an improved dynamic finite element model of ventilated disc brake with friction coupling. An unsymmetric stiffness matrix is a result of the friction coupling between the brake pad and disc; this may lead to complex eigenfrequencies. The complex eigenvalue method (Unsymmetric solver used to analyse mode shapes associated with the predicted natural frequency. Creating the element of Matrix27 between the ventilated disc and pad was very important in studying the squeal of the coupled ventilated disc brake. The results demonstrated that the FEM for the coupled ventilated rotor and pad showed a good interaction between the non-linear contact and the linear modal analysis. Furthermore, the unsymmetric solver showed that the modes of the coupled disc-pad contained two types of mode. The first type was normal mode, which did not contain an imaginary part while the second type was complex mode that contained real and imaginary parts. Moreover, complex eigenvalue analysis predicted always more unstable modes than the number of squeal frequencies that really occur in the brake system. The maximum squeal index was observed at mode 16 and at frequency of 4083 Hz with instability of 480 sec-1. However; the tendency of instability (TOI for the system at contact stiffness of 1 GN/m was 59 that gave the lowest instability of the system.

  2. Investigation of Product Performance of Al-Metal Matrix Composites Brake Disc using Finite Element Analysis

    Science.gov (United States)

    Fatchurrohman, N.; Marini, C. D.; Suraya, S.; Iqbal, AKM Asif

    2016-02-01

    The increasing demand of fuel efficiency and light weight components in automobile sectors have led to the development of advanced material parts with improved performance. A specific class of MMCs which has gained a lot of attention due to its potential is aluminium metal matrix composites (Al-MMCs). Product performance investigation of Al- MMCs is presented in this article, where an Al-MMCs brake disc is analyzed using finite element analysis. The objective is to identify the potentiality of replacing the conventional iron brake disc with Al-MMCs brake disc. The simulation results suggested that the MMCs brake disc provided better thermal and mechanical performance as compared to the conventional cast iron brake disc. Although, the Al-MMCs brake disc dissipated higher maximum temperature compared to cast iron brake disc's maximum temperature. The Al-MMCs brake disc showed a well distributed temperature than the cast iron brake disc. The high temperature developed at the ring of the disc and heat was dissipated in circumferential direction. Moreover, better thermal dissipation and conduction at brake disc rotor surface played a major influence on the stress. As a comparison, the maximum stress and strain of Al-MMCs brake disc was lower than that induced on the cast iron brake disc.

  3. Investigation on hardness and impact resistance of automotive brake pad composed with rice husk dust

    Science.gov (United States)

    Bahari, Shahril Anuar; Isa, Khairul Hafizee; Kassim, Masitah Abu; Mohamed, Zulkifli; Othman, Eliasidi Abu

    2012-06-01

    In this study, hardness and impact resistance properties of automotive brake pad composed with rice husk dust (RHD) were documented. RHD was mixed with other metallic and synthetic ingredients of automotive brake pad. To obtain RHD, rice husk was ground and dried to 1 - 3% moisture content. The RHD was screened to obtain different dust sizes (80 and 100-mesh) before it was mixed with other materials at different percentages of composition (10 and 30%). The mixture was then pressed to produce brake pad. Rockwell hardness testing machine was used in hardness determination, while Izod impact testing machine was used in impact resistance determination. Hardness resistance of automotive brake pad mixed with 10% composition and 80-mesh size of RHD was significantly higher than 100-mesh. Hardness resistance of automotive brake pad mixed with 30% composition and 100-mesh size of RHD was slightly higher than 80 mesh. However, based on analysis, the difference was not significant. According to the result, hardness resistance of automotive brake pad mixed with 30% composition of RHD was higher than 10%. RHD has filled up the space and enhanced the micro structural behaviour of automotive brake pad. Impact resistance of automotive brake pad mixed with 10% composition and 80-mesh size of RHD was insignificantly higher than 100-mesh. Impact resistance of automotive brake pad mixed with 30% composition and 80-mesh size of RHD was significantly higher than 100 mesh. Large RHD size has increased the capability to resist high-rated impact loading. The impact energy was distributed over wider area for larger particle size. This factor has increased the impact resistance of automotive brake pad from large dust size. Impact resistance of automotive brake pad mixed with 80-mesh size and 30% composition of RHD was higher than 10%. In contrast, impact resistance of automotive brake pad mixed with 100-mesh size and 10% composition of RHD was higher than 30%. However, the difference was not

  4. Evaluation of palm kernel fibers (PKFs for production of asbestos-free automotive brake pads

    Directory of Open Access Journals (Sweden)

    K.K. Ikpambese

    2016-01-01

    Full Text Available In this study, asbestos-free automotive brake pads produced from palm kernel fibers with epoxy-resin binder was evaluated. Resins varied in formulations and properties such as friction coefficient, wear rate, hardness test, porosity, noise level, temperature, specific gravity, stopping time, moisture effects, surface roughness, oil and water absorptions rates, and microstructure examination were investigated. Other basic engineering properties of mechanical overload, thermal deformation fading behaviour shear strength, cracking resistance, over-heat recovery, and effect on rotor disc, caliper pressure, pad grip effect and pad dusting effect were also investigated. The results obtained indicated that the wear rate, coefficient of friction, noise level, temperature, and stopping time of the produced brake pads increased as the speed increases. The results also show that porosity, hardness, moisture content, specific gravity, surface roughness, and oil and water absorption rates remained constant with increase in speed. The result of microstructure examination revealed that worm surfaces were characterized by abrasion wear where the asperities were ploughed thereby exposing the white region of palm kernel fibers, thus increasing the smoothness of the friction materials. Sample S6 with composition of 40% epoxy-resin, 10% palm wastes, 6% Al2O3, 29% graphite, and 15% calcium carbonate gave better properties. The result indicated that palm kernel fibers can be effectively used as a replacement for asbestos in brake pad production.

  5. A low cost, light weight cenosphere–aluminium composite for brake disc application

    Indian Academy of Sciences (India)

    V Saravanan; P R Thyla; S R Balakrishnan

    2016-02-01

    The commonly used composite material for brake rotor consists of silicon carbide (SiC) or aluminium oxide (Al$_2$O$_3$) particles which are more expensive. The weight of conventionally used composite is more compared to base alloy. The aim of this paper is to develop a light weight material for brake disc applications thereby substituting base alloy and conventional composite. This analysis led to 10 vol% cenosphere reinforced aluminium alloy (AA) 6063 composite as the most appropriate material for brake disc. To ensure the manufacturability of composite, composite brake rotor was casted using the sand casting technique and was machined to achieve the final component. Thermal capability of brake disc was ensured by studying temperature variation through vehicle testing procedure of disc brake. Cost reduction is one of the important benefit acquired using cenosphere reinforced composite. This was ensured by cost estimation and analysis. The cost estimated to manufacture the AA6063 brake disc was compared with composite cost.

  6. On Airborne Wear Particles Emissions ofCommercial Disc Brake Materials– A Pin on Disc Simulation

    OpenAIRE

    Söderberg, Anders; Wahlström, Jens; Olander, Lars; Jansson, Anders; Olofsson, Ulf

    2008-01-01

    A novel test method was used to study the concentration and size distribution of airborne wear particles from disc brake materials. A pin-on-disc tribometer equipped with particle counting instruments was used as test equipment. Four different nonasbestoses-organic (NAO) linings for the U.S. market and four different low metallic linings for the EU market were tested against material from gray cast iron rotors. The result indicates that the low metallic linings are more aggressive to the roto...

  7. Thermo-Mechanical Simulation of Brake Disc Frictional Character by Moment of Inertia

    OpenAIRE

    Fei Gao

    2014-01-01

    The distribution of temperatures gradient and thermal stress of brake disc has been simulated by FEM code to make brake disc thermal stress more homogenously. In this study, using moment of inertia to simulate the realistic brake process instead of theoretically predefines the train deceleration rate, nonlinear deceleration rate and thermo-mechanical behavior has been revealed. The FEM models build upon LS-DYNA® thermo-mechanical code and contact algorithm. Non-uniform temperature alone disc ...

  8. Development of fly ash-based automotive brake lining

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, S.; Chugh, Y.P. [South Illinois University, Carbondale, IL (United States). College of Engineering

    2007-07-15

    Coal-fired power plants all over the world generate huge amounts of fly ash each year, 70 million tons of which are produced in the United States alone. Only 40% of all fly ashes generated in the USA find beneficial applications and rest have to be disposed off, which is burden for the generation industry. Fly ash particles possess certain characteristics that make them suitable for use in friction composites as a filter material. An attempt has been made through this research to incorporate more than 50wt% of fly ash particles in automotive brake lining friction composites. This paper presents the research carried out on development of friction composites, using fly ash obtained from a specific power plant in Illinois. Ingredients such as phenolic resin, aramid pulp, glass fiber, potassium titanate, graphite, aluminum fiber and copper powder were used in the composite development phase, in addition to the fly ash. The developed brake lining composites have exhibited consistent coefficients of friction in the range of 0.35-0.4, and wear rates lower than 12wt%.

  9. Fallback level concepts for conventional and by-wire automotive brake systems

    International Nuclear Information System (INIS)

    Brake-by-wire represents the replacement of traditional brake components such as pumps, hoses, fluids, brake boosters, and master cylinders by electronic sensors and actuators. The different design of these brake concepts poses new challenges for the automotive industry with regard to availability and fallback levels in comparison to standard conventional brake systems. This contribution focuses on the development of appropriate fallback level concepts. Hardware-in-the-loop (HIL) techniques and field trials will be used to investigate the performance and the usability of such systems.

  10. Optimal design of an automotive magnetorheological brake considering geometric dimensions and zero-field friction heat

    International Nuclear Information System (INIS)

    This paper presents an optimal design of a magnetorheological (MR) brake for a middle-sized passenger car which can replace a conventional hydraulic disc-type brake. In the optimization, the required braking torque, the temperature due to zero-field friction of MR fluid, the mass of the brake system and all significant geometric dimensions are considered. After describing the configuration, the braking torque of the proposed MR brake is derived on the basis of the field-dependent Bingham and Herschel–Bulkley rheological model of the MR fluid. The optimal design of the MR brake is then analyzed taking into account available space, mass, braking torque and steady heat generated by zero-field friction torque of the MR brake. The optimization procedure based on the finite element analysis integrated with an optimization tool is proposed to obtain optimal geometric dimensions of the MR brake. Based on the proposed procedure, optimal solutions of single and multiple disc-type MR brakes featuring different types of MR fluid are achieved. From the results, the most effective MR brake for the middle-sized passenger car is identified and some discussions on the performance improvement of the optimized MR brake are described

  11. Compression Strength Testing for Automotive Brake Pads Used in Earthquake Energy Dampers

    Directory of Open Access Journals (Sweden)

    Dragoş Voiculescu

    2010-01-01

    Full Text Available In order to calibrate a friction damper which uses automotive brake pads it is necessary to determine the compression behaviour of the friction material. This paper summarizes the experimental results obtained for a set of automotive brake pads made in Romania. These results are useful in order to determine the slip load level in a seismic energy dissipation mechanism which uses this type of friction pads. The paper presents the experimental set up and the compression behaviour curves obtained for a set of four commercial brake pads. The testing was performed by the author as a part of his research work, using a hydraulic compression press.

  12. Optimal design of a disc-type MR brake for middle-sized motorcycle

    Science.gov (United States)

    Nguyen, Quoc-Hung; Jeon, Juncheol; Choi, Seung-Bok

    2011-03-01

    This research work focuses on optimal design of a disc-type magneto-rheological (MR) brake that can replace a conventional hydraulic brake (CHB) of middle-sized motorcycles. Firstly, a MR brake configuration is proposed considering the available space and the simplicity to replace a CHB by the proposed MR brake. An optimal design of the proposed MR brake is then performed considering the required braking torque, operating temperature, mass and size of the brake. In order to perform the optimization of the brake, the braking torque of the brake is analyzed based on Herschel-Bulkley rheological model of MR fluid. The constrain on operating temperature of the MR brake is determined by considering the steady temperature of the brake when the motorcycle is cruising and the temperature increase during a braking process. An optimization procedure based on finite element analysis integrated with an optimization tool is employed to obtain optimal geometric dimensions of the MR brake. Optimal solution of the MR brake is then presented and simulated performance of the optimized brake is shown with remarkable discussions.

  13. Advanced Emergency Braking Controller Design for Pedestrian Protection Oriented Automotive Collision Avoidance System

    OpenAIRE

    Guo Lie; Ren Zejian; Ge Pingshu; Chang Jing

    2014-01-01

    Automotive collision avoidance system, which aims to enhance the active safety of the vehicle, has become a hot research topic in recent years. However, most of the current systems ignore the active protection of pedestrian and other vulnerable groups in the transportation system. An advanced emergency braking control system is studied by taking into account the pedestrians and the vehicles. Three typical braking scenarios are defined and the safety situations are assessed by comparing the cu...

  14. Experimental characterization and numerical modelling of the squeal noise generated by railway disc brakes

    OpenAIRE

    CHIELLO,O; LORANG,X; Cordier, JF; MARGIOCCHI,F

    2007-01-01

    The squeal noise generated by railway disk brakes is an everyday source of discomfort for the passengers both inside and outside the trains in stations. The development of silent brake components is needed but beforehand requires a better characterisation and understanding of the phenomenon. This is the aim of the experimental and theoretical investigations performed on high power disc brakes in the framework of the CRISFIS project and presented in this paper. The first part is concerned with...

  15. Casting of Brake Disc and Impeller from Aluminium Scrap Using Silica Sand

    OpenAIRE

    Oladeji A. OGUNWOLE; Oluwafemi A. OLUGBOJI; Matthew S. ABOLARIN

    2007-01-01

    The impeller blade and the brake disc were produced using sand casting method. Wooden patterns of the two castings were constructed incorporating the necessary allowances. Green and moulding technique utilizing locally available materials were used for preparing the moulds. Aluminium scraps were used as the casting material. Melting of the Aluminium scraps was obtained using a crucible furnace and finally pouring the molten metal into the sand mould to obtain the impeller and the brake disc.A...

  16. Modeling of automotive drum brakes for squeal and parameter sensitivity analysis

    Science.gov (United States)

    Huang, Jinchun; Krousgrill, Charles M.; Bajaj, Anil K.

    2006-01-01

    Many fundamental studies have been conducted to explain the occurrence of squeal in disc and drum brake systems. The elimination of brake squeal, however, still remains a challenging area of research. Here, a numerical modeling approach is developed for investigating the onset of squeal in a drum brake system. The brake system model is based on the modal information extracted from finite element models for individual brake components. The component models of drum and shoes are coupled by the shoe lining material which is modeled as springs located at the centroids of discretized drum and shoe interface elements. The developed multi degree of freedom coupled brake system model is a linear non-self-adjoint system. Its vibrational characteristics are determined by a complex eigenvalue analysis. The study shows that both the frequency separation between two system modes due to static coupling and their associated mode shapes play an important role in mode merging. Mode merging and veering are identified as two important features of modes exhibiting strong interactions, and those modes are likely candidates that lead to coupled-mode instability. Techniques are developed for a parameter sensitivity analysis with respect to lining stiffness and the stiffness of the brake actuation system. The influence of lining friction coefficient on the propensity to squeal is also discussed.

  17. Casting of Brake Disc and Impeller from Aluminium Scrap Using Silica Sand

    Directory of Open Access Journals (Sweden)

    Oladeji A. OGUNWOLE

    2007-01-01

    Full Text Available The impeller blade and the brake disc were produced using sand casting method. Wooden patterns of the two castings were constructed incorporating the necessary allowances. Green and moulding technique utilizing locally available materials were used for preparing the moulds. Aluminium scraps were used as the casting material. Melting of the Aluminium scraps was obtained using a crucible furnace and finally pouring the molten metal into the sand mould to obtain the impeller and the brake disc.After fettling and cleaning, the two casting were found to be good. The casting yield was found to be 73.59% for the impeller blade and 85.1% for the brake disc which indicate that sound casting was achieved.

  18. Development of a net shape manufacturing method for ventilated brake discs in single piece design

    Energy Technology Data Exchange (ETDEWEB)

    Zuber, Ch.; Heidenreich, B. [German Aerospace Center (DLR) Institute of Structures and Design, Pfaffenwaldring 38-40, 70569, Stuttgart (Germany)

    2006-04-15

    Carbon fibre reinforced ceramic matrix composites (CMC), originally developed for lightweight heat shields of spacecraft, are used for high performance brake discs in sports cars from different manufacturers. In contrast to the CMC materials for space applications, based on woven fabrics and costly manufacturing methods, these low cost friction materials are produced by liquid silicon infiltration of porous Carbon/Carbon (C/C) preforms, based on short fibre reinforced CFRP green bodies manufactured via warm press technique. In this work, different manufacturing methods for ventilated CMC brake discs are compared to each other, and the development of a new technology for the manufacture of single piece C/C-SiC brake discs in net shape technique is presented. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  19. Stability and Transient Analysis in the Modelling of Railway Disc Brake Squeal

    OpenAIRE

    LORANG, X; CHIELLO, O

    2008-01-01

    The paper deals with friction induced vibrations and especially with railway disc brake squeal. The first part of the paper is devoted to the strategy used to model the general problem of self-excited vibrations of a rotating disc in frictional contact with two pads. Unilateral contact conditions with Coulomb friction and constant friction coefficient are considered. In order to predict the occurrence of self-excited vibrations, a classical stability analysis is performed, which consists on ...

  20. Automotive Brake Materials: Characterization of Wear Products and Relevant Mechanisms at High Temperature

    OpenAIRE

    Verma, Piyush Chandra

    2016-01-01

    Wear is an ubiquitous phenomenon affecting an extremely wide number of technological system, often determining their premature failure. In this regard, wear and friction behavior of friction materials and the characterization of wear debris from brake disc system is an important step to understand the dominant wear mechanisms active in a given tribological system, in order to improve its performances and to increase the expected lifetime. In the thesis, four tribological task has been perform...

  1. Toxicity and mutagenicity of low-metallic automotive brake pad materials.

    Science.gov (United States)

    Malachova, Katerina; Kukutschova, Jana; Rybkova, Zuzana; Sezimova, Hana; Placha, Daniela; Cabanova, Kristina; Filip, Peter

    2016-09-01

    Organic friction materials are standardly used in brakes of small planes, railroad vehicles, trucks and passenger cars. The growing transportation sector requires a better understanding of the negative impact related to the release of potentially hazardous materials into the environment. This includes brakes which can release enormous quantities of wear particulates. This paper addresses in vitro detection of toxic and mutagenic potency of one model and two commercially available low-metallic automotive brake pads used in passenger cars sold in the EU market. The model pad made in the laboratory was also subjected to a standardized brake dynamometer test and the generated non-airborne wear particles were also investigated. Qualitative "organic composition" was determined by GC/MS screening of dichloromethane extracts. Acute toxicity and mutagenicity of four investigated sample types were assessed in vitro by bioluminescence assay using marine bacteria Vibrio fischeri and by two bacterial bioassays i) Ames test on Salmonella typhimurium His(-) and ii) SOS Chromotest using Escherichia coli PQ37 strain. Screening of organic composition revealed a high variety of organic compounds present in the initial brake pads and also in the generated non-airborne wear debris. Several detected compounds are classified by IARC as possibly carcinogenic to humans, e. g. benzene derivatives. Acute toxicity bioassay revealed a response of bacterial cells after exposure to all samples used. Phenolic resin and wear debris were found to be acutely toxic; however in term of mutagenicity the response was negative. All non-friction exposed brake pad samples (a model pad and two commercial pad samples) were mutagenic with metabolic activation in vitro. PMID:27179608

  2. Thermomechanical behavior of dry contacts in disc brake rotor with a grey cast iron composition

    Directory of Open Access Journals (Sweden)

    Belhocine Ali

    2013-01-01

    Full Text Available The main purpose of this study is to analysis the thermomechanical behavior of the dry contact between the brake disc and pads during the braking phase. The simulation strategy is based on the calculation code ANSYS11. The modeling of transient temperature in the disk is actually used to identify the factor of geometric design of the disk to install the ventilation system in vehicles. The thermal-structural analysis is then used coupling to determine the deformation established and the Von Mises stresses in the disk, the contact pressure distribution in pads. The results are satisfactory compared to those found in the literature.

  3. Mechanical testing and modelling of carbon-carbon composites for aircraft disc brakes

    Science.gov (United States)

    Bradley, Luke R.

    The objective of this study is to improve the understanding of the stress distributions and failure mechanisms experienced by carbon-carbon composite aircraft brake discs using finite element (FE) analyses. The project has been carried out in association with Dunlop Aerospace as an EPSRC CASE studentship. It therefore focuses on the carbon-carbon composite brake disc material produced by Dunlop Aerospace, although it is envisaged that the approach will have broader applications for modelling and mechanical testing of carbon-carbon composites in general. The disc brake material is a laminated carbon-carbon composite comprised of poly(acrylonitrile) (PAN) derived carbon fibres in a chemical vapour infiltration (CVI) deposited matrix, in which the reinforcement is present in both continuous fibre and chopped fibre forms. To pave the way for the finite element analysis, a comprehensive study of the mechanical properties of the carbon-carbon composite material was carried out. This focused largely, but not entirely, on model composite materials formulated using structural elements of the disc brake material. The strengths and moduli of these materials were measured in tension, compression and shear in several orientations. It was found that the stress-strain behaviour of the materials were linear in directions where there was some continuous fibre reinforcement, but non-linear when this was not the case. In all orientations, some degree of non-linearity was observed in the shear stress-strain response of the materials. However, this non-linearity was generally not large enough to pose a problem for the estimation of elastic moduli. Evidence was found for negative Poisson's ratio behaviour in some orientations of the material in tension. Additionally, the through-thickness properties of the composite, including interlaminar shear strength, were shown to be positively related to bulk density. The in-plane properties were mostly unrelated to bulk density over the range of

  4. Fundamentals of automotive and engine technology standard drives, hybrid drives, brakes, safety systems

    CERN Document Server

    2014-01-01

    Hybrid drives and the operation of hybrid vehicles are characteristic of contemporary automotive technology. Together with the electronic driver assistant systems, hybrid technology is of the greatest importance and both cannot be ignored by today’s car drivers. This technical reference book provides the reader with a firsthand comprehensive description of significant components of automotive technology. All texts are complemented by numerous detailed illustrations. Contents History of the automobile.- History of the Diesel engine.- Areas of use for Diesel engines.- Basic principles of the Diesel engine.- Basic principles of Diesel fuel-injection.- Basic principles of the gasoline engine.- Inductive ignition system.- Transmissions for motor vehicles.- Motor vehicle safety.- Basic principles of vehicle dynamics.- Car braking systems.- Vehicle electrical systems.- Overview of electrical and electronic systems in the vehicle.- Control of gasoline engines.- Control of Diesel engines.- Lighting technology.- Elec...

  5. Optimal design of disc-type magneto-rheological brake for mid-sized motorcycle: experimental evaluation

    Science.gov (United States)

    Sohn, Jung Woo; Jeon, Juncheol; Nguyen, Quoc Hung; Choi, Seung-Bok

    2015-08-01

    In this paper, a disc-type magneto-rheological (MR) brake is designed for a mid-sized motorcycle and its performance is experimentally evaluated. The proposed MR brake consists of an outer housing, a rotating disc immersed in MR fluid, and a copper wire coiled around a bobbin to generate a magnetic field. The structural configuration of the MR brake is first presented with consideration of the installation space for the conventional hydraulic brake of a mid-sized motorcycle. The design parameters of the proposed MR brake are optimized to satisfy design requirements such as the braking torque, total mass of the MR brake, and cruising temperature caused by the magnetic-field friction of the MR fluid. In the optimization procedure, the braking torque is calculated based on the Herschel-Bulkley rheological model, which predicts MR fluid behavior well at high shear rate. An optimization tool based on finite element analysis is used to obtain the optimized dimensions of the MR brake. After manufacturing the MR brake, mechanical performances regarding the response time, braking torque and cruising temperature are experimentally evaluated.

  6. MR-fluid yield surface determination in disc-type MR rotary brakes

    International Nuclear Information System (INIS)

    Magneto-rheological (MR) fluids are currently attracting a great deal of attention because of their unique rheological behavior. Many devices have been designed using MR fluids, and of potential interest here are disc-type MR rotary brakes. The plug flow region in MR devices is defined as the region where the fluid is not flowing. The plug flow region plays an important role in design and analysis of MR devices. In MR dampers, the damping coefficient is a function of the plug thickness. In MR valves, the plug thickness is used to control the flow rate through, and the pressure drop across, the MR valve. A MR clutch is performing at the highest efficiency when the entire MR gap is the plug region. For an MR rotary brake, the highest restraining torque is obtained when the entire gap is the plug region as far as there are no wall slip effects. In this paper, using the Bercovier and Engelman constitutive model, the MR fluid flow in disc-type MR brakes is modeled to determine the plug flow region. The resulting system of equations is solved numerically. It is shown that the existence of a plug flow region in the brake will affect the control torque ratio. Better estimation of the plug flow region results in better estimation of the viscous torque

  7. Automotive airborne brake wear debris nanoparticles and cytokinesis-block micronucleus assay in peripheral blood lymphocytes: A pilot study.

    Science.gov (United States)

    Kazimirova, Alena; Peikertova, Pavlina; Barancokova, Magdalena; Staruchova, Marta; Tulinska, Jana; Vaculik, Miroslav; Vavra, Ivo; Kukutschova, Jana; Filip, Peter; Dusinska, Maria

    2016-07-01

    Motor vehicle exhaust and non-exhaust processes play a significant role in environmental pollution, as they are a source of the finest particulate matter. Emissions from non-exhaust processes include wear-products of brakes, tires, automotive hardware, road surface, and traffic signs, but still are paid little attention to. Automotive friction composites for brake pads are composite materials which may consist of potentially hazardous materials and there is a lack of information regarding the potential influence of the brake wear debris (BWD) on the environment, especially on human health. Thus, we focused our study on the genotoxicity of the airborne fraction of BWD using a brake pad model representing an average low-metallic formulation available in the EU market. BWD was generated in the laboratory by a full-scale brake dynamometer and characterized by Raman microspectroscopy, scanning electron microscopy, and transmission electron microscopy showing that it contains nano-sized crystalline metal-based particles. Genotoxicity tested in human lymphocytes in different testing conditions showed an increase in frequencies of micronucleated binucleated cells (MNBNCs) exposed for 48h to BWD nanoparticles (NPs) (with 10% of foetal calf serum in culture medium) compared with lymphocytes exposed to medium alone, statistically significant only at the concentration 3µg/cm(2) (p=0.032). PMID:27131798

  8. A method to achieve comparable thermal states of car brakes during braking on the road and on a high-speed roll-stand

    Science.gov (United States)

    Wolff, Andrzej

    2010-01-01

    The temperature of a brake friction surface influences significantly the braking effectiveness. The paper describes a heat transfer process in car brakes. Using a developed program of finite element method, the temperature distributions in brake rotors (disc and drum brake) of a light truck have been calculated. As a preliminary consistency criterion of the brake thermal state in road and roll-stand braking conditions, a balance of the energy cumulated in the brake rotor has been taken into account. As the most reliable consistency criterion an equality of average temperatures of the friction surface has been assumed. The presented method allows to achieve on a roll-stand the analogical thermal states of automotive brakes, which are observed during braking in road conditions. Basing on this method, it is possible to calculate the braking time and force for a high-speed roll-stand. In contrast to the previous papers of the author, new calculation results have been presented.

  9. Two-stage actuation system using DC motors and piezoelectric actuators for controllable industrial and automotive brakes and clutches

    Science.gov (United States)

    Neelakantan, Vijay A.; Washington, Gregory N.; Bucknor, Norman K.

    2005-05-01

    High bandwidth actuation systems that are capable of simultaneously producing relatively large forces and displacements are required for use in automobiles and other industrial applications. Conventional hydraulic actuation mechanisms used in automotive brakes and clutches are complex, inefficient and have poor control robustness. These lead to reduced fuel economy, controllability issues and other disadvantages. This paper involves the design, development, testing and control of a two-stage hybrid actuation mechanism by combining classical actuators like DC motors and advanced smart material actuators like piezoelectric actuators. The paper also discusses the development of a robust control methodology using the Internal Model Control (IMC) principle and emphasizes the robustness property of this control methodology by comparing and studying simulation and experimental results.

  10. On Airborne Nano/Micro-Sized Particles Released from Low-Metallic Automotive Brakes

    Czech Academy of Sciences Publication Activity Database

    Kukutschová, J.; Moravec, Pavel; Tomášek, V.; Matějka, V.; Smolík, Jiří; Schwarz, Jaroslav; Seidlerová, J.; Šafářová, K.; Filip, P.

    2011-01-01

    Roč. 159, č. 4 (2011), s. 998-1006. ISSN 0269-7491 Institutional research plan: CEZ:AV0Z40720504 Keywords : brake wear debris * nano particles * oxidative wear Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.746, year: 2011

  11. Braking down an accreting protostar: disc-locking, disc winds, stellar winds, X-winds and Magnetospheric Ejecta

    CERN Document Server

    Ferreira, Jonathan

    2013-01-01

    Classical T Tauri stars are low mass young forming stars that are surrounded by a circumstellar accretion disc from which they gain mass. Despite this accretion and their own contraction that should both lead to their spin up, these stars seem to conserve instead an almost constant rotational period as long as the disc is maintained. Several scenarios have been proposed in the literature in order to explain this puzzling "disc-locking" situation: either deposition in the disc of the stellar angular momentum by the stellar magnetosphere or its ejection through winds, providing thereby an explanation of jets from Young Stellar Objects. In this lecture, these various mechanisms will be critically detailed, from the physics of the star-disc interaction to the launching of self-confined jets (disc winds, stellar winds, X-winds, conical winds). It will be shown that no simple model can account alone for the whole bulk of observational data and that "disc locking" requires a combination of some of them.

  12. Research on tribological characteristics between Al-MMC brake disc and friction material; Untersuchung der tribologischen Eigenschaften von Al-MMC-Bremsscheiben und Reibmaterial

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, K.; Kawasaki, K.

    2000-07-01

    Recently weight reduction of automobiles has become more important because of higher demands for reducing CO{sub 2} in the atmosphere. Especially weight reduction in body and chassis are considered because of their effect. In this situation alternating the conventional cast iron brake disc to AL-MMC has been considered by many brake and automobile manufacturers as a way of saving weight. In the last five years much research about the making process or thermal property of AL-MMC brake disc has been presented. However, one of the most important problems in applying AL-MMC brake disc to automobiles is the difference in frictional characteristics from cast iron disks. So, we have researched the tribological characteristics between AL-MMC brake disc and friction material. From this research the technique of friction material that is suitable for AL-MMC brake disc has become clear. In this presentation, I will introduce the key points of this technology. (orig.) [German] In letzter Zeit wird das Thema Gewichtsreduzierung von Automobilen immer wichtiger, weil immer haeufiger eine Reduzierung von CO{sub 2} in der Atmosphaere gefordert wird. Von einer Gewichtsreduzierung an Karosserie und Fahrwerk verspricht man sich eine besonders grosse Wirkung. Deshalb erwaegen viele Automobilhersteller, die herkoemmlichen Bremsscheiben aus Gusseisen durch solche aus Aluminium-MMC zu ersetzen. In den letzten fuenf Jahren wurden zahlreiche Forschungsarbeiten ueber den Herstellungsprozess und die thermischen Eigenschaften von Aluminium-MMC-Bremsscheiben praesentiert. Eines der groessten Probleme bei der Verwendung von Aluminium-MMC-Bremsscheiben im Automobilbau liegt darin, dass sich ihre Reibungseigenschaften von denen der Gusseisenscheiben stark unterscheiden. Wir haben die tribologischen Eigenschaften von Aluminium-MMC-Bremsscheiben und Reibmaterial daraufhin untersucht. Durch diese Forschungsarbeiten haben wir Klarheit ueber die Eigenschaften von Reibmaterialien gewonnen, die fuer

  13. Energy thrift and improved performance achieved through novel railway brake discs

    International Nuclear Information System (INIS)

    A disc with radial vanes and circumferential pillars proves to be successful in operation and achieves energy efficiency improvements compared with those of traditional design. Cooling characteristics of this novel design are practically identical to the disc with tangential vanes but the equivalent aerodynamic (air pumping) losses are approximately 50% less. It is shown that these reductions in pumping losses can lead to substantial energy savings in train operations. When developing new designs and/or comparing different railway disc designs, the proposed disc cooling to aerodynamic efficiency ratio (ηv) was found to be a very useful parameter to assess. This 'efficiency ratio' - a ratio of convective power dissipation to aerodynamic power losses can help in achieving adequate balance of cooling efficiency and aerodynamic losses to suit particular application. The use of CFD is of enormous benefit in generating discs that fulfil these demanding requirements, with the spin rig being exceptionally useful for experimental work

  14. Simulation of the Friction Temperature Field for Disc Brake%盘式制动器摩擦温度场的数值模拟

    Institute of Scientific and Technical Information of China (English)

    刘莹; 周启兴

    2012-01-01

    采用COMSOL Multiphysics模拟盘式制动器制动过程的二维瞬态温度场,研究了割动盘和摩擦片的温度分布情况以及它们的热物性参数对摩擦副温度场的影响.结果表明:盘式制动器在制动过程中的高温时刻,高温处在沿盘转动方向与摩擦片滑出的区域;制动盘表面温度从高温度区域沿制动盘转动方向递减,摩擦片表面温度沿盘转动反方向递减;制动盘和摩擦片的径向温度最大值出现在摩擦区域的中部位置,而外径和内径处温度较低,轴向方向都由摩擦面表层向内层方向递减;增大制动盘或摩擦片的某一热物性参数均可降低摩擦副表面最大温度值,但制动盘相对摩擦片,其导热系数、比热容和密度对摩擦副温度值的影响要大得多,研究内容可为制动器的结构设计及材料的选择提供参考.%The three-dimensional transient temperature field for disc brake were simulated using software COM-SOL Multiphysics, the situation of temperature distribution for friction pairs device in the braking process and the effect of material thermal parameters on its temperature field were investigated. The results showed that at the high-temperature moment of the braking process of the disc brake, the high temperature place was located on the area of sliding out with the friction plate along the disk rotates direction; the surface temperature of brake disc decreased from the high temperature zone along the direction of the brake disc rotation; the surface temperature of friction plate decreased along the opposite direction of the brake disc rotation; the maximum radial temperature of the brake disc and friction plate in the braking process was located on the central part of the friction zone,the temperature of the outside radius and inside radius was lower, the temperature of the axial direction decreased from the friction surface layer to the inner layer direction; it can reduce the maximum

  15. 基于ABAQUS的列车盘型制动的温度场分析%Analysis on Temperature Field of Train Disc Brake Based on ABAQUS

    Institute of Scientific and Technical Information of China (English)

    王国顺

    2013-01-01

    The influences of rotating speed and the friction radius,height and shape,and place form of braking block on the temperature field of the brake disc and brake block were simulated by the finite element analysis software of ABAQUS.The results show that with the increase of crank's rotating speed,the brake disc and brake block's temperatures are increased,and the distribution of high temperature region is changed from stripe to speckle.The reason is that with the increase of revolving speed,the vibration between the friction pairs is aggravated,and the local contact was produced to cause the high temperature.There is an inflection point of temperature in the thickness direction of brake disc,with the increase of the distance to the friction surface,the temperature is declined rapidly,and in the distance of 3 ~ 6 mm to the friction surface,the change of temperature is not obvious.The change of brake block height or shape has no obvious influence on the brake disc temperature,while the placement form of the triangle brake block has influence on temperature distribution.%应用有限元软件ABAQUS,模拟转动速度和制动块摩擦半径、高度以及形状与放置形式等对制动盘和制动块温度场的影响.得出如下结论:随转速的提高,制动盘和制动块温度升高,高温区的分布由条带状向斑点状转变,原因在于随转速增加,摩擦副间的振动程度加剧,从而造成局部接触产生高温.制动盘温度在厚度方向上存在一个拐点,随深度增加,制动盘温度快速下降,在距摩擦表面3~6mm时,温度变化不明显.制动块高度、形状改变,对制动盘温度无明显影响,而三角形制动块的放置形式对制动块温度分布有影响.

  16. Effects of potassium titanate fiber on the wear of automotive brake linings

    Science.gov (United States)

    Halberstadt, M. L.; Mansfield, J. A.; Rhee, S. K.

    1977-01-01

    Asbestos reinforcing fiber in an automotive friction material was replaced by an experimental ingredient having better thermal stability, and the effects on wear and friction were studied. A friction materials test machine (SAE J661a) was used to determine friction and wear, under constant energy output conditions, as a function of temperature between 121 and 343 C (250 and 650 F). When potassium titanate fiber replaced one half of the asbestos in a standard commercial lining, with a 40 percent upward adjustment of phenolic resin content, wear above 204 C (400 F) was improved by 40% and friction by 30%. Tests on a full-scale inertial dynamometer supported the findings of the sample dynamometer tests. It was demonstrated that the potassium titanate fiber contributes directly to the improvement in wear and friction.

  17. 浅析逆向注油排气法在汽车液压制动系统中的应用%On the Application of Reverse Oiling and Exhaust Method in Automotive Hydraulic Braking System

    Institute of Scientific and Technical Information of China (English)

    曹志维

    2014-01-01

    Automotive hydraulic braking system is the automotive braking device by using the brake fluid as the transmission media to make the wheel brakes work. The hydraulic braking system has the advantages of smooth braking and high sensitivity. Once the hydraulic braking system occur air resistance, it will cause braking weak, the braking force reducing and other failure, and reduce the braking performance of wheel brakes, so that will directly affects the car's braking performance and safety. This paper introduces an operation method overturning the traditional methods:reverse oiling and exhaust method. This method is simple and practical, and can greatly improve the maintenance efficiency.%汽车液压式制动系统是利用制动油液作为传力介质使车轮制动器工作的汽车制动装置,液压式制动系统具有制动平稳、制动灵敏度高等优点。而当液压制动系统一旦发生气阻时就会导致制动发软、制动力减小等故障,使车轮制动器的制动效能下降,直接影响汽车的制动性能和安全性。文章介绍一种颠覆传统操作方法:逆向注油排气法,这种方法简单实用,极大地提高了维修效率。

  18. 高速列车制动盘泵风效应分析%Air-pumping effect analysis for brake disc of high-speed train

    Institute of Scientific and Technical Information of China (English)

    左建勇; 罗卓军

    2014-01-01

    为研究列车运行过程中制动盘泵风特性,建立了列车、轨道、制动盘及其附近空气流场的有限元模型,采用动网格流固耦合仿真方法,计算了制动盘泵风功耗,分析了制动盘泵风对牵引功率的影响。以运行速度为300 km·h-1的4动4拖8辆编组列车为例,进行了制动盘泵风效应的仿真与对比分析。分析结果表明:制动盘泵风功耗与列车运行速度成正比,每辆车泵风功耗为54~70 kW,泵风阻力矩与制动盘安装位置无关,主要受制动盘转动速度影响;随列车运行速度的提高,制动盘泵风功耗占比略有下降,当列车运行速度由200 km·h-1提高为400 km·h-1时,制动盘泵风功耗占比由12%降低为8%;封堵制动盘进风口可以降低泵风功耗的影响,当列车运行速度为300 km·h-1时,封堵制动盘进风口后,列车制动盘泵风功耗由原来的489 kW降低为68 kW,泵风功耗占基本阻力功耗的比例由原来的9.0%降低为1.3%,改善效果显著。可见,从泵风功耗角度探索优化高速列车制动盘散热筋结构具有较大的现实意义。%To study the air-pumping characteristics of brake disc during train operation,the finite element models including vehicle,rail,brake disc and related air flow field were put forward. The air-pumping power consumption of brake disc was calculated,and its effect on traction power was analyzed by using dynamic grid and flow-solid conjugation simulation method.Taking a 8-unit high-speed train composed of 4 motor cars and 4 trailers running at 300 km · h-1 as an example,the air-pumping effect of brake disc was simulated and compared.Simulation result indicates that the air-pumping power consumption of brake disc is in proportion to train running speed.The air-pumping power consumption of each car is about 54-70 kW.The air-pumping torque,independent of installation position of brake disc,is mainly influenced by the

  19. Cubic Silicon Carbide: a promising material for automotive application

    OpenAIRE

    Attolini, Giovanni; Bosi, Matteo; Rossi, Francesca; Watts, Bernard Enrico; Salviati, Giancarlo

    2008-01-01

    carbide is a material that possesses properties that make it desirable in electronic, structural and sensor applications. As a wide band gap semiconductor it can be used in high power, high temperature electronics and harsh environments. Its hardness, wear resistance, chemical inertness, and thermal conductivity find uses ranging from disc brakes to micron scale sensors and actuators. The automotive industry faces some important challenges since it has obligations to manufacture safe, clean, ...

  20. Simulation and analysis of vehicle stability based on ADAMS/CAR differential brake

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To improve the braking safety of automobiles, the author studied the effect of differential brake on the stabilities. To analyze the mechanical characteristics of differential brake, automotive subsystem models were built by applying ADAMS/CAR, and automotive mechanics simulation model was built by setting the main subsystems such as body, engine and brake. The simulation model studied the distribution mode of three kinds of differential brake, and beeline braking stability and turning braking stability wer...

  1. Experimental study using infrared thermography on the convective heat transfer of a TGV brake disc in the actual environment

    Science.gov (United States)

    Siroux, Monica; Harmand, Souad; Desmet, Bernard

    2002-07-01

    We present an experimental identification of the local and mean Nusselt number from a rotating TGV brake disk model in the actual environment and exposed to an air flow parallel to the disk surface. This method is based on the use of a heated thermally thick disk combined with the technique of temperature measurement by infrared thermography. The local and mean convective heat transfer coefficient from the disk surface is identified by solving the steady state heat equation by a finite difference method using the experimental temperature distribution as boundary conditions. The experimental setup is constituted of a model disk with all the representative parts of the actual TGV brake system. The disk and its actual environment are inside a wind tunnel test section, so that the rotational disk speed and the air flow velocity can be varied. Tests were carried out for rotational speeds w between 325 and 2000 rpm (rotational Reynolds number Re between 88,500 and 545,000), and for an air flow velocity U ranging between 0 and 12 m(DOT)s-1 (air flow Reynolds number Re0 between 0 and 153,000).

  2. Design of the brake disc shape and position error detecting method%汽车制动盘形位公差检测方法与方案设计

    Institute of Scientific and Technical Information of China (English)

    王燕涛; 朱彬; 姜风国; 李秦阳

    2013-01-01

    With the actual demand of the automobile brake disc shape and position error measurement ,a detection scheme based on the contacting measuring type was proposed .Different detection methods for the brake disc were analyzed .And the digital de-tection theoretical basis was established .At the basis of the detection process ,the overall mechanical scheme supporting the meas-uring actions was given.Namely,the brake disc clamping device ,the rotating device,the positioning supporting device and the sensor supporting device was included .This designing scheme can effectively support the real-time online testing requirements with the brake disc shape and position error data .%针对汽车制动盘形位公差检测的实际需求,提出了一种基于接触式测量原理的汽车制动盘形位公差检测方案。分析了制动盘不同形位公差的检测方法,为实现由手工检测向计算机数字化检测方式的转变建立理论分析基础。在检测流程分析的基础上,给出了实现制动盘检测的机械方案整体构成,即制动盘固定夹持机构、旋转机构、定位支撑机构和传感器支持机构,可以有效支持制动盘形位公差数据的实时在线检测要求。

  3. Brake assembly including torque monitor

    International Nuclear Information System (INIS)

    This patent describes a brake assembly for selectively braking rotation of an input shaft extending from a control rod drive having a longitudinal centerline axis, the shaft being rotatable for selectively inserting and withdrawing a control rod in a nuclear reactor vessel. It comprises a stationary base; an annular bearing mounted to the base; a brake mounted to the bearing; a backing plate mounted to the bearing; a first braking pad fixedly joined to the backing plate; a rotor disc fixedly connected to the input shaft and disposed adjacent to the first pad; a second braking pad disposed adjacent to the rotor disc; and means for selectively clamping the first and second pads against the rotor disc for braking the input shaft; means for torsionally restraining the brake including: a pin extending outwardly from the backing plate toward the base; and a spring extending from the base to the pin and generally perpendicular to the centerline axis; and means for monitoring the angle for monitoring braking torque capability of the brake

  4. 带式输送机盘式制动器转速测量研究%Study on measurement of rotational speed of disc brakes for belt conveyors

    Institute of Scientific and Technical Information of China (English)

    吴向凡; 尹作振

    2012-01-01

    针对带式输送机盘式制动器转速测量误差较大及跳变问题,提出了一种有效的转速测量方法,根据该方法对盘式制动器转速测量系统进行了设计,并开展了相关试验研究。结果表明,该测速方法可有效提高盘式制动器超速控制精度和稳定性,满足带式输送机的速度控制要求。%In view of large measurement error and transient change of rotational speed of the disc brake for the belt conveyor, an effective measurement method for rotational speed was proposed. According to the method, a system of measuring the rotational speed of the disc brake was designed, and related test study was conducted. The results showed that the measurement method could effectively improve the precision and stability of overspeed control of the disc brake as well as satisfy the speed control requirements of the belt conveyor.

  5. 机车制动机现场培训考试系统的研究%Research on the On-site Training Exam System of Automotive Braking Machine

    Institute of Scientific and Technical Information of China (English)

    张玲

    2015-01-01

    The on-site training exam system of automotive braking machine was devised and developed with the pneumatic technology on the basis of liquid mechanics theory aimed at the problems such as short time of cultivation for the locomotive drivers, insufficient experience, and unskilled degree of controlling the locomotive, low accuracy to the estimation of the phenomenon. It was applied in the training of steward and achieved distinct effect, enhanced the level for steward to operate braking machine and judge the train braking pipe accurately.%针对目前普遍存在机车司机培养时间短、 经验不足, 对机车操纵的熟练程度及对现象判断的准确性不高的问题, 采用气动技术、 依据流体力学理论, 设计开发了机车制动机现场培训考试系统. 经过在乘务员培训中的应用, 取得明显的效果, 提高了乘务员的制动机操作水平和对列车管判断的准确性.

  6. Simulation and analysis of vehicle stability based on ADAMS/CAR differential brake

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To improve the braking safety of automobiles, the author studied the effect of differential brake on the stabilities. To analyze the mechanical characteristics of differential brake, automotive subsystem models were built by applying ADAMS/CAR, and automotive mechanics simulation model was built by setting the main subsystems such as body, engine and brake. The simulation model studied the distribution mode of three kinds of differential brake, and beeline braking stability and turning braking stability were simulated. It shows that differential brake can amend turning shortage of automobile brake and improve its braking stability, but the effect of automobile mass on its braking stability is great. So the distribution mode of braking force and the effect of mass change should be considered while differential brake is applied.

  7. Research on the Feasibility of Application of ABS in Hydraulic Disc Brake%ABS在液压盘式刹车中应用的可行性研究

    Institute of Scientific and Technical Information of China (English)

    石固欧; 刘威

    2013-01-01

    The anti-lock braking system (ABS) of automobiles has such advantages as slippage and lock prevention,relatively short distance of braking and reduction of tyre wear.Therefore,the ABS control strategy was introduced to the design of the hydraulic system of drilling and workover rigs.The neotype hydraulic control system of hydraulic disc brake with both manual and automatic operation modes was built,which could achieve ABS control strategy.A comparative braking dynamic simulation analysis of the hydraulic system and running conditions with and without the ABS system was conducted.The analysis shows that selection of the proper duty cycle of the ABS system can get closer to the braking time and angle displacement without the ABS system.The better pressure regulation waveform had been obtained.Regulation of the ABS control strategy can obtain the ideal braking time and brake's braking torque.Therefore,the complex requirement of workover lifting system for operation process can be satisfied desirably.%汽车ABS防抱死刹车系统具有防滑防抱、制动相对距离短及能减轻轮胎磨损等优点.为此,将汽车ABS控制策略引入到钻(修)井机液压盘式刹车系统设计中,构建了具有手动/自动操作方式且能实现ABS控制策略的液压盘式刹车的新型液压控制系统,并对具有ABS系统与无ABS系统的盘式刹车分别进行液压系统与下入工况制动动力学仿真对比分析.分析结果表明,选择适当的ABS系统占空比,可以更接近无ABS系统刹车时间与角位移,并获得较好的压力调节波形,调整ABS控制策略可使系统获得理想的刹车时间与刹车制动力矩,从而能够较好地满足修井机起升系统作业过程的复杂要求.

  8. 汽车辅助制动系统及试验方法研究%Study on Automotive Auxiliary Braking System and Test Method

    Institute of Scientific and Technical Information of China (English)

    王勇; 张雄; 刘翰东

    2013-01-01

    The authors introduce the type and principles of the auxiliary braking types, and describe the require-ments and test methods of typeⅡand typeⅡA tests. Through simulating the ramp test, they verify the meeting of the exhaust braking and the retarder braking to the standard, and put forward the relative recommendations.%介绍辅助制动装置的类型及原理,并对Ⅱ型和ⅡA型试验的要求和试验方法进行阐述。通过模拟坡道试验,验证排气制动和缓速器对标准的满足性,并给出相应建议。

  9. Gravity brake

    Science.gov (United States)

    Lujan, Richard E.

    2001-01-01

    A mechanical gravity brake that prevents hoisted loads within a shaft from free-falling when a loss of hoisting force occurs. A loss of hoist lifting force may occur in a number of situations, for example if a hoist cable were to break, the brakes were to fail on a winch, or the hoist mechanism itself were to fail. Under normal hoisting conditions, the gravity brake of the invention is subject to an upward lifting force from the hoist and a downward pulling force from a suspended load. If the lifting force should suddenly cease, the loss of differential forces on the gravity brake in free-fall is translated to extend a set of brakes against the walls of the shaft to stop the free fall descent of the gravity brake and attached load.

  10. Automotive mechatronics automotive networking, driving stability systems, electronics

    CERN Document Server

    2015-01-01

    As the complexity of automotive vehicles increases this book presents operational and practical issues of automotive mechatronics. It is a comprehensive introduction to controlled automotive systems and provides detailed information of sensors for travel, angle, engine speed, vehicle speed, acceleration, pressure, temperature, flow, gas concentration etc. The measurement principles of the different sensor groups are explained and examples to show the measurement principles applied in different types. Contents Basics of mechatronics.- Architecture.- Electronic control unit.- Software development.- Basic principles of networking.- Automotive networking.- Bus systems.- Automotive sensors.- Sensor measuring principles.- Sensor types.- Electric actuators.- Electrohydraulic actuators.- Electronic transmission control.- Electronic transmission control unit.- Modules for transmission control.- Antilock braking system.- Traction control system.- Electronic stability program.- Automatic brake functions.- Hydraulic modu...

  11. Neutrons put the brakes on stress

    International Nuclear Information System (INIS)

    Don't you hate it when you're driving along, put your foot on the brake and feel that juddering feeling through the pedal? It happens when the disc brake rotors become distorted through normal use of the brakes. To the car manufacturing industry it's called runout, and is a multimillion dollar warranty problem each year. Not to mention a pain for drivers! Dr Maurice Ripley and Dr Oliver Kirstein from the Australian Nuclear Science and Technology Organisation (ANSTO) wanted to figure out whether runout is caused by residual stresses from the manufacturing process or by normal use of the brake, so they decided to test and compare a used and new brake disc. 'To picture what metal looks like at the atomic level, imagine spheres stacked evenly around each other in all three dimensions,' explained Kirstein. The spheres represent atoms in the metal and the structure is called a metallic lattice.' We're familiar with the idea that metal expands when it gets hot - the atoms get excited with the heat and have the energy to move further away from each other, so spaces between the atoms in the lattice get larger. 'When parts of the metal are heated up and cool down at different rates, you may end up with a distorted lattice with some parts expanded and others not,' explained Kirstein. 'This unevenness in the lattice creates residual stress.' While a bunch of methods were available to test the discs, Kirstein and Ripley picked neutrons from ANSTO's HIFAR (High Flux Australian Reactor) as their tool of choice. 'Neutrons allow us to look at the inside of the metal without damaging it,' said Kirstein. 'They can penetrate through the iron, so we were able to take measurements at a series of points at different depths through the brake disc.' Word around the car industry is that when residual stresses are relaxed through heating of the brake disc during use, the discs could potentially distort, causing the runout and that juddering feeling. But everyone was clueless as to what

  12. The development of the brake system for the Mercedes-Benz Vito; Entwicklung der Bremsanlage fuer den Vito von Mercedes-Benz

    Energy Technology Data Exchange (ETDEWEB)

    Reuter, M.; Spielmann, W.

    1996-05-01

    The new Mercedes Vito is a vehicle which was designed to meet both the requirements of tough city van operation and the sophisticated demands of private buyers seeking a car-like multi-purpose vehicle. The vehicle is fitted with disc brakes all round and, in the majority of the European markets, with ABS/ABD as standard. Its hydraulic brake system, using floating-caliper wheel brakes, is diagonally divided and equipped with a vacuum brake booster and automatic load-sensing brake pressure control. In addition to meeting the customary requirements made on van brakes, the target in development was to fulfil the higher demans made on car brakes in terms of comfort and high speed. For the first time, system development was commissioned to the brake manufacturer ITT Automotive Europe; this step followed logically from the approach adopted in the development of the brake system for the Sprinter. As a result of this approach, the scope of brake testing performed by the vehicle manufacturer was substantially reduced. Close cooperation also permitted the vehicle manufacturer to gain sufficient know-how so as to be able to control future developments in a target-oriented manner. The prerequisite for this is the existence of Detailed specifications dockets for Development and testing, including requirement profiles, test programs, test specifications and schedules. The positive results of testing prior to the approval for series production and problem-free operation during large-scale testing by customers prove that this approach can also be applied to future projects. (orig.) [Deutsch] Der neue Vito von Mercedes-Benz ist serienmaessig mit vier Scheibenbremsen und fuer die meisten europaeischen Maerkte mit ABS und ABD ausgeruestet. Zum Einsatz kommt eine diagonal aufgeteilte hydraulische Bremsanlage mit Vakuum-Hilfskraftunterstuetzung und automatisch lastabhaengiger Bremskraftaufteilung (ALB). Als Radbremsen werden an der Vorderachse Faustsattelbremsen, an der Hinterachse

  13. Experimental Identification of Brake Pad Material Properties—A Step Towards a Better Prediction of Brake Squeal

    Science.gov (United States)

    Hornig, Sylwia; Hochlenert, Daniel; von Wagner, Utz

    2010-09-01

    Automotive brake squeal is a disruptive high frequency sound radiation phenomenon generated by friction-induced self-excited vibrations of the brake system. The brake system loses its stability and starts oscillating in a limit cycle with amplitudes limited by nonlinearities, the main origin of the nonlinearities being brake lining material. In order to perform a reliable brake squeal prediction using established mathematical-mechanical models, the knowledge of the lining material properties is of great importance. The present paper deals with the experimental identification of lining material properties, expecially referring to the elastic properties. Since these strongly vary depending on the operating conditions of brake systems, it is necessary to reproduce the operating conditions during brake squeal as close as possible in experimental setups. In this context a special test rig, the test data evaluation and the experimentally determined nonlinear elastic brake lining properties are presented. Assuming these brake lining properties to be the prominent source of the nonlinearity, a nonlinear stability analysis is performed on a realistic disk brake model. The results referring to brake squeal are discussed, whereas basic phenomena known from operating experience of brake systems can be explained on the basis of this analysis.

  14. Low-impact friction materials for brake pads

    OpenAIRE

    Bonfanti, Andrea

    2016-01-01

    State-of-the-art friction materials for applications in disc brake systems are constituted by composite materials, specifically formulated to ensure proper friction and wear performances, under the sliding contact conditions of braking events. The bases of typical friction compound formulations usually include 10 to 30 different components bonded with a polymeric binder cross-linked in situ. Main requests to be fulfilled during braking are an adequate friction efficiency and enough mechanical...

  15. 汽车刹车片用铁铜基摩擦材料的研究%Study of Fe and Cu-based P/M friction materials for automotive brake pads

    Institute of Scientific and Technical Information of China (English)

    陈文革; 罗启文; 张剑; 崔婷婷

    2012-01-01

    A kind of iron-copper based fricition material for automotive brake pad was prepared by powder metallurgy technology; mixing of electrolytic copper powder with particle size of 53 -14祄 and iron, graphite, titanium, nickel, silica, aluminum oxide and vulcanized molybdenum powder, compaction forming at 450 - SSOMPa, hot pressing sintering at 1 000t and pressure of 2. 5 - 2. SMPa for 1 - 2h. The microstmcture consist of iron and copper, ceramic, carbide and additives, the density and hardness of the friction materials is 5.57 g/cm3 and 227HV, respectively. By the wear testing, the wear rate and friction factor of the friction materials is 0. 002 6 g/min and 0.45,respectively. The influence factor of the friction materials is normal presser and rotate speed, the failure mechansm is adhere wear at first and grinding compound wear mostly.%采用粉末冶金热压技术制备铁铜基刹车片材料,进行磨损试验和扫描电镜观察.结果表明:将粒度53~74 μ,m的电解Cu粉、Fe粉、石墨、Ti、Ni、SiO2、Al2O3 MoS2混合均匀,于450~550MPa的压制压力下模压成形,在1 000℃、2.5~2.8MPa压力下N2保护热压1~2h,可制备出汽车刹车片用铁铜基摩擦材料.其显微组织由粘结的基体Fe、Cu相,耐磨的陶瓷、碳化物相和一些润滑相所构成;所制备材料的密度为5.57 g/cm3,平均硬度是227HV.影响其摩擦性能的主要因素是法向压力和转速,与钢的磨损速率为0.002 6 g/min,摩擦系数0.45;磨损的失效机理是先期粘着磨损,随后转化为磨料磨损,但以磨料磨损为主.

  16. Radial brake assembly for a control rod drive

    International Nuclear Information System (INIS)

    This patent describes a brake assembly for a control rod drive for selectively preventing travel of a control rod in a nuclear reactor vessel. It comprises a shaft having a longitudinal centerline axis; means for selectively rotating the shaft in a first direction and in a second direction, opposite to the first direction; a stationary housing having a central aperture receiving the shaft; a frame fixedly joined to the housing and having a guide hole; a rotor disc fixedly connected to the shaft for rotation therewith and having at least one rotor tooth extending radially outwardly from a perimeter thereof, the rotor tooth having a locking surface and an inclined surface extending therefrom in a circumferential direction; a brake member disposed adjacent to the rotor disc perimeter and including a base, at least one braking tooth having a locking surface extending therefrom in a circumferential direction, and a plunger extending radially outwardly from the base and slidably joined to the frame through the guide hole; the rotor tooth and the braking tooth being complementary to each other; and means for selectively positioning the brake member in a deployed position abutting the rotor disc perimeter for allowing the braking tooth locking surface to contact the rotor tooth locking surface for preventing rotation of the shaft in the first direction, and in a retracted position spaced radially away from the rotor disc for allowing the rotor disc and the shaft to rotate without restraint from the brake member, the positioning means including a tubular solenoid fixedly joined to the frame and having a central bore disposed around the brake member plunger and effective for sliding the brake member plunger relative to the frame for positioning the brake member in the deployed and retracted positions

  17. Evaluation of Wear in Aftermarket Brake Pads for Enhancing Braking Performance in a Passenger Vehicle

    Directory of Open Access Journals (Sweden)

    Mohd Zaki Bahrom

    2016-08-01

    Full Text Available Nowadays, due to the high demands from the independence automotive service centers; there are many aftermarket brake pads available at spare parts shops and sold at reasonable prices. Several types of brake pads are available in the market such as semi-metallic and Non-Asbestos brake pads. The purpose of this study is to evaluate the wear of after-market brake pad performance under the normal driving conditions (highway and non-highway. Three types of aftermarket brake pads that mainly used and sold by independent service shop were selected in this study.  The data of the wear in thicknesses losses and weight percentage losses were recorded. The results show that brake pad of non- Asbestos Organic type gives the highest wear loss and create a lot of dust. For semi-metallic brake pad type, the result shows the lowest mass loss. Therefore, it is important to select the suitable type of after-market brake pads in order to get balance between cost and quality.

  18. THE INFLUENCE OF BRAKE PADS THERMAL CONDUCTIVITY ON PASSANGER CAR BRAKE SYSTEM EFFICIENCY

    Directory of Open Access Journals (Sweden)

    Predrag D Milenković

    2010-01-01

    Full Text Available In phase of vehicle braking system designing, besides of mechanical characteristics, it is also necessary to take under consideration the system's thermal features. This is because it is not enough just to achieve proper braking power, for the brake system to be effective but equally important thing is the dissipation of heat to the environment. Heat developed in the friction surfaces dissipate into the environment over the disk in one hand and through the brake linings and caliper, in the other. The striving is to make that greatest amount of heat to dissipate not threw the brake pads but threw disc. The experimental researching of heat transfer process taking place at vehicle brakes was made in the R&D Center of "Zastava automobili" car factory in order to increase the efficiency of brake system. The standard laboratory and road test procedures were used, according to factory quality regulations. The modern equipment such as thermo camera, thermo couples, torque transducers, signal amplifiers, optical speed measuring system and laptop computer were used. In this paper will be shown the part of the experimental researching, which refers to the thermal conductivity of brake pad friction linings.

  19. Brake force estimation for electromechanical vehicle brakes; Bremskraft-Rekonstruktion fuer elektromechanische Fahrzeugbremsen

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, R. [Continental Teves (Germany)

    1999-06-01

    Due to the increasing safety and comfort demands of the customer, the functionality of modern brake systems has grown continuously in the last years. However, implementation of the extended functionality in conventional brake hydraulics makes active electronic intervention necessary and therefore requires a lot of technical effort. In recent years the automotive supplier industry has started to develop brake systems which have electromechanical brake actuators generating the brake forces at the individual wheels. Electromechanically actuated wheel brakes need to be operated in a closed control loop. This paper introduces a new method to reconstruct the needed feedback value brake force from easy to measure signals. (orig.) [Deutsch] Aufgrund des gestiegenen Sicherheits- und Komfortbewusstseins der Fahrzeugkaeufer ist die Funktionsvielfalt moderner Bremssysteme in den letzten Jahren staendig gewachsen. Die Umsetzung der erweiterten Funktionalitaet mittels konventioneller Bremsenhydraulik ist jedoch durch den elektronischen, aktiven Eingriff sehr aufwendig. In den letzten Jahren hat daher die Automobilzulieferindustrie begonnen, Bremssysteme zu entwickeln, bei denen die Bremskraft an den einzelnen Raedern von elektromechanischen Bremsaktuatoren aufgebracht wird. Elektromechanisch betaetigte Radbremsen muessen im geschlossenen Regelkreis betrieben werden. Der vorliegende Beitrag, der im Rahmen einer Forschungskooperation zwischen Continental Teves und dem Institut fuer Automatisierungstechnik der TU Darmstadt entstand stellt ein Verfahren vor, mit dem die dafuer benoetigte Rueckfuehrungsgroesse `Bremskraft` aus einfach messbaren Signalen rekonstruiert werden kann. (orig.)

  20. How to play a disc brake

    OpenAIRE

    Kirillov, Oleg N.

    2007-01-01

    We consider a gyroscopic system under the action of small dissipative and non-conservative positional forces, which has its origin in the models of rotating bodies of revolution being in frictional contact. The spectrum of the unperturbed gyroscopic system forms a "spectral mesh" in the plane "frequency -gyroscopic parameter" with double semi-simple purely imaginary eigenvalues at zero value of the gyroscopic parameter. It is shown that dissipative forces lead to the splitting of the semi-sim...

  1. How to play a disc brake

    CERN Document Server

    Kirillov, Oleg N

    2007-01-01

    We consider a gyroscopic system under the action of small dissipative and non-conservative positional forces, which has its origin in the models of rotating bodies of revolution being in frictional contact. The spectrum of the unperturbed gyroscopic system forms a "spectral mesh" in the plane "frequency -gyroscopic parameter" with double semi-simple purely imaginary eigenvalues at zero value of the gyroscopic parameter. It is shown that dissipative forces lead to the splitting of the semi-simple eigenvalue with the creation of the so-called "bubble of instability" - a ring in the three-dimensional space of the gyroscopic parameter and real and imaginary parts of eigenvalues, which corresponds to complex eigenvalues. In case of full dissipation with a positive-definite damping matrix the eigenvalues of the ring have negative real parts making the bubble a latent source of instability because it can "emerge" to the region of eigenvalues with positive real parts due to action of both indefinite damping and non-c...

  2. Can non-ideal magnetohydrodynamics solve the magnetic braking catastrophe?

    CERN Document Server

    Wurster, James; Bate, Matthew R

    2015-01-01

    We investigate whether or not the low ionisation fractions in molecular cloud cores can solve the `magnetic braking catastrophe', where magnetic fields prevent the formation of circumstellar discs around young stars. We perform three-dimensional smoothed particle non-ideal magnetohydrodynamics (MHD) simulations of the gravitational collapse of one solar mass molecular cloud cores, incorporating the effects of ambipolar diffusion, Ohmic resistivity and the Hall effect alongside a self-consistent calculation of the ionisation chemistry assuming 0.1 micron grains. When including only ambipolar diffusion or Ohmic resistivity, discs do not form in the presence of strong magnetic fields, similar to the cases using ideal MHD. With the Hall effect included, disc formation depends on the direction of the magnetic field with respect to the rotation vector of the gas cloud. When the vectors are aligned, strong magnetic braking occurs and no disc is formed. When the vectors are anti-aligned, a disc with radius of 13AU ca...

  3. Use of a hydraulic brake as a source of thermal energy for the railway rolling stock

    Directory of Open Access Journals (Sweden)

    V.A.Gabrinets

    2012-12-01

    Full Text Available Introduction: In this paper the braking issues of passenger trains which have a great speed and frequent stops are examines. Problem statement: These processes are ехpensive and have big energy losses. The proposed solution to the problem: The kinetic energy of braking prosses propose to turn into thermal energy of heating fluid. For this purpose special hydraulic brake is proposed. The brake is connected with the wheel carriage pairs. The process is based on the energy dissipation in liqid when the disks with spikes rotate in it. Because the real liquid has friction and viscosity, it will be heat up, when the mechanical parts of the hydraulic brake are moved in it. The design, operating principle and characteristics of the hydraulic brake are proposed. Transmission of kinetic energy of carriage motion to brake system executed by mechanical clutches. It connected with the wheel pair and transmitting the energy the wheels rotation to hydraulic brake discs. The cylindrical rods are installed on the discs. Rods location fits the profile of the curved centrifugal pump vanes. As result, the fluid heatind prosess by rotatinge discs with rods take place also at the same time with the liquid pumping through the inner volume of brake system.Conclusions: Affordable passenger carriage braking dynamic is achieved by varying the size and number of rods. The heated liquid may be subsequently used for household needs and for heating the passenger carriage.

  4. Analysis of nanoparticles released from the car brakes

    Czech Academy of Sciences Publication Activity Database

    Švábenská, Eva; Roupcová, Pavla; Schneeweiss, Oldřich

    Ostrava: Tanger, 2015. ISBN 978-80-87294-59-8. [NANOCON 2015. International Conference /7./. Brno (CZ), 14.10.2015-16.10.2015] R&D Projects: GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : nanoparticles * wear debris * automotive brake Subject RIV: JJ - Other Materials

  5. Friction characteristics of a brake friction material under different braking conditions

    International Nuclear Information System (INIS)

    Highlights: • The tribological behavior of the brake material is well depending on interfacial temperature and friction conditions. • The friction performance is influenced by the material heterogeneity and its anisotropy. • The friction performance depended on the nature, morphology and orientation of constituents. - Abstract: As the evaluation of the tribological properties of the brake lining material is important for the braking performance identification, a pad-on-disc friction and wear tests of a commercial brake pad material against cast iron disc were conducted under low, middle and severe conditions. Three experiments via (t1), (t2) and (t3) with different sliding speeds and nominal contact pressure were conducted. Tests were performed with the pad in periodic sliding contact for 30 cycles. The scanning electronic microscopic (SEM) analysis with energy dispersive X-ray (EDX) was used to characterize the rubbed surface. The results showed that during the run-in period, the coefficient of friction increases steadily. For the friction mechanism: (i) at lower conditions, a stable friction film was generated on the surface of the brake pad, providing excellent friction stability with less wear, (ii) at middle conditions, fibers were agglomerated and were not contributed more, and (iii) at higher conditions, contact plates were identified which were accommodated the speed and the load

  6. 76 FR 44829 - Federal Motor Vehicle Safety Standards; Air Brake Systems

    Science.gov (United States)

    2011-07-27

    ... 6x4 tractor with a 190-inch wheelbase, equipped with a hybrid disc brake configuration. The vehicle... National Highway Traffic Safety Administration 49 CFR Part 571 RIN 2127-AK84 Federal Motor Vehicle Safety... published a final rule that amended the Federal motor vehicle safety standard for air brake systems...

  7. Experimental investigations for uncertainty quantification in brake squeal analysis

    Science.gov (United States)

    Renault, A.; Massa, F.; Lallemand, B.; Tison, T.

    2016-04-01

    The aim of this paper is to improve the correlation between the experimental and the numerical prediction of unstable frequencies for automotive brake systems considering uncertainty. First, an experimental quantification of uncertainty and a discussion analysing the contributions of uncertainty to a numerical squeal simulation are proposed. Frequency and transient simulations are performed considering nominal values of model parameters, determined experimentally. The obtained results are compared with those derived from experimental tests to highlight the limitation of deterministic simulations. The effects of the different kinds of uncertainty detected in working conditions of brake system, the pad boundary condition, the brake system material properties and the pad surface topography are discussed by defining different unstable mode classes. Finally, a correlation between experimental and numerical results considering uncertainty is successfully proposed for an industrial brake system. Results from the different comparisons reveal also a major influence of the pad topography and consequently the contact distribution.

  8. The influence of tyre contact patch and on the stopping distance of automotive vehicles

    OpenAIRE

    Selig, Michael; Ball, Andrew; Ash, J.; Schmidt, K.

    2012-01-01

    This contribution presents the experimental tests results about the influence of the tyre contact patch on the stopping distance of automotive vehicles. The objective of the performed tests is the evaluation of the effect of tyre inflation pressure, hence the resulting tyre contact patch on the braking system and the brake distance. The conditions of the experiment are a dry and level road surface without steering inputs. To record scientific results, a brake robot system is used. The benefit...

  9. Pulsar Braking Indices Revisited

    CERN Document Server

    Johnston, S; Johnston, Simon; Galloway, David

    1999-01-01

    Using the standard equation for the slowdown of a neutron star, we derive a formula for the braking index via integration rather than the conventional differentiation. The new formula negates the need to measure the second time derivative of the rotation frequency. We show that the method gives similar braking indices for PSR B1509-58 and the Crab pulsar to those already in the literature. We point out that our method is useful for obtaining the braking indices of moderate aged pulsars without the need for long, phase-connected timing solutions. We applied the method to 20 pulsars and discuss the implications of the results. We find that virtually all the derived braking indices are dominated by the effects of (unseen) glitches, the recovery from which corrupts the value of the frequency first derivative. However, any real, large, positive braking index has implications for magnetic field decay and offers support to recent models of pulsar evolution.

  10. WIND BRAKING OF MAGNETARS

    Energy Technology Data Exchange (ETDEWEB)

    Tong, H. [Xinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi, Xinjiang 830011 (China); Xu, R. X.; Qiao, G. J. [KIAA and School of Physics, Peking University, Beijing 100871 (China); Song, L. M., E-mail: tonghao@xao.ac.cn [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2013-05-10

    We explore the wind braking of magnetars considering recent observations challenging the traditional magnetar model. There is evidence for strong multipole magnetic fields in active magnetars, but the dipole field inferred from spin-down measurements may be strongly biased by particle wind. Recent observations challenging the traditional model of magnetars may be explained naturally by the wind braking scenario: (1) the supernova energies of magnetars are of normal value; (2) the non-detection in Fermi observations of magnetars; (3) the problem posed by low magnetic field soft gamma-ray repeaters; (4) the relation between magnetars and high magnetic field pulsars; and (5) a decreasing period derivative during magnetar outbursts. Transient magnetars with L{sub x}<- E-dot{sub rot} may still be magnetic dipole braking. This may explain why low luminosity magnetars are more likely to have radio emissions. A strong reduction of the dipole magnetic field is possible only when the particle wind is very collimated at the star surface. A small reduction of the dipole magnetic field may result from detailed considerations of magnetar wind luminosity. In the wind braking scenario, magnetars are neutron stars with a strong multipole field. For some sources, a strong dipole field may no longer be needed. A magnetism-powered pulsar wind nebula will be one of the consequences of wind braking. For a magnetism-powered pulsar wind nebula, we should see a correlation between the nebula luminosity and the magnetar luminosity. Under the wind braking scenario, a braking index smaller than three is expected. Future braking index measurement of a magnetar may tell us whether magnetars are wind braking or magnetic dipole braking.

  11. WIND BRAKING OF MAGNETARS

    International Nuclear Information System (INIS)

    We explore the wind braking of magnetars considering recent observations challenging the traditional magnetar model. There is evidence for strong multipole magnetic fields in active magnetars, but the dipole field inferred from spin-down measurements may be strongly biased by particle wind. Recent observations challenging the traditional model of magnetars may be explained naturally by the wind braking scenario: (1) the supernova energies of magnetars are of normal value; (2) the non-detection in Fermi observations of magnetars; (3) the problem posed by low magnetic field soft gamma-ray repeaters; (4) the relation between magnetars and high magnetic field pulsars; and (5) a decreasing period derivative during magnetar outbursts. Transient magnetars with Lxrot may still be magnetic dipole braking. This may explain why low luminosity magnetars are more likely to have radio emissions. A strong reduction of the dipole magnetic field is possible only when the particle wind is very collimated at the star surface. A small reduction of the dipole magnetic field may result from detailed considerations of magnetar wind luminosity. In the wind braking scenario, magnetars are neutron stars with a strong multipole field. For some sources, a strong dipole field may no longer be needed. A magnetism-powered pulsar wind nebula will be one of the consequences of wind braking. For a magnetism-powered pulsar wind nebula, we should see a correlation between the nebula luminosity and the magnetar luminosity. Under the wind braking scenario, a braking index smaller than three is expected. Future braking index measurement of a magnetar may tell us whether magnetars are wind braking or magnetic dipole braking.

  12. Wind Braking of Magnetars

    Science.gov (United States)

    Tong, H.; Xu, R. X.; Song, L. M.; Qiao, G. J.

    2013-05-01

    We explore the wind braking of magnetars considering recent observations challenging the traditional magnetar model. There is evidence for strong multipole magnetic fields in active magnetars, but the dipole field inferred from spin-down measurements may be strongly biased by particle wind. Recent observations challenging the traditional model of magnetars may be explained naturally by the wind braking scenario: (1) the supernova energies of magnetars are of normal value; (2) the non-detection in Fermi observations of magnetars; (3) the problem posed by low magnetic field soft gamma-ray repeaters; (4) the relation between magnetars and high magnetic field pulsars; and (5) a decreasing period derivative during magnetar outbursts. Transient magnetars with L_x{rot may still be magnetic dipole braking. This may explain why low luminosity magnetars are more likely to have radio emissions. A strong reduction of the dipole magnetic field is possible only when the particle wind is very collimated at the star surface. A small reduction of the dipole magnetic field may result from detailed considerations of magnetar wind luminosity. In the wind braking scenario, magnetars are neutron stars with a strong multipole field. For some sources, a strong dipole field may no longer be needed. A magnetism-powered pulsar wind nebula will be one of the consequences of wind braking. For a magnetism-powered pulsar wind nebula, we should see a correlation between the nebula luminosity and the magnetar luminosity. Under the wind braking scenario, a braking index smaller than three is expected. Future braking index measurement of a magnetar may tell us whether magnetars are wind braking or magnetic dipole braking.

  13. Recycling glass fibre-reinforced plastics in the automotive sector

    OpenAIRE

    Regenfelder, M.; Faller, J; Dully, S.; Perthes, H.; Williams, I. D.; den Boer, E.; Obersteiner, G.; Scherhaufer, S.

    2014-01-01

    The automotive sector is facing the challenge to become more resource-efficient in the manufacture of cars and their components. One approach is to increase the share of recycled materials. This paper presents the results of a case study for the automotive sector of the EU-funded Zerowin project. A safety-relevant component of the braking system was selected for manufacture using a mechanically recycled composite plastic material (polyethylene terephthalate reinforced with short glas...

  14. Can non-ideal magnetohydrodynamics solve the magnetic braking catastrophe?

    Science.gov (United States)

    Wurster, James; Price, Daniel J.; Bate, Matthew R.

    2016-03-01

    We investigate whether or not the low ionization fractions in molecular cloud cores can solve the `magnetic braking catastrophe', where magnetic fields prevent the formation of circumstellar discs around young stars. We perform three-dimensional smoothed particle non-ideal magnetohydrodynamics (MHD) simulations of the gravitational collapse of one solar mass molecular cloud cores, incorporating the effects of ambipolar diffusion, Ohmic resistivity and the Hall effect alongside a self-consistent calculation of the ionization chemistry assuming 0.1 μm grains. When including only ambipolar diffusion or Ohmic resistivity, discs do not form in the presence of strong magnetic fields, similar to the cases using ideal MHD. With the Hall effect included, disc formation depends on the direction of the magnetic field with respect to the rotation vector of the gas cloud. When the vectors are aligned, strong magnetic braking occurs and no disc is formed. When the vectors are anti-aligned, a disc with radius of 13 au can form even in strong magnetic when all three non-ideal terms are present, and a disc of 38 au can form when only the Hall effect is present; in both cases, a counter-rotating envelope forms around the first hydrostatic core. For weaker, anti-aligned fields, the Hall effect produces massive discs comparable to those produced in the absence of magnetic fields, suggesting that planet formation via gravitational instability may depend on the sign of the magnetic field in the precursor molecular cloud core.

  15. A Secure Mechanism to Supervise Automotive Sensor Network by Client on Smart Phone

    OpenAIRE

    T R Yashavanth,; Ravi S Malashetty,; V R Udupi

    2013-01-01

    This paper presents a proposal on design of a secure client on smart phone to monitor automotive sensor network. Recently, more and more vehicles, such as BMW X5, are connected from outside via smart phone [3]. From smart phone, users can use the internet resources in automotive. Users can monitor the automotives by using their smart phones. When the automotive is moving or stolen by robber, alert information will be reported to users and users can even brake their automotive via smart phone ...

  16. Development of hydraulic brake actuator for active brake control; Active brake seigyoyo yuatsu booster no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, Y.; Hattori, M. Sugisawa, M.; Nishii, M. [Aisin Seiki Co. Ltd., Aichi (Japan)

    1997-10-01

    Recently, application of active brake control systems of the vehicle are increasing. (Vehicle stability control, Panic brake assist ) We have developed a new hydraulic brake actuator for active brake control systems. New hydraulic brake actuator is composed of the three parts. (Hydraulic booster unit, Power supply unit, Control valve unit) This report describes the construction of the new hydraulic booster unit. 2 refs., 10 figs.

  17. Braking System Modeling and Brake Temperature Response to Repeated Cycle

    Directory of Open Access Journals (Sweden)

    Zaini Dalimus

    2014-12-01

    Full Text Available Braking safety is crucial while driving the passenger or commercial vehicles. Large amount of kinetic energy is absorbed by four brakes fitted in the vehicle. If the braking system fails to work, road accident could happen and may result in death. This research aims to model braking system together with vehicle in Matlab/Simulink software and measure actual brake temperature. First, brake characteristic and vehicle dynamic model were generated to estimate friction force and dissipated heat. Next, Arduino based prototype brake temperature monitoring was developed and tested on the road. From the experiment, it was found that brake temperature tends to increase steadily in long repeated deceleration and acceleration cycle.

  18. Development of brake assist system. Summary of hydraulic brake assist system; Brake assist system no kaihatsu. Ekiatsushiki brake assist system no gaiyo

    Energy Technology Data Exchange (ETDEWEB)

    Hara, M.; Ota, M.; Shimizu, S. [Toyota, Motor Corp., Aichi (Japan)

    1997-10-01

    We have already developed vacuum-booster-type Brake Assist System that supplies additional braking power when panic braking is recognized. We are convinced that the expansion of Brake Assist System will become more important issue in the future. Therefore we have developed hydraulic Brake Assist System with increasing its controllability and reducing its discomfort. This system have a brake pressure sensor to detect emergency braking operation and an antilock device to supply additional braking power. 8 refs., 11 figs.

  19. Development of mechanical brake assist; Mechanical brake assist no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, M.; Shingyoji, S.; Nakamura, I.; Tagawa, T.; Saito, Y.; Ishihara, T.; Kobayashi, S.; Yoshida, M. [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    We have recognized that there are drivers who cannot apply strong brake pedal force , in spite of the necessity of hard braking in emergencies. We have developed a `mechanical brake assist system` which assists drivers appropriately, according to the drivers` characteristics based on studying the characteristic`s of conditions of drivers applying the brake pedal force in emergency conditions. 2 refs., 7 figs., 1 tab.

  20. 49 CFR 393.52 - Brake performance.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Brake performance. 393.52 Section 393.52... NECESSARY FOR SAFE OPERATION Brakes § 393.52 Brake performance. (a) Upon application of its service brakes... braking force is measured by a performance-based brake tester which meets the requirements of...

  1. Development of combined brake system on front and rear brakes for scooter; Scooter yo zenkorin rendo brake system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Okazaki, Y.; Itabashi, T.; Shinohara, S.; Honda, Y. [Honda R and D Co. Ltd., Tokyo (Japan)

    1997-10-01

    Scooters need appropriate front and rear wheel braking power distribution and each of front and rear brakes have been operated using right and left levers. This time, a low cost brakes with cable type combined brake system for small size scooter and a brakes with hydraulic type combined brake system for middle size scooter have been developed to obtain appropriate front and rear wheel braking power distribution. Both systems use convenient left lever to operate. 3 refs., 9 figs., 1 tab.

  2. Investigation of Friction Behaviors of Brake Shoe Materials using Metallic Filler

    Directory of Open Access Journals (Sweden)

    E. Surojo

    2015-12-01

    Full Text Available Some vehicles use brake shoe made from semi-metallic materials. Semi-metallic brake shoes are made from a combination of metallic and non-metallic materials. Metallic particles are added in the formulation of brake shoe material to improve composites characteristics. In this paper, friction behaviors of brake shoe material using metallic filler were investigated. Machining chips of cast iron and copper wire of electric motor used were incorporated in composite as metallic fillers with amount 0, 2, and 4 vol. %. Friction testing was performed to measure coefficient of friction by pressing surface specimen against the surface of rotating disc. The results show that cast iron chip and Cu short wire have effect on increasing coefficient of friction of brake shoe material. They form contact plateau at contact surface. At contact surface, the Cu short wires which have parallel orientation to the sliding contact were susceptible to detach from the matrix.

  3. Wind braking of magnetars

    CERN Document Server

    Tong, H; Song, L M; Qiao, G J

    2012-01-01

    Anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs) are magnetar candidates. During their studies, the magnetic dipole braking mechanism is often assumed. This will result in a high surface dipole field for most AXPs and SGRs. It will also bring several problems challenging the magnetar interpretation. Alternatively, it is possible that AXPs and SGRs are braked down by a particle wind which also originates from magnetic field decay. In the wind braking scenario, magnetars are neutron stars with strong multipole field. A strong dipole field is no longer required. Recent challenging observations of magnetars may be explained naturally in the wind braking scenario: (1) The supernova energetics of those associated with magnetars are of normal value; (2) The non-detection in Fermi observations of magnetars; (3) The problem posed by the low-magnetic field soft gamma-ray repeater; (4) The relation between magnetars and high magnetic field pulsars ; (5) A decreasing period derivative during magnetar ou...

  4. Automotive sensors

    Science.gov (United States)

    Marek, Jiri; Illing, Matthias

    2003-01-01

    Sensors are an essential component of most electronic systems in the car. They deliver input parameters for comfort features, engine and emission control as well as for the active and passive safety systems. New technologies such as silicon micromachining play an important role for the introduction of these sensors in all vehicle classes. The importance and use of these sensor technologies in today"s automotive applications will be shown in this article. Finally an outlook on important current developments and new functions in the car will be given.

  5. Comparative analysis into the tractor-trailer braking dynamics: tractor with single axle brakes, tractor with all wheel brakes

    Science.gov (United States)

    Nastasoiu, Mircea; Ispas, Nicolae

    2014-06-01

    The paper elaborates a mathematical model in order to conduct a study into the dynamics of tractor-trailer systems during braking. The braking dynamics is analyzed by considering two versions for the braking system: 1) braking applied on the rear axle and 2) braking applied on all four wheels. In both versions the trailer is braked on all wheels. The mathematical model enables us to determine and graphically illustrate the evolution of the following parameters: braking deceleration, braking speed and the distance traveled by the tractor during braking. The mathematical model elaborated is applied on a tractor-trailer system completing transportation works.

  6. Experiments with airplane brakes

    Science.gov (United States)

    Michael, Franz

    1931-01-01

    This report begins by examining the forces on the brake shoes. For the determination of the load distribution over the shoes it was assumed that the brake linings follow Hooke's law, are neatly fitted and bedded in by wear. The assumption of Hooke's law, that is, the proportionality between compression of the lining and the absorption of force, is fulfilled to a certain extent for the loading, as becomes apparent from the load tests described further on. But there is a material discrepancy at unloading. From the load distribution we merely defined the position of the normal force resultant, while for the rest, the effect of the distribution was disregarded in the comparison of the different shoe dispositions.

  7. Tether Deployer And Brake

    Science.gov (United States)

    Carroll, Joseph A.; Alexander, Charles M.

    1993-01-01

    Design concept promises speed, control, and reliability. Scheme for deploying tether provides for fast, free, and snagless payout and fast, dependable braking. Developed for small, expendable tethers in outer space, scheme also useful in laying transoceanic cables, deploying guidance wires to torpedoes and missiles, paying out rescue lines from ship to ship via rockets, deploying antenna wires, releasing communication and power cables to sonobuoys and expendable bathythermographs, and in reeling out lines from fishing rods.

  8. A Secure Mechanism to Supervise Automotive Sensor Network by Client on Smart Phone

    Directory of Open Access Journals (Sweden)

    T R Yashavanth,

    2013-04-01

    Full Text Available This paper presents a proposal on design of a secureclient on smart phone to monitor automotive sensornetwork. Recently, more and more vehicles, such asBMW X5, are connected from outside via smartphone [3]. From smart phone, users can use theinternetresources in automotive.Users can monitorthe automotives by using their smart phones. Whenthe automotive is moving or stolen byrobber, alertinformation will be reported to users and users caneven brake their automotive via smart phone inemergency status by sending control command tothe vehicle information gateway. So client softwarein smart phone is required to monitor the sensornetwork in automotives.In order to preventmalicious attack on the client software by maliciousattackers which are usually the robbers, thereshould be a mechanism provided to the clientswhich offers security by considering few criteria’slike power of computation, level of security andconsumption of power. This proposed method usesIDEA for the encryption of all the messages since

  9. Techno-economic requirements for automotive composites

    Science.gov (United States)

    Arnold, Scot

    1993-01-01

    New technology generally serves two main goals of the automotive industry: one is to enable vehicles to comply with various governmental regulations and the other is to provide a competitive edge in the market. The latter goal can either be served through improved manufacturing and design capabilities, such as computer aided design and computer aided manufacturing, or through improved product performance, such as anti-lock braking (ABS). Although safety features are sometimes customer driven, such as the increasing use of airbags and ABS, most are determined by regulations as outlined by the Federal Motor Vehicle Safety Standards (FMVSS). Other standards, set by the Environmental Protection Agency, determine acceptable levels of emissions and fuel consumption. State governments, such as in California, are also setting precedent standards, such as requiring manufacturers to offer zero-emission vehicles as a certain fraction of their sales in the state. The drive to apply new materials in the automobile stems from the need to reduce weight and improve fuel efficiency. Topics discussed include: new lightweight materials; types of automotive materials; automotive composite applications; the role for composite materials in automotive applications; advantages and disadvantages of composite materials; material substitution economics; economic perspective; production economics; and composite materials production economics.

  10. Offline Analysis of Independent Guarded Assertions in Automotive Integration Testing

    OpenAIRE

    Rodriguez-Navas, Guillermo; Kobetski, Avenir; Sundmark, Daniel; Gustafsson, Thomas

    2015-01-01

    The size and complexity of software in automotive systems have increased steadily over the last decades. Modern vehicles typically contain numerous electrical control units (ECUs), and more and more features require real-time interaction between several dedicated ECUs (e.g., gearbox, brake and engine control units) in order to perform their tasks. Since system safety and reliability must not be adversely affected by this increase in complexity, proper quality assurance is a must. Such quality...

  11. Automotive electronics

    Energy Technology Data Exchange (ETDEWEB)

    Basshuysen, R. van [ed.; Baun, R. [comp.

    2000-10-01

    Electronic equipment is indispensable in modern motor cars for active and passive safety, exhaust and consumption monitoring or comfort. Electric and electronic systems today account for nearly 20 percent of the production cost of a normal passenger car, with an upward trend. Infotainment equipment is a growing market, which gets center stage in this issue. Further subjects discussed are current electronic and mechatronic applications as well as new developments in data transmission, development tools and constructional elements. [German] Ohne Elektronik sind moderne Automobile nicht mehr vorstellbar. Ob aktive oder passive Sicherheit, Abgas, Verbrauch oder Komfort - der Fortschritt im Autombil ist eng verknuepft mit der Einfuehrung neuer elektronischer Systeme und Komponenten. Obwohl meist nicht sehr auffaellig in einer Black-box verpackt, liegen die anteiligen Herstellungskosten fuer die Elektrik und Elektronik bei einem Mittelklassefahrzeug schon bei knapp 20 Prozent. Tendenz: Weiter steigend. Waehrend die Segnungen von ABS, ESP oder Motormanagement fuer den Kunden unsichtbar bleiben, tritt die Elektronik mit den Infotainment-Systemen ins Rampenlicht. Hochwertige Audio-Anlagen im Doppel-DIN-Format und grosse Farbbildschirme sitzen an prominenter Stelle im Armaturenbrett. Elektronische Systeme werden damit fuer den Kunden sichtbar, greifbar und erlebbar. Doch je mehr Funktionen integriert werden, desto wichtiger wird eine einfache Bedienung, die den Fahrer moeglichst wenig vom Verkehrsgeschehen ablenkt. Das ist leider keine Selbstverstaendlichkeit: Eine klare, einfache Bedienung wurde in der Vergangenheit schon bei so manchem simplen Cassetten-Radio schmerzlich vermisst. Infotainment im Automobil ist ein Wachstumsmarkt - und das Schwerpunkt-Thema der vorliegenden zweiten Ausgabe von 'Automotive Electronics'. Darueber hinaus beschaeftigt sich auch diese Ausgabe mit aktuellen Elektronik- und Mechatronik-Anwendungen und berichtet ueber neue Entwicklungen

  12. Automotive Aluminium Recycling

    Energy Technology Data Exchange (ETDEWEB)

    Gelas, B. des

    2000-07-01

    This paper aims at providing an overview on the contribution of aluminium recycling in the supply of new aluminium for automotive applications. Based on a presentation on how the global European automotive aluminium supply requirements are met, an analysis of the present and future contribution of automotive aluminium recycling is first presented. Current situation and future developments for automotive aluminium recycling practices are then commented, together with an outline on design principles for easier aluminium recycling. (orig.)

  13. 49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Air brake system and air-over-hydraulic brake... STANDARDS Vehicles With GVWR of More Than 10,000 Pounds § 570.57 Air brake system and air-over-hydraulic brake subsystem. The following requirements apply to vehicles with air brake and...

  14. Automotive vehicle sensors

    Energy Technology Data Exchange (ETDEWEB)

    Sheen, S.H.; Raptis, A.C.; Moscynski, M.J.

    1995-09-01

    This report is an introduction to the field of automotive vehicle sensors. It contains a prototype data base for companies working in automotive vehicle sensors, as well as a prototype data base for automotive vehicle sensors. A market analysis is also included.

  15. The Tribological Efficiency and the Mechanism of Action of Nano-Porous Composition Base Brake Lining Materials

    Science.gov (United States)

    Kutelia, E. R.; Gventsadze, D. I.; Eristavil, B. G.; Maisuradze, N. I.; Tsurtsumia, O. O.; Gventsadze, L. D.; Olofsson, U.; Wahlström, J.; Olander, L.

    2011-12-01

    Based on the comparative analysis of the experimental values determined for the tribological parameters for the three novel nano-porous composition base and two conventional brake lining materials while friction with the grey cast iron disc, it was shown the considerable high tribological efficiency of the novel nano-porous composition base lining materials in comparison with the conventional (from EU and USA market) brake lining materials. The explanation is given to the action mechanism of nano-porous composition base brake lining material and its tribological efficiency basing on the "triple phase" tribo-pair model.

  16. Pulsar braking: magnetodipole vs. wind

    CERN Document Server

    Tong, H

    2015-01-01

    Pulsars are good clocks in the universe. One fundamental question is that why they are good clocks? This is related to the braking mechanism of pulsars. Nowadays pulsar timing is done with unprecedented accuracy. More pulsars have braking indices measured. The period derivative of intermittent pulsars and magnetars can vary by a factor of several. However, during pulsar studies, the magnetic dipole braking in vacuum is still often assumed. It is shown that the fundamental assumption of magnetic dipole braking (vacuum condition) does not exist and it is not consistent with the observations. The physical torque must consider the presence of the pulsar magnetosphere. Among various efforts, the wind braking model can explain many observations of pulsars and magnetars in a unified way. It is also consistent with the up-to-date observations. It is time for a paradigm shift in pulsar studies: from magnetic dipole braking to wind braking. As one alternative to the magnetospheric model, the fallback disk model is also...

  17. Pulsar braking: magnetodipole vs. wind

    Science.gov (United States)

    Tong, Hao

    2016-01-01

    Pulsars are good clocks in the universe. One fundamental question is that why they are good clocks? This is related to the braking mechanism of pulsars. Nowadays pulsar timing is done with unprecedented accuracy. More pulsars have braking indices measured. The period derivative of intermittent pulsars and magnetars can vary by a factor of several. However, during pulsar studies, the magnetic dipole braking in vacuum is still often assumed. It is shown that the fundamental assumption of magnetic dipole braking (vacuum condition) does not exist and it is not consistent with the observations. The physical torque must consider the presence of the pulsar magnetosphere. Among various efforts, the wind braking model can explain many observations of pulsars and magnetars in a unified way. It is also consistent with the up-to-date observations. It is time for a paradigm shift in pulsar studies: from magnetic dipole braking to wind braking. As one alternative to the magnetospheric model, the fallback disk model is also discussed.

  18. Transient switching control strategy from regenerative braking to anti-lock braking with a semi-brake-by-wire system

    Science.gov (United States)

    Li, Liang; Li, Xujian; Wang, Xiangyu; Liu, Yahui; Song, Jian; Ran, Xu

    2016-02-01

    Regenerative braking is an important technology in improving fuel economy of an electric vehicle (EV). However, additional motor braking will change the dynamic characteristics of the vehicle, leading to braking instability, especially when the anti-lock braking system (ABS) is triggered. In this paper, a novel semi-brake-by-wire system, without the use of a pedal simulator and fail-safe device, is proposed. In order to compensate for the hysteretic characteristics of the designed brake system while ensure braking reliability and fuel economy when the ABS is triggered, a novel switching compensation control strategy using sliding mode control is brought forward. The proposed strategy converts the complex coupling braking process into independent control of hydraulic braking and regenerative braking, through which a balance between braking performance, braking reliability, braking safety and fuel economy is achieved. Simulation results show that the proposed strategy is effective and adaptable in different road conditions while the large wheel slip rate is triggered during a regenerative braking course. The research provides a new possibility of low-cost equipment and better control performance for the regenerative braking in the EV and the hybrid EV.

  19. An Eulerian Approach for Simulating Frictional Heating in Disc-Pad Systems

    OpenAIRE

    Stromberg, Niclas

    2011-01-01

    Abstract Thermal stresses as a result from frictional heating must be considered when designing disc brakes, clutches or other rotating machine components with sliding contact conditions. The rotational symmetry of the disc in these kind of applications makes it possible to model these systems using an Eulerian approach instead of a Lagrangian framework. In this paper such an approach is developed and implemented. The disc is formulated in an Eulerian frame where the convective ter...

  20. Study on the behavior of reaction disk in the vacuum brake booster; Shinkushiki bairyoku sochi ni okeru reaction disk no kyodo kaiseki jikken

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, M.; Sawada, T.; Kato, Y. [Tokyo Univ. of Agriculture and Technology, Tokyo (Japan); Ogawa, E.; Nakamura, S. [Jidosha Kiki Co. Ltd., Tokyo (Japan)

    1997-10-01

    Vacuum brake booster has been widely applied in automobiles, and it needs much time for experiments in order to design a new type model and so on. In this report concentrating on the behavior of a reaction disc, it was simulated by ARAQUS FEM program where coefficients of rubber disc are Mooney-Rivlin constants. It was shown that the numerical results represent good agreement with experiments, and in addition that values of jumping force which shows the starting point of the brake increases with the increment of the hardness of the disc, clearance and so on. 2 refs., 10 figs.

  1. Thermal Characterisation of Brake Pads

    DEFF Research Database (Denmark)

    Ramousse, Séverine; Høj, Jakob Weiland; Sørensen, O. T.

    2001-01-01

    The chemical-physical decomposition processes that occur in a brake pad heated to 1000degreesC have been studied. This temperature can be reached when a brake pad is applied. Thermogravimetry and differential thermal analysis were used in combination with evolved gas analysis, and image analysis...... using a scanning electron microscope.A brake pad is essentially a mixture of iron, carbon and binder. Combined techniques have been used, because of chemical reaction overlap, to determine how and at what temperature the binder decomposes, the coal and graphite combust and the iron oxidises.This work...

  2. Weight reduction of a standard brake drum: A design approach

    OpenAIRE

    D. Rambabu; R. Gopinath; U. Senthil rajan; G. B. Bhaskar

    2014-01-01

    A Brake drum is specialized brake that uses the concept of friction to decelerate the vehicle speed. The deceleration is achieved by the assistance of the friction generated by a set of brake shoes or pad, when operator presses against a rotating brake drum. The material generally preferred for making the brake drum is grey cast iron or vermicular cast iron. The drum brake is highly efficient for hand brake and service brake applications. During the operation of drum brake excessive heating o...

  3. The Role of Solid Lubricants for Brake Friction Materials

    Directory of Open Access Journals (Sweden)

    Werner Österle

    2016-02-01

    Full Text Available This review article comprises of three parts. Firstly, reports of brake manufacturers on the beneficial impact of solid lubricants for pad formulations are surveyed. Secondly, since tribofilms were identified to play a crucial role in friction stabilization and wear reduction, the knowledge about tribofilm structures formed during automotive braking was reviewed comprehensively. Finally, a model for simulating the sliding behavior of tribofilms is suggested and a review on modelling efforts with different model structures related to real tribofilms will be presented. Although the variety of friction composites involved in commercial brake systems is very broad, striking similarities were observed in respect to tribofilm nanostructures. Thus, a generalization of the tribofilm nanostructure is suggested and prerequisites for smooth sliding performance and minimal wear rates have been identified. A minimum of 13 vol % of soft inclusions embedded in an iron oxide based tribofilm is crucial for obtaining the desired properties. As long as the solid lubricants or their reaction products are softer than magnetite, the main constituent of the tribofilm, the model predicts smooth sliding and minimum wear.

  4. Hardware-in-the-loop of Simulation for a Hydraulic Antilock Brake System

    OpenAIRE

    Ayman A. Aly

    2013-01-01

    Hardware-In-the-Loop (HIL) of simulation policy is used as a rapid and economical tool for developing automotive systems effectively and for dangerous situations tests such as extreme road conditions or high travelling speeds. A method for building a HIL of simulation a hydraulic Antilock Braking System (ABS) based on MATLAB/Simulink is presented in this paper. The system is implemented for research purposes as well as for the application in educational process. It can help the user heighteni...

  5. Analysis of the minimum swerving distance for the development of a motorcycle autonomous braking system.

    Science.gov (United States)

    Giovannini, Federico; Savino, Giovanni; Pierini, Marco; Baldanzini, Niccolò

    2013-10-01

    In the recent years the autonomous emergency brake (AEB) was introduced in the automotive field to mitigate the injury severity in case of unavoidable collisions. A crucial element for the activation of the AEB is to establish when the obstacle is no longer avoidable by lateral evasive maneuvers (swerving). In the present paper a model to compute the minimum swerving distance needed by a powered two-wheeler (PTW) to avoid the collision against a fixed obstacle, named last-second swerving model (Lsw), is proposed. The effectiveness of the model was investigated by an experimental campaign involving 12 volunteers riding a scooter equipped with a prototype autonomous emergency braking, named motorcycle autonomous emergency braking system (MAEB). The tests showed the performance of the model in evasive trajectory computation for different riding styles and fixed obstacles. PMID:23792616

  6. Boric acid effect in phenolic composites on tribological properties in brake linings

    International Nuclear Information System (INIS)

    In the present work, using a pad-on-disc-type wear tester, the tribological properties of the pad next to the disk made of cast iron were investigated with changing the substance of the components. As well, micro-structural characterisation of braking pads was performed using scanning electron microscopy and also temperature outcome of the pads was examined at the temperatures of 50-400 oC in the pressure of 1050 and 3000 kPa. Finally, the effect of environment to the pads was studied in water, salty water, oil and braking liquid media

  7. Brake Performance Analysis of ABS for Eddy Current and Electrohydraulic Hybrid Brake System

    Directory of Open Access Journals (Sweden)

    Ren He

    2013-01-01

    Full Text Available This paper introduces an eddy current and electro-hydraulic hybrid brake system to solve problems such as wear, thermal failure, and slow response of traditional vehicle brake system. Mathematical model was built to calculate the torque of the eddy current brake system and hydraulic brake system and analyze the braking force distribution between two types of brake systems. A fuzzy controller on personal computer based on LabVIEW and Matlab was designed and a set of hardware in the loop system was constructed to validate and analyze the performance of the hybrid brake system. Through lots of experiments on dry and wet asphalt roads, the hybrid brake system achieves perfect performance on the experimental bench, the hybrid system reduces abrasion and temperature of the brake disk, response speed is enhanced obviously, fuzzy controller keeps high utilization coefficient due to the optimal slip ratio regulation, and the total brake time has a smaller decrease than traditional hydraulic brake system.

  8. RELIABILITY ANALYSIS OF CRANE BRAKE PARAMETERS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The high failure rate of crane brake results from improper choice of braking torque. The mathematical model of reliability for the crane brake parameters is introduced. Based on large amount of actual data the parameter reliabilities of 5~50 t general overhead travelling cranes are calculated,the probabilities that the braking torque is less than the static torque acting on the axle when the load moves down are obtained. Moreover,the ways to improve the reliability of brake parameters are discussed,the most reasonable values of braking safety coefficient are given.

  9. The influence of tyre contact patch and on the stopping distance of automotive vehicles

    Science.gov (United States)

    Selig, M.; Ball, A.; Ash, J.; Schmidt, K.

    2012-05-01

    This contribution presents the experimental tests results about the influence of the tyre contact patch on the stopping distance of automotive vehicles. The objective of the performed tests is the evaluation of the effect of tyre inflation pressure, hence the resulting tyre contact patch on the braking system and the brake distance. The conditions of the experiment are a dry and level road surface without steering inputs. To record scientific results, a brake robot system is used. The benefit of a robotic system is the elimination of the interfering variable driver, who is not able to apply the brake system at the same time with the same force. State-of-the-art data acquisition tools are used to log the data.

  10. The influence of tyre contact patch and on the stopping distance of automotive vehicles

    International Nuclear Information System (INIS)

    This contribution presents the experimental tests results about the influence of the tyre contact patch on the stopping distance of automotive vehicles. The objective of the performed tests is the evaluation of the effect of tyre inflation pressure, hence the resulting tyre contact patch on the braking system and the brake distance. The conditions of the experiment are a dry and level road surface without steering inputs. To record scientific results, a brake robot system is used. The benefit of a robotic system is the elimination of the interfering variable driver, who is not able to apply the brake system at the same time with the same force. State-of-the-art data acquisition tools are used to log the data.

  11. Automotive factory network renewal

    OpenAIRE

    Scicluna, Christopher

    2012-01-01

    The aim of this applied thesis was to plan, implement, and study the upgrading the network infrastructure in Valmet Automotive Oy, specifically in its Uusikaupunki factory. Valmet Automotive is a Finnish automotive service provider, focusing on premium vehicles, convertible roof systems and electric vehicles. The objective was to plan and implement a networking infrastructure that could support the load of a factory in full-scale production, while ensuring near-constant availability. T...

  12. European Automotive Congress

    CERN Document Server

    Clenci, Adrian

    2016-01-01

    The volume includes selected and reviewed papers from the European Automotive Congress held in Bucharest, Romania, in November 2015. Authors are experts from research, industry and universities coming from 14 countries worldwide. The papers are covering the latest developments in fuel economy and environment, automotive safety and comfort, automotive reliability and maintenance, new materials and technologies, traffic and road transport systems, advanced engineering methods and tools, as well as advanced powertrains and hybrid and electric drives.

  13. A global strategy based on experiments and simulations for squeal prediction on industrial railway brakes

    Science.gov (United States)

    Sinou, J.-J.; Loyer, A.; Chiello, O.; Mogenier, G.; Lorang, X.; Cocheteux, F.; Bellaj, S.

    2013-09-01

    This paper presents an overview of recent experimental and numerical investigations on industrial railway brakes. The goal of the present study is to discuss the relevance of the mechanical modeling strategy for squeal prediction. Specific experimental set-ups based on transient and controlled braking tests are designed for this purpose. Measurements are performed on it to investigate the dynamic behavior of TGV squeal noise and its squeal characterization through experiments. It will be demonstrated that it is possible to build consistent and efficient finite element models to simulate squeal events in TGV brake systems. The numerical strategy will be presented, including not only the modeling of the TGV brake system and the stability analysis, but also the transient nonlinear dynamic and computational process based on efficient reduced basis. This complete numerical strategy allows us to perform relevance squeal prediction on industrial railway brakes. This study comes within the scope of a research program AcouFren that is supported by ADEME (Agence De l'Environnement et de la Maîtrise de l'Energie) concerning the reduction of the squeal noise generated by high power railway disc brakes. experiments with an evolution of the rotational speed of the disc: these tests are called "transient braking tests" and correspond to real braking tests, experiments with a controlled steady rotational speed (i.e. dynamic fluctuations in rotational speed are not significant): these tests are called "controlled braking tests". In the present study, the Continuous Wavelet Transform (CWT) [20] is used to study the time-history responses of the TGV brake system. So, a brief basic theory of the wavelet analysis that transforms a signal into wavelets that are well localized both in frequency and time is presented in this part of the paper. Considering a function f(t), the associated Continuous Wavelet Transform (CWT) corresponds to a wavelet transform given by W(a,b

  14. Magnetic braking in ultracompact binaries

    CERN Document Server

    Farmer, Alison

    2010-01-01

    Angular momentum loss in ultracompact binaries, such as the AM Canum Venaticorum stars, is usually assumed to be due entirely to gravitational radiation. Motivated by the outflows observed in ultracompact binaries, we investigate whether magnetically coupled winds could in fact lead to substantial additional angular momentum losses. We remark that the scaling relations often invoked for the relative importance of gravitational and magnetic braking do not apply, and instead use simple non-empirical expressions for the braking rates. In order to remove significant angular momentum, the wind must be tied to field lines anchored in one of the binary's component stars; uncertainties remain as to the driving mechanism for such a wind. In the case of white dwarf accretors, we find that magnetic braking can potentially remove angular momentum on comparable or even shorter timescales than gravitational waves over a large range in orbital period. We present such a solution for the 17-minute binary AM CVn itself which a...

  15. Brakes, brake control and driver assistance systems function, regulation and components

    CERN Document Server

    2014-01-01

    Braking systems have been continuously developed and improved throughout the last years. Major milestones were the introduction of antilock braking system (ABS) and electronic stability program. This reference book provides a detailed description of braking components and how they interact in electronic braking systems. Contents Motor vehicle safety.- Basic principles of vehicle dynamics.- Car braking systems.- Car braking-system components.- Wheel brakes.- Antilock breaking systems.- Traction control system.- Electronic stability program.- Automatic brake functions.- Hydraulic modulator.- Sensors for brake control.- Sensotronic brake control.- Active steering.- Occupant protection systems.- Driver assistance systems.- Adaptive cruise control.- Parking systems.- Instrumentation.- Orientation methods.- Navigation systems.- Workshop technology. The target groups Motor-vehicle technicians in education and vocational training Master-mechanics and technicians in garage-workshops Teachers and lecturers in vocation...

  16. BRAKING OF HIGH-SPEED PASSENGER TRAINS WITH REGARD TO THE OPERATION OF AN ELECTROMAGNETIC RAIL BRAKE

    Directory of Open Access Journals (Sweden)

    N. Je. Naumenko

    2009-03-01

    Full Text Available The research of the braking process of high-speed passenger train with the use of compressed-air, electropneumatic and electromagnetic track brakes is carried out. The dependences of braking distance on motion speed for vehicles equipped by block or disk brakes as well as for a case of electromagnetic track brakes used in addition to existing braking means.

  17. 汽车用胶管的发展%Development of Automotive Hose

    Institute of Scientific and Technical Information of China (English)

    孙克俭

    2014-01-01

    介绍汽车液压制动胶管、汽车动力转向胶管和汽车制冷系统胶管等的主体材料、结构及其发展。DOT4和DOT5等新型制动液以及二氧化碳和HFO-1234yf等新型制冷剂的应用对胶管性能提出了更高的要求。随着汽车电子制动系统和电动转向系统的发展,汽车胶管在制动和转向这2个领域的应用将有所减少。%The development of materials and hose structure for automotive hydraulic brake hose, power steering hose and cooling system hose is presented in this paper. With the use of new brake lfuid DOT4 and DOT5, new refrigerant carbon dioxide and HFO-1234yf, the performance requirements on automotive hoses are raised. At the same time, as the increasing use of electronic braking system and electronic power steering system, the usage of automotive hose in the braking and steering systems would be reduced.

  18. Kentucky's Automotive Certification Program.

    Science.gov (United States)

    Kentucky State Dept. of Education, Frankfort. Office of Vocational Education.

    The state of Kentucky recognized a need to standardize automotive mechanics training throughout the state and to establish minimum guidelines for the quality of instruction in such programs. To meet these needs, the Office of Vocational Education selected the National Institute for Automotive Service Excellence (ASE) and began the certification…

  19. Automotive Industry in Malaysia

    DEFF Research Database (Denmark)

    Wad, Peter; Govindaraju, V.G.R. Chandran

    2011-01-01

    This paper explains the evolution and assesses the development of the Malaysian automotive industry within the premise of infant industry and trade protection framework as well as extended arguments of infant industry using a global value chain perspective. The Malaysian automotive industry...

  20. Automotive Technology Skill Standards

    Science.gov (United States)

    Garrett, Tom; Asay, Don; Evans, Richard; Barbie, Bill; Herdener, John; Teague, Todd; Allen, Scott; Benshoof, James

    2009-01-01

    The standards in this document are for Automotive Technology programs and are designed to clearly state what the student should know and be able to do upon completion of an advanced high-school automotive program. Minimally, the student will complete a three-year program to achieve all standards. Although these exit-level standards are designed…

  1. 49 CFR 238.231 - Brake system.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Brake system. 238.231 Section 238.231... Equipment § 238.231 Brake system. Except as otherwise provided in this section, on or after September 9... train's primary brake system shall be capable of stopping the train with a service application from...

  2. Compact, Lightweight Servo-Controllable Brakes

    Science.gov (United States)

    Lovchik, Christopher S.; Townsend, William; Guertin, Jeffrey; Matsuoka, Yoky

    2010-01-01

    Compact, lightweight servo-controllable brakes capable of high torques are being developed for incorporation into robot joints. A brake of this type is based partly on the capstan effect of tension elements. In a brake of the type under development, a controllable intermediate state of torque is reached through on/off switching at a high frequency.

  3. On the potential of uncertainty analysis for prediction of brake squeal propensity

    Science.gov (United States)

    Zhang, Zhi; Oberst, Sebastian; Lai, Joseph C. S.

    2016-09-01

    Brake squeal is a source of significant warranty-related claims for automotive manufacturers because it is annoying and is often perceived by customers as a safety concern. A brake squeal analysis is complex due to changing environmental and operating conditions, high sensitivity to manufacturing and assembly tolerances as well as the not so well understood role of nonlinearities. Although brake squeal is essentially a nonlinear problem, the standard analysis tool in industry is the linear complex eigenvalue analysis (CEA) which may under-predict or over-predict the number of unstable vibration modes. A nonlinear instability analysis is more predictive than CEA but is still computationally too expensive to be used routinely in industry for a full brake finite element model. Also, although the net work analysis of a linearised brake system has shown potential in predicting the origin of brake squeal, it has not been extensively used. In this study, the net work of an analytical viscously damped self-excited 4-dof friction oscillator with cubic contact force nonlinearity is compared with the instability prediction using the CEA and a nonlinear instability analysis. Results show that both the net work analysis and CEA under-predict the instability because of their inability to detect the sub-critical Hopf bifurcation. Then, the uncertainty analysis is applied to examine if it can improve instability prediction of a nonlinear system using linear methods and its limitations. By applying a variance-based global sensitivity analysis to parameters of the oscillator, suitable candidates for an uncertainty analysis are identified. Results of uncertainty analyses by applying polynomial chaos expansions to net work and CEA correlate well with those of the nonlinear analysis, hence demonstrating the potential of an uncertainty analysis in improving the prediction of brake squeal propensity using a linear method.

  4. Brake performance of core–shell structured carbonyl iron/silica based magnetorheological suspension

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Phuong-Bac; Do, Xuan-Phu; Jeon, Juncheol; Choi, Seung-Bok [Smart Structures and Systems Laboratory, Department of Mechanical Engineering, Inha University, Incheon 402-751 (Korea, Republic of); Liu, Ying Dan [Department of Polymer Science and Engineering, Inha University, Incheon 402-751 (Korea, Republic of); State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Choi, Hyoung Jin, E-mail: hjchoi@inha.ac.kr [Department of Polymer Science and Engineering, Inha University, Incheon 402-751 (Korea, Republic of)

    2014-10-01

    Chemically stable core–shell structured magnetic particles were synthesized by coating soft-magnetic carbonyl iron (CI) microspheres with silica through a sol–gel reaction, and applied as magnetorheological (MR) materials for a specially designed small-sized MR brake. The dynamic yield stress of the MR suspension containing the synthesized particles was also measured using a rotational rheometer under an applied magnetic field. The performance characteristics of the MR brake, including field dependent torque, hysteresis, time and torque tracking control responses were examined. The results showed that with the exception of the settling time, the other response times were faster than those of the pristine CI based MR fluid. - Highlights: • Silica coated magnetic particle was fabricated as magnetorheological (MR) material. • Small-sized MR brake of disc-type was specially designed. • MR fluid based on silica coated particles exhibited improved tracking accuracy.

  5. Automotive electronics design fundamentals

    CERN Document Server

    Zaman, Najamuz

    2015-01-01

    This book explains the topology behind automotive electronics architectures and examines how they can be profoundly augmented with embedded controllers. These controllers serve as the core building blocks of today’s vehicle electronics. Rather than simply teaching electrical basics, this unique resource focuses on the fundamental concepts of vehicle electronics architecture, and details the wide variety of Electronic Control Modules (ECMs) that enable the increasingly sophisticated "bells & whistles" of modern designs.  A must-have for automotive design engineers, technicians working in automotive electronics repair centers and students taking automotive electronics courses, this guide bridges the gap between academic instruction and industry practice with clear, concise advice on how to design and optimize automotive electronics with embedded controllers.

  6. Herniated lumbar disc

    OpenAIRE

    Jordon, Jo; Konstantinou, Kika; O'Dowd, John

    2011-01-01

    Herniated lumbar disc is a displacement of disc material (nucleus pulposus or annulus fibrosis) beyond the intervertebral disc space. The highest prevalence is among people aged 30 to 50 years, with a male to female ratio of 2:1.

  7. Herniated Lumbar Disc

    Science.gov (United States)

    Herniated Lumbar Disc What is a herniated disc? Nonsurgical treatment Medication and pain management Surgery What can I expect after ... at and just below the waist. A herniated lumbar disc can press on the nerves in the spine ...

  8. Accretion and magnetic field morphology around Class 0 stage protostellar discs

    CERN Document Server

    Seifried, D; Pudritz, R E; Klessen, R S

    2014-01-01

    We analyse the results of existing and newly performed and simulations of turbulent, collapsing molecular cloud cores focussing on the formation of Class 0 stage protostellar discs and the physical conditions in their surroundings. We show that for a wide range of initial conditions rotationally supported discs are formed in the Class 0 stage already. In particular, we show that even mild, i.e. subsonic turbulent motions, reduce the magnetic braking efficiency sufficiently in order to allow Keplerian discs to form. Based on this result we suggest that already during the Class 0 stage the fraction of Keplerian discs is significantly higher than 50%. This is consistent with recent observational trends but significantly higher than predictions based on simulations with misaligned magnetic fields and disc angular momentum vectors, demonstrating the importance of turbulent motions for the formation of Keplerian discs. We show that the accretion of mass and angular momentum in the surroundings of protostellar discs...

  9. Laser metrology — a diagnostic tool in automotive development processes

    Science.gov (United States)

    Beeck, Manfred-Andreas; Hentschel, Werner

    2000-08-01

    Laser measurement techniques are widely used in automotive development processes. Applications at Volkswagen are presented where laser metrology works as a diagnostic tool for analysing and optimising complex coupled processes inside and between automotive components and structures such as the reduction of a vehicle's interior or outer acoustic noise, including brake noise, and the combustion analysis for diesel and gasoline engines to further reduce fuel consumption and pollution. Pulsed electronic speckle pattern interferometry (ESPI) and holographic interferometry are used for analysing the knocking behaviour of modern engines and for correct positioning of knocking sensors. Holographic interferometry shows up the vibrational behaviour of brake components and their interaction during braking, and allows optimisation for noise-free brake systems. Scanning laser vibrometry analyses structure-born noise of a whole car body for the optimisation of its interior acoustical behaviour.Modern engine combustion concepts such as in direct-injection (DI) gasoline and diesel engines benefit from laser diagnostic tools which permit deeper insight into the in-cylinder processes such as flow generation, fuel injection and spray formation, atomisation and mixing, ignition and combustion, and formation and reduction of pollutants. The necessary optical access inside a cylinder is realised by so-called 'transparent engines' allowing measurements nearly during the whole engine cycle. Measurement techniques and results on double-pulse particle image velocimetry (PIV) with a frequency-doubled YAG laser for in-cylinder flow analysis are presented, as well as Mie-scattering on droplets using a copper vapour laser combined with high-speed filming, and laser-induced fluorescence (LIF) with an excimer laser for spray and fuel vapour analysis.

  10. Selection of magnetorheological brake types via optimal design considering maximum torque and constrained volume

    International Nuclear Information System (INIS)

    This research focuses on optimal design of different types of magnetorheological brakes (MRBs), from which an optimal selection of MRB types is identified. In the optimization, common types of MRB such as disc-type, drum-type, hybrid-types, and T-shaped type are considered. The optimization problem is to find the optimal value of significant geometric dimensions of the MRB that can produce a maximum braking torque. The MRB is constrained in a cylindrical volume of a specific radius and length. After a brief description of the configuration of MRB types, the braking torques of the MRBs are derived based on the Herschel–Bulkley model of the MR fluid. The optimal design of MRBs constrained in a specific cylindrical volume is then analysed. The objective of the optimization is to maximize the braking torque while the torque ratio (the ratio of maximum braking torque and the zero-field friction torque) is constrained to be greater than a certain value. A finite element analysis integrated with an optimization tool is employed to obtain optimal solutions of the MRBs. Optimal solutions of MRBs constrained in different volumes are obtained based on the proposed optimization procedure. From the results, discussions on the optimal selection of MRB types depending on constrained volumes are given. (paper)

  11. National Automotive Center - NAC

    Data.gov (United States)

    Federal Laboratory Consortium — Encouraged by the advantages of collaboration, the U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC) worked with the Secretary of the...

  12. Making aerospace technology work for the automotive industry, introduction

    Science.gov (United States)

    Olson, W. T.

    1978-01-01

    NASA derived technology already in use in the automotive industry include: (1) developments in electronics design, computer systems, and quality control methods for line testing of cars and trucks; (2) a combustion analysis computer program for automotive engine research and development; (3) an infrared scanner and television display for analyzing tire design and performance, and for studying the effects of heat on the service life of V-belts, shock mounts, brakes, and rubber bearings; (4) exhaust gas analyzers for trouble shooting and emissions certification; (5) a device for reducing noise from trucks; and (6) a low cost test vehicle for measuring highway skid resistance. Services offered by NASA to facilitate access to its technology are described.

  13. Automotive Software & Service Engineering

    OpenAIRE

    Zauner, Andreas; Hoffmann, Holger; Leimeister, Jan Marco; Krcmar, Helmut

    2014-01-01

    Automotive Software und Services (ASS) sind zentrale Innovationstreiber in der Automobilindustrie und gewinnen zunehmend an Bedeutung. In diesem Arbeitsbericht beschreiben wir die aktuellen Herausforderungen bei der Erstellung von ASS sowie Entwicklungstrends in der Dom?ne, jeweils aus Sicht der wesentlichen Stakeholder in der Industrie auf Basis von 21 Experteninterviews. Dazu geben wir einen ?berblick ?ber bestehende Automotive Software und beschreiben unser methodisches Vorgehen bei der Da...

  14. 49 CFR 230.77 - Foundation brake gear.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Foundation brake gear. 230.77 Section 230.77... Tenders Brake and Signal Equipment § 230.77 Foundation brake gear. (a) Maintenance. Foundation brake gear...) Distance above the rails. No part of the foundation brake gear of the steam locomotive or tender shall...

  15. 49 CFR 570.55 - Hydraulic brake system.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Hydraulic brake system. 570.55 Section 570.55... 10,000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles with hydraulic brake systems. (a) Brake system failure indicator. The hydraulic brake system failure...

  16. Analysis of Braking Characteristic for Tire Rotary-drum Machine%轮胎转鼓试验设备制动特性分析

    Institute of Scientific and Technical Information of China (English)

    鲍晓东; 侯勇; 张绍国

    2012-01-01

    制动系统是转鼓试验设备重要的安全部件,通过分析制动系统的材料属性,建立了制动系统的简化模型.对盘式制动器在不同制动压力下的紧急制动过程进行仿真模拟,深入分析了制动系统在不同工作负荷下制动装置摩擦表面的应力、温度场分布情况以及有效的制动时间.对比不同工况下的计算结果,得到了制动盘和刹车片的应力和温度场分布规律,并且分析了制动压力与制动时间之间的关系.结果表明制动压力越大,制动时间越短,但制动系统温升越明显,相关结论为指导设备制动系统参数的合理选定提供了理论依据.%Braking system is an important safety component for the rotating, drum test equipment, through the analysis on the material properties of the braking system, the model of braking system was es-tablishea\\Emergency braking process of the disc brake was simulated under different pressure,and then friction surface stress, temperature field distribution and effective braking time of brake system in different workload stress were further analyzedAccording to the calculation results ,stress and temperature field distribution for braking disc and pad were obtained,and relationship between braking pressure and braking time was analyzed.The results show that as the braking pressure enhanced, the braking time is shorter,however, the temperature rise for braking system is more obvious.Conclusion provides a theoretical basis for brake system rational parameter selection.

  17. Electromagnetic braking for Mars spacecraft

    Science.gov (United States)

    Holt, A. C.

    1986-01-01

    Aerobraking concepts are being studied to improve performance and cost effectiveness of propulsion systems for Mars landers and Mars interplanetary spacecraft. Access to megawatt power levels (nuclear power coupled to high-storage inductive or capacitive devices) on a manned Mars interplanetary spacecraft may make feasible electromagnetic braking and lift modulation techniques which were previously impractical. Using pulsed microwave and magnetic field technology, potential plasmadynamic braking and hydromagnetic lift modulation techniques have been identified. Entry corridor modulation to reduce loads and heating, to reduce vertical descent rates, and to expand horizontal and lateral landing ranges are possible benefits. In-depth studies are needed to identify specific design concepts for feasibility assessments. Standing wave/plasma sheath interaction techniques appear to be promising. The techniques may require some tailoring of spacecraft external structures and materials. In addition, rapid response guidance and control systems may require the use of structurally embedded sensors coupled to expert systems or to artificial intelligence systems.

  18. Falling Magnets and Electromagnetic Braking

    Science.gov (United States)

    Culbreath, Christopher; Palffy-Muhoray, Peter

    2009-03-01

    The slow fall of a rare earth magnet through a copper pipe is a striking example of electromagnetic braking; this remarkable phenomenon has been the subject of a number of scientific paper s [1, 2]. In a pipe having radius R and wall thickness D, the terminal velocity of the falling magnet is proportional to (R̂4)/D. It is interesting to ask what happens in the limit as D becomes very large. We report our experimental observations and theoretical predictions of the dependence of the terminal velocity on pipe radius R for large D. [1] Y. Levin, F.L. da Silveira, and F.B. Rizzato, ``Electromagnetic braking: A simple quantitative model''. American Journal of Physics, 74(9): p. 815-817 (2006). [2] J.A. Pelesko, M. Cesky, and S. Huertas, Lenz's law and dimensional analysis. American Journal of Physics, 3(1): p. 37-39. 2005.

  19. What brakes the Crab pulsar?

    Science.gov (United States)

    Čadež, A.; Zampieri, L.; Barbieri, C.; Calvani, M.; Naletto, G.; Barbieri, M.; Ponikvar, D.

    2016-03-01

    Context. Optical observations provide convincing evidence that the optical phase of the Crab pulsar follows the radio one closely. Since optical data do not depend on dispersion measure variations, they provide a robust and independent confirmation of the radio timing solution. Aims: The aim of this paper is to find a global mathematical description of Crab pulsar's phase as a function of time for the complete set of published Jodrell Bank radio ephemerides (JBE) in the period 1988-2014. Methods: We apply the mathematical techniques developed for analyzing optical observations to the analysis of JBE. We break the whole period into a series of episodes and express the phase of the pulsar in each episode as the sum of two analytical functions. The first function is the best-fitting local braking index law, and the second function represents small residuals from this law with an amplitude of only a few turns, which rapidly relaxes to the local braking index law. Results: From our analysis, we demonstrate that the power law index undergoes "instantaneous" changes at the time of observed jumps in rotational frequency (glitches). We find that the phase evolution of the Crab pulsar is dominated by a series of constant braking law episodes, with the braking index changing abruptly after each episode in the range of values between 2.1 and 2.6. Deviations from such a regular phase description behave as oscillations triggered by glitches and amount to fewer than 40 turns during the above period, in which the pulsar has made more than 2 × 1010 turns. Conclusions: Our analysis does not favor the explanation that glitches are connected to phenomena occurring in the interior of the pulsar. On the contrary, timing irregularities and changes in slow down rate seem to point to electromagnetic interaction of the pulsar with the surrounding environment.

  20. Friction Wear Property of Brake Materials by Copper-based Powder Metallurgy With Various Brake Speeds

    Institute of Scientific and Technical Information of China (English)

    LIU Jian-xiu; GAO Hong-xia; WEI Xiu-lan

    2004-01-01

    The experiment is conducted on MM-1000 friction test machine, which tests friction wear property of copper-based brake materials by powder metallurgy at different brake speeds. It shows that the coefficient of friction and wear volume are greatly influenced by brake speed. When the brake speed is 4000 r/min, which is a bit higher, the material still has a higher coefficient of friction with 0.47. When the brake speed is over 4000r/min, the coefficient of friction decreased rapidly. When the brake speed is 3000r/min, the material's wear is in its minimum. That is to say no matter how higher or lower the brake speed is the wear volume is bigger relatively. With the brake speed of the lower one it mainly refers to fatigue wear; while of higher one it mainly refers to abradant and oxidation wear.

  1. Frictional couplings of wheel with a rail in a brake control system of rail vehicles

    Directory of Open Access Journals (Sweden)

    A. Baier

    2011-06-01

    Full Text Available Purpose: Discussion on use of frictional coupling of wheel with a rail for detection of surface condition of track ways in coal mine undergrounds is the paper objective.Design/methodology/approach: The method for detection of surface condition of track ways is based on using of dedicated converter installed on the locomotive chassis with active part in a form of “tracking wheel” that moves on the rail surface together with the locomotive. The converter is equipped with a system for torque load and a sensor measuring its rotational speed. Change of track surface is determined by momentary changes in rotational speed of “tracking wheel” due to its slippage.Findings: The described method for detection of track ways surface condition enables to generate information signal which transferred to master braking control system of the locomotive eliminates excessive slippage during braking.Research limitations/implications: The presented results confirm rightness of accepted method for detection of track ways surface condition indicating for necessity of modification of developed test rig to get repeatable information about current track surface.Originality/value: The method for detection of track ways surface condition is the novelty approach to braking of rail locomotives used in the mining industry. It is also an alternative option to the present solutions based on known ABS (Anti-Lock Braking System system used in automotive industry.

  2. Broken discs: warp propagation in accretion discs

    Science.gov (United States)

    Nixon, Christopher J.; King, Andrew R.

    2012-04-01

    We simulate the viscous evolution of an accretion disc around a spinning black hole. In general, any such disc is misaligned, and warped by the Lense-Thirring effect. Unlike previous studies, we use effective viscosities constrained to be consistent with the internal fluid dynamics of the disc. We find that non-linear fluid effects, which reduce the effective viscosities in warped regions, can promote breaking of the disc into two distinct planes. This occurs when the Shakura & Sunyaev dimensionless viscosity parameter α is ≲0.3 and the initial angle of misalignment between the disc and hole is ≳45°. The break can be a long-lived feature, propagating outwards in the disc on the usual alignment time-scale, after which the disc is fully co-aligned or counter-aligned with the hole. Such a break in the disc may be significant in systems where we know the inclination of the outer accretion disc to the line of sight, such as some X-ray binaries: the inner disc, and so any jets, may be noticeably misaligned with respect to the orbital plane.

  3. Dynamics of Braking Vehicles: From Coulomb Friction to Anti-Lock Braking Systems

    Science.gov (United States)

    Tavares, J. M.

    2009-01-01

    The dynamics of braking of wheeled vehicles is studied using the Coulomb approximation for the friction between road and wheels. The dependence of the stopping distance on the mass of the vehicle, on the number of its wheels and on the intensity of the braking torque is established. It is shown that there are two regimes of braking, with and…

  4. Automotive Corporate Strategy in CEE

    OpenAIRE

    Kadlecová, Petra

    2009-01-01

    The diploma thesis shows the status of the automotive industry in the Czech Republic. It shows the trends in the Czech automotive industry in short theoretical presentation. There is a trend of the future competition from developing countries, other problems are growing raw material prices or government's limits in CO2 production. The companies connected to the automotive industry are reacting. The relevant information about the status and reactions of the Czech automotive industry companies,...

  5. Analysis and Design of Circular Plate MR Fluids Brake

    Institute of Scientific and Technical Information of China (English)

    Yang Yan; Lin Chang-Hua; Li Hui; Zhou Jing

    2004-01-01

    A magnetorheological (MR) fluids brake is a device to achieve brake by shear force of MR fluids. A MR rotary brake has the property that its braking torque changes quickly in response to an external magnetic field. In this study, the design method of the circular plate MR fluids brake is investigated theoretically. The equation of the torque transmitted by the MR fluids in the brake is derived to provide the theoretical foundation in the design of the brake. Based on this equation, after mathematically manipulated, the calculations of the volume, thickness and width of the MR fluids within the circular plate MR fluids brake are yield.

  6. TENDENCIES IN AUTOMOTIVE TRANSPORT DEVELOPMENT

    OpenAIRE

    U. D. Antushenay; T. R. Kisel

    2008-01-01

    The paper contains an analysis of export of transport services provided by the Republic automotive transport. Structure of expenses associated with operation of automotive transport facilities is presented in the paper. The paper cites directions pertaining to development of international automotive transportation.

  7. Identification for automotive systems

    CERN Document Server

    Hjalmarsson, Håkan; Re, Luigi

    2012-01-01

    Increasing complexity and performance and reliability expectations make modeling of automotive system both more difficult and more urgent. Automotive control has slowly evolved from an add-on to classical engine and vehicle design to a key technology to enforce consumption, pollution and safety limits. Modeling, however, is still mainly based on classical methods, even though much progress has been done in the identification community to speed it up and improve it. This book, the product of a workshop of representatives of different communities, offers an insight on how to close the gap and exploit this progress for the next generations of vehicles.

  8. Automotive NVH technology

    CERN Document Server

    Nijman, Eugenius; Priebsch, Hans-Herwig

    2016-01-01

    This book presents seven chapters examining selected noise, vibration and harshness (NVH) topics that are highly relevant for automotive vehicle development. These include applications following the major trends toward increased passenger comfort, vehicle electrification and lightweight design. The authors of the seven chapters, all of which are experts from the automotive industry and academia, present the foremost challenges and potential solutions in this demanding field. Among others, applications for sound optimization in downsized engines, noise optimization in electric powertrains, weight reduction options for exhaust systems, porous materials description, and the vibro-acoustic analysis of geared systems are discussed.

  9. REPORT on the TRUCK BRAKE LINING WORKSHOP and FLEET OPERATORS' SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Blau, P.J.

    2003-02-03

    The report summarizes what transpired during brake linings-related workshop held at the Fall 2003 meeting of the Technology and Maintenance Council (TMC) in Charlotte, NC. The title of the workshop was ''Developing a Useful Friction Material Rating System''. It was organized by a team consisting of Peter Blau (Oak Ridge National Laboratory), Jim Britell (National Highway Traffic Safety Administration), and Jim Lawrence (Motor and Equipment Manufacturers Association). The workshop was held under the auspices of TMC Task Force S6 (Chassis), chaired by Joseph Stianche (Sanderson Farms, Inc.). Six invited speakers during the morning session provided varied perspectives on testing and rating aftermarket automotive and truck brake linings. They were: James R. Clark, Chief Engineer, Foundation Brakes and Wheel Equipment, Dana Corporation, Spicer Heavy Axle and Brake Division; Charles W. Greening, Jr, President, Greening Test Labs; Tim Duncan, General Manager, Link Testing Services;Dennis J. McNichol, President, Dennis NationaLease; Jim Fajerski, Business Manager, OE Sales and Applications Engineering, Federal Mogul Corporation; and Peter J. Blau, Senior Materials Development Engineer, Oak Ridge National Laboratory. The afternoon break-out sessions addressed nine questions concerning such issues as: ''Should the federal government regulate aftermarket lining quality?''; ''How many operators use RP 628, and if so, what's good or bad about it?''; and ''Would there be any value to you of a vocation-specific rating system?'' The opinions of each discussion group, consisting of 7-9 participants, were reported and consolidated in summary findings on each question. Some questions produced a greater degree of agreement than others. In general, the industry seems eager for more information that would allow those who are responsible for maintaining truck brakes to make better, more informed choices

  10. 风电制动器的热-结构耦合分析%Analvsis of the thermal-structural coupling for the brake of wind-turbine generation

    Institute of Scientific and Technical Information of China (English)

    董惠敏; 孙守林; 王新波

    2012-01-01

    针对制动器紧急制动时制动盘的旋转运动规律,根据风电制动器的实际结构和热传导的基本理论,建立了制动盘的温度场的数值模型,提出了循环迭代的计算方法,并用ANSYS有限元软件模拟了制动盘的温度场.将温度场中的热单元转化成结构单元实现热-结构的间接耦合,采用184单元刚性梁特性来带动制动盘转动,从而来模拟制动盘的减速运动,在充分考虑温度场和应力场的耦合关系的情况下,提出了分步加载的方法来计算制动盘的应力场.模拟结果表明:制动盘摩擦区域的点的等效应力分布与其温度场的分布基本一致.%Specific to the rotating law of brake disc in emergently braking, according to actual structure of wind power brake as well as the theory of heat transfer,a numerical model of temperature field for the brake disc is established,and a calculation method of iterative is presented;with ANSYS finite element software the brake disc temperature field is simulated to convert the thermal unit in temperature field into structural unit to achieve the indirect coupling of thermal-structure.Meanwhile by adopting the 184 unit with rigid beam feature the rotating disc is driven to rotate the brake disc in order to simulate the decreasing of the braking disc.Therefore a method of step by step loading is presented to calculate the stress field of the braking disc in fully considering the coupling relationship of the temperature field and stress field.The simulation results show that the equivalent stress distribution of the point at the friction area of the brake disc is basically consistent with its temperature field distribution.

  11. Landing and Braking of Airplanes

    Science.gov (United States)

    Breguet, Louis

    1929-01-01

    In the numerical examples, we have considered an airplane landing in calm air in a fixed direction after crossing the border (with its obstacles) at a height of 30 m. Its stopping point is at a distance D from the obstacle, comprising: a distance D(sub 1) in regular gliding flight; a distance D(sub 2) in levelling off; a distance D(sub 3) in taxying on the ground. The calculations enable us to make out the following table, which gives an idea of the improvements to be expected in the use of various possible methods of braking in the air and on the ground.

  12. Constraining the braking indices of magnetars

    Science.gov (United States)

    Gao, Z. F.; Li, X.-D.; Wang, N.; Yuan, J. P.; Wang, P.; Peng, Q. H.; Du, Y. J.

    2016-02-01

    Because of the lack of long-term pulsed emission in quiescence and the strong timing noise, it is impossible to directly measure the braking index n of a magnetar. Based on the estimated ages of their potentially associated supernova remnants (SNRs), we estimate the values of the mean braking indices of eight magnetars with SNRs, and find that they cluster in the range of 1-42. Five magnetars have smaller mean braking indices of 1 wind-aided braking. The larger mean braking indices of n > 3 for the other three magnetars are attributed to the decay of external braking torque, which might be caused by magnetic field decay. We estimate the possible wind luminosities for the magnetars with 1 3, within the updated magneto-thermal evolution models. Although the constrained range of the magnetars' braking indices is tentative, as a result of the uncertainties in the SNR ages due to distance uncertainties and the unknown conditions of the expanding shells, our method provides an effective way to constrain the magnetars' braking indices if the measurements of the SNR ages are reliable, which can be improved by future observations.

  13. 49 CFR 236.712 - Brake pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Brake pipe. 236.712 Section 236.712 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.712 Brake pipe. A...

  14. 14 CFR 27.921 - Rotor brake.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor brake. 27.921 Section 27.921... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.921 Rotor brake. If there is a means to control the rotation of the rotor drive system independently of the engine, any limitations...

  15. 14 CFR 29.921 - Rotor brake.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor brake. 29.921 Section 29.921... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.921 Rotor brake. If there is a means to control the rotation of the rotor drive system independently of the engine, any limitations...

  16. Operation peculiarities of airplane brake systems

    Directory of Open Access Journals (Sweden)

    В. Г. Докучаев

    1999-09-01

    Full Text Available Analyzed is the loading of airplane brake systems. Complex methods are proposed for investi­gation of highly loaded brake systems. The results of investigation of the influence of various factors on technical condition of friction units are given

  17. Method and apparatus for electromagnetically braking a motor

    Science.gov (United States)

    Davis, Donald R. (Inventor); Radford, Nicolaus A (Inventor); Permenter, Frank Noble (Inventor); Parsons, Adam H (Inventor); Mehling, Joshua S (Inventor)

    2011-01-01

    An electromagnetic braking system and method is provided for selectively braking a motor using an electromagnetic brake having an electromagnet, a permanent magnet, a rotor assembly, and a brake pad. The brake assembly applies when the electromagnet is de-energized and releases when the electromagnet is energized. When applied the permanent magnet moves the brake pad into frictional engagement with a housing, and when released the electromagnet cancels the flux of the permanent magnet to allow a leaf spring to move the brake pad away from the housing. A controller has a DC/DC converter for converting a main bus voltage to a lower braking voltage based on certain parameters. The converter utilizes pulse-width modulation (PWM) to regulate the braking voltage. A calibrated gap is defined between the brake pad and permanent magnet when the brake assembly is released, and may be dynamically modified via the controller.

  18. New technical solutions of using rolling stock electrodynamical braking

    Directory of Open Access Journals (Sweden)

    Leonas Povilas LINGAITIS

    2009-01-01

    Full Text Available The paper considers some theoretical and practical problems associated with the use of traction motor are operating in the generator mode (in braking. Mathematical and graphical relationships of electrodynamic braking, taking into account the requirements raised to braking systems in rail transport are presented. The latter include discontinuity of braking process, braking force regulation, depending on the locomotive speed, mass, type of railway and other parameters. Schematic diagrams of the locomotive braking and ways of controlling the braking force by varying electric circuit parameters are presented. The authors suggested contact-free regulation method of braking resistor for controlling braking force in rheostatic braking, and resistor parameters regulate with pulse regulation mode by semiconductor devices, such as new electrical components for rolling stock – IGBT transistors operating in the key mode. Presenting energy savings power systems, which are using regenerative braking-returning energy and diesel engine or any form of hybrid traction vehicles systems, circuit diagrams, electrical parameters curves.

  19. Brake caliper with offset pads: Innovative brake technology for commercial vehicles offers opportunities to reduce weight and cost; Bremssattel mit tangential versetzten Bremsbelaegen: Innovative Radbremsentechnologie fuer Nutzfahrzeuge bietet neue Moeglichkeiten zur Gewichts- und Kostenreduzierung

    Energy Technology Data Exchange (ETDEWEB)

    Antony, P.; Blatt, P. [WABCO Radbremsen GmbH, Mannheim (Germany)

    2005-07-01

    Continuous optimizations and technical improvements showed no further potential for cost and weight reductions on basis of the conventional technique of a sliding caliper and two supported pads in the carrier. Additionally, global and technical needs are growing. With its 4th generation of air disc brakes and a new caliper concept, WABCO accounts to these developments. Characteristically for the New Generation (NG) is the caliper concept with pad offset in circumferential direction. This presentation describes construction and basics of the system, shows the usage of FEM and elements of Bionic methods and proofs its effectiveness with test bench results. Additional potential for the design of a new interfaces between brake and axle are identified. A significant improved disc cracking behavior offers possibilities for additional cost and weight savings. (orig.)

  20. What brakes the Crab pulsar?

    CERN Document Server

    Čadež, A; Barbieri, C; Calvani, M; Naletto, G; Barbieri, M; Ponikvar, D

    2015-01-01

    Optical observations provide convincing evidence that the optical phase of the Crab pulsar follows the radio one closely. Since optical data do not depend on dispersion measure variations, they provide a robust and independent confirmation of the radio timing solution. The aim of this paper is to find a global mathematical description of Crab pulsar's phase as a function of time for the complete set of published Jodrell Bank radio ephemerides (JBE) in the period 1988-2014. We apply the mathematical techniques developed for analyzing optical observations to the analysis of JBE. We break the whole period into a series of episodes and express the phase of the pulsar in each episode as the sum of two analytical functions. The first function is the best-fitting local braking index law, and the second function represents small residuals from this law with an amplitude of only a few turns, which rapidly relaxes to the local braking index law. From our analysis, we demonstrate that the power law index undergoes "inst...

  1. Bringing Excellence to Automotive

    Science.gov (United States)

    Večeřa, Pavel; Paulová, Iveta

    2012-12-01

    Market situation and development in recent years shows, that organization's ability to meet customer requirements is not enough. Successful organizations are able to exceed the expectations of all stakeholders. They are building their excellence systematically. Our contribution basically how the excellence in automotive is created using EFQM Excellence Model in Total Quality Management.

  2. Automotive Emission Control.

    Science.gov (United States)

    Lee, Billy D.; Ragazzi, Ronald

    This guide designed to assist teachers in improving instruction in the area of automotive emission control curriculum includes four areas. Each area consists of one or more units of instruction, with each instructional unit including some or all of the following basic components: Performance objectives, suggested activities for teacher and…

  3. Automotive Power Trains.

    Science.gov (United States)

    Marine Corps Inst., Washington, DC.

    This correspondence course, originally developed for the Marine Corps, is designed to provide mechanics with an understanding of the operation, maintenance, and troubleshooting of automotive power trains and certain auxiliary equipment. The course contains six study units covering basic power trains; clutch principles and operations; conventional…

  4. 汽车主动空气阻力制动系统仿真研究%Simulation study on initiative sir power brake system of the vehicle

    Institute of Scientific and Technical Information of China (English)

    付强; 赵立杰; 孙雪玲

    2012-01-01

    针对汽车防抱制动时地面制动力存在极限值无法更有效的缩减制动距离问题,提出了新型汽车主动空气阻力制动(APB)系统,分析其工作原理并进行控制模型基础仿真研究.阐述主动空气阻力制动系统理论可行性,依据压缩空气喷气助力原理的反作用应用于汽车制动系统,利用MATLAB/Simulink建立新型汽车制动系统动力学模型和APB仿真模型.设计了仿真试验,对比实施APB控制的车速与轮速曲线,试验结果表明APB控制达到缩减制动距离和制动时间的目的.%A new vehicle air power brake system (APB)is put forwarded in this paper to resolve that the braking distance can t be effective curtailed because of the maximum ground braking force during vehicle braking.Then its working principle and research on the basic simulation of control model is analyzed, in which the academic feasibility of initiative air power brake system is expatiatedAccording to the principle of compressed air power reaction against the brake system,a dynamics model of a new automotive brake system and simulation model of ABS+APB are established based on MATLAB/Simulink.i4/ierw/a/Y the simulated tests are designed to compare with the curve of vehicle speed and wheel velocity with APB, which result indicates that the cehicle speed and wheel velcocity controlled by APB can reduce braking distances and braking time.

  5. A Secure Mechanism to Supervise Automotive Sensor Network by Client on Smart Phone

    Directory of Open Access Journals (Sweden)

    T R Yashavanth

    2013-03-01

    Full Text Available This paper presents a proposal on design of a secure client on smart phone to monitor automotive sensor network. Recently, more and more vehicles, such as BMW X5, are connected from outside via smart phone [3]. From smart phone, users can use the internet resources in automotive. Users can monitor the automotives by using their smart phones. When the automotive is moving or stolen by robber, alert information will be reported to users and users can even brake their automotive via smart phone in emergency status by sending control command to the vehicle information gateway. So client software in smart phone is required to monitor the sensor network in automotives. In order to prevent malicious attack on the client software by malicious attackers which are usually the robbers, there should be a mechanism provided to the clients which offers security by considering few criteria’s like power of computation, level of security and consumption of power. This proposed method uses IDEA for the encryption of all the messages since IDEA has high level of security and suitable to implement in software and also demands on computational power is less. Record management set is being suggested for the storage of critical data which is a Java MIDlet based mechanism. Between client software and its gateway a communication management on transaction is also proposed. The verification of the key updating process is verified with model checking in UPPAAL [7].

  6. 78 FR 14546 - Seagull Maritime Agencies Private Ltd. v. Gren Automotive, Inc., Centrus Automotive Distributors...

    Science.gov (United States)

    2013-03-06

    ... Seagull Maritime Agencies Private Ltd. v. Gren Automotive, Inc., Centrus Automotive Distributors Inc., and... Limited (``SMA''), hereinafter ``Complainant,'' against Gren Automotive, Inc. (``Gren''), Centrus Automotive Distributors Inc. (``Centrus'') and Mr. Liu Shao hereinafter ``Respondents.'' Complainant...

  7. 78 FR 58518 - Notification of Proposed Production Activity; Benteler Automotive Corporation (Automotive...

    Science.gov (United States)

    2013-09-24

    ... Foreign-Trade Zones Board Notification of Proposed Production Activity; Benteler Automotive Corporation (Automotive Suspension and Body Components); Duncan, South Carolina Benteler Automotive Corporation (Benteler... produce automotive suspension components and subassemblies using certain foreign-status components....

  8. Diesel Technology: Brakes. Teacher Edition [and] Student Edition.

    Science.gov (United States)

    Hilley, Robert; Scarberry, Terry; Kellum, Mary

    This document contains teacher and student materials for a course on brakes in the diesel technology curriculum. The course consists of 12 units organized in three sections. The three units of the introductory section cover: (1) brakes; (2) wheel bearings and seals; and (3) antilock brake systems. The second section, Hydraulic Brakes, contains the…

  9. Feasibility of controlling speed-dependent low-frequency brake vibration amplification by modulating actuation pressure

    Science.gov (United States)

    Sen, Osman Taha; Dreyer, Jason T.; Singh, Rajendra

    2014-12-01

    In this article, a feasibility study of controlling the low frequency torque response of a disc brake system with modulated actuation pressure (in the open loop mode) is conducted. First, a quasi-linear model of the torsional system is introduced, and analytical solutions are proposed to incorporate the modulation effect. Tractable expressions for three different modulation schemes are obtained, and conditions that would lead to a reduction in the oscillatory amplitudes are identified. Second, these conditions are evaluated with a numerical model of the torsional system with clearance nonlinearity, and analytical solutions are verified in terms of the trends observed. Finally, a laboratory experiment with a solenoid valve is built to modulate actuation pressure with a constant duty cycle, and time-frequency domain data are acquired. Measurements are utilized to assess analytical observations, and all methods show that the speed-dependent brake torque amplitudes can be altered with an appropriate modulation of actuation pressure.

  10. History and evolution of warning labels for automotive friction products.

    Science.gov (United States)

    Kopelovich, Luda M; Thuett, Kerry A; Chapman, Pamela S; Paustenbach, Dennis J

    2014-04-01

    There have been claims over the years that asbestos-containing product manufacturers did not sufficiently warn end users early enough regarding the potential health hazards associated with their products (1930s-1990s). To address this issue, we compared the content of the warnings associated with asbestos-containing friction products (brakes, clutches, and gaskets) manufactured by the US automotive industries to what was expected by regulatory agencies during the time period in which an understanding of asbestos health hazards was being developed. We ended our evaluation around 1990, since asbestos-containing manufacturer supplied automotive products were functionally removed from commerce by 1985 in the United States. We assessed the warnings issued in users' manuals, technical service bulletins, product packaging materials, and labels placed on products themselves. Based on our evaluation, regulatory agencies had no guidelines regarding specific warning language for finished friction products, particularly when a product contained encapsulated asbestos fibers (i.e., modified by a bonding agent). Even today, federal regulations do not require labeling on encapsulated products when, based on professional judgment or sampling, user exposure is not expected to exceed the OSHA PEL. We concluded that, despite limited regulatory guidance, the US automotive industry provided adequate warnings with regards to its friction products. PMID:24518387

  11. Nonlinear Coupling Characteristics Analysis of Integrated System of Electromagnetic Brake and Frictional Brake of Car

    Directory of Open Access Journals (Sweden)

    Ren He

    2015-01-01

    Full Text Available Since theoretical guidance is lacking in the design and control of the integrated system of electromagnetic brake and frictional brake, this paper aims to solve this problem and explores the nonlinear coupling characteristics and dynamic characteristics of the integrated system of electromagnetic brake and frictional brake. This paper uses the power bond graph method to establish nonlinear coupling mathematical model of the integrated system of electromagnetic brake and frictional brake and conducts the contrastive analysis on the dynamic characteristics based on this mathematical model. Meanwhile, the accuracy of the nonlinear coupling mathematical model proposed above is verified on the hardware in the loop simulation platform, and nonlinear coupling characteristics of the integrated system are also analyzed through experiments.

  12. The influence of various pressures in pneumatic tyre on braking process of car with anti-lock braking system

    Directory of Open Access Journals (Sweden)

    Damian HADRYŚ

    2008-01-01

    Full Text Available In this article has been presented the influence of various pressures inpneumatic tyre of passenger car Fiat Panda 1.3 JTD with anti-lock braking system on chosen parameters of braking process: course of braking deceleration, maximum value of deceleration, braking distances.

  13. Screw-released roller brake

    Science.gov (United States)

    Vranish, John M. (Inventor)

    1999-01-01

    A screw-released roller brake including an input drive assembly, an output drive assembly, a plurality of locking sprags, a mechanical tripper nut for unlocking the sprags, and a casing therefor. The sprags consist of three dimensional (3-D) sprag members having pairs of contact surface regions which engage respective pairs of contact surface regions included in angular grooves or slots formed in the casing and the output drive assembly. The sprags operate to lock the output drive assembly to the casing to prevent rotation thereof in an idle mode of operation. In a drive mode of operation, the tripper is either self actuated or motor driven and is translated linearly up and down against a spline and at the limit of its travel rotates the sprags which unlock while coupling the input drive assembly to the output drive assembly so as to impart a turning motion thereto in either a clockwise or counterclockwise direction.

  14. An Intelligent Regenerative Braking Strategy for Electric Vehicles

    OpenAIRE

    Zhibin Song; Weimin Li; Guoqing Xu; Kun Xu

    2011-01-01

    Regenerative braking is an effective approach for electric vehicles (EVs) to extend their driving range. A fuzzy-logic-based regenerative braking strategy (RBS) integrated with series regenerative braking is developed in this paper to advance the level of energy-savings. From the viewpoint of securing car stability in braking operations, the braking force distribution between the front and rear wheels so as to accord with the ideal distribution curve are considered to prevent vehicles from ex...

  15. An Intelligent Regenerative Braking Strategy for Electric Vehicles

    OpenAIRE

    Guoqing Xu; Weimin Li; Kun Xu; Zhibin Song

    2011-01-01

    Regenerative braking is an effective approach for electric vehicles (EVs) to extend their driving range. A fuzzy-logic-based regenerative braking strategy (RBS) integrated with series regenerative braking is developed in this paper to advance the level of energy-savings. From the viewpoint of securing car stability in braking operations, the braking force distribution between the front and rear wheels so as to accord with the ideal distribution curve are considered to prevent vehicles from ex...

  16. Rotordynamics of automotive turbochargers

    CERN Document Server

    Nguyen-Schäfer, Hung

    2015-01-01

    Rotordynamics of automotive turbochargers is dealt with in this book encompassing the widely working field of small turbomachines under real operating conditions at the very high rotor speeds up to 300000 rpm. The broadly interdisciplinary field of turbocharger rotordynamics involves 1) Thermodynamics and Turbo-Matching of Turbochargers 2) Dynamics of Turbomachinery 3) Stability Analysis of Linear Rotordynamics with the Eigenvalue Theory 4) Stability Analysis of Nonlinear Rotordynamics with the Bifurcation Theory 5) Bearing Dynamics of the Oil Film using the Two-Phase Reynolds Equation 6) Computation of Nonlinear Responses of a Turbocharger Rotor 7) Aero and Vibroacoustics of Turbochargers 8) Shop and Trim Balancing at Two Planes of the Rotor 9) Tribology of the Bearing Surface Roughness 10) Design of Turbocharger Platforms using the Similarity Laws The rotor response of an automotive turbocharger at high rotor speeds is studied analytically, computationally, and experimentally. Due to the nonlinear character...

  17. Dynamics of braking vehicles: from Coulomb friction to anti-lock braking systems

    International Nuclear Information System (INIS)

    The dynamics of braking of wheeled vehicles is studied using the Coulomb approximation for the friction between road and wheels. The dependence of the stopping distance on the mass of the vehicle, on the number of its wheels and on the intensity of the braking torque is established. It is shown that there are two regimes of braking, with and without sliding. The advantage of using an anti-lock braking system (ABS) is put in evidence, and a quantitative estimate of its efficiency is proposed and discussed

  18. FISITA 2012 World Automotive Congress

    CERN Document Server

    2013-01-01

    Proceedings of the FISITA 2012 World Automotive Congress are selected from nearly 2,000 papers submitted to the 34th FISITA World Automotive Congress, which is held by Society of Automotive Engineers of China (SAE-China ) and the International Federation of Automotive Engineering Societies (FISITA). This proceedings focus on solutions for sustainable mobility in all areas of passenger car, truck and bus transportation. Volume 8: Vehicle Design and Testing (II) focuses on: •Automotive Reliability Technology •Lightweight Design Technology •Design for Recycling •Dynamic Modeling •Simulation and Experimental Validation •Virtual Design, Testing and Validation •Testing of Components, Systems and Full Vehicle Above all researchers, professional engineers and graduates in fields of automotive engineering, mechanical engineering and electronic engineering will benefit from this book.   SAE-China is a national academic organization composed of enterprises and professionals who focus on research, design a...

  19. Hydrogen as automotive fuel

    International Nuclear Information System (INIS)

    An assessment of the technical/economic feasibility of the use of hydrogen as an automotive fuel is made based on analyses of the following: the chemical- physical properties of hydrogen in relation to its use in internal combustion engines; the modifications necessary to adapt internal combustion engines to hydrogen use; hydrogen fuel injection systems - with water vapour injection, cryogenic injection, and the low or high pressure injection of hydrogen directly into the combustion chamber; the current commercialization status of hydrogen automotive fuels; energy efficiency ratings; environmental impacts; in-vehicle storage systems - involving the use of hydrides, high pressure systems and liquid hydrogen storage systems; performance in terms of pay-load ratio; autonomous operation; and operating costs. The paper concludes that, considering current costs for hydrogen fuel production, distribution and use, at present, the employment of hydrogen fuelled vehicles is feasible only in highly polluted urban environments where the innovative vehicle's air pollution abatement characteristics would justify its high operating costs as compared with those of conventional automotive alternatives

  20. Hunting Plan Morgan Brake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This plan provides guidelines for administration of hunting activity and for development, maintenance, and enforcement of regulations and guidelines on Morgan Brake...

  1. Integration of Gas Nitrocarburising and Oxidising in a Mass Production Line for Brake Pistons

    Institute of Scientific and Technical Information of China (English)

    Gero Walkowiak; Dieter M(u)ller; Uwe Zeibig

    2004-01-01

    The combination of wear- and corrosion resistance is a demand to a multitude of automotive parts. Several metallic coatings as hard/soft chromium or electroless nickel have been the conventional surface protection e.g. on parts as brake pistons and shock absorber or gas spring piston rods. The Corr-I-Dur(R) process - a special gasnitrocarburising and oxidising technology - has a huge potential not only in substituting those coatings but also in delivering surfaces with higher quality.The benefits of the replacement of soft chromium with Corr-I-Dur(R) and the implementation of the process in the customers production line with an annual capacity of 17 million brake pistons is described in this presentation. Starting with the demands on wear- and corrosion resistance the way of process development and the design of applicative equipment is shown. The result is a tailor-made surface solution with superior quality for deep drawn brake pistons. Two main disadvantagesoutgassing of the chromium layer and reduced corrosion resistance on the inner diameter - are eliminated by the replacement with Corr-I-Dur(R). The process-sure achievement of enhanced corrosion resistance, uniform layer thickness, negligible distortion as well as environmental and economical advantages make Corr-I-Dur(R) an excellence choice for this application.

  2. Method and apparatus for wind turbine braking

    Science.gov (United States)

    Barbu, Corneliu; Teichmann, Ralph; Avagliano, Aaron; Kammer, Leonardo Cesar; Pierce, Kirk Gee; Pesetsky, David Samuel; Gauchel, Peter

    2009-02-10

    A method for braking a wind turbine including at least one rotor blade coupled to a rotor. The method includes selectively controlling an angle of pitch of the at least one rotor blade with respect to a wind direction based on a design parameter of a component of the wind turbine to facilitate reducing a force induced into the wind turbine component as a result of braking.

  3. Improvement of Brake System of XJ-650 Workover Rig%XJ-650型修井机绞车制动系统改进

    Institute of Scientific and Technical Information of China (English)

    赵有清

    2015-01-01

    The working principle of hydraulic disc brake system of the hydraulic disc brake system is described in this paper.The problem of the existence of the pneumatic control belt brake for the XJ-650 type of the well is put forward.The hydraulic disc brake system of the workover rig is a-dapted for technological reformation,which is suitable for workover operation in deep and com-plex well conditions,and the construction of the labor intensity is decreased,security is obviously enhanced.%简述了修井机液压盘式刹车系统的工作原理。指出现有 XJ-650型修井机的气控带式刹车存在的问题。采用液压盘式刹车系统对该修井机进行技术改造,适应深井、复杂工况井等修井作业要求,并且使施工的劳动强度下降,安全性明显增强。

  4. Constraining the Braking Indices of Magnetars

    CERN Document Server

    Gao, Z F; Wang, N; Yuan, J P; Peng, Q H; Du, Y J

    2015-01-01

    Due to the lack of long term pulsed emission in quiescence and the strong timing noise, it is impossible to directly measure the braking index $n$ of a magnetar. Based on the estimated ages of their potentially associated supernova remnants (SNRs), we estimate the values of $n$ of nine magnetars with SNRs, and find that they cluster in a range of $1\\sim$41. Six magnetars have smaller braking indices of $13$ for other three magnetars are attributed to the decay of external braking torque, which might be caused by magnetic field decay. We estimate the possible wind luminosities for the magnetars with $13$ within the updated magneto-thermal evolution models. We point out that there could be some connections between the magnetar's anti-glitch event and its braking index, and the magnitude of $n$ should be taken into account when explaining the event. Although the constrained range of the magnetars' braking indices is tentative, our method provides an effective way to constrain the magnetars' braking indices if th...

  5. Automated visual inspection of brake shoe wear

    Science.gov (United States)

    Lu, Shengfang; Liu, Zhen; Nan, Guo; Zhang, Guangjun

    2015-10-01

    With the rapid development of high-speed railway, the automated fault inspection is necessary to ensure train's operation safety. Visual technology is paid more attention in trouble detection and maintenance. For a linear CCD camera, Image alignment is the first step in fault detection. To increase the speed of image processing, an improved scale invariant feature transform (SIFT) method is presented. The image is divided into multiple levels of different resolution. Then, we do not stop to extract the feature from the lowest resolution to the highest level until we get sufficient SIFT key points. At that level, the image is registered and aligned quickly. In the stage of inspection, we devote our efforts to finding the trouble of brake shoe, which is one of the key components in brake system on electrical multiple units train (EMU). Its pre-warning on wear limitation is very important in fault detection. In this paper, we propose an automatic inspection approach to detect the fault of brake shoe. Firstly, we use multi-resolution pyramid template matching technology to fast locate the brake shoe. Then, we employ Hough transform to detect the circles of bolts in brake region. Due to the rigid characteristic of structure, we can identify whether the brake shoe has a fault. The experiments demonstrate that the way we propose has a good performance, and can meet the need of practical applications.

  6. SITUATION IN RUSSIAN AUTOMOTIVE INDUSTRY AND AUTOMOTIVE MARKET IN CRISIS

    OpenAIRE

    Starkova, Nadezhda; Tolstova, Alisa; Ubogova, Ekaterina

    2015-01-01

    Todays situation of Russian automotive industry and automotive market has been analyzed. Main factors influencing for their position have been revealed, short-term forecast of development has been presented. Directions for stabilization of situation in production and sales of cars in Russia have been formulated.

  7. Geometric optimal design of a magneto-rheological brake considering different shapes for the brake envelope

    International Nuclear Information System (INIS)

    When designing a magneto-rheological brake (MRB), it is well known that the shape of the brake envelope significantly affects the performance characteristics of the brake. In this study, different shapes for the MR brake envelope, such as rectangular, polygonal or spline shape, are considered and the most suitable shape identified. MRBs with different envelope shapes are introduced followed by the derivation of the braking torque based on Bingham-plastic behavior of the magneto-rheological fluid (MRF). Optimization of the design of the MRB with different envelope shapes is then done. The optimization problem is to find the optimal value for the significant geometric dimensions of the MRB that can produce a certain required braking torque while the brake mass is minimized. A finite element analysis integrated with an optimization tool is employed to obtain optimal solutions for the MRBs. From the results, the most suitable shape for the brake envelope is identified and discussed with the reduction of mass. In addition, the results of the analysis are compared with the experimental results to verify the proposed optimal design characteristics. (paper)

  8. Braking Index of Isolated Pulsars

    CERN Document Server

    Hamil, Oliver Q; Urbanec, Martin; Urbancova, Gabriela

    2016-01-01

    Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\\Omega$, and their time derivatives that show unambiguously that the pulsars are slowing down. The commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR) from a rotating magnetized body. The calculated energy loss by a rotating pulsar with a constant moment of inertia is assumed proportional to a model dependent power of $\\Omega$. This relation leads to the power law $\\dot{\\Omega}$ = -K $\\Omega^{\\rm n}$ where $n$ is called the braking index. The MDR model predicts $n$ exactly equal to 3. Selected observations of isolated pulsars provide rather precise values of $n$, individually accurate to a few percent or better, in the range 1$ <$ n $ < $ 2.8, which is consistently less than the predictions of the MDR model. In spite of an extensive investigation of various modifications of the MDR model, no satisfactory explanation of observation has been found yet. The aim of this work is t...

  9. Embedded Automotive System Development Process

    OpenAIRE

    Langenwalter, Joachim

    2005-01-01

    Model based design enables the automatic generation of final-build software from models for high-volume automotive embedded systems. This paper presents a framework of processes, methods and tools for the design of automotive embedded systems. A steer-by-wire system serves as an example.

  10. Reliability in automotive ethernet networks

    DEFF Research Database (Denmark)

    Soares, Fabio L.; Campelo, Divanilson R.; Yan, Ying;

    2015-01-01

    This paper provides an overview of in-vehicle communication networks and addresses the challenges of providing reliability in automotive Ethernet in particular.......This paper provides an overview of in-vehicle communication networks and addresses the challenges of providing reliability in automotive Ethernet in particular....

  11. Automotive systems engineering

    CERN Document Server

    Winner, Hermann

    2013-01-01

    This book reflects the shift in design paradigm in automobile industry. It presents future innovations, often referred as  “automotive systems engineering”.  These cause fundamental innovations in the field of driver assistance systems and electro-mobility as well as fundamental changes in the architecture of the vehicles. New driving functionalities can only be realized if the software programs of multiple electronic control units work together correctly. This volume presents the new and innovative methods which are mandatory to master the complexity of the vehicle of the future.

  12. The automotive transmission book

    CERN Document Server

    Fischer, Robert; Jürgens, Gunter; Najork, Rolf; Pollak, Burkhard

    2015-01-01

    This book presents essential information on systems and interactions in automotive transmission technology and outlines the methodologies used to analyze and develop transmission concepts and designs. Functions of and interactions between components and subassemblies of transmissions are introduced, providing a basis for designing transmission systems and for determining their potentials and properties in vehicle-specific applications: passenger cars, trucks, buses, tractors, and motorcycles. With these fundamentals the presentation provides universal resources for both state-of-the-art and future transmission technologies, including systems for electric and hybrid electric vehicles.

  13. Automotive battery technology

    CERN Document Server

    Watzenig, Daniel

    2014-01-01

    The use of electrochemical energy storage systems in automotive applications also involves new requirements for modeling these systems, especially in terms of model depth and model quality. Currently, mainly simple application-oriented models are used to describe the physical behavior of batteries. This book provides a step beyond of state-of-the-art modeling showing various different approaches covering following aspects: system safety, misuse behavior (crash, thermal runaway), battery state estimation and electrochemical modeling with the needed analysis (pre/post mortem). All this different approaches are developed to support the overall integration process from a multidisciplinary point-of-view and depict their further enhancements to this process.

  14. Weight reduction of a standard brake drum: A design approach

    Directory of Open Access Journals (Sweden)

    D. Rambabu

    2014-03-01

    Full Text Available A Brake drum is specialized brake that uses the concept of friction to decelerate the vehicle speed. The deceleration is achieved by the assistance of the friction generated by a set of brake shoes or pad, when operator presses against a rotating brake drum. The material generally preferred for making the brake drum is grey cast iron or vermicular cast iron. The drum brake is highly efficient for hand brake and service brake applications. During the operation of drum brake excessive heating of brake drum may occur. This excessive heating occurs due to repeated or frequent contact of the brake shoes against the drum. This causes the drum to crack, oversize, extreme wear, out of round drums and also leads to vibration which while braking will leads to reduced brake drum life and braking efficiency. The Un-laden weight of the vehicle will result in increased fuel consumption, reduced payload and ride handling characteristics. The objective of the paper is to improve the thermal characteristics by incorporating fins in the brake drum and to reduce the un-laden weight of the vehicle by changing the rib thickness, wall thickness and base flange thickness. The design is done by using 3D CAD Modelling software and Hexahedral finite element model prepared by using CAE pre-processing software and Stiffness analysis. Design iterations are carried out by using Linear/Non-linear Finite Element Solvers, Stress Displacement and Temperature is post-processed for design validation. Optimized design solution obtained based on the comparison study between the iteration with rib thickness 75 mm, star shaped removal and wall thickness 17 mm has been chosen. 1.8Kg of weight is being reduced from the brake drum including fins.   Keywords: Drum Brake, 3D CAD Modelling, Para Metric Matrix, Structural Analysis, Fins.

  15. Double rupture disc experience

    International Nuclear Information System (INIS)

    Result of these observations, comparisons and evaluations can be summarized in the following list of concerns regarding the use of double rupture discs coupled to the liquid space of a steam generator that is subjected to a large leak sodium water reaction event. Single rupture disc show delayed collapse characteristics in LLTR Series I and double disc assemblies are presumed to be more complex with additional delay before opening to give pressure relief. Delayed failure increases pressures in the IHTS and must be adequately covered by design requirements. With CRBR design, the first disc may fail only partially reducing the loading on the second disc with the result that relief performance may not meet requirements

  16. 77 FR 51649 - Federal Motor Vehicle Safety Standards; Motorcycle Brake Systems

    Science.gov (United States)

    2012-08-24

    .... Wet Brake Test E. Heat Fade Test F. Parking Brake System Test G. Antilock Brake System (ABS.... Other ABS-Related Comments H. Partial Failure Test--Split Service Brake System I. Power-Assisted Braking..., Motorcycle Brake Systems, Notice of Proposed Rulemaking, 73 FR 54020 (Sept. 17, 2008) (hereinafter ``FMVSS...

  17. Discs, outflows, and feedback in collapsing magnetized cores

    CERN Document Server

    Duffin, Dennis

    2010-01-01

    The pre-stellar cores in which low mass stars form are generally well magnetized. Our simulations show that early protostellar discs are massive and experience strong magnetic torques in the form of magnetic braking and protostellar outflows. Simulations of protostellar disk formation suggest that these torques are strong enough to suppress a rotationally supported structure from forming for near critical values of mass-to-flux. We demonstrate through the use of a 3D adaptive mesh refinement code -- including cooling, sink particles and magnetic fields -- that one produces transient 1000 AU discs while simultaneously generating large outflows which leave the core region, carrying away mass and angular momentum. Early inflow/outflow rates suggest that only a small fraction of the mass is lost in the initial magnetic tower/jet event.

  18. ACTIVE FRONT STEERING DURING BRAKING PROCESS

    Institute of Scientific and Technical Information of China (English)

    CHEN Deling; CHEN Li; YIN Chengliang; ZHANG Yong

    2008-01-01

    An active front steering (AFS) intervention control during braking for vehicle stability is presented. Based on the investigation of AFS mechanism, a simplified model of steering system is established and integrated with vehicle model. Then the AFS control on vehicle handling dynamics during braking is designed. Due to the difficulties associated with the sideslip angle measurement of vehicle, a state observer is designed to provide real time estimation. Thereafter, the controller with the feedback of both sideslip and yaw angle is implemented. To evaluate the system control, the proposed AFS controlled vehicle has been tested in the Hardware-in-the-loop-simulation (HILS) system and compared with that of conventional vehicle. Results show that AFS can improve vehicle lateral stability effectively without reducing the braking performance.

  19. Protostellar disc formation enabled by removal of small dust grains

    Science.gov (United States)

    Zhao, Bo; Caselli, Paola; Li, Zhi-Yun; Krasnopolsky, Ruben; Shang, Hsien; Nakamura, Fumitaka

    2016-08-01

    It has been shown that a realistic level of magnetization of dense molecular cloud cores can suppress the formation of a rotationally supported disc (RSD) through catastrophic magnetic braking in the axisymmetric ideal MHD limit. In this study, we present conditions for the formation of RSDs through non-ideal MHD effects computed self-consistently from an equilibrium chemical network. We find that removing from the standard MRN distribution the large population of very small grains (VSGs) of ˜ 10 Å to few 100 Å that dominate the coupling of the bulk neutral matter to the magnetic field increases the ambipolar diffusivity by ˜ 1-2 orders of magnitude at densities below 1010/cm-3. The enhanced ambipolar diffusion (AD) in the envelope reduces the amount of magnetic flux dragged by the collapse into the circumstellar disc-forming region. Therefore, magnetic braking is weakened and more angular momentum can be retained. With continuous high angular momentum inflow, RSDs of tens of au are able to form, survive, and even grow in size, depending on other parameters including cosmic ray ionization rate, magnetic field strength, and rotation speed. Some discs become self-gravitating and evolve into rings in our 2D (axisymmetric) simulations, which have the potential to fragment into (close) multiple systems in 3D. We conclude that disc formation in magnetized cores is highly sensitive to chemistry, especially to grain sizes. A moderate grain coagulation/growth to remove the large population of VSGs, either in the prestellar phase or during free-fall collapse, can greatly promote AD and help formation of tens of au RSDs.

  20. Hillside, Morgans Brake, and Mathews Brake National Wildlife Refuges Deer Harvest Records are from 2008 and 2014

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These harvest data are from Hillside, Morgans Brake, and Mathews Brake NWRs during the 2008 and 2014 deer seasons. They measure weight, antler size, prevalence of...

  1. Biweekly Waterfowl Counts from Mathews Brake, Morgan Brake, and Hillside National Wildlife Refuges in 2001 and 2002

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Biweekly Waterfowl Counts from Mathews Brake, Morgan Brake, and Hillside National Wildlife Refuges conducted from October 2001 to February 2002

  2. Central Mississippi Refuges: Yazoo, Panther Swamp, Hillside, Morgan Brake & Bathews Brake: Annual narrative report: Calendar year 2001

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Yazoo, Hillside, Panther Swamp, Morgan Brake, and Mathews Brake NWRs covers refuge activities during 2001. The report begins with a...

  3. 30 CFR 75.1404 - Automatic brakes; speed reduction gear.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Automatic brakes; speed reduction gear. 75.1404... Automatic brakes; speed reduction gear. Each locomotive and haulage car used in an underground coal mine... brakes, locomotives and haulage cars shall be subject to speed reduction gear, or other similar...

  4. 49 CFR 238.319 - Running brake test.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Running brake test. 238.319 Section 238.319... Requirements for Tier I Passenger Equipment § 238.319 Running brake test. (a) As soon as conditions safely permit, a running brake test shall be performed on each passenger train after the train has received,...

  5. The braking indices in pulsar emission models

    CERN Document Server

    Wu, F; Gil, J; Gil, Janusz

    2003-01-01

    Using the method proposed in a previous paper, we calculate pulsar braking indices in the models with torque contributions from both inner and outer accelerating regions, assuming that the interaction between them is negligible. We suggest that it is likely that the inverse Compton scattering induced polar vacuum gap and the outer gap coexist in the pulsar magnetosphere. We include the new near threshold vacuum gap models with curvature-radiation and inverse Compton scattering induced cascades, respectively; and find that these models can well reproduce the measured values of the braking indices.

  6. Optic disc oedema

    DEFF Research Database (Denmark)

    Nielsen, Marianne Kromann; Hamann, Steffen

    2014-01-01

    Optic disc oedema describes the nonspecific, localized swelling of the optic nerve head regardless of aetiology. Therefore, differentiating among the various aetiologies depends on a thorough history and knowledge of the clinical characteristics of the underlying conditions. Papilloedema strictly...... refers to optic disc oedema as a consequence of elevated intracranial pressure. It is usually a bilateral condition and visual function is preserved until late. Optic disc oedema caused by an anterior optic neuropathy is usually unilateral and accompanied by the loss of visual function....

  7. Tank-automotive robotics

    Science.gov (United States)

    Lane, Gerald R.

    1999-07-01

    To provide an overview of Tank-Automotive Robotics. The briefing will contain program overviews & inter-relationships and technology challenges of TARDEC managed unmanned and robotic ground vehicle programs. Specific emphasis will focus on technology developments/approaches to achieve semi- autonomous operation and inherent chassis mobility features. Programs to be discussed include: DemoIII Experimental Unmanned Vehicle (XUV), Tactical Mobile Robotics (TMR), Intelligent Mobility, Commanders Driver Testbed, Collision Avoidance, International Ground Robotics Competition (ICGRC). Specifically, the paper will discuss unique exterior/outdoor challenges facing the IGRC competing teams and the synergy created between the IGRC and ongoing DoD semi-autonomous Unmanned Ground Vehicle and DoT Intelligent Transportation System programs. Sensor and chassis approaches to meet the IGRC challenges and obstacles will be shown and discussed. Shortfalls in performance to meet the IGRC challenges will be identified.

  8. 基于HHT去噪和互相关原理的ABS制动液压力波波速的研究%Research of Pressure Wave Velocity of Brake Fluid of ABS Based on HHT and Principle of Cross-correlation

    Institute of Scientific and Technical Information of China (English)

    戚雪珍; 李孝禄; 王文越

    2016-01-01

    汽车防抱死系统( ABS)依靠制动液压力波传递制动压力,对汽车制动效能影响很大。文中利用压力传感器采集ABS制动液压力,对采集的数据进行希尔伯特-黄变换( HHT)去噪,再利用互相关原理对不同刹车盘转速和制动管路长度下的制动液压力波波速进行计算。研究表明,制动液压力波波速可达1181.8 m/s。%Pressure wave velocity of brake fluid of Anti-lock braking system( ABS) have an obvious effect on brake ability of automobile, which transfers braking pressure for braking disc. The brake fluid pressure was acquired by the pressure transmitters in an ABS, and with Hilbert-huang transform ( HHT) de-noised. The pressure wave velocities of brake fluid were calculated by the cross-correlation principle under different rotating speeds and braking pipe lengths. The results show that the pressure wave velocity of brake fluid is up to 1 181.8m/s.

  9. Hillside, Morgan Brake, and Mathews Brake National Wildlife Refuges Reforestation Plan for 1992-1996

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This plan addresses the history of reforestation at Hillside National Wildlife Refuge and its two satellite refuges, Morgan Brake National Wildlife Refuge and...

  10. An Australian study to evaluate worker exposure to chrysotile in the automotive service industry.

    Science.gov (United States)

    Yeung, P; Patience, K; Apthorpe, L; Willcocks, D

    1999-07-01

    A study was conducted in Sydney, Australia, in 1996 to investigate the current exposure levels, control technologies, and work practices in five service garages (four car and one bus), three brake bonding workshops, and one gasket processing workshop. This study formed part of the assessment of chrysotile as a priority existing chemical under the Australian National Industrial Chemicals Notification and Assessment Scheme. A total of 68 (11 personal and 57 area) air samples were collected, in accordance with the Australian standard membrane filter method. Fiber concentrations were determined by the traditional phase contrast microscopy (PCM) method and 16 selected samples were analyzed by the more powerful transmission electron microscopy (TEM). Chrysotile exposure of car mechanics measured by PCM was typically below the reportable detection limit of 0.05 f/mL, irrespective of whether disc brake, drum brake, or clutch was being serviced. These low levels can be attributed to the wet cleaning or aerosol spray methods used in recent years to replace the traditional compressed air jet cleaning. In the three brake shoe relining workshops, task-specific exposure reached up to 0.16 f/mL in the processes of cutting and radius grinding. TEM results were generally higher, due to its higher resolution power. The median diameter on samples taken from the service garages (passenger cars), as determined by TEM, was 0.5-1.0 micron; and was between 0.2-0.5 micron for the brake bonding and gasket processing workshops, while that for the bus service depot was 0.1-0.2 micron. Most of the respirable fibers (84%, mainly forsterite) from the bus service depot were below 0.2 micron in diameter which is the resolution limit of PCM. In the brake bonding and gasket cutting workshops, 34 percent and 44 percent of the chrysotile fibers were below 0.2 micron in diameter. PMID:10461401

  11. LUMBAR DISC HERNIATION

    OpenAIRE

    Vialle, Luis Roberto; Vialle, Emiliano Neves; Suárez Henao, Juan Esteban; Giraldo, Gustavo

    2015-01-01

    Lumbar disc herniation is the most common diagnosis among the degenerative abnormalities of the lumbar spine (affecting 2 to 3% of the population), and is the principal cause of spinal surgery among the adult population. The typical clinical picture includes initial lumbalgia, followed by progressive sciatica. The natural history of disc herniation is one of rapid resolution of the symptoms (four to six weeks). The initial treatment should be conservative, managed through medication and physi...

  12. The European automotive LPG market

    International Nuclear Information System (INIS)

    The European automotive LPG market could reach at least 4 % of the European fuel market in 2005 versus 1 % in 1990. This would represent a rise of about 35 % in automotive LPG sales (from 2,4 million tonnes in 1997 to 7 million tonnes estimated for 2005). This was underlined by Alain Deleuse, Primagaz group's Marketing Director, in the paper he delivered at the AEGPL Budapest Convention. We publish large excepts of this paper. (author)

  13. Multicore scheduling in automotive ECUs

    OpenAIRE

    Monot, Aurélien; Navet, Nicolas; Bavoux, Bernard; Simonot-Lion, Françoise

    2010-01-01

    As the demand for computing power is quickly increasing in the automotive domain, car manufacturers and tier-one suppliers are gradually introducing multicore ECUs in their electronic architectures. Additionally, these multicore ECUs offer new features such as higher levels of parallelism which eases the espect of the safety requirements introduced by the ISO 26262 and can be taken advantage of in various other automotive use-cases. These new features involve also more complexity in the desig...

  14. Radicular interdural lumbar disc herniation

    OpenAIRE

    Akhaddar, Ali; Boulahroud, Omar; Elasri, Abad; Elmostarchid, Brahim; Boucetta, Mohammed

    2009-01-01

    Intraradicular lumbar disc herniation is a rare complication of disc disease that is generally diagnosed only during surgery. The mechanism for herniated disc penetration into the intradural space is not known with certainty, but adhesion between the radicular dura and the posterior longitudinal ligament was suggested as the most important condition. The authors report the first case of an intraradicular lumbar disc herniation without subdural penetration; the disc hernia was lodged between t...

  15. Study on reduction method of brake squeal; Brake naki teigen shuho ni kansuru kento

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, T.; Okada, Y. [Aisin Seiki Co. Ltd., Aichi (Japan)

    1997-10-01

    The reduction of brake squeal is an important technological subject in terms of making vehicles quieter. In our research, we carried out a modal analysis from the caliper to the installation bracket during generating brake squeal to identify the places that influence the squeal. Based on this, we studied proposals to reduce the squeal, and have reduced the squeal noise at about 5 kHz as reported in this paper. 1 ref., 12 figs.

  16. Radially truncated galactic discs

    CERN Document Server

    De Grijs, R; Wesson, K H; Grijs, Richard de; Kregel, Michiel; Wesson, Karen H.

    2000-01-01

    We present the first results of a systematic analysis of radially truncatedexponential discs for four galaxies of a sample of disc-dominated edge-onspiral galaxies. Edge-on galaxies are very useful for the study of truncatedgalactic discs, since we can follow their light distributions out to largerradii than in less highly inclined galaxies. The origin of these truncationsand their asymmetry and sharpness are helpful to better constrain theories ofgalaxy formation. In general, the discs of our sample galaxies are truncated at similar radiion either side of their centres. With the exception of the disc of ESO 416-G25,it appears that our sample galaxies are closely symmetric, in terms of both thesharpness of their disc truncations and the truncation length. However, thetruncations occur over a larger region and not as abruptly as found by van derKruit & Searle (KS1-4). We show that the truncated luminosity distributions of our sample galaxies,if also present in the mass distributions, comfortably meet the r...

  17. Wear determination in braking systems by radioisotopes

    International Nuclear Information System (INIS)

    Friction and wear behaviour of friction couples has been tested applying loads and sliding speeds. The determination was carried out by direct measurements of the lining material and by surface activation of the opposite material with protons. The application limits of several braking materials could be determined and compared

  18. Massive star models with magnetic braking

    CERN Document Server

    Meynet, Georges; Maeder, Andre

    2010-01-01

    Magnetic fields at the surface of a few early-type stars have been directly detected. These fields have magnitudes between a few hundred G up to a few kG. In one case, evidence of magnetic braking has been found. We investigate the effects of magnetic braking on the evolution of rotating ($\\upsilon_{\\rm ini}$=200 km s$^{-1}$) 10 M$_\\odot$ stellar models at solar metallicity during the main-sequence (MS) phase. The magnetic braking process is included in our stellar models according to the formalism deduced from 2D MHD simulations of magnetic wind confinement by ud-Doula and co-workers. Various assumptions are made regarding both the magnitude of the magnetic field and of the efficiency of the angular momentum transport mechanisms in the stellar interior. When magnetic braking occurs in models with differential rotation, a strong and rapid mixing is obtained at the surface accompanied by a rapid decrease in the surface velocity. Such a process might account for some MS stars showing strong mixing and low surfa...

  19. Asbestos free friction composition for brake linings

    Indian Academy of Sciences (India)

    Arnab Ganguly; Raji George

    2008-02-01

    An asbestos free friction material composite for brake linings is synthesized containing fibrous reinforcing constituents, friction imparting and controlling additives, elastomeric additives, fire retarding components and a thermosetting resin. The composite shows exemplary friction characteristics and has great resistance to wear and shows good temperature stability.

  20. Innovation of Electromagnetic Brake for Rail Vehicles

    Czech Academy of Sciences Publication Activity Database

    Ulrych, B.; Doležel, Ivo

    Opole : Technical University of Opole, 2005, s. 650-653. ISBN 83-88492-74-8. [International Symposium on Electrical Machines SME 2005 /41./. Opole-Jarnoltówek (PL), 14.06.2005-17.06.2005] Institutional research plan: CEZ:AV0Z20570509 Keywords : electromagnetic brake * electromagnetic field * numerical analysis Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  1. 盘式制动器

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A parametric modelling approach for the preliminary design of automotive disc brakes;A predictive tool to evaluate disc brake squeal propensity-Part 3: parametric design studies;A predictive tool to evaluate disc brake squeal propensity-Part 2: system linearisation and modal analysis;A predictive tool to evaluate disc brake squeal propensity-Part 1: the model philosophy and the contact problem;A study of disc brake high frequency squeals and dis cin-plane/out-of-plane modes……

  2. Ceramics for use in brakes and clutches; Keramik fuer den Einsatz in Bremsen und Kupplungen

    Energy Technology Data Exchange (ETDEWEB)

    Albers, A.; Arslan, A.; Herbst, D. [Karlsruhe Univ. (T.H.) (Germany). Inst. fuer Maschinenkonstruktionslehre und Kraftfahrzeugbau

    2001-05-01

    A further increase in the power density of clutches and brakes is hardly possible using conventional friction materials. Although friction linings on the basis of sintered metals allow higher power densities than organic linings, they have serious disadvantages with regard to comfort, which means that they cannot be used in vehicles. The use of innovative ceramic materials here is promising, as is shown by the following article from the Institute of Machine Design and Automotive Engineering of the University of Karlsruhe. (orig.) [German] Eine weitere Steigerung der Leistungsdichte von Kupplungen und Bremsen ist mit herkoemmlichen Reibewerkstoffen fast nicht mehr moeglich. Reibbelaege auf der Basis von Sintermetallen erlauben eine hoehere Leistung als organische Reibbelaege, jedoch haben sie gravierende Nachteile in Bezug auf Komforteigenschaften, so dass sie im Pkw nicht eingesetzt werden koennen. Erfolg verspricht die Anwendung von neuartigen keramischen Werkstoffen, mit denen sich der folgende Aufsatz des Instituts fuer Maschinenkonstruktionslehre und Kraftfahrzeugbau der Universitaet Karlsruhe naeher befasst. (orig.)

  3. Pedestrian injury mitigation by autonomous braking.

    Science.gov (United States)

    Rosén, Erik; Källhammer, Jan-Erik; Eriksson, Dick; Nentwich, Matthias; Fredriksson, Rikard; Smith, Kip

    2010-11-01

    The objective of this study was to calculate the potential effectiveness of a pedestrian injury mitigation system that autonomously brakes the car prior to impact. The effectiveness was measured by the reduction of fatally and severely injured pedestrians. The database from the German In-Depth Accident Study (GIDAS) was queried for pedestrians hit by the front of cars from 1999 to 2007. Case by case information on vehicle and pedestrian velocities and trajectories were analysed to estimate the field of view needed for a vehicle-based sensor to detect the pedestrians one second prior to the crash. The pre-impact braking system was assumed to activate the brakes one second prior to crash and to provide a braking deceleration up to the limit of the road surface conditions, but never to exceed 0.6 g. New impact speeds were then calculated for pedestrians that would have been detected by the sensor. These calculations assumed that all pedestrians who were within a given field of view but not obstructed by surrounding objects would be detected. The changes in fatality and severe injury risks were quantified using risk curves derived by logistic regression of the accident data. Summing the risks for all pedestrians, relationships between mitigation effectiveness, sensor field of view, braking initiation time, and deceleration were established. The study documents that the effectiveness at reducing fatally (severely) injured pedestrians in frontal collisions with cars reached 40% (27%) at a field of view of 40 degrees. Increasing the field of view further led to only marginal improvements in effectiveness. PMID:20728647

  4. MEMS for automotive and aerospace applications

    CERN Document Server

    Kraft, Michael

    2013-01-01

    MEMS for automotive and aerospace applications reviews the use of Micro-Electro-Mechanical-Systems (MEMS) in developing solutions to the unique challenges presented by the automotive and aerospace industries.Part one explores MEMS for a variety of automotive applications. The role of MEMS in passenger safety and comfort, sensors for automotive vehicle stability control applications and automotive tire pressure monitoring systems are considered, along with pressure and flow sensors for engine management, and RF MEMS for automotive radar sensors. Part two then goes on to explore MEMS for

  5. 新款三轮运动车制动系统设计%Design of Brake System of New Three-wheel Sports Car

    Institute of Scientific and Technical Information of China (English)

    田锐; 李桂华

    2012-01-01

    Through the braking performance analysis for new three-wheel sports car,the paper designed and calculated the structure of floating type disc brake in braking system and fully hydraulic braking drive system by human power.According to GB 7258-2004"safety specification for power-driven vehicles operating on road",its performance is verified,and the design result is good.And so the braking requirements of three-wheel sports car in ideal pavement is also met.%通过对新款三轮运动车制动性能要求进行分析,设计计算了制动系统的浮钳形盘式制动器结构和采用人力操纵的全液压制动驱动系统,并根据《机动车运行安全技术条件》(GB 7258-2004)进行了验证,达到了设计效果,满足了三轮运动车在理想路面上的制动要求。

  6. 汽车转向防抱死制动控制系统研究%Research on steering antilock braking control system for vehicles.

    Institute of Scientific and Technical Information of China (English)

    李果; 刘华伟

    2012-01-01

    为了研究解决车辆转向过程中防抱死制动稳定性问题,设计了一种由执行级、协调级组成的分层控制系统,在执行级,设计了基于遗传算法的汽车ABS最优滑模控制器;设计了基于遗传算法的汽车转向滑模控制器.在协调级,针对制动和转向两个子系统提出协调控制方案,给出具体协调策略.用仿真结果验证所设计控制算法的稳定性和有效性.%It is to study a new hierarchical intelligent control system in the vehicle's steering antilock brake stability fields. A layered control system consisting of the execution layer and the cooperation layer is designed. On the execution layer, optimal sliding mode controller based on genetic algorithms is designed for the automotive brake controller. Optimal sliding mode controller based on genetic algorithms is designed for the automotive steering controller. On the cooperation layer, this paper provides coordination control scheme and gives a specific coordination strategy for two subsystem of braking and steering. The stability and the validity of the control algorithm are validated by simulation results.

  7. Elemental composition of current automotive braking materials and derived air emission factors

    NARCIS (Netherlands)

    Hulskotte, J.H.J.; Roskam, G.D.; Denier van der Gon, H.A.C.

    2014-01-01

    Wear-related PM emissions are an important constituent of total PM emissions from road transport. Due to ongoing (further) exhaust emission reduction wear emissions may become the dominant PM source from road transport in the near future. The chemical composition of the wear emissions is crucial inf

  8. Effect of ZrSiO4 on the Friction Performance of Automotive Brake Friction Materials

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Friction-wear properties of the ZrSiO4 reinforced samples were measured and compared with those of plain bronze based ones. For this purpose, density, hardness, friction coefficient wear behaviour of the samples were tested. Microstructures of samples before and after sintering and worn surfaces were also investigated by scanning electron microscopy (SEM), and the wear types were determined. The optimum friction-wear behaviour was obtained in the sample compacted at 500 MPa and sintered at 820℃. Density of the final samples decreased with increasing the amount of reinforcing elements (ZrSiO4) before pre-sintering. However after sintering, there is no change in density of the samples including reinforcing elements (ZrSiO4). With increasing friction surface temperature, a reduction in the friction coefficient of the samples was observed.However, the highest reductions in the friction coefficients were observed in the as-received samples containing 0,5% reinforced ZrSiO4. The SEM images of the sample indicated that while bronze-based break lining material without ZrSiO4 showed abrasive wear behaviour, increasing the amount of ZrSiO4 resulted a change in abrasive to adhesive wear mechanism. All samples exhibited friction-wear values, which were within the values shown in SAE-J661 standard. With increasing the amount of reinforcing ZrSiO4, wear resistance of the samples was increased. However samples reinforced with 5% and 6% ZrSiO4 showed the best results.

  9. The vibration of rolling discs

    OpenAIRE

    Ferguson, Neil Stuart

    1988-01-01

    The study presented is a fundamental investigation into the vibration of a rolling disc and an analysis of the sound which is then produced by the disc response. In order to characterise the disc's behaviour the free and forced vibration of a thin disc is analysed with the additional conditions which occur in rolling. These conditions include the geometric boundary conditions, the effect of the in-plane load, the change due to rotation of the disc and the effect of contact on the disc which i...

  10. Pseudoenhancement of intervertebral disc herniation

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Y.; Ootani, M.; Furukawa, T.; Tsukaguchi, I. (Dept. of Radiology, Osaka Rosai Hospital (Japan)); Mitomo, M. (Dept. of Radiology, Osaka Univ. Medical School (Japan))

    1992-08-01

    Two patients with intervertebral disc herniation appeared to demonstrate abnormally diffuse and intense enhancement of the disc after intravenous administration of gadolinium-DTPA for MRI. Surgery disclosed a dilated epidural venous plexus in one and vascular granulation tissue in the other, associated with the herniated disc material. The mechanism of this 'pseudoenhancement' of the disc appears to be a partial volume effect of disc material and the adjacent veins or granulation tissue. Pseudoenhancement of a herniated disc should be included in the differential diagnosis of a diffusely enhancing epidural mass. (orig.).

  11. An Intelligent Regenerative Braking Strategy for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Zhibin Song

    2011-09-01

    Full Text Available Regenerative braking is an effective approach for electric vehicles (EVs to extend their driving range. A fuzzy-logic-based regenerative braking strategy (RBS integrated with series regenerative braking is developed in this paper to advance the level of energy-savings. From the viewpoint of securing car stability in braking operations, the braking force distribution between the front and rear wheels so as to accord with the ideal distribution curve are considered to prevent vehicles from experiencing wheel lock and slip phenomena during braking. Then, a fuzzy RBS using the driver’s braking force command, vehicle speed, battery SOC, battery temperature are designed to determine the distribution between friction braking force and regenerative braking force to improve the energy recuperation efficiency. The experimental results on an “LF620” prototype EV validated the feasibility and effectiveness of regenerative braking and showed that the proposed fuzzy RBS was endowed with good control performance. The maximum driving range of LF620 EV was improved by 25.7% compared with non-RBS conditions.

  12. Automotive Sensors and MEMS Technology

    Science.gov (United States)

    Nonomura, Yutaka

    - Automotive sensors are used for emission gas purification, energy conservation, car kinematic performance, safety and ITS (intelligent transportation system). The comparison of the sensor characteristics was made for their application area. Many kinds of the principles are applied for the sensors. There are two types of sensors, such as physical and chemical one. Many of the automotive sensors are physical type such as mechanical sensors. And a gas sensor is a chemical type. The sensors have been remarkably developed with the advancement of the MEMS (Micro Electro Mechanical Systems) technology. In this paper, gas, pressure, combustion pressure, acceleration, magnetic, and angular rate sensors for automotive use are explained with their features. The sensors are key devices to control cars in the engine, power train, chassis and safety systems. The environment resistance, long term reliability, and low cost are required for the automotive sensors. They are very hard to be resolved. However, the sensor technology contributes greatly to improving global environment, energy conservation, and safety. The applications of automotive sensors will be expanded with the automobile developments.

  13. 49 CFR 571.135 - Standard No. 135; Light vehicle brake systems.

    Science.gov (United States)

    2010-10-01

    ... the braking ratio of the vehicle. Antilock brake system or ABS means a portion of a service brake... neutral. (b) For an EV that is equipped with both ABS and RBS that is part of the service brake system, the ABS must control the RBS. S5.2. Parking brake system. Each vehicle shall be equipped with...

  14. Composition of Airy disc

    Institute of Scientific and Technical Information of China (English)

    Guoquan Zhou; Xiuxiang Chu; Jun Zheng

    2008-01-01

    The description of a plane wave diffracted by a circular aperture is directly started from the Maxwell's equations. Based on the vector angular spectrum representation of Maxwell's equations, the diffracted plane wave is decomposed into the TE and TM terms. The analytical TE and TM terms in the far field are presented by stationary phase. As the TE and TM terms are orthogonal to each other in the far field, their sum constitutes the so-called Airy disc pattern. Therefore, this research reveals the composition of Airy disc, which is beneficial to deepen and enhance the recognition of the classical diffraction problem.

  15. Supplier Selection in the Thai Automotive Industry

    OpenAIRE

    Nopprach, Somsupa

    2006-01-01

    This paper uses agglomeration theory to analyze the impact of Thai government policies on the development of the Thai automotive industry and cluster formation in Central and Eastern Thailand. Using cross-section data on 162 auto-parts suppliers from the Thailand Automotive Directory 2003-2004, the paper examines the criteria of supplier selection in the Thai automotive industry. Using logit models and cross-section data on 162 auto-parts suppliers from the Thailand Automotive Directory 2003-...

  16. Braking Resistor Scheme for Transient Stability Improvement

    Directory of Open Access Journals (Sweden)

    Saeed Abazari

    2007-09-01

    Full Text Available One of the most important problems in power systems design is increasing the damping of the swing amplitude and also to increase the critical time in transient stability. One of the best techniques is to use resistor braking. However, their performance in power systems, duration of their activity and their place of installation are of great importance. In this paper by using of some of devices in power electronics and by precies modeling of the network and optimal controller is designed which leads as to our final objective. In fact resistor braking are effectively attract additive energy which is a result of disturbances and help us to improve the stability of overall system.

  17. Wind turbine trailing edge aerodynamic brakes

    Energy Technology Data Exchange (ETDEWEB)

    Migliore, P G [National Renewable Energy Lab., Golden, CO (United States); Miller, L S [Wichita State Univ., KS (United States). Dept. of Aerospace Engineering; Quandt, G A

    1995-04-01

    Five trailing-edge devices were investigated to determine their potential as wind-turbine aerodynamic brakes, and for power modulation and load alleviation. Several promising configurations were identified. A new device, called the spoiler-flap, appears to be the best alternative. It is a simple device that is effective at all angles of attack. It is not structurally intrusive, and it has the potential for small actuating loads. It is shown that simultaneous achievement of a low lift/drag ratio and high drag is the determinant of device effectiveness, and that these attributes must persist up to an angle of attack of 45{degree}. It is also argued that aerodynamic brakes must be designed for a wind speed of at least 45 m/s (100 mph).

  18. Modeling of a Hydraulic Braking System

    OpenAIRE

    Lundin, Christopher

    2015-01-01

    The objective of this thesis is to derive an analytical model representing a reduced form of a mine hoist hydraulic braking system. Based primarily on fluid mechanical and mechanical physical modeling, along with a number of simplifying assumptions, the analytical model will be derived and expressed in the form of a system of differential equations including a set of static functions. The obtained model will be suitable for basic simulation and analysis of system dynamics, with the aim to cap...

  19. An Intelligent Auxiliary Vacuum Brake System

    OpenAIRE

    Tong, Chia-Chang; Lin, Jhih-Yu; Li, Shih-Fan; Li, Jiun-Yi

    2009-01-01

    The purpose of this paper focuses on designing an intelligent, compact, reliable, and robust auxiliary vacuum brake system (VBS) with Kalman filter and self-diagnosis scheme. All of the circuit elements in the designed system are integrated into one programmable system-on-chip (PSoC) with entire computational algorithms implemented by software. In this system, three main goals are achieved: (a) Kalman filter and hysteresis controller algorithms are employed within PSoC chip by software to sur...

  20. Bernoulli effect at free revolving flow braking

    OpenAIRE

    Budarin, V. A.

    2013-01-01

    In this research paper, analytical equations for the calculation of radial flow due to the braking on the flat surface plane of revolving flow were obtained. The calculation method is based on the use of pressure force balance equation, viscid friction and inertia. Three motion equations for incompressible, polytropic and isothermal flow were obtained, the type of a cumulative curve for the incompressible flow has been shown. Possibility of the use of radial flow for the compression of water ...

  1. Braking Resistor Scheme for Transient Stability Improvement

    OpenAIRE

    Saeed Abazari

    2007-01-01

    One of the most important problems in power systems design is increasing the damping of the swing amplitude and also to increase the critical time in transient stability. One of the best techniques is to use resistor braking. However, their performance in power systems, duration of their activity and their place of installation are of great importance. In this paper by using of some of devices in power electronics and by precies modeling of the network and optimal controller is designed which...

  2. Failure analysis in locomotive Bogie Brake-Hanger

    Directory of Open Access Journals (Sweden)

    NAVNEET SINGH1

    2012-05-01

    Full Text Available Breakage of brake riggings in WAP7 locomotives has been a matter of concern since 2004, almost afterits commencement of manufacturing, which is having same bogie design as that in WAG9 locomotives. Both ofthese bogies are having TBU/PBU assembly for brakes, but breakage of brake hangers in WAG9 locomotivesare unheard off. Both the inner as well as outer hangers are breaking. However, the cases of breakage of innerhangers towards bogie frame are much more with 80% of the total failures. This paper deliberates to understandthe various failures in locomotive Bogie Brake-Hanger and on root cause analysis for the failure of Brakehanger. In this paper we analyze the characteristics of brake hanger using FEA software.The goal of the project is to develop a high-speed train system capable of reaching the maximum speedand to secure its key technologies, one of which is the braking technology.

  3. Elastoplastic finite element analysis for wet multidisc brake during lasting braking

    Directory of Open Access Journals (Sweden)

    Ji Zhanling

    2015-01-01

    Full Text Available Addressed to serious heat degradation problem of the braking continuously performed in the drag brake application for a long time, finite element analysis for bidirectional thermal-structure coupling is adopted to investigate temperature and stress when material properties are temperature-dependent. Based on the constitutive relations of heat transfer and strain-stress, three-dimensional transient finite element equilibrium equations with many kinds of boundary conditions for bidirectional thermal-structure coupling were derived. And it was originally presented that start time, location, severity and evolution laws of plastic deformation were depicted using dimensionless stress distribution contour with the yield limit related to temperature. The change laws of plastic element number and contact area versus braking time were expressed by plasticity ratio and contact ratio curves, respectively. The laws revealed by the numerical calculation results are in accordance with the objective perception and reasoning.

  4. Spontaneously disappearing lumbar disc protrusion

    OpenAIRE

    Ushewokunze, Shungu; Abbas, Naeem; Dardis, Ronan; Killeen, Ian

    2008-01-01

    Spontaneous disappearance of a herniated lumbar disc is known to occur. This case study describes a 45-year-old patient whose symptoms of lumbar radiculopathy resolved and follow-up imaging showed complete disappearance of the disc prolapse. This phenomenon strengthens the role of conservative treatment in the management of lumbar disc protrusions.

  5. How do accretion discs break?

    Science.gov (United States)

    Dogan, Suzan

    2016-07-01

    Accretion discs are common in binary systems, and they are often found to be misaligned with respect to the binary orbit. The gravitational torque from a companion induces nodal precession in misaligned disc orbits. In this study, we first calculate whether this precession is strong enough to overcome the internal disc torques communicating angular momentum. We compare the disc precession torque with the disc viscous torque to determine whether the disc should warp or break. For typical parameters precession wins: the disc breaks into distinct planes that precess effectively independently. To check our analytical findings, we perform 3D hydrodynamical numerical simulations using the PHANTOM smoothed particle hydrodynamics code, and confirm that disc breaking is widespread and enhances accretion on to the central object. For some inclinations, the disc goes through strong Kozai cycles. Disc breaking promotes markedly enhanced and variable accretion and potentially produces high-energy particles or radiation through shocks. This would have significant implications for all binary systems: e.g. accretion outbursts in X-ray binaries and fuelling supermassive black hole (SMBH) binaries. The behaviour we have discussed in this work is relevant to a variety of astrophysical systems, for example X-ray binaries, where the disc plane may be tilted by radiation warping, SMBH binaries, where accretion of misaligned gas can create effectively random inclinations and protostellar binaries, where a disc may be misaligned by a variety of effects such as binary capture/exchange, accretion after binary formation.

  6. The Friction of Vehicle Brake Tandem Master Cylinder

    Science.gov (United States)

    Kao, M. J.; Chang, H.; Tsung, T. T.; Lin, H. M.

    2006-10-01

    The behaviour of an elastomeric seal for vehicle brake Tandem master cylinder is measured and analyzed in temperature and brake fluids changed. Working conditions are simulated for different piston rod velocity and cylinder supply pressure, in temperature rising, brakefluid boundary and Nanoaluminum oxide brakefluid oxide brakefluid lubrication. The result shows that Nanoaluminum oxide brakefluid with its ball shape can highly reduce friction coefficient to avoid seal excessive wear and reduce slick slip in brake applications.

  7. The Friction of Vehicle Brake Tandem Master Cylinder

    International Nuclear Information System (INIS)

    The behaviour of an elastomeric seal for vehicle brake Tandem master cylinder is measured and analyzed in temperature and brake fluids changed. Working conditions are simulated for different piston rod velocity and cylinder supply pressure, in temperature rising, brakefluid boundary and Nanoaluminum oxide brakefluid oxide brakefluid lubrication. The result shows that Nanoaluminum oxide brakefluid with its ball shape can highly reduce friction coefficient to avoid seal excessive wear and reduce slick slip in brake applications

  8. Tracing Planets in Circumstellar Discs

    Directory of Open Access Journals (Sweden)

    Uribe Ana L.

    2013-04-01

    Full Text Available Planets are assumed to form in circumstellar discs around young stellar objects. The additional gravitational potential of a planet perturbs the disc and leads to characteristic structures, i.e. spiral waves and gaps, in the disc density profile. We perform a large-scale parameter study on the observability of these planet-induced structures in circumstellar discs in the (submm wavelength range for the Atacama Large (SubMillimeter Array (ALMA. On the basis of hydrodynamical and magneto-hydrodynamical simulations of star-disc-planet models we calculate the disc temperature structure and (submm images of these systems. These are used to derive simulated ALMA maps. Because appropriate objects are frequent in the Taurus-Auriga region, we focus on a distance of 140 pc and a declination of ≈ 20°. The explored range of star-disc-planet configurations consists of six hydrodynamical simulations (including magnetic fields and different planet masses, nine disc sizes with outer radii ranging from 9 AU to 225 AU, 15 total disc masses in the range between 2.67·10-7 M⊙ and 4.10·10-2 M⊙, six different central stars and two different grain size distributions, resulting in 10 000 disc models. At almost all scales and in particular down to a scale of a few AU, ALMA is able to trace disc structures induced by planet-disc interaction or the influence of magnetic fields in the wavelength range between 0.4...2.0 mm. In most cases, the optimum angular resolution is limited by the sensitivity of ALMA. However, within the range of typical masses of protoplane tary discs (0.1 M⊙...0.001 M⊙ the disc mass has a minor impact on the observability. At the distance of 140 pc it is possible to resolve discs down to 2.67·10-6 M⊙ and trace gaps in discs with 2.67·10-4 M⊙ with a signal-to-noise ratio greater than three. In general, it is more likely to trace planet-induced gaps in magneto-hydrodynamical disc models, because gaps are wider in the presence of

  9. Effect of Titanium on the Mechanical Properties and Microstructure of Gray Cast Iron for Automotive Applications

    Science.gov (United States)

    Gelfi, M.; Gorini, D.; Pola, A.; La Vecchia, G. M.

    2016-07-01

    Lamellar gray cast iron, with a mainly pearlitic microstructure, is widely used in the automotive industry, mostly in the manufacturing of brake disks. This work analyzes in depth the effects of small variations of titanium content on the microstructure and mechanical properties of cast iron brake disks. For this purpose, eight different heats of EN-GJL-250 cast iron were selected, with a similar chemical composition but with different titanium contents, varying from 0.013 to 0.031%. The drops in mechanical strength and hardness values measured on the high-Ti samples were correlated to microstructural variations quantitatively observed by means of optical and scanning electron microscope. It was found that titanium combines to form titanium nitrides, suppressing the beneficial microstructural effects of nitrogen at solidification. Residual nitrogen, if present in sufficient quantity, promotes the nucleation of primary austenite from the liquid and the formation of a fine microstructure, with small eutectic cells and lower graphite content. Such a microstructure provides brake disks with better mechanical properties. The interpretation of results was further supported by thermal analysis and thermodynamic calculations.

  10. Evolution of Protoplanetary Discs with Magnetically Driven Disc Winds

    CERN Document Server

    Suzuki, Takeru K; Morbidelli, Alessandro; Crida, Aurélien; Guillot, Tristan

    2016-01-01

    Aims: We investigate the evolution of protoplanetary discs (PPDs hereafter) with magnetically driven disc winds and viscous heating. Methods: We consider an initially massive disc with ~0.1 Msun to track the evolution from the early stage of PPDs. We solve the time evolution of surface density and temperature by taking into account viscous heating and the loss of the mass and the angular momentum by the disc winds within the framework of a standard alpha model for accretion discs. Our model parameters, turbulent viscosity, disc wind mass loss, and disc wind torque, which are adopted from local magnetohydrodynamical simulations and constrained by the global energetics of the gravitational accretion, largely depends on the physical condition of PPDs, particularly on the evolution of the vertical magnetic flux in weakly ionized PPDs. Results: Although there are still uncertainties concerning the evolution of the vertical magnetic flux remaining, surface densities show a large variety, depending on the combinatio...

  11. Bryan total disc arthroplasty: a replacement disc for cervical disc disease

    OpenAIRE

    Wenger, Markus

    2010-01-01

    Markus Wenger1, Thomas-Marc Markwalder21Neurosurgery, Klinik Beau-Site and Salem-Spital, Berne, Switzerland; 2Attending Neurosurgeon FMH, Private Practice Spine Surgery, Berne-Muri, SwitzerlandAbstract: Total disc arthroplasty is a new option in the treatment of cervical degenerative disc disease. Several types of cervical disc prostheses currently challenge the gold-standard discectomy and fusion procedures. This review describes the Bryan Cervical Disc System and presents the Bryan prosthes...

  12. Compact Hybrid Automotive Propulsion System

    Science.gov (United States)

    Lupo, G.

    1986-01-01

    Power train proposed for experimental vehicle powered by internal combustion engine and electric motor. Intended for front-wheel drive automobile, power train mass produced using existing technology. System includes internal-combustion engine, electric motor, continuously variable transmission, torque converter, differential, and control and adjustment systems for electric motor and transmission. Continuously variable transmission integrated into hydraulic system that also handles power steering and power brakes. Batteries for electric motor mounted elsewhere in vehicle.

  13. Automotive Electronics. Teacher Edition (Revised).

    Science.gov (United States)

    Mackert, Howard C.; Heiserman, Russell L.

    This learning module addresses computers and their applications in contemporary automobiles. The text provides students with information on automotive microcomputers and hands-on activities that will help them see how semiconductors and digital logic devices fit into the modern repair facility. The module contains nine instructional units that…

  14. Automotive Technologies. State Competency Profile.

    Science.gov (United States)

    Ohio Board of Regents, Columbus.

    This document, which lists the technical automotive technologies competencies identified by representatives from business, industry, and labor as well as technical educators throughout Ohio, is intended to assist individuals and organizations in developing college tech prep programs that will prepare students from secondary through post-secondary…

  15. Human factors in automotive innovation

    NARCIS (Netherlands)

    Terken, J.; Ham, J.; Hoedemaeker, M.

    2011-01-01

    Many automotive innovations affect the driver's task and/or the driving experience. In this paper we argue that successful innovation in these cases requires that due attention is given to Human Factors issues in the course of the innovation process. We support this claim by examples from several re

  16. Innovative Technology in Automotive Technology

    Science.gov (United States)

    Gardner, John

    2007-01-01

    Automotive Technology combines hands-on training along with a fully integrated, interactive, computerized multistationed facility. Our program is a competency based, true open-entry/open-exit program that utilizes flexible self-paced course outlines. It is designed around an industry partnership that promotes community and economic development,…

  17. Automotive Cooling and Lubricating Systems.

    Science.gov (United States)

    Marine Corps Inst., Washington, DC.

    This correspondence course, originally developed for the Marine Corps, is designed to provide new mechanics with a source of study materials to assist them in becoming more proficient in their jobs. The course contains four study units covering automotive cooling system maintenance, cooling system repair, lubricating systems, and lubrication…

  18. A Model Predictive Control Allocation Approach to Hybrid Braking of Electric Vehicles

    OpenAIRE

    Satzger, Clemens; Pinto de Castro, Ricardo; Buente, Tilman

    2014-01-01

    With the recent emergence of electric drivetrains, a faster and energy efficient braking actuator - the electric motor - has become available to complement the operation of the traditional friction brakes. The decision on how to split the braking torque among the friction brake and the electric motor is one of the main issues of such hybrid braking systems. With this challenge in mind, a new model predictive control allocation (MPCA) approach for hybrid braking is proposed. In comparison to s...

  19. Research on Modeling and Control of Regenerative Braking for Brushless DC Machines Driven Electric Vehicles

    OpenAIRE

    Jian-ping Wen; Chuan-wei Zhang

    2015-01-01

    In order to improve energy utilization rate of battery-powered electric vehicle (EV) using brushless DC machine (BLDCM), the model of braking current generated by regenerative braking and control method are discussed. On the basis of the equivalent circuit of BLDCM during the generative braking period, the mathematic model of braking current is established. By using an extended state observer (ESO) to observe actual braking current and the unknown disturbances of regenerative braking system, ...

  20. Discs in misaligned binary systems

    CERN Document Server

    Rawiraswattana, Krisada; Goodwin, Simon P

    2016-01-01

    We perform SPH simulations to study precession and changes in alignment between the circumprimary disc and the binary orbit in misaligned binary systems. We find that the precession process can be described by the rigid-disc approximation, where the disc is considered as a rigid body interacting with the binary companion only gravitationally. Precession also causes change in alignment between the rotational axis of the disc and the spin axis of the primary star. This type of alignment is of great important for explaining the origin of spin-orbit misaligned planetary systems. However, we find that the rigid-disc approximation fails to describe changes in alignment between the disc and the binary orbit. This is because the alignment process is a consequence of interactions that involve the fluidity of the disc, such as the tidal interaction and the encounter interaction. Furthermore, simulation results show that there are not only alignment processes, which bring the components towards alignment, but also anti-...

  1. Assessment of Automotive Coatings Used on Different Metallic Substrates

    Directory of Open Access Journals (Sweden)

    W. Bensalah

    2014-01-01

    Full Text Available Four epoxy primers commonly used in the automotive industry were applied by gravity pneumatic spray gun over metallic substrates, specifically, steel, electrogalvanized steel, hot-dip galvanized steel, and aluminum. A two-component polyurethane resin was used as topcoat. To evaluate the performance of the different coating systems, the treated panels were submitted to mechanical testing using Persoz hardness, impact resistance, cupping, lattice method, and bending. Tribological properties of different coating systems were conducted using pin on disc machine. Immersion tests were carried out in 5% NaCl and immersion tests in 3% NaOH solutions. Results showed which of the coating systems is more suitable for each substrate in terms of mechanical, tribological, and anticorrosive performance.

  2. Disc-mass distribution in star-disc encounters

    CERN Document Server

    Steinhausen, M; Pfalzner, S

    2011-01-01

    Investigations of stellar encounters in cluster environments have demonstrated their potential influence on the mass and angular momentum of protoplanetary discs around young stars. In this study it is investigated in how far the initial surface density in the disc surrounding a young star influences the outcome of an encounter. Based on a power-law ansatz for the surface density, $\\Sigma(r) \\propto r^{-p}$, a parameter study of star-disc encounters with different initial disc-mass distributions has been performed using N-body simulations. It is demonstrated that the shape of the disc-mass distribution has a significant impact on the quantity of the disc-mass and angular momentum losses in star-disc encounters. Most sensitive are the results where the outer parts of the disc are perturbed by high-mass stars. By contrast, disc-penetrating encounters lead more or less independently of the disc-mass distribution always to large losses. However, maximum losses are generally obtained for initially flat distributed...

  3. Speciation of Sb in airborne particulate matter, vehicle brake linings, and brake pad wear residues

    Science.gov (United States)

    Varrica, D.; Bardelli, F.; Dongarrà, G.; Tamburo, E.

    2013-01-01

    Insights into the speciation of Sb in samples of brake linings, brake pad wear residues, road dust, and atmospheric particulate matter PM10 and PM2.5 were obtained combining several well established and advanced characterization techniques, such as scanning electron microscopy - energy dispersive spectrometry (SEM-EDS), inductively coupled plasma mass spectrometry (ICP-MS) and synchrotron radiation X-ray absorption spectroscopy (SR-XAS). The advantage of SR-XAS is that samples do not undergo any chemical treatment prior to measurements, thus excluding possible alterations. These analyses revealed that the samples of wheel rims dust, road dust, and atmospheric particulate matter are composed by an admixture of Sb(III) and Sb(V) in different relative abundances. Brake linings turned out to be composed by Sb(III) oxide (Sb2O3) and stibnite (Sb2S3). Stibnite was also detected in some of the particulate matter samples. The obtained data suggest that Sb2S3 during the brake abrasion process is easily decomposed forming more stable compounds such as antimony mixed oxidic forms. Sb redox speciation, in particular and well studied circumstances, may enhance the potential and selectivity of this element as a tracer of motor vehicle emissions in apportioning studies.

  4. Mapping automotive like controls to a general aviation aircraft

    Science.gov (United States)

    Carvalho, Christopher G.

    The purpose of this thesis was to develop fly-by-wire control laws enabling a general aviation aircraft to be flown with automotive controls, i.e. a steering wheel and gas/brake pedals. There was a six speed shifter used to change the flight mode of the aircraft. This essentially allows the pilot to have control over different aspects of the flight profile such as climb/descend or cruise. A highway in the sky was used to aid in the navigation since it is not intuitive to people without flight experience how to navigate from the sky or when to climb and descend. Many believe that general aviation could become as widespread as the automobile. Every person could have a personal aircraft at their disposal and it would be as easy to operate as driving an automobile. The goal of this thesis is to fuse the ease of drivability of a car with flight of a small general aviation aircraft. A standard automotive control hardware setup coupled with variably autonomous control laws will allow new pilots to fly a plane as easily as driving a car. The idea is that new pilots will require very little training to become proficient with these controls. Pilots with little time to stay current can maintain their skills simply by driving a car which is typically a daily activity. A human factors study was conducted to determine the feasibility of the applied control techniques. Pilot performance metrics were developed to compare candidates with no aviation background and experienced pilots. After analyzing the relative performance between pilots and non-pilots, it has been determined that the control system is robust and easy to learn. Candidates with no aviation experience whatsoever can learn to fly an aircraft as safely and efficiently as someone with hundreds of hours of flight experience using these controls.

  5. Total disc replacement.

    Science.gov (United States)

    Vital, J-M; Boissière, L

    2014-02-01

    Total disc replacement (TDR) (partial disc replacement will not be described) has been used in the lumbar spine since the 1980s, and more recently in the cervical spine. Although the biomechanical concepts are the same and both are inserted through an anterior approach, lumbar TDR is conventionally indicated for chronic low back pain, whereas cervical TDR is used for soft discal hernia resulting in cervicobrachial neuralgia. The insertion technique must be rigorous, with precise centering in the disc space, taking account of vascular anatomy, which is more complex in the lumbar region, particularly proximally to L5-S1. All of the numerous studies, including prospective randomized comparative trials, have demonstrated non-inferiority to fusion, or even short-term superiority regarding speed of improvement. The main implant-related complication is bridging heterotopic ossification with resulting loss of range of motion and increased rates of adjacent segment degeneration, although with an incidence lower than after arthrodesis. A sufficiently long follow-up, which has not yet been reached, will be necessary to establish definitively an advantage for TDR, particularly in the cervical spine. PMID:24412045

  6. Apsidal precession, disc breaking and viscosity in warped discs

    CERN Document Server

    Nealon, Rebecca; Price, Daniel J; King, Andrew

    2015-01-01

    We demonstrate the importance of general relativistic apsidal precession in warped black hole accretion discs by comparing three - dimensional smoothed particle hydrodynamic simulations in which this effect is first neglected, and then included. If apsidal precession is neglected, we confirm the results of an earlier magnetohydrodynamic simulation which made this assumption, showing that at least in this case the $\\alpha$ viscosity model produces very similar results to those of simulations where angular momentum transport is due to the magnetorotational instability. Including apsidal precession significantly changes the predicted disc evolution. For moderately inclined discs thick enough that tilt is transported by bending waves, we find a disc tilt which is nonzero at the inner disc edge and oscillates with radius, consistent with published analytic results. For larger inclinations we find disc breaking.

  7. 49 CFR 570.5 - Service brake system.

    Science.gov (United States)

    2010-10-01

    ...) Friction materials. On each brake the thickness of the lining or pad shall not be less than one thirty... CFR 571.105, on every new passenger car manufactured on or after January 1, 1968, and on other types... from loose material, oil, or grease. The service brakes shall be applied at a vehicle speed of 20...

  8. 49 CFR 570.59 - Service brake system.

    Science.gov (United States)

    2010-10-01

    ...) Friction materials. On each brake, the thickness of the lining or pad shall not be less than one thirty-second of an inch over the fastener, or one-sixteenth of an inch over the brake shoe on bonded linings or... percent grade), dry, smooth, hard-surfaced road that is free from loose material, oil or grease....

  9. 16 CFR 306.10 - Automotive fuel rating posting.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Automotive fuel rating posting. 306.10... AUTOMOTIVE FUEL RATINGS, CERTIFICATION AND POSTING Duties of Retailers § 306.10 Automotive fuel rating posting. (a) If you are a retailer, you must post the automotive fuel rating of all automotive fuel...

  10. Planet-Disc Interactions in Fully Radiative Discs

    OpenAIRE

    Bitsch, Bertram

    2011-01-01

    In this dissertation the movement of planets in accretion discs surrounding young stars is investigated. The accretion disc surrounds a protostar, which in turn is created due to the gravitational collapse of an interstellar gas cloud. In this accretion disc, small dust particles can grow to larger objects with a size of up to a few kilometers. These objects are called planetesimals. Through collisions, these planetesimals can grow further until they reach the size of a protoplanet. The proto...

  11. Disc-planet interactions in sub-keplerian discs

    OpenAIRE

    Paardekooper, S.-J.

    2009-01-01

    One class of protoplanetary disc models, the X-wind model, predicts strongly subkeplerian orbital gas velocities, a configuration that can be sustained by magnetic tension. We investigate disc-planet interactions in these subkeplerian discs, focusing on orbital migration for low-mass planets and gap formation for high-mass planets. We use linear calculations and nonlinear hydrodynamical simulations to measure the torque and look at gap formation. In both cases, the subkeplerian nature of the ...

  12. Design of haptic master featuring small-sized MR brakes

    Science.gov (United States)

    Gang, Han Gyeol; Choi, Seung-Bok; Sohn, Jung Woo

    2016-04-01

    In this work, a new type of haptic master featuring small-sized MR brake is proposed and its performances are evaluated. The proposed haptic master consists of base frame, stick grip and small-sized four MR brakes for 3-DOF rotational motion and 1-DOF gripper motion. To obtain large braking torque under limited small size of MR brake, dual tapered shape inner magnetic core is proposed and its performance is evaluated via both numerical estimation and experimental test. After design and implementation of control algorithm, it has been demonstrated through experiment that the proposed actuator has good performances on tracking control of desired torques. Then, a new haptic master device is designed and constructed by adopting the proposed MR brakes and light weight frame structures. It is verified that the proposed haptic master device is effective for the real application in the field.

  13. Development of Asbestos - Free Brake Pad Using Bagasse

    Directory of Open Access Journals (Sweden)

    V. S. Aigbodion

    2010-03-01

    Full Text Available Development of asbestos-free brake pad using bagasse was investigated with a view to replace the use of asbestos whose dust is carcinogenic. The bagasse were sieve into sieve grades of 100, 150, 250, 350 and 710µm. the sieve bagasse was used in production of brake pad in ratio of 70%bagasse-30%resin using compression moulding. The properties examined are microstructure analysis, hardness, compressive strength, density, flame resistance, water and oil absorption. The microstructure reveals uniform distribution of resin in the bagasse. The results obtained showed that the finer the sieve size the better the properties. The results obtained in this work were compared with that of commercial brake pad (asbestos based and optimum formulation laboratory brake pad Palm Kernel Shell based (PKS, the results are in close agreement. Hence bagasse can be used in production of asbestos-free brake pad.

  14. Study of the interaction between microstructure, mechanical and tribo-performance of a commercial brake lining material

    International Nuclear Information System (INIS)

    Highlights: • Interdependencies between the performance influencing parameters are established. • The constituents role is influenced by the heterogeneity of the friction material. • The anisotropy of the material depends essentially on the fiber orientation. • The ability of fibers to participate on load-bearing depends on their orientations. - Abstract: The interaction between microstructure, mechanical, and frictional properties of a commercial brake lining material (BLM) was investigated in order to correlate them to braking performance. For this purpose, a Scanning Electron Microscope (SEM) with energy dispersive X-ray (EDX) mapping and spectrum were used to identify and analyze different constituents. The mechanical properties were determined using compression test. Relevant physical properties (density and porosity) were determined using standard test methods. The friction coefficient and wear behavior of the friction material on contact with the grey cast iron disc were established using a pad-on disc tribometer. The results have shown that the brake lining material contains phenol resin such as the matrix and other various ingredients, including silica, rock and mineral filler reinforcement, barium sulfate and carbon-rich particles as filler and brass particles as friction modifier. It had a varied amount and size up to 1 mm for brass particles. The density and porosity were 1.8 g cm−3 and 7%, respectively. The investigated material exhibited excellent mechanical properties in the normal solicitation direction. The average friction coefficient was about 0.65, whereas the friction coefficient was stable. The different actions of various ingredients in terms of their effects on the friction and wear behavior of the BLM could be related to their different bonding strengths with the resin matrix and their different abilities to form friction films (third-body layer) on the surfaces of the material and transfer films on the counterpart cast iron

  15. GLOBAL PERSPECTIVES IN AUTOMOTIVE INDUSTRY

    Directory of Open Access Journals (Sweden)

    NICOLETA ISAC

    2010-01-01

    Full Text Available The automotive sector is characterised by a relatively low trade/salesratio. While the production of most automotive producers in the world is spread over variouscountries in the value chain, the brands are still considered to reflect some national identity.Internationalisation strategies may change over the lifecycle of the product and automakerstend to pursue diametrically opposed strategies. In mature markets, it is about managing whatgoes on beneath a static surface; in emerging markets’ dynamic environments, companies muststrategically position themselves to benefit from growth opportunities. However, without theright strategy and execution in mature markets, it is clear that traditional OEMs cannot profitfrom emerging markets-the persistence of structural issues in mature market operationseventually will rob all but the most resilient competitors of the opportunity to compete inemerging markets.

  16. Antenna Arrays and Automotive Applications

    CERN Document Server

    Rabinovich, Victor

    2013-01-01

    This book throws a lifeline to designers wading through mounds of antenna array patents looking for the most suitable systems for their projects. Drastically reducing the research time required to locate solutions to the latest challenges in automotive communications, it sorts and systematizes material on cutting-edge antenna arrays that feature multi-element communication systems with enormous potential for the automotive industry. These new systems promise to make driving safer and more efficient, opening up myriad applications, including vehicle-to-vehicle traffic that prevents collisions, automatic toll collection, vehicle location and fine-tuning for cruise control systems. This book’s exhaustive coverage begins with currently deployed systems, frequency ranges and key parameters. It proceeds to examine system geometry, analog and digital beam steering technology (including "smart" beams formed in noisy environments), maximizing signal-to-noise ratios, miniaturization, and base station technology that ...

  17. Advanced Materials for Automotive Application

    International Nuclear Information System (INIS)

    In this paper some recent material developments will be overviewed mainly from the point of view of automotive industry. In car industry, metal forming is one of the most important manufacturing processes imposing severe restrictions on materials; these are often contradictory requirements, e.g. high strength simultaneously with good formability, etc. Due to these challenges and the ever increasing demand new material classes have been developed; however, the more and more wide application of high strength materials meeting the requirements stated by the mass reduction lead to increasing difficulties concerning the formability which requires significant technological developments as well. In this paper, the recent materials developments will be overviewed from the point of view of the automotive industry

  18. Edge-on thick discs

    Science.gov (United States)

    Kasparova, A.; Katkov, I.; Chilingarian, I.; Silchenko, O.; Moiseev, A.; Borisov, S.

    2016-06-01

    Although thick stellar discs are detected in nearly all edge-on disc galaxies, their formation scenarios still remain a matter of debate. Due to observational difficulties, there is a lack of information about their stellar populations. Using the Russian 6-m telescope BTA we collected deep spectra of thick discs in three edge-on early-type disc galaxies located in different environments: NGC4111 in a dense group, NGC4710 in the Virgo cluster, and NGC5422 in a sparse group. We see intermediate age (4 ‑ 5 Gyr) metal rich ([Fe/H] ~ ‑0.2 ‑ 0.0 dex) stellar populations in NGC4111 and NGC4710. On the other hand, NGC5422 does not harbour young stars, its only disc is thick and old (10 Gyr) and its α-element abundance suggests a long formation epoch implying its formation at high redshift. Our results prove the diversity of thick disc formation scenarios.

  19. CT discography for cervical soft disc hernia

    International Nuclear Information System (INIS)

    In this study the effectiveness of computed tomographic discography (CTD) in diagnosing cervical soft disc hernia was evaluated. Twenty-five interververtebral discs of 15 cases with cervical soft disc hernia were examined with a discography and then a CT scan. Results of the CT scan were as follows: three discs were protruded, 12 discs were prolapsed, 6 discs were extruded, and 4 discs were sequestrated. The findings were helpful in determining the location of soft disc hernians between the median and posterolateral discs. They were also valuable in classifying types of hernians and surgical aproaches. (author)

  20. Rejuvenation of automotive fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Seung; Langlois, David A.

    2016-08-23

    A process for rejuvenating fuel cells has been demonstrated to improve the performance of polymer exchange membrane fuel cells with platinum/ionomer electrodes. The process involves dehydrating a fuel cell and exposing at least the cathode of the fuel cell to dry gas (nitrogen, for example) at a temperature higher than the operating temperature of the fuel cell. The process may be used to prolong the operating lifetime of an automotive fuel cell.

  1. Automotive stamped part fatigue design

    OpenAIRE

    Caudoux Mélanie; Facchinetti Matteo Luca; Raynal Renaud

    2014-01-01

    Fatigue design of automotive axle parts is of prior concern because of these are high safety parts and they are expected to drive the overall vehicle mass reduction. In this framework, the stamping process is widely used to form axle parts, before assembling them by welding. Consequently, the mechanical and physical characteristics of the blank sheet are modified, having a strong influence on the fatigue behavior. In this paper, we address the consequences of the stamped process on the fatigu...

  2. Computational intelligence in automotive applications

    Energy Technology Data Exchange (ETDEWEB)

    Prokhorov, Danil (ed.) [Toyota Motor Engineering and Manufacturing (TEMA), Ann Arbor, MI (United States). Toyota Technical Center

    2008-07-01

    What is computational intelligence (CI)? Traditionally, CI is understood as a collection of methods from the fields of neural networks (NN), fuzzy logic and evolutionary computation. This edited volume is the first of its kind, suitable to automotive researchers, engineers and students. It provides a representative sample of contemporary CI activities in the area of automotive technology. The volume consists of 13 chapters, including but not limited to these topics: vehicle diagnostics and vehicle system safety, control of vehicular systems, quality control of automotive processes, driver state estimation, safety of pedestrians, intelligent vehicles. All chapters contain overviews of state of the art, and several chapters illustrate their methodologies on examples of real-world systems. About the Editor: Danil Prokhorov began his technical career in St. Petersburg, Russia, after graduating with Honors from Saint Petersburg State University of Aerospace Instrumentation in 1992 (MS in Robotics). He worked as a research engineer in St. Petersburg Institute for Informatics and Automation, one of the institutes of the Russian Academy of Sciences. He came to the US in late 1993 for Ph.D. studies. He became involved in automotive research in 1995 when he was a Summer intern at Ford Scientific Research Lab in Dearborn, MI. Upon his graduation from the EE Department of Texas Tech University, Lubbock, in 1997, he joined Ford to pursue application-driven research on neural networks and other machine learning algorithms. While at Ford, he took part in several production-bound projects including neural network based engine misfire detection. Since 2005 he is with Toyota Technical Center, Ann Arbor, MI, overseeing important mid- and long-term research projects in computational intelligence. (orig.)

  3. Noise Radiation from Automotive Turbochargers

    OpenAIRE

    Zhenrui, Wang

    2011-01-01

    Turbochargers are now commonly used in modern automotive engines, which increase the density of air entering the engine to produce more power. This device not only greatly improves the degree of engine efficiency, but also reduces the pollutant emissions. However, one of the important issues which must be considered is the noise from turbochargers. This noise can radiate either after propagation through the intake and exhaust ducts or via induced vibrations in the turbocharger housing. Here t...

  4. CAE ANALYSIS OF AUTOMOTIVE LAMP

    OpenAIRE

    Vaibhav Wakchaure*; G.V.R Seshagiri Rao

    2015-01-01

    This Paper work is focused on the different FE analysis performed for the automotive lamps. Front fog lamp is designed according to the mounting position given in the panel and the light output requirement. In this paper different type of CAE analysis performed to qualify the physical test requirement the objective of this analysis is to find the optimum size design of lamp to qualify the test & output as per customer requirement. In this paper Static, vibration & fatigue analysis...

  5. Applications of thin coatings in automotive industry

    Directory of Open Access Journals (Sweden)

    P. Louda

    2007-09-01

    Full Text Available Purpose: Use of thin coatings in automotive industry give economic and ecological savings. This is evoke by reducing of weight of used construction elements and currently by increasing of their service life and with that connected elevating of nanomaterials manufacture qualities.Design/methodology/approach: In the paper was disscussed the possibility of applications of thin coating in automotive industry.Findings: The paper shows the examples of thin coatings application in automotive industry.Practical implications: Through the assimilation, improvement, and generation of new technologies, the coating community, as a major supplier to the very large automotive industry, will continue to thrive, grow, and maintain its environmental stewardship in the global marketplace.Originality/value: Applications of thin coatings in automotive industry is and with nanotechnology together will be in centre of interest of automotive industry in near future.

  6. An Investigation into the Behavior of Disc Blake Wear

    Directory of Open Access Journals (Sweden)

    Muneer A. H.Jassim

    2007-01-01

    Full Text Available A real method of predication brake pad wear ,could lead to substantiol economies of time and money. This paper describes how such a procedure has been used and gives the results to establish is reliability by comparing the predicted wear with that which actually occurs in an existing service. The experimental work was carried out on three different commercial samples ,tested under different operation conditions (speed,load,time...etcusing a test ring especially modified for this purpose. Abrasive wear is mainly studied , since it is the type of wear that takes place in such arrangements. Samples wear tested in presences of sand or mud between the mating surfaces under different operational conditions of speed, load and braking time .Mechanical properties of the pad material samples (hardness, young,s modulus and collapse load under pure bending condition wear established . The thermal conductivity and surface roughness of the pad material wear also found in order to enable comparison between the surface condition before and after testing. Sliding velocity had a small effect on the wear rate but it had great effect on friction coefficient. Wear rate was affected mainly by the surface temperature which causing a reduction friction coefficient and increasing the wear rate. Surface roughness had almost no effect on the wear rate since it was proved experimentally ,that the surface becomes softer during operation .mechanical properties of the pad material had fluctuating effect on wear rate. The existence of solid particles between pad and disc increasing wear rate and friction coefficient while the mud caused a reduction in wear rate of the pad surface since it acts as a lubricant absorbing the surface heat generated during sliding the area of contact between pad and disc. wear rate obtained experimentally agreed fairly well that found from empirically obtained equations.

  7. Simulation based design of automotive systems

    OpenAIRE

    Schiehlen, Werner

    1993-01-01

    The design of automotive systems using simulation tools features cost reduction and quality enhancement. This paper presents two basic approaches. The rust approach deals with the application of CAD data bases to the evaluation of input data for multibody system formalisms, most adequate for automotive system modeling. An object oriented data model for multibody systems is presented. The second approach covers the development of an integrated simulation tool for automotive vehicles and the co...

  8. Applications of thin coatings in automotive industry

    OpenAIRE

    P. Louda

    2007-01-01

    Purpose: Use of thin coatings in automotive industry give economic and ecological savings. This is evoke by reducing of weight of used construction elements and currently by increasing of their service life and with that connected elevating of nanomaterials manufacture qualities.Design/methodology/approach: In the paper was disscussed the possibility of applications of thin coating in automotive industry.Findings: The paper shows the examples of thin coatings application in automotive industr...

  9. Systems thinking in designing automotive textiles

    OpenAIRE

    Sinha, Pammi; Muthu, Subramanian Senthilkannan; Taylor, Iain; Schulz, Rita; Beverley, Katharine J.; Day, Claire L.; Tipi, Nicoleta S.

    2015-01-01

    We present the complexities in terms of designing automotive exterior seating materials (seat coverings and interior linings) at Sage Automotive Interiors (UK), which is a division of a global international automotive textile supplier with headquarters in the US. Sustainability and innovation are emphasized in documents communicating the company’s vision. Using a case study approach, we consider the current design, development and manufacture process and examine it for the potential for feedb...

  10. Relativistic Disc lines

    CERN Document Server

    Fabian, A C; Parker, M L

    2014-01-01

    Broad emission lines, particularly broad iron-K lines, are now commonly seen in the X-ray spectra of luminous AGN and Galactic black hole binaries. Sensitive NuSTAR spectra over the energy range of 3-78 keV and high frequency reverberation spectra now confirm that these are relativistic disc lines produced by coronal irradiation of the innermost accretion flow around rapidly spinning black holes. General relativistic effects are essential in explaining the observations. Recent results are briefly reviewed here.

  11. 49 CFR 236.554 - Rate of pressure reduction; equalizing reservoir or brake pipe.

    Science.gov (United States)

    2010-10-01

    ... or brake pipe. 236.554 Section 236.554 Transportation Other Regulations Relating to Transportation...; Locomotives § 236.554 Rate of pressure reduction; equalizing reservoir or brake pipe. The equalizing-reservoir pressure or brake-pipe pressure reduction during an automatic brake application shall be at a rate not...

  12. 49 CFR 571.121 - Standard No. 121; Air brake systems.

    Science.gov (United States)

    2010-10-01

    ... brakes. Antilock brake system or ABS means a portion of a service brake system that automatically... reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the material may be inspected at... control lines and reservoirs that minimizes damage in field operations. Air brake system means a...

  13. Percutaneous laser disc decompression for cervical disc herniation

    International Nuclear Information System (INIS)

    Objective: To discuss the clinical application of percutaneous laser disc decompression (PLDD) in the treatment of cervical disc herniation. Methods: The region between anterolateral cervical visceral sheath and carotid sheath was used as puncture access. Under C-arm fluoroscopic monitoring, the puncture needle was inserted to the cervical intervertebral space center, then, the photofiber was implanted in PLDD was performed in 32 patients of cervical disc herniation by using SLT30 semiconductor laser device with the laser output of 500-1 000 J. Results: The effective rate was 87.5%. No infection or serious complications occurred. Conclusion: Percutaneous laser disc decompression is a safe, effective and less invasive treatment for cervical disc herniation. (authors)

  14. Research on Modeling and Control of Regenerative Braking for Brushless DC Machines Driven Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jian-ping Wen

    2015-01-01

    Full Text Available In order to improve energy utilization rate of battery-powered electric vehicle (EV using brushless DC machine (BLDCM, the model of braking current generated by regenerative braking and control method are discussed. On the basis of the equivalent circuit of BLDCM during the generative braking period, the mathematic model of braking current is established. By using an extended state observer (ESO to observe actual braking current and the unknown disturbances of regenerative braking system, the autodisturbances rejection controller (ADRC for controlling the braking current is developed. Experimental results show that the proposed method gives better recovery efficiency and is robust to disturbances.

  15. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... over, you know, fusion. People wonder, does it cause problems at the next level up, so if ... a concern. Will the fusion at this disc cause problems at the disc above or the disc ...

  16. 46 CFR 64.61 - Rupture disc.

    Science.gov (United States)

    2010-10-01

    ... SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.61 Rupture disc. If a rupture disc is the only pressure relief device on the tank, the rupture disc must— (a) Rupture at a pressure...

  17. Finite element analysis of advanced bicycle precision brake disk forming technology

    Directory of Open Access Journals (Sweden)

    Chen Dyi-Cheng

    2015-01-01

    Full Text Available In recent years, the bicycle has become an environmentally friendly transportation. The bicycle can be divided into mountain bicycle and highway bicycle. Safe driving is the prior consideration. The bicycle braking system can be divided into oil pressure disk brakes and mechanical disk brakes. The brake disk system is one indispensable component of the safe system. In accordance to overall weight consideration of the bike, the brake disk should also focus on the lightweight design. This paper discussed an innovative brake disk forming technology for 6061 aluminum alloy by the rigid-plastic finite element analysis. The simulation parameters include geometric shapes of the brake disk and mold, die temperature, and friction factors. The stress and strain in forming, brake deformation and vibration modal analysis of brake disk in riding were studied. The paper is expected to offer some precision bicycle brake disk manufacture knowledge for industry.

  18. 8th DFO Automotive conference - European automotive coating

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The present CD-ROM of the DFO Conference ''European Automotive Coating'' held on the 14th and 15th May 2001 in Dresden, Germany, contents the following contributions: Contents (1) Plenary Lecture-Car Body Painting in the Digital Factory (2) Off-line painting of a smc Oe tailgate in topcoat colour; (3) Twincure UV - New Concepts for the Surface Treatment of Glass-Fiber-Reinforced; Plastics; (4) New Concepts for Exterior Coating - ''Funktionsschicht 3'' First Experiences and the ''Ludwigsfelde Concept''; (5) Application techniques in the light of new automation concepts in automotive painting; (6) Automatic Management System for Car Body Pretreatment; (7) Surface Inspection on Bodies in White in Automotive Industry; (8) Online Measurement and Control of E-coat Bath Parameters in a Car Body Paint Shop - Development until Maturity for Manufacturing - Practical Experiences; (9) Automated Process Diagnosis; (10) Wavescan DOI Oe Challenge or Data Overkill; (11) Robot Aided Online Metrology for Quality Assurance and Process Control of Coated Surfaces; (12) Physical Simulation of Film Thickness Distribution and Transfer Efficiency in the Electrostatically Supported Painting process; (13) Offline Simulation of the Coating Process with High-Speed Bell and Pneumatic Atomizers; (14) Top coat simulation - First applications and results; (15) Virtual color design. (AKF) (orig.) [German] Die vorliegende zweisprachige (Deutsch/Englisch) CD-ROM der DFO-Tagung ''European Automotive Coating'' vom 14. und 15. Mai 2001 beinhaltet die folgenden Beitraegen: Inhaltsverzeichnis (1) Leitvortrag ''Die Automobillackierung in der digitalen Fabrik''; (2) Off-line Lackierung von SMC-Heckklappen in Decklackfarbe; (3) Hybrid UV-Haertung - Neue Konzepte zur Oberflaechenveredelung von glasfaserverstaerkten Duroplasten; (4) Neue Konzepte fuer die Aussenhautlackierung - Fukntionsschicht 3 - Erste

  19. Retardation-controlled safety brake at the test site

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, A.; Schroeder, R.; Sondermann, W.

    1989-02-01

    A double-drum winding installation is thought to require a retardation-controlled safety brake. The investigations needed for the design acceptance of such a braking installation have so far only been possible on an actual winding installation. This has not ruled out that the commissioning procedure of the whole installation could be delayed or endangered. The use of a simulator developed by the WBK Rope Testing Station, which replicates the behaviour of braked masses in the winding installation, made it possible for the first time to transfer a major part of the necessary investigations to the test site.

  20. MODIFICATION OF FLAKE REINFORCED FRICTION BRAKE COMPOSITE MATERIAL

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    According to the recent development trend and need of the friction brake material, the flake reinforced friction brake material has been made out by adjusting the recipe and techniques. The two-dimensional flake vermiculite is selected as the reinforced stuffing of the material; the modified resin is used as the basal bed of the material. The tests manifest that the properties of mechanics are high, the friction coefficients are suitable and stable,and especially in high temperatures the wear is low. It is an excellent friction brake material.

  1. New Phase-coherent Measurements of Pulsar Braking Indices

    CERN Document Server

    Livingstone, M A; Gavriil, F P; Manchester, R N; Gotthelf, E V; Kuiper, L; Livingstone, Margaret A.; Kaspi, Victoria M.; Gavriil, Fotis P.; Manchester, Richard N.; Kuiper, Lucien

    2007-01-01

    Pulsar braking indices offer insight into the physics that underlies pulsar spin-down. Only five braking indices have been measured via phase-coherent timing; all measured values are less than 3, the value expected from magnetic dipole radiation. Here we present new measurements for three of the five pulsar braking indices, obtained with phase-coherent timing for PSRs J1846-0258 (n=2.65+/-0.01), B1509-58 (n=2.839+/-0.001) and B0540-69 (n=2.140+/-0.009). We discuss the implications of these results and possible physical explanations for them.

  2. Gravitational waves from pulsars with measured braking index

    CERN Document Server

    de Araujo, Jose C N; Costa, Cesar A

    2016-01-01

    We study the putative emission of gravitational waves (GWs) in particular for pulsars with measured braking index. We show that the appropriate combination of both GW emission and magnetic dipole brakes can naturally explain the measured braking index, when the surface magnetic field and the angle between the magnetic dipole and rotation axes are time dependent. Then we discuss the detectability of these very pulsars by aLIGO and the Einstein Telescope. We call attention to the realistic possibility that aLIGO can detect the GWs generated by at least some of these pulsars, such as Vela, for example.

  3. Cycling and wind: does sidewind brake?

    International Nuclear Information System (INIS)

    It is well established that the presence of wind is crucial for the practice of numerous outdoor sports. Among them, the case of cycling competition is especially important because the speeds that are developed are perfectly comparable with moderate or strong winds, giving rise to great variability in race times. Conversely, the sidewind seems to behave as neutral in the race, and nevertheless all the cyclists know the difficulties that it causes. In this brief paper we show that the sidewind also produces an appreciable braking as a consequence of the quadratic dependence of the aerodynamic drag force on the air speed. Our work presents an interesting problem of mechanics and physics of fluids, which may be suitable as a task for intermediate level students in university courses

  4. A Pulsar Eases Off the Brakes

    Science.gov (United States)

    Kohler, Susanna

    2015-10-01

    In 2006, pulsar PSR 18460258 unexpectedly launched into a series of energetic X-ray outbursts. Now a study has determined that this event may have permanently changed the behavior of this pulsar, raising questions about our understanding of how pulsars evolve.Between CategoriesA pulsar a highly magnetized, rotating neutron star that emits a beam of electromagnetic radiation can be powered by one of three mechanisms:Rotation-powered pulsars transform rotational energy into radiation, gradually slowing down in a predictable way.Accretion-powered pulsars convert the gravitational energy of accreting matter into radiation.Magnetars are powered by the decay of their extremely strong magnetic fields.Astronomical classification often results in one pesky object that doesnt follow the rules. In this case, that object is PSR 18460258, a young pulsar categorized as rotation-powered. But in 2006, PSR 18460258 suddenly emitted a series of short, hard X-ray bursts and underwent a flux increase behavior that is usually only exhibited by magnetars. After this outburst, it returned to normal, rotation-powered-pulsar behavior.Since the discovery of this event, scientists have been attempting to learn more about this strange pulsar that seems to straddle the line between rotation-powered pulsars and magnetars.Unprecedented DropOne way to examine whats going on with PSR 18460258 is to evaluate whats known as its braking index, a measure of how quickly the pulsars rotation slows down. For a rotation-powered pulsar, the braking index should be roughly constant. The pulsar then slows down according to a fixed power law, where the slower it rotates, the slower it slows down.In a recent study, Robert Archibald (McGill University) and collaborators report on 7 years worth of timing observations of PSR 18460258 after its odd magnetar-like outburst. They then compare these observations to 6.5 years of data from before the outburst. The team finds that the braking index for this bizarre

  5. Comparisonal Analysis of Manuevering and Braking

    Directory of Open Access Journals (Sweden)

    Artūras Žukas

    2011-04-01

    Full Text Available This article covers the possibility of avoiding a traffic accident considering a car driver who is fallen in a dangerous situation. In such a case, the driver can choose one of the following ways: hard braking or one of the types of maneuvering, including turning off, turning with straightening or changing a line regarding road surface type (dry asphalt, wet asphalt or snowy asphalt. The article also proposes formulas for calculating road distance the car travels till dead stop. Moreover, the tables display theoretical values taking into account various car speeds and road surfaces. The pictures help with determining the most suitable type of action in light of road and weather conditions as well as car speed. The pictures clearly show the dependence of road length on movement speed. At the end of the article, conclusions are proposed.Article in Lithuanian

  6. Chemonucleolysis of lumbar disc herniation

    International Nuclear Information System (INIS)

    Chemonucleolysis is an advantageous alternative to surgical treatment of lumbar disc herniation. To achieve the best results the indications must be strictly observed and the procedure itself must be technically perfect. In these circumstances a rapid, non-invasive and less expensive treatment of lumbar disc herniation is possible. (orig.)

  7. Electronic technique application in automotive industry and development trend%电子技术在汽车工业中的应用与发展趋势

    Institute of Scientific and Technical Information of China (English)

    贾泽宇

    2012-01-01

    Briefly introduce the application situation of modern electronic technique in automotive ABS system and drive anti-slip system,automotive dynamic control system and electronic brake distribution system, automotive electronic control suspension,automotive electronic control dynamic steering system,safety air bag, door lock emergency release system and GPS rescue system,expound the development trend of automotive electronic technique.%简要地介绍了现代电子技术在汽车制动防抱死系统与驱动防滑系统、汽车动态控制系统与电子制动力分配系统、汽车电控悬架、汽车电控动力转向系统、安全气囊、门锁紧急施放系统与GPS救援系统等方面的应用情况,阐述了汽车电子技术的发展趋势。

  8. Sensor Data Fusion in Automotive Applications

    OpenAIRE

    Lytrivis, Panagiotis; Thomaidis, George; Amditis, Angelos

    2009-01-01

    This chapter has summarized the state-of-the-art in sensor data fusion for automotive applications, showing that this is a relatively new discipline in the automotive research area, compared to signal processing, image processing or radar processing. Thus, there is a

  9. A comprehensive framework for automotive sustainability assessment

    OpenAIRE

    Jasinski, D.; Meredith, J.; Kirwan, K.

    2016-01-01

    Business efficiency, stakeholder pressure and the need for legislative compliance compel the automotive sector to design and manufacture fuel-efficient, low-impact, environmentally responsible and sustainable vehicles. Managing and responding to these multiple and sometimes conflicting interests requires the measurement of economic, environmental and societal performance. Although a number of automotive sustainability measures are mentioned within the literature, there is no singl...

  10. 77 FR 37471 - National Automotive Sampling System

    Science.gov (United States)

    2012-06-21

    ... complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you... National Highway Traffic Safety Administration National Automotive Sampling System AGENCY: National Highway... comments. SUMMARY: The NHTSA is conducting a comprehensive review of the National Automotive...

  11. Using Technology to Enhance an Automotive Program

    Science.gov (United States)

    Ashton, Denis

    2009-01-01

    Denis Ashton uses technology in his automotive technology program at East Valley Institute of Technology (EVIT) to positively impact student outcomes. Ashton, the department chair for the automotive programs at EVIT, in Mesa, Arizona, says that using an interactive PowerPoint curriculum makes learning fun for students and provides immediate…

  12. On disc-planet interactions in sub-keplerian discs

    CERN Document Server

    Paardekooper, S -J

    2009-01-01

    One class of protoplanetary disc models, the X-wind model, predicts strongly subkeplerian orbital gas velocities, a configuration which can be sustained by magnetic tension. We investigate disc-planet interactions in these subkeplerian discs, focusing on orbital migration for low-mass planets and gap formation for high-mass planets. We use linear calculations and non-linear hydrodynamical simulations to measure the torque and look at gap formation. In both cases, the subkeplerian nature of the disc is treated as a fixed external constraint. We show that, depending on the degree to which the disc is subkeplerian, the torque on low-mass planets varies between the usual Type I torque and the one-sided outer Lindblad torque, which is also negative but an order of magnitude larger. In strongly subkeplerian discs, corotation effects can be ignored, making migration fast and inward. Gap formation near the planet's orbit is more difficult in such discs, since there are no resonances close to the planet accommodating ...

  13. Advances in automotive control 2001

    Energy Technology Data Exchange (ETDEWEB)

    Kiencke, U.; Gissinger, G.L. (eds.)

    2001-07-01

    The aim of the 3rd IFAC Workshop 'Advances in Automotive Control', held in Karlsruhe, Germany on 28-30 March 2001, was to discuss the latest advances in relation to motor vehicles. The increase in road traffic in the 20th century was a major problem, and one of the challenges of the 21st century will be to improve driving safety and comfort. The proceedings covers: driveline control; driveline modelling; vehicle dynamics; electronic architecture; intelligent components; engine control; diagnostics; subsystems; engine modelling; and modelling of combustion and turbo-charging. 28 of the papers are abstracted here.

  14. Brake Pedal Displacement Measuring System based on Machine Vision

    Directory of Open Access Journals (Sweden)

    Chang Wang

    2013-10-01

    Full Text Available Displacement of brake pedal was an important characteristic of driving behavior. This paper proposed a displacement measure algorithm based on machine vision. Image of brake pedal was captured by camera from left side, and images were processed in industry computer. Firstly, average smooth algorithm and wavelet transform algorithm were used to smooth the original image consecutively. Then, edge extracting method which combined Roberts’s operator with wavelet analysis was used to identify the edge of brake pedal. At last, least square method was adopted to recognize the characteristic line of brake pedal’s displacement. The experimental results demonstrated that the proposed method takes the advantages of Roberts’s operator and wavelet transform, it can obtain better measurement result as well as linear displacement sensors

  15. 49 CFR 229.57 - Foundation brake gear.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.57... to the wheel to prevent localized thermal stress in the edge of the rim or the flange....

  16. Fishery Management Plan for Morgan Brake National Wildlife Refuge - 1992

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This management plan was prepared by the U. S. Fish and Wildlife Service for Morgan Brake National Wildlife Refuge. Data was provided by the Refuge and Area Office...

  17. Fishery Management Plan for Mathews Brake National Wildlife Refuge - 1985

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This management plan was prepared by the U.S. Fish and Wildlife Service for Mathew's Brake National Wildlife Refuge. Data was provided by the refuge and area office...

  18. Fishing Plan for Mathews Brake National Wildlife Refuge - 1981

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This proposal calls for the opening of Mathews Brake NWR to sport fishing. General regulations pertaining to licenses, creel limits, and methods of taking fish will...

  19. Deployable Engine Air-Brake for Drag Management Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ATA Engineering, Inc, proposes an SBIR program to demonstrate an innovative engine air-brake (EAB) technology that uses a deployable swirl vane mechanism to switch...

  20. Deployable Engine Air-Brake for Drag Management Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ATA Engineering, Inc., (ATA) proposes a Phase II SBIR program to demonstrate an innovative engine air-brake (EAB) technology that uses a deployable swirl vane...

  1. Handy Brake National Wildlife Refuge Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Handy Brake National Wildlife Refuge Habitat Management Plan provides a longterm vision and specific guidance on managing habitats for the resources of concern...

  2. Mathews Brake National Wildlife Refuge [Land Status Map

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Mathews Brake National Wildlife Refuge. It was generated from rectified aerial...

  3. Power Modulation Investigation for High Temperature (175-200 degrees Celcius) Automotive Application

    Energy Technology Data Exchange (ETDEWEB)

    McCluskey, F. P.

    2007-04-30

    Hybrid electric vehicles were re-introduced in the late 1990s after a century dominated by purely internal combustion powered engines[1]. Automotive players, such as GM, Ford, DaimlerChrysler, Honda, and Toyota, together with major energy producers, such as BPAmoco, were the major force in the development of hybrid electric vehicles. Most notable was the development by Toyota of its Prius, which was launched in Japan in 1997 and worldwide in 2001. The shift to hybrids was driven by the fact that the sheer volume of vehicles on the road had begun to tax the ability of the environment to withstand the pollution of the internal combustion engine and the ability of the fossil fuel industry to produce a sufficient amount of refined gasoline. In addition, the number of vehicles was anticipated to rise exponentially with the increasing affluence of China and India. Over the last fifteen years, major advances have been made in all the technologies essential to hybrid vehicle success, including batteries, motors, power control and conditioning electronics, regenerative braking, and power sources, including fuel cells. Current hybrid electric vehicles are gasoline internal combustion--electric motor hybrids. These hybrid electric vehicles range from micro-hybrids, where a stop/start system cuts the engine while the vehicle is stopped, and mild hybrids where the stop/start system is supplemented by regenerative braking and power assist, to full hybrids where the combustion motor is optimized for electric power production, and there is full electric drive and full regenerative braking. PSA Peugeot Citroen estimates the increased energy efficiency will range from 3-6% for the micro-hybrids to 15-25% for the full hybrids.[2] Gasoline-electric hybrids are preferred in US because they permit long distance travel with low emissions and high gasoline mileage, while still using the existing refueling infrastructure. One of the most critical areas in which technology has been

  4. Stability analysis and μ-synthesis control of brake systems

    OpenAIRE

    Lignon, Sylvain; Sinou, Jean-Jacques; Jezequel, Louis

    2006-01-01

    The concept of friction-induced brake vibrations, commonly known as judder, is investigated. Judder vibration is based on the class of geometrically induced or kinematic constraint instability. After presenting the modal coupling mechanism and the associated dynamic model, a stability analysis as well as a sensitivity analysis have been conducted in order to identify physical parameters for a brake design avoiding friction-induced judder instability. Next, in order to reduce the size of the i...

  5. Stability analysis and \\mu-synthesis control of brake systems

    OpenAIRE

    Lignon, Sylvain; Sinou, Jean-Jacques; Jezequel, Louis

    2008-01-01

    The concept of friction-induced brake vibrations, commonly known as judder, is investigated. Judder vibration is based on the class of geometrically induced or kinematic constraint instability. After presenting the modal coupling mechanism and the associated dynamic model, a stability analysis as well as a sensitivity analysis have been conducted in order to identify physical parameters for a brake design avoiding friction-induced judder instability. Next, in order to reduce the size of the i...

  6. 49 CFR 393.55 - Antilock brake systems.

    Science.gov (United States)

    2010-10-01

    ... Motor Vehicle Safety Standard (FMVSS) No. 105 (49 CFR 571.105, S5.5). (b) ABS malfunction indicators for... with an antilock brake system that meets the requirements of FMVSS No. 121 (49 CFR 571.121, S5.1.6.1(b... equipped with an antilock brake system that meets the requirements of FMVSS No. 121 (49 CFR 571.121,...

  7. AASPT Carbon/Carbon Aircraft Brake Disk Granted MPA

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Xi'an Chaoma Technology Co. Ltd. was issued Parts Manufacturer Approval (PMA) for Carbon/Carbon aircraft brake disk for Airbus 320 series by Civil Aviation Administration of China (CAAC). The company is held by Academy of Aerospace Solid Propulsion Technology (AASPT), a subsidiary of China Aerospace Science and Technology Corporation (CASC). It is the first approval given to a Chinese company to design and produce brakes for main civilian aircraft.

  8. OPTIMAL EMERGENCY VEHICLE BRAKING CONTROL BASED ON DYNAMIC FRICTION MODEL

    OpenAIRE

    Olmos, L.; L. Álvarez-Icaza

    2005-01-01

    A dynamic friction model for the tire-road interface is used in an optimal control scheme for emergency braking of vehicles. The controller sets a target relative velocity curve that the vehicle must track in order to achieve braking in minimum time. It is shown that this curve corresponds to the solution of a minimum time optimal control problem. The final goal of the control is to improve the safety levels in highway transportation.

  9. OPTIMAL EMERGENCY VEHICLE BRAKING CONTROL BASED ON DYNAMIC FRICTION MODEL

    Directory of Open Access Journals (Sweden)

    L. Olmos

    2005-04-01

    Full Text Available A dynamic friction model for the tire-road interface is used in an optimal control scheme for emergency braking ofvehicles. The controller sets a target relative velocity curve that the vehicle must track in order to achieve braking inminimum time. It is shown that this curve corresponds to the solution of a minimum time optimal control problem.The final goal of the control is to improve the safety levels in highway transportation.

  10. Discs in misaligned binary systems

    Science.gov (United States)

    Rawiraswattana, Krisada; Hubber, David A.; Goodwin, Simon P.

    2016-08-01

    We perform SPH simulations to study precession and changes in alignment between the circumprimary disc and the binary orbit in misaligned binary systems. We find that the precession process can be described by the rigid-disc approximation, where the disc is considered as a rigid body interacting with the binary companion only gravitationally. Precession also causes change in alignment between the rotational axis of the disc and the spin axis of the primary star. This type of alignment is of great important for explaining the origin of spin-orbit misaligned planetary systems. However, we find that the rigid-disc approximation fails to describe changes in alignment between the disc and the binary orbit. This is because the alignment process is a consequence of interactions that involve the fluidity of the disc, such as the tidal interaction and the encounter interaction. Furthermore, simulation results show that there are not only alignment processes, which bring the components towards alignment, but also anti-alignment processes, which tend to misalign the components. The alignment process dominates in systems with misalignment angle near 90°, while the anti-alignment process dominates in systems with the misalignment angle near 0° or 180°. This means that highly misaligned systems will become more aligned but slightly misaligned systems will become more misaligned.

  11. Automotive Battery Modelling and Management

    Directory of Open Access Journals (Sweden)

    N. M. Hammad

    2014-06-01

    Full Text Available The estimation of vehicle battery performance is typically addressed by testing the battery under specific operation conditions by using a model to represent the test results. Approaches for representing test results range from simple statistical models to neural networks to complex, physics-based models. Basing the model on test data could be problematical when testing becomes impractical with many years life time tests. So, real time estimation of battery performance, an important problem in automotive applications, falls into this area. In vehicles it is important to know the state of charge of the batteries in order to prevent vehicle stranding and to ensure that the full range of the vehicle operation is exploited. In this paper, several battery models have studied including analytical, electrical circuits, stochastic and electro- chemical models. Valve Regulated Lead Acid “VRLA” battery has been modelled using electric circuit technique. This model is considered in the proposed Battery Monitoring System “BMS”. The proposed BMS includes data acquisition, data analysis and prediction of battery performance under a hypothetical future loads. Based on these criteria, a microprocessor based BMS prototype had been built and tested in automotive Lab,. The tests show promising results that can be used in industrial applications

  12. Automotive stamped part fatigue design

    Directory of Open Access Journals (Sweden)

    Caudoux Mélanie

    2014-06-01

    Full Text Available Fatigue design of automotive axle parts is of prior concern because of these are high safety parts and they are expected to drive the overall vehicle mass reduction. In this framework, the stamping process is widely used to form axle parts, before assembling them by welding. Consequently, the mechanical and physical characteristics of the blank sheet are modified, having a strong influence on the fatigue behavior. In this paper, we address the consequences of the stamped process on the fatigue design and how they may be effectively taken into account in the automotive industry. Actually, the coupling between the stamping process and the fatigue design is under development at PSA Peugeot Citroën Company since several years. Such an analysis deals with some major topics: thickness variation, plastic hardening and deformation, and residual stress. All of these ingredients result in fatigue criteria evolutions: it is important to stress that the stamping process can have advantageous or disadvantageous consequences on the fatigue design. This is here highlighted on some examples, dealing with front and rear axles.

  13. Peripheral Disc Margin Shape and Internal Disc Derangement: Imaging Correlation in Significantly Painful Discs Identified at Provocation Lumbar Discography

    OpenAIRE

    Bartynski, W.S.; Rothfus, W.E.

    2012-01-01

    Annular margin shape is used to characterize lumbar disc abnormality on CT/MR imaging studies. Abnormal discs also have internal derangement including annular degeneration and radial defects. The purpose of this study was to evaluate potential correlation between disc-margin shape and annular internal derangement on post-discogram CT in significantly painful discs encountered at provocation lumbar discography (PLD).

  14. Development of automobile brake lining using pulverized cow hooves

    Directory of Open Access Journals (Sweden)

    Katsina C. BALA

    2016-06-01

    Full Text Available Asbestos has been used for so long as automobile brake lining material because of its good physical and chemical properties. However, due to the health hazard associated with its handling, it has lost favour and several alternative materials are being increasingly used. Asbestos-free brake lining was developed in this work using pulverized cow hooves along with epoxy resin, barium sulphate, graphite and aluminium oxide. This was with a view to exploiting the characteristics of cow hooves, which are largely discarded as waste materials to replace asbestos which has been found to be carcinogenic. Samples of brake linings were produced using compressive moulding in which the physical and mechanical properties of the samples were studied. The results obtained showed that proper bonding was achieved as the percentage by weight of epoxy resin increased and percentage by weight of pulverized cow hooves decreased. The hardness, compressive strength, coefficient of friction, water and oil absorption, relative density and wear rate of the brake linings were determined and compared with existing brake lining properties. The result indicates that pulverized cow hooves can be used as brake lining material for automobiles.

  15. Are galaxy discs optically thick?

    International Nuclear Information System (INIS)

    We re-examine the classical optical evidence for the low optical depths traditionally assigned to spiral discs and argue that it is highly model-dependent and unconvincing. In particular, layered models with a physically thin but optically thick dust layer behave like optically thin discs. The opposite hypotheses, that such discs are optically thick is then examined in the light of modern evidence. We find it to be consistent with the near-infrared and IRAS observations, with the surface brightnesses, with the HI and CO column densities and with the Hα measurements. (author)

  16. High Level Lomber Disc Hernias

    OpenAIRE

    Ateş, Özkan; Tarım, Özcan; Koçak, Ayhan; Önal, S. Çağatay; Çaylı, Süleyman R.; Şahinbeyoğlu, Baran; Tektaş, Şevket

    2002-01-01

    Aim: The scope of this study is to investigate the correlation between the clinical and radiological findings of high level lomber disc hernia (L1-2, L2-3, L3-4) and surgical outcome. Material and Method: 23 high level lomber disc hernia out of 262 lomber disc cases operated between January1996 and November 2001 at the department of Neurosurgery , Faculty of Medicine, İnönü Üniversity (Malatya Turkey) were retrospectively reviewed. Results: 39.1% of the cases were male and...

  17. Total Disc Arthroplasty for Treating Lumbar Degenerative Disc Disease

    OpenAIRE

    Mostofi, Keyvan

    2015-01-01

    Study Design Lumber disc arthroplasty is a technological advancement that has occurred in the last decade to treat lumbar degenerative disk diseases. Purpose The aim of this retrospective study was to establish the impact and outcomes of managing patients with lumbar degenerative disk disease who have been treated with lumbar total disc arthroplasty (TDA). Overview of Literature Several studies have shown promising results following this surgery. Methods We reviewed the files of 104 patients ...

  18. Predict optimize the friction characteristics of brake pads; Brake pad no masatsu tokusei no yosoku to saitekika

    Energy Technology Data Exchange (ETDEWEB)

    Saotome, H. [Nissin Kogyo Co., Tokyo (Japan); Kato, T. [The University of Tokyo, Tokyo (Japan)

    1997-10-01

    The effect of the friction and the wear properties of brake pads were experimentally studied using a test rig of scale of 1/10 of the system used in a commercial car. The experimental data were investigated by the Multiple Regression Analysis and the Neural Network, and the effects of volume % of components on the friction and the wear properties were predicted. In addition the components of brake pads are optimized by Genetic Algorithms. 8 refs., 9 figs., 4 tabs.

  19. Thermal measurement of brake pad lining surfaces during the braking process

    Science.gov (United States)

    Piątkowski, Tadeusz; Polakowski, Henryk; Kastek, Mariusz; Baranowski, Pawel; Damaziak, Krzysztof; Małachowski, Jerzy; Mazurkiewicz, Łukasz

    2012-06-01

    This paper presents the test campaign concept and definition and the analysis of the recorded measurements. One of the most important systems in cars and trucks are brakes. The braking temperature on a lining surface can rise above 500°C. This shows how linings requirements are so strict and, what is more, continuously rising. Besides experimental tests, very supportive method for investigating processes which occur on the brake pad linings are numerical analyses. Experimental tests were conducted on the test machine called IL-68. The main component of IL-68 is so called frictional unit, which consists of: rotational head, which convey a shaft torque and where counter samples are placed and translational head, where samples of coatings are placed and pressed against counter samples. Due to the high rotational speeds and thus the rapid changes in temperature field, the infrared camera was used for testing. The paper presents results of analysis registered thermograms during the tests with different conditions. Furthermore, based on this testing machine, the numerical model was developed. In order to avoid resource demanding analyses only the frictional unit (described above) was taken into consideration. Firstly the geometrical model was performed thanks to CAD techniques, which in the next stage was a base for developing the finite element model. Material properties and boundary conditions exactly correspond to experimental tests. Computations were performed using a dynamic LS-Dyna code where heat generation was estimated assuming full (100%) conversion of mechanical work done by friction forces. Paper presents the results of dynamic thermomechanical analysis too and these results were compared with laboratory tests.

  20. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... so much different than the fusion. The ProDisc C total disc replacement from Synthes Spine is an ... intervertebral disc in the cervical spine. The ProDisc C is indicated for patients suffering from intractable symptomatic ...

  1. Debris disc formation induced by planetary growth

    CERN Document Server

    Kobayashi, Hiroshi

    2014-01-01

    Several hundred stars older than 10 million years have been observed to have infrared excesses. These observations are explained by dust grains formed by the collisional fragmentation of hidden planetesimals. Such dusty planetesimal discs are known as debris discs. In a dynamically cold planetesimal disc, collisional coagulation of planetesimals produces planetary embryos which then stir the surrounding leftover planetesimals. Thus, the collisional fragmentation of planetesimals that results from planet formation forms a debris disc. We aim to determine the properties of the underlying planetesimals in debris discs by numerically modelling the coagulation and fragmentation of planetesimal populations. The brightness and temporal evolution of debris discs depend on the radial distribution of planetesimal discs, the location of their inner and outer edges, their total mass, and the size of planetesimals in the disc. We find that a radially narrow planetesimal disc is most likely to result in a debris disc that ...

  2. Vortex migration in protoplanetary discs

    Directory of Open Access Journals (Sweden)

    Papaloizou John C. B.

    2013-04-01

    Full Text Available Vortices embedded in protoplanetary discs can act as obstacles to the unperturbed disc flow. The resulting velocity perturbations propagate away from the vortex in the form of density waves that transport angular momentum. Any asymmetry between the inner and the outer density wave means that the region around the vortex has to change its angular momentum. We find that this leads to orbital migration of the vortex. Asymmetric waves always arise except in the case of a disc with constant pressure, for isothermal as well as non-isothermal discs. Depending on the size and strength of the vortex, the resulting migration time scales can be as short as a few thousand orbits.

  3. Intelligently Controllable Walker with Magnetorheological Fluid Brake

    Science.gov (United States)

    Kikuchi, Takehito; Tanida, Sosuke; Tanaka, Toshimasa; Kobayashi, Keigo; Mitobe, Kazuhisa

    Caster walkers are supporting frames with casters and wheels. These tools are regularly utilized as life support tools or walking rehabilitation tools in hospitals, nursing homes and individual residences. Users of the walkers can easily move it thanks to its wheels and casters. However falling accidents often happen when it moves without users. The falling accident is very serious problem and one of leading causes of secondary injuries. In the other case, it is hard to move to desired directions if users have imbalance in their motor functions or sensory functions, e.g., hemiplegic patients. To improve safeness and operability of the walkers, we installed compact MR fluid brakes on the wheels and controlled walking speed and direction of the walker. We named this intelligently controllable walker, “i-Walker” and discussed on the control methods and experimental results in this paper. Preliminary trials for direction control of the first-generation of the i-Walker (i-Walker1) are presented. On the basis of the results, we improved the control method and hardware of the i-Walker1, and developed the second-generation (i-Walker2). System description and experimental results of the i-Walker2 are also described. The i-Walker2 has better operability and lower energy consumption than that of the i-Walker1. The line-tracing controller of the i-Walker2 well controls human motions during walking experiments on the target straight line.

  4. Green innovation adoption in automotive supply chain

    DEFF Research Database (Denmark)

    Zailani, Suhaiza; Govindan, Kannan; Iranmanesh, Mohammad;

    2015-01-01

    Green innovation has currently been receiving a great deal of international attention because of the growing concern of consumers, governments, and the community as a whole with regard to the degradation of natural resources and environmental pollution. The automotive sector is one of the leading...... generators of industrial waste that affect the quality of the natural environment. This study aims to investigate the determinants of green innovation adoption and its effect on firm performance. Data were gathered by surveying 153 firms in the Malaysian automotive supply chain industry. Data were analyzed......). These results have important implications for designing strategic plans for the Malaysian automotive industry....

  5. Cervical Disc Disease: Biomechanical Aspects

    OpenAIRE

    Kolstad, Frode

    2011-01-01

    Degenerative disc disease in the cervical spine may cause significant pain and disability. Patients present themselves with neck pain, radiculopathy, and/or myelopathy. When the symptoms do not improve with conservative treatment, surgical treatment is considered. The goal of surgical treatment is to decompress nervous structures and to restore the normal anatomical conditions of disc height, alignment, and stability.The present thesis concerns four studies involving the treatment of cervical...

  6. Corticosteroids in Lumbar Disc Surgery

    OpenAIRE

    Lundin, Anders

    2005-01-01

    In a prospective randomised double-blind study eighty patients with MRI verified lumbar disc herniation and corresponding clinical findings underwent microscopic disc removal. The patients were peroperatively given systemic and local corticosteroids or placebo, and followed for 2 years. The hospital stay and time to return to full-time work was significantly shorter in the treatment group. Pain measured as worst pain during the last week was also lower in the corticosteroid group. The results...

  7. Lumbar disc cyst with contralateral radiculopathy

    OpenAIRE

    Kishore Tourani; Belman Murali; Akshay Sahoo; Dandu Ravi Varma; Narayan Prasad

    2012-01-01

    Disc cysts are uncommon intraspinal cystic lesions located in the ventrolateral epidural space. They communicate with the nucleus pulposus of the intervertebral disc and cause symptoms by radicular compression. We report a unique case of lumbar disc cyst that was associated with disc herniation and contralateral radiculopathy. A 22 year old male presented with one month history of back-ache radiating to the left leg. Magnetic Resonance Imaging (MRI) showed L3-L4 disc herniation with annular t...

  8. Technology Transfer in the Global Automotive Value Chain. Lessons from the Turkish Automotive Industry

    OpenAIRE

    M. Teoman Pamukçu; Alper Sönmez

    2011-01-01

    The automotive industry is one of the main contributors to value added, employment and exports of the Turkish economy and it has undergone major changes since the mid-nineties. Most of the automotive manufacturers in Turkey are either joint ventures or wholly-owned affiliates of multinational companies. Literature on global value chains point to the possibility of technology transfer occurring through backward linkages from automotive manufacturers to their suppliers. We test for the existenc...

  9. Does Automotive Service Excellence (ASE) Certification Enhance Job Performance of Automotive Service Technicians?

    OpenAIRE

    Kolo, Emmanuel

    2006-01-01

    The purpose of this study was to determine if Automotive Service Excellence (ASE) certification of automotive service technicians in independent dealerships enhanced job performance. Descriptive survey methodology was used to gather information for 100 automotive technicians (50 ASE-certified and 50 non-certified technicians) located in 50 different work sites. Each siteâ s service manager was asked to complete a questionnaire and a rating scale for two technicians, one ASE certified and on...

  10. Counter-Rotating Accretion Discs

    CERN Document Server

    Dyda, Sergei; Ustyugova, Galina V; Romanova, Marina M; Koldoba, Alexander V

    2014-01-01

    Counter-rotating discs can arise from the accretion of a counter-rotating gas cloud onto the surface of an existing co-rotating disc or from the counter-rotating gas moving radially inward to the outer edge of an existing disc. At the interface, the two components mix to produce gas or plasma with zero net angular momentum which tends to free-fall towards the disc center. We discuss high-resolution axisymmetric hydrodynamic simulations of a viscous counter-rotating disc for cases where the two components are vertically separated and radially separated. The viscosity is described by an isotropic $\\alpha-$viscosity including all terms in the viscous stress tensor. For the vertically separated components a shear layer forms between them. The middle of this layer free-falls to the disk center. The accretion rates are increased by factors $\\sim 10^2-10^4$ over that of a conventional disc rotating in one direction with the same viscosity. The vertical width of the shear layer and the accretion rate are strongly dep...

  11. Parametric studies on automotive radiators

    International Nuclear Information System (INIS)

    This paper presents a set of parametric studies performed on automotive radiators by means of a detailed rating and design heat exchanger model developed by the authors. This numerical tool has been previously verified and validated using a wide experimental data bank. A first part of the analysis focuses on the influence of working conditions on both fluids (mass flows, inlet temperatures) and the impact of the selected coolant fluid. Following these studies, the influence of some geometrical parameters is analysed (fin pitch, louver angle) as well as the importance of coolant flow lay-out on the radiator global performance. This work provides an overall behaviour report of automobile radiators working at usual range of operating conditions, while significant knowledge-based design conclusions have also been reported. The results show the utility of this numerical model as a rating and design tool for heat exchangers manufacturers, being a reasonable compromise between classic ε - NTU methods and CFD

  12. Study of Stress Sources and Critical Stress Combinations for the Input Shaft of a Longitudinally Mounted Four Speed Automotive Automatic Transmission Model

    OpenAIRE

    N A Abdel-halim

    2013-01-01

    In the present paper; two models of the input shaft for a Longitudinal Mounted four Speed Automotive Automatic Transmission for the first time were introduced to describe the input shaft critical loads. In the first model; the DC (Direct Clutch) connects two gears together. This gives no change in the set torque (the set output torque equal to the set input torque). In the second model; the ODB (Over Drive Brake) fixes one element of the planetary set. This is resulting, the gear set gives r...

  13. Energy system feasibility study of an Otto cycle/Stirling cycle hybrid automotive engine

    Energy Technology Data Exchange (ETDEWEB)

    Cullen, Barry; McGovern, Jim [Department of Mechanical Engineering, Dublin Institute of Technology, Dublin (Ireland)

    2010-02-15

    The aim of this study was to investigate the feasibility of utilising a Stirling cycle engine as an exhaust gas waste heat recovery device for an Otto cycle internal combustion engine (ICE) in the context of an automotive power plant. The hybrid arrangement would produce increased brake power output for a given fuel consumption rate when compared to an ICE alone. The study was dealt with from an energy system perspective with design practicalities such as power train integration, location of auxiliaries, manufacture costs and other general plant design considerations neglected. The study necessitated work in two distinct areas: experimental assessment of the performance characteristics of an existing automotive Otto cycle ICE and mathematical modelling of the Stirling cycle engine based on the output parameters of the ICE. It was subsequently found to be feasible in principle to generate approximately further 30% useful power in addition to that created by the ICE by using a Stirling cycle engine to capture waste heat expelled from the ICE exhaust gases over the complete range of engine operating speeds. (author)

  14. Study of LED modulation effect on the photometric quantities and beam homogeneity of automotive lighting

    Science.gov (United States)

    Koudelka, Petr; Hanulak, Patrik; Jaros, Jakub; Papes, Martin; Latal, Jan; Siska, Petr; Vasinek, Vladimir

    2015-07-01

    This paper discusses the implementation of a light emitting diode based visible light communication system for optical vehicle-to-vehicle (V2V) communications in road safety applications. The widespread use of LEDs as light sources has reached into automotive fields. For example, LEDs are used for taillights, daytime running lights, brake lights, headlights, and traffic signals. Future in the optical vehicle-to-vehicle (V2V) communications will be based on an optical wireless communication technology that using LED transmitter and a camera receiver (OCI; optical communication image sensor). Utilization of optical V2V communication systems in automotive industry naturally brings a lot of problems. Among them belongs necessity of circuit implementation into the current concepts of electronic LED lights control that allows LED modulation. These circuits are quite complicated especially in case of luxury cars. Other problem is correct design of modulation circuits so that final vehicle lightning using optical vehicle-to-vehicle (V2V) communication meets standard requirements on Photometric Quantities and Beam Homogeneity. Authors of this article performed research on optical vehicle-to-vehicle (V2V) communication possibilities of headlight (Jaguar) and taillight (Skoda) in terms of modulation circuits (M-PSK, M-QAM) implementation into the lamp concepts and final fulfilment of mandatory standards on Photometric Quantities and Beam Homogeneity.

  15. Nonlinear estimation and control of automotive drivetrains

    CERN Document Server

    Chen, Hong

    2014-01-01

    Nonlinear Estimation and Control of Automotive Drivetrains discusses the control problems involved in automotive drivetrains, particularly in hydraulic Automatic Transmission (AT), Dual Clutch Transmission (DCT) and Automated Manual Transmission (AMT). Challenging estimation and control problems, such as driveline torque estimation and gear shift control, are addressed by applying the latest nonlinear control theories, including constructive nonlinear control (Backstepping, Input-to-State Stable) and Model Predictive Control (MPC). The estimation and control performance is improved while the calibration effort is reduced significantly. The book presents many detailed examples of design processes and thus enables the readers to understand how to successfully combine purely theoretical methodologies with actual applications in vehicles. The book is intended for researchers, PhD students, control engineers and automotive engineers. Hong Chen is a professor at the State Key Laboratory of Automotive Simulation and...

  16. Fatal exit the automotive black box debate

    CERN Document Server

    Kowalick, Tom

    2005-01-01

    "Fatal Exit: The Automotive Black Box Debate cuts through thirty years of political wrangling and institutional biases to provide an argument for the Motor Vehicle Event Data Recorder (MVEDR). This automotive equivalent of an airplane's flight recorder or black box is intended to solve the mysteries of car crashes and improve the safety of our roads. The reader is taken inside the automotive industry and the government highway safety establishment to foster an understanding of the politics and the positions on all sides of this safety debate. The author takes an unbiased approach, chronologically presenting each argument and uncovering the agendas and mandates of each of the stakeholders." "This publication is essential reading for all consumers who need to have their voices heard on this critical issue, as well as for attorneys, public safety advocates, public policy administrators, engineers, automotive professionals, journalists, and insurance executives."--Jacket.

  17. Sustainable automotive energy system in China

    CERN Document Server

    CAERC, Tsinghua University

    2014-01-01

    This book identifies and addresses key issues of automotive energy in China. It covers demography, economics, technology and policy, providing a broad perspective to aid in the planning of sustainable road transport in China.

  18. Minimizing cryopreservation-induced loss of disc cell activity for storage of whole intervertebral discs

    OpenAIRE

    SCW Chan; SKL Lam; VYL Leung; Chan, D.; KDK Luk; KMC Cheung

    2010-01-01

    Severe intervertebral disc (IVD) degeneration often requires disc excision and spinal fusion, which leads to loss of spinal segment mobility. Implantation of an allograft disc or tissue engineered disc construct emerges as an alternative to artificial disc replacement for preserving the motion of the degenerated level. Establishment of a bank of cadaveric or engineered cryopreserved discs enables size matching, and facilitates clinical management. However, there is a lack of understanding of ...

  19. Prosthetic leg powered by MR brake and SMA wires

    Science.gov (United States)

    Nguyen, The; Munguia, Vicente; Calderon, Jose

    2014-04-01

    Current knee designs for prosthetic legs rely on electric motors for both moving and stationary states. The electric motors draw an especially high level of current to sustain a fixed position. The advantage of using magnetorheological (MR) fluid is that it requires less current and can have a variable braking torque. Besides, the proposed prosthetic leg is actuated by NiTinol wire, a popular shape memory alloy (SMA). The incorporation of NiTinol gives the leg more realistic weight distribution with appropriate arrangement of the batteries and wires. The prosthesis in this research was designed with MR brake as stopping component and SMA wire network as actuating component at the knee. The MR brake was designed with novel non-circular shape for the rotor that improved the braking torque while minimizing the power consumption. The design also helped simplify the control of braking process. The SMA wire network was design so that the knee motion was actively rotated in both directions. The SMA wires were arranged and played very similar role as the leg's muscles. The study started with the overall solid design of the knee including both MR and SMA parts. Theoretical models were derived and programmed in Simulink for both components. The simulation was capable of predicting the power required for moving the leg or hold it in a fixed position for a certain amount of time. Subsequently, the design was prototyped and tested to validate the theoretical prediction. The theoretical models were updated accordingly to correlate with the experimental data.

  20. Sound field control in the automotive environment

    OpenAIRE

    Cheer, Jordan; Elliott, Stephen; Jung, Woomin

    2015-01-01

    Active control of engine and road noise in the automotive environment has been investigated within the automotive industry for around 20 years. This interest is due to both the potential to reduce vehicle noise, and the ability to remove passive noise control treatments and, therefore, improve fuel efficiency. The most successful commercial systems have generally used the loudspeakers of the car audio system to globally control engine or road noise at low frequencies. It is also possible to u...

  1. Super High Strength Steel for automotive applications

    OpenAIRE

    CONFENTE, Mario; SCHNEIDER, Emmanuel; BOMONT, Olivier; LESCALIER, Christophe; BOMONT-ARZUR, Anne

    2008-01-01

    Intensive weight savings and out-sizing programs are developed in automotive industry and lead to increase the mechanical properties of the material of the automotive parts. ArcelorMittal has developed specific steel grades known as Super High Strength Steels which are designed for both high ductility and toughness and fatigue resistance. This paper investigates machinability for a drilling operation using an experimental methodology. One of the materials is a new low bainitic steel grade. Ex...

  2. Virtual Tryout Technologies for Preparing Automotive Manufacturing

    OpenAIRE

    Takahashi, Susumu

    2012-01-01

    It is important to reduce the weight of the automotive and to shorten the development period for reduction of CO2 discharge. For these purpose, virtual tryout technologies have been introduced automotive industry. Every process from stamping to assembly for car development has introduced CAD design and numerical simulation such as forming simulation, dimensional accuracy simulation such as forming simulation, dimensional accuracy simulation and so on. In this paper, sheet metal forming simula...

  3. Automotive perspective on laser material processing

    International Nuclear Information System (INIS)

    In this paper a broad review is given of the development and use of laser processing in the automotive industry. a brief introduction to the major types of processing lasers and related systems is followed by a summary of the major processing regimes. Examples are given of the automotive industry's use of lasers in a variety of applications, from heat treating and welding, to cutting and marking

  4. Multidisciplinary Design Optimization of Automotive Structures

    OpenAIRE

    Domeij Bäckryd, Rebecka

    2013-01-01

    Multidisciplinary design optimization (MDO) can be used as an effective tool to improve the design of automotive structures. Large-scale MDO problems typically involve several groups who must work concurrently and autonomously for reasons of efficiency. When performing MDO, a large number of designs need to be rated. Detailed simulation models used to assess automotive design proposals are often computationally expensive to evaluate. A useful MDO process must distribute work to the groups inv...

  5. INFLUENCE OF AUTOMOTIVE CLUSTERS IN REGIONAL DEVELOPMENT

    OpenAIRE

    Constantin BORDEI

    2014-01-01

    This paper proposes an overview of the evolution in the automotive sector in the process of regional development. The fundamental changes made by the component supplier sector improved the regional development and manufacturing process. Automotive industry is one of the modern sectors in many countries that benefits of a high technology impact and creates jobs that reduces unemployment across Europe. The auto industry changed cities, regions and countries into poles of development and it beco...

  6. Architecting and Modeling Automotive Embedded Systems

    OpenAIRE

    Larses, Ola

    2005-01-01

    Dealing properly with electronics and software will be a strong competitive advantage in the automotive sector in the near future. Electronics are driving current innovations and are at the same time becoming a larger part of the cost of the vehicle. In order to be successful as an automotive manufacturer, innovations must be introduced in the vehicle without compromising the final price tag. Also, the electronics has to compete with, and win over, the dependability of well known and proven m...

  7. Operationalising luxury in the premium automotive industry

    OpenAIRE

    Bridle, Bernadette

    2010-01-01

    This thesis presents an Action Research project investigating the use of customers’ perceptions of premium and luxury cars within the premium automotive industry. The research was sponsored by Jaguar Land Rover (JLR), a UK-based automotive manufacturer. An inductive, phenomenological approach was adopted in which JLR’s Premiumness Research Programme (PRP) was used as a case study to build an understanding of the consumer’s perception of luxury, to discover how to communic...

  8. Comparative Advantage in the Asian Automotive Industry

    OpenAIRE

    Somsupa Nopprach

    2010-01-01

    This paper seeks to analyze determinants of Asian countries' comparative advantage in the automotive industry. The effects of supporting industries, factor availability, factor intensity, transportation costs, and of the scale of foreign investment in the industry on the level of countries' comparative advantage are on focus. The results highlight the importance of strong supporting industries in raising a country's comparative advantage in the automotive industry. Furthermore, it is found th...

  9. Automotive fuels from biomass via gasification

    International Nuclear Information System (INIS)

    There exists already a market of bio-automotive fuels i.e. bioethanol and biodiesel produced from food crops in many countries. From the viewpoint of economics, environment, land use, water use and chemical fertilizer use, however, there is a strong preference for the use of woody biomass and various forest/agricultural residues as the feedstock. Thus, the production of 2nd generation of bio-automotive fuels i.e. synthetic fuels such as methanol, ethanol, DME, FT-diesel, SNG and hydrogen through biomass gasification seems promising. The technology of producing synthetic fuels is well established based on fossil fuels. For biomass, however, it is fairly new and the technology is under development. Starting from the present market of the 1st generation bio-automotive fuels, this paper is trying to review the technology development of the 2nd generation bio-automotive fuels from syngas platform. The production of syngas is emphasized which suggests appropriate gasifier design for a high quality syngas production. A number of bio-automotive fuel demonstration plant will be presented, which gives the state of the art in the development of BTS (biomass to synthetic fuels) technologies. It can be concluded that the 2nd generation bio-automotive fuels are on the way to a breakthrough in the transport markets of industrial countries especially for those countries with a strong forest industry. (author)

  10. Effect of optic disc size or age on evaluation of optic disc variables

    OpenAIRE

    Kee, C.; Koo, H.; Ji, Y; S. Kim

    1997-01-01

    AIMS/BACKGROUND—It has been reported that the number of optic nerve fibres decrease with age, and the cup/disc (C/D) ratio increases as the optic disc size increases. Consequently, the normal value of the optic disc variables measured by an optic disc analyser may change according to the optic disc size or age. The effect of individual variations in optic disc size or age on interpretation of optic disc variables was investigated.
METHODS—Topographic optic disc variables of 104 normal Asian a...

  11. Optimal design of a magneto-rheological brake absorber for torsional vibration control

    International Nuclear Information System (INIS)

    This research presents an optimal design of a magneto-rheological (MR) brake absorber for torsional vibration control of a rotating shaft. Firstly, the configuration of an MR brake absorber for torsional vibration control of a rotating shaft system is proposed. Then, the braking torque of the MR brake is derived based on the Bingham plastic model of the MR fluid. By assuming that the behaviour of the MR brake absorber is similar to that of a dry friction torsional damper, the optimal braking torque to control the torsional vibration is determined and validated by simulation. The optimal design problem of the MR brake absorber is then developed and a procedure to solve the optimal problem is proposed. Based on the proposed optimal design procedure, the optimal design of a specific rotating shaft system is performed. Vibration control performance of the shaft system employing the optimized MR brake absorber is then investigated through simulation and discussion on the results is given. (paper)

  12. Freshwater Fish Survey of Mathews Brake Water Body - 1980 and 1981

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A Freshwater Fish Survey of Mathews Brake water body including land not within Mathews Brake NWR. Methods included Electroshocker, creel census, and seine.

  13. 49 CFR 571.116 - Standard No. 116; Motor vehicle brake fluids.

    Science.gov (United States)

    2010-10-01

    ... WHEN ADDING BRAKE FLUID. (2) KEEP BRAKE FLUID CLEAN AND DRY. Contamination with dirt, water, petroleum... paraffin. Do not use a standard with an age exceeding three months. (1) Potassium hydrogen phthalate...

  14. Surrogate models for efficient stability analysis of brake systems

    Science.gov (United States)

    Nechak, Lyes; Gillot, Frédéric; Besset, Sébastien; Sinou, Jean-Jacques

    2015-07-01

    This study assesses capacities of the global sensitivity analysis combined together with the kriging formalism to be useful in the robust stability analysis of brake systems, which is too costly when performed with the classical complex eigenvalues analysis (CEA) based on finite element models (FEMs). By considering a simplified brake system, the global sensitivity analysis is first shown very helpful for understanding the effects of design parameters on the brake system's stability. This is allowed by the so-called Sobol indices which discriminate design parameters with respect to their influence on the stability. Consequently, only uncertainty of influent parameters is taken into account in the following step, namely, the surrogate modelling based on kriging. The latter is then demonstrated to be an interesting alternative to FEMs since it allowed, with a lower cost, an accurate estimation of the system's proportions of instability corresponding to the influent parameters.

  15. Stability Control of Vehicle Emergency Braking with Tire Blowout

    Directory of Open Access Journals (Sweden)

    Qingzhang Chen

    2014-01-01

    Full Text Available For the stability control and slowing down the vehicle to a safe speed after tire failure, an emergency automatic braking system with independent intellectual property is developed. After the system has received a signal of tire blowout, the automatic braking mode of the vehicle is determined according to the position of the failure tire and the motion state of vehicle, and a control strategy for resisting tire blowout additional yaw torque and deceleration is designed to slow down vehicle to a safe speed in an expected trajectory. The simulating test system is also designed, and the testing results show that the vehicle can be quickly stabilized and kept in the original track after tire blowout with the emergency braking system described in the paper.

  16. Dynamics Models of Interacting Torques of Hydrodynamic Retarder Braking Process

    Directory of Open Access Journals (Sweden)

    Wenhao Shen

    2013-01-01

    Full Text Available Hydrodynamic retarder is a kind of assist braking device, which can transfer the vehicle kinetic energy into the heat energy of working medium. There are complicated three-dimensional viscous incompressible turbulent flows in hydrodynamic retarder, so that it is difficult to represent the parameters changing phenomenon and investigate the interactional law. In order to develop a kind of reliable theoretical model for internal flow field, in this study, the dynamics models of interacting torques between impellers and working fluid were constructed based on braking energy transfer principle by using Euler theory to describe the flow state in view of time scale. The model can truly represent the dynamic braking process.

  17. Braking Performance of a Biomimetic Squid-Like Underwater Robot

    Institute of Scientific and Technical Information of China (English)

    Md.Mahbubar Rahman; Sinpei Sugimori; Hiroshi Miki; Risa Yamamoto; Yugo Sanada; Yasuyuki Toda

    2013-01-01

    In this study,the braking performance of the undulating fin propulsion system ofa biomimetic squid-like underwater robot was investigated through free run experiment and simulation of the quasi-steady mathematical model.The quasi-steady equations of motion were solved using the measured and calculated hydrodynamic forces and compared with free-run test results.Various braking strategies were tested and discussed in terms of stopping ability and the forces acting on the stopping stage.The stopping performance of the undulating fin propulsion system tured out to be excellent considering the short stopping time and short stopping distance.This is because of the large negative thrust produced by progressive wave in opposite direction.It was confirmed that the undulating fin propulsion system can effectively perform braking even in complex underwater explorations.

  18. What can the braking indices tell us about pulsars' nature?

    CERN Document Server

    Yue, Y L; Zhu, W W

    2006-01-01

    As a result of observational difficulties, braking indices of only six rotation-powered pulsars are obtained with certainty, all of which are remarkably smaller than the value ($n=3$) expected for pure magnetodipole radiation model. This is still a real fundamental question not being well answered after nearly forty years of the discovery of pulsar. The main problem is that we are shamefully not sure about the dominant mechanisms that result in pulsars' spin-down. Based on the previous works, the braking index is re-examined, with a conclusion of suggesting a constant gap potential drop for pulsars with magnetospheric activities. New constrains on model parameters from observed braking indices are presented.

  19. Chondrule transport in protoplanetary discs

    Science.gov (United States)

    Goldberg, Aaron Z.; Owen, James E.; Jacquet, Emmanuel

    2015-10-01

    Chondrule formation remains one of the most elusive early Solar system events. Here, we take the novel approach of employing numerical simulations to investigate chondrule origin beyond purely cosmochemical methods. We model the transport of generically produced chondrules and dust in a 1D viscous protoplanetary disc model in order to constrain the chondrule formation events. For a single formation event we are able to match analytical predictions of the memory they retain of each other (complementarity), finding that a large mass accretion rate (≳10-7 M⊙ yr-1) allows for delays on the order of the disc's viscous time-scale between chondrule formation and chondrite accretion. Further, we find older discs to be severely diminished of chondrules, with accretion rates ≲10-9 M⊙ yr-1 for nominal parameters. We then characterize the distribution of chondrule origins in both space and time, as functions of disc parameters and chondrule formation rates, in runs with continuous chondrule formation and both static and evolving discs. Our data suggest that these can account for the observed diversity between distinct chondrite classes, if some diversity in accretion time is allowed for.

  20. Simplified model of eddy current brakes and its use for optimization

    OpenAIRE

    Holtmann, Christoph/C.H.; Rinderknecht, Frank/F.R.; Friedrich, Horst E./H.E.F.

    2015-01-01

    The electrification of vehicles makes it possible to think about new concepts to substitute conventional technologies. For example in an electrical drive train, with a traction motor for each wheel mechanical friction brakes can be replaced by eddy current brakes. In this work a method for optimizing the torque density of eddy current brakes is presented. For a fast optimization process the model of the eddy current brake is split up in two levels of detail. In the first level a global model ...

  1. Investigation of Friction Behaviors of Brake Shoe Materials using Metallic Filler

    OpenAIRE

    E. Surojo; Jamasri; V. Malau; M.N. Ilman

    2015-01-01

    Some vehicles use brake shoe made from semi-metallic materials. Semi-metallic brake shoes are made from a combination of metallic and non-metallic materials. Metallic particles are added in the formulation of brake shoe material to improve composites characteristics. In this paper, friction behaviors of brake shoe material using metallic filler were investigated. Machining chips of cast iron and copper wire of electric motor used were incorporated in composite as metallic fillers with amount ...

  2. Tidally-induced warps in protostellar discs

    OpenAIRE

    Terquem, C.; Papaloizou, J.; Nelson, R.(University of California, Davis, Davis, USA)

    1998-01-01

    We review results on the dynamics of warped gaseous discs. We consider tidal perturbation of a Keplerian disc by a companion star orbiting in a plane inclined to the disc. The perturbation induces the precession of the disc, and thus of any jet it could drive. In some conditions the precession rate is uniform, and as a result the disc settles into a warp mode. The tidal torque also leads to the truncation of the disc, to the evolution of the inclination angle (not necessarily towards alignmen...

  3. Automotive Electrical and Electronic System II; Automotive Mechanics-Intermediate: 9045.04.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    This automotive electrical and electronic system course is an intermediate course designed for the student who has completed automotive Electrical and Electronic System I. The theory and principles of operation of the components of the starting and charging systems and other electrical accessory systems in the automobile will be learned by the…

  4. 75 FR 34170 - Plastic Omnium Automotive Exteriors, LLC, Anderson, SC; Plastic Omnium Automotive Exteriors, LLC...

    Science.gov (United States)

    2010-06-16

    ..., South Carolina. The notice was published in the Federal Register April 23, 2010 (75 FR 21356). The... Employment and Training Administration Plastic Omnium Automotive Exteriors, LLC, Anderson, SC; Plastic Omnium Automotive Exteriors, LLC, Troy, MI; Amended Certification Regarding Eligibility To Apply for...

  5. Automotive-adept: a lightweight assessment method for the automotive Irish software industry

    OpenAIRE

    Mc Caffery, Fergal; Richardson, Ita; Moller, Peter

    2007-01-01

    peer-reviewed In this paper we describe how a lightweight assessment method was developed to educate Irish software small-to-medium sized enterprises (SMEs)1 in relation to becoming automotive software suppliers. The main goal of this assessment method is to provide software SMEs with a SPI path to becoming automotive software suppliers.

  6. EFFECT OF GENDER DIFFERENCE ON BRAKE REACTION TIME

    Directory of Open Access Journals (Sweden)

    Ashok

    2016-02-01

    Full Text Available BACKGROUND OF THE STUDY Reaction time is the time taken to respond to a stimulus or change in the environment. It is a method to assess the time taken from the perception of a stimulus followed by mental processing for a motor response. Reaction time in various day to day activities as in driving a car is very important. Brake reaction time (BRT is the time taken for the driver to respond to visualize an object and to press the brake pedal. It is affected by many features like age, gender, neuromuscular disorders. OBJECTIVE OF THE STUDY Study has been undertaken to compare the BRT in male and female drivers and to analyze the effect of sex difference on Brake reaction time. MATERIALS & METHODS Male and female subjects between the age group of 25 – 35 years with driving license were included. Study is conducted in a stationary car. An in-house built; braking timer is fixed to the electric circuit of the braking system in the car. This device is wirelessly connected to the reaction time software installed in the laptop. The subject is instructed to press the brake pedal when the light changed from red to green in the laptop screen. 5 readings are taken and the mean BRT is recorded. STATISTICAL ANALYSIS & RESULTS Statistical analysis done with unpaired student t test indicates that the BRT was more in the females than the males and was statistically significant (p value - 0007. CONCLUSION Gender difference has a significant effect on BRT and reaction time in female is longer than for the males.

  7. Hierarchical Control Strategy for the Cooperative Braking System of Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Jiankun Peng

    2015-01-01

    Full Text Available This paper provides a hierarchical control strategy for cooperative braking system of an electric vehicle with separated driven axles. Two layers are defined: the top layer is used to optimize the braking stability based on two sliding mode control strategies, namely, the interaxle control mode and signal-axle control strategies; the interaxle control strategy generates the ideal braking force distribution in general braking condition, and the single-axle control strategy can ensure braking safety in emergency braking condition; the bottom layer is used to maximize the regenerative braking energy recovery efficiency with a reallocated braking torque strategy; the reallocated braking torque strategy can recovery braking energy as much as possible in the premise of meeting battery charging power. The simulation results show that the proposed hierarchical control strategy is reasonable and can adapt to different typical road surfaces and load cases; the vehicle braking stability and safety can be guaranteed; furthermore, the regenerative braking energy recovery efficiency can be improved.

  8. 49 CFR 232.503 - Process to introduce new brake system technology.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Process to introduce new brake system technology... Technology § 232.503 Process to introduce new brake system technology. (a) Pursuant to the procedures... brake system technology, prior to implementing the plan. (b) Each railroad shall complete a...

  9. METHODOLOGY FOR PARAMETER CALCULATION OF DISK BRAKE MECHANISMS WITH HYDRAULIC CONTROL

    Directory of Open Access Journals (Sweden)

    O. S. Rukteshel

    2014-11-01

    Full Text Available The paper describes a new methodology for a parameter calculation of a disk brake mechanism with hydraulic control that allows to determine a value of hysteresis losses in a brake at the design stage with high accuracy. A complex analysis for obtaining qualitative and quantitative evaluation of design brake parameter influence on hysteresis value in it is presented in the paper.

  10. 49 CFR 232.207 - Class IA brake tests-1,000-mile inspection.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Class IA brake tests-1,000-mile inspection. 232... Class IA brake tests—1,000-mile inspection. (a) Except as provided in § 232.213, each train shall receive a Class IA brake test performed by a qualified person, as defined in § 232.5, at a location...

  11. Correcting Students' Misconceptions about Automobile Braking Distances and Video Analysis Using Interactive Program Tracker

    Science.gov (United States)

    Hockicko, Peter; Trpišová, Beáta; Ondruš, Ján

    2014-01-01

    The present paper informs about an analysis of students' conceptions about car braking distances and also presents one of the novel methods of learning: an interactive computer program Tracker that we used to analyse the process of braking of a car. The analysis of the students' conceptions about car braking distances consisted in…

  12. Thermal-mechanical coupled analysis of a brake disk rotor

    Science.gov (United States)

    Belhocine, Ali; Bouchetara, Mostefa

    2013-08-01

    The main purpose of this study is to analyze the thermomechanical behavior of the dry contact between the brake disk and pads during the braking phase. The simulation strategy is based on computer code ANSYS11. The modeling of transient temperature in the disk is actually used to identify the factor of geometric design of the disk to install the ventilation system in vehicles The thermal-structural analysis is then used with coupling to determine the deformation and the Von Mises stress established in the disk, the contact pressure distribution in pads. The results are satisfactory when compared to those of the specialized literature.

  13. Hydraulic braking system for loads subjected to impacts and vibrations

    International Nuclear Information System (INIS)

    This invention concerns a hydraulic braking system for loads subjected to impacts and vibrations. These double acting telescopic type hydraulic braking systems possess significant drawbacks linked to possibly important hydraulic leaks due to (a) the use of many dynamic seals in such appliances and (b) the effects of the environment of the system on these seals, particularly when employed in nuclear power stations where the seals reach significant temperatures and are subjected to radiation. Under this invention a remedy is suggested to such drawbacks by integrating means to offset automatically the leaks and the accumulation of hydraulic fluid expansions, as well as facilities to show if such leaks have occurred

  14. Laser engineering of spine discs

    Science.gov (United States)

    Sobol, E.; Zakharkina, O.; Baskov, A.; Shekhter, A.; Borschenko, I.; Guller, A.; Baskov, V.; Omelchenko, A.; Sviridov, A.

    2009-04-01

    The laser engineering of intervertebral discs is one of the branch of medical physics aimed at the development of minimally invasive laser medical techniques based on the effect of the controlled (time- and space-modulated) laser radiation on the structure and the field of mechanical stress of biological tissues. A new method for the laser engineering of the intervertebral discs and the differences of this approach from the existing physical methods of medical treatment are considered. The newly formed tissues of animals and humans are hystologically studied. Possible regeneration processes are discussed. A control system that provides for the treatment efficiency and safety is developed. The new laser medical equipment that is designed for the laser engineering of intervertebral discs is described, and the corresponding results of the clinical application are presented.

  15. Black hole accretion disc impacts

    Science.gov (United States)

    Pihajoki, P.

    2016-04-01

    We present an analytic model for computing the luminosity and spectral evolution of flares caused by a supermassive black hole impacting the accretion disc of another supermassive black hole. Our model includes photon diffusion, emission from optically thin regions and relativistic corrections to the observed spectrum and time-scales. We test the observability of the impact scenario with a simulated population of quasars hosting supermassive black hole binaries. The results indicate that for a moderate binary mass ratio of 0.3, and impact distances of 100 primary Schwarzschild radii, the accretion disc impacts can be expected to equal or exceed the host quasar in brightness at observed wavelength λ = 510 nm up to z = 0.6. We conclude that accretion disc impacts may function as an independent probe for supermassive black hole binaries. We release the code used for computing the model light curves to the community.

  16. Black hole accretion disc impacts

    CERN Document Server

    Pihajoki, Pauli

    2015-01-01

    We present an analytic model for computing the luminosity and spectral evolution of flares caused by a supermassive black hole impacting the accretion disc of another supermassive black hole. Our model includes photon diffusion, emission from optically thin regions and relativistic corrections to the observed spectrum and time-scales. We test the observability of the impact scenario with a simulated population of quasars hosting supermassive black hole binaries. The results indicate that for a moderate binary mass ratio of 0.3, and impact distances of 100 primary Schwarzschild radii, the accretion disc impacts can be expected to equal or exceed the host quasar in brightness at observed wavelength {\\lambda} = 510 nm up to z = 0.6. We conclude that accretion disc impacts may function as an independent probe for supermassive black hole binaries. We release the code used for computing the model light curves to the community.

  17. Improvements in automotive fuel economy

    Energy Technology Data Exchange (ETDEWEB)

    Borcherts, R.H.; Stadler, H.L.; Brehob, W.M.; Auiler, J.E.

    1978-01-01

    Significant improvements in automotive fuel economy can be obtained by reductions in weight, aerodynamic drag (better streamlining) and rolling resistance (tire improvements) as well as improvements in engine and powertrain efficiency. As applied to a six-passenger 3700 lb present day vehicle powered with a 250 CID six-cylinder engine through an automatic transmission, the improvements in EPA M/H fuel economy for 1% reductions in either weight, aerodynamic drag or rolling resistance are projected to be 0.75%, 0.35% and 0.28% respectively. This is under the constraints of constant performance and equal emissions. The extent to which large changes in these parameters can be obtained resulting in significant improvements in fuel economy depends not only upon solving manufacturing and technical problems related to costs but also upon government regulations and customer acceptance in the marketplace. If large reductions in these parameters could be accomplished along with realistic improvements in engine and powertrain efficiency, significant improvements in fuel economy could be achieved.

  18. User discrimination in automotive systems

    Science.gov (United States)

    Makrushin, Andrey; Dittmann, Jana; Vielhauer, Claus; Leich, Marcus

    2011-03-01

    The recently developed dual-view touch screens, which are announced to be installed in cars in a near future, give rise to completely new challenges in human-machine interaction. The automotive system should be able to identify if the driver or the passenger is currently interacting with the touch screen to provide a correct response to the touch. The optical devices, due to availability, acceptance by the users and multifunctional usage, approved to be the most appropriate sensing technology for driver/passenger discrimination. In this work the prototypic optical user discrimination system is implemented in the car simulator and evaluated in the laboratory environment with entirely controlled illumination. Three tests were done for this research. One of them examined if the near-infrared illumination should be switched on around the clock, the second one if there is a difference in discrimination performance between day, twilight and night conditions, and the third one examined how the intensive directional lighting influences the performance of the implemented user discrimination algorithm. Despite the high error rates, the evaluation results show that very simple computer vision algorithms are able to solve complicated user discrimination task. The average error rate of 10.42% (daytime with near-infrared illumination) is a very promising result for optical systems.

  19. Automotive Stirling Engine Development Project

    Science.gov (United States)

    Ernst, William D.; Shaltens, Richard K.

    1997-01-01

    The development and verification of automotive Stirling engine (ASE) component and system technology is described as it evolved through two experimental engine designs: the Mod 1 and the Mod 2. Engine operation and performance and endurance test results for the Mod 1 are summarized. Mod 2 engine and component development progress is traced from the original design through hardware development, laboratory test, and vehicle installation. More than 21,000 hr of testing were accomplished, including 4800 hr with vehicles that were driven more dm 59,000 miles. Mod 2 engine dynamometer tests demonstrated that the engine system configuration had accomplished its performance goals for power (60 kW) and efficiency (38.5%) to within a few percent. Tests with the Mod 2 engine installed in a delivery van demonstrated combined metro-highway fuel economy improvements consistent with engine performance goals and the potential for low emission levels. A modified version of the Mod 2 has been identified as a manufacturable design for an ASE. As part of the ASE project, the Industry Test and Evaluation Program (ITEP), NASA Technology Utilization (TU) project, and the industry-funded Stirling Natural Gas Engine program were undertaken to transfer ASE technology to end users. The results of these technology transfer efforts are also summarized.

  20. Advanced automotive diesel assessment program

    Science.gov (United States)

    Sekar, R.; Tozzi, L.

    1983-01-01

    Cummins Engine Company completed an analytical study to identify an advanced automotive (light duty) diesel (AAD) power plant for a 3,000-pound passenger car. The study resulted in the definition of a revolutionary diesel engine with several novel features. A 3,000-pound car with this engine is predicted to give 96.3, 72.2, and 78.8 MPG in highway, city, and combined highway-city driving, respectively. This compares with current diesel powered cars yielding 41.7, 35.0, and 37.7 MPG. The time for 0-60 MPH acceleration is 13.9 sec. compared to the baseline of 15.2 sec. Four technology areas were identified as crucial in bringing this concept to fruition. They are: (1) part-load preheating, (2) positive displacement compounding, (3) spark assisted diesel combustion system, and (4) piston development for adiabatic, oilless diesel engine. Marketing and planning studies indicate that an aggressive program with significant commitment could result in a production car in 10 years from the date of commencement.

  1. Diagnosis of cervical disc disease

    International Nuclear Information System (INIS)

    High resolution CT easily localized lesions including soft tissues of the bone such as disc protrusion and thickening of the yellow ligament. In all cases, myelography demonstrated compression of the nerve roots of the spinal cord which corresponded to CT findings at the level where plain CT revealed a lesion. However, CT metrizamide myelography demonstrated the lesion more clearly than did conventional myelography. CT metrizamide myelography also outlined compression of the nerve roots satisfactorily and demonstrated compressed findings of the spinal cord in the dynamic study. Thus, high resolution CT was useful for screening of cervical disc disease, and CT metrizamide myelography, for identification of lesions of the nerve roots. (Chiba, N.)

  2. Vertebral osteomyelitis without disc involvement

    Energy Technology Data Exchange (ETDEWEB)

    Kamani, I.; Syed, I.; Saifuddin, A. E-mail: asaifuddin@aol.com; Green, R.; MacSweeney, F

    2004-10-01

    Vertebral osteomyelitis is most commonly due to pyogenic or granulomatous infection and typically results in the combined involvement of the intervertebral disc and adjacent vertebral bodies. Non-infective causes include the related conditions of chronic recurrent multifocal osteomyelitis (CRMO) and SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome. Occasionally, these conditions may present purely within the vertebral body, resulting in various combinations of vertebral marrow oedema and sclerosis, destructive lesions of the vertebral body and pathological vertebral collapse, thus mimicking neoplastic disease. This review illustrates the imaging features of vertebral osteomyelitis without disc involvement, with emphasis on magnetic resonance imaging (MRI) findings.

  3. Research of vehicle steering and braking system based on fuzzy decoupling control%基于模糊解耦控制的车辆转向制动系统研究

    Institute of Scientific and Technical Information of China (English)

    陈燕芹; 李晓旭; 段婷婷

    2014-01-01

    车辆转向系统和制动系统之间存在着很强的速度耦合关系,造成两个系统之间的性能相互影响,使得车辆在转向制动这一工况成了汽车最危险的工况之一。本文结合实际车辆参数建立转向系统的二自由度模型和制动系统的单车轮模型,针对车辆转向制动工况设计了模糊解耦控制器,实现了车辆的转向与制动同时控制。经验证含有模糊解耦控制的车辆转向制动系统具有很好的动态控制效果,并且有很强的鲁棒性和自适应性。%The strong velocity coupling relationships between the automotive steering and braking systems and the systems' performance of mutual influence make the vehicle steering and braking working condition become one of the most dangerous conditions. This paper established a two degree of freedom model of automobile steering systems and a single wheel braking system model based on the actual parameters of vehicle, and designed the fuzzy decoupling controller for controlling simultaneously vehicle steering and braking systems. As a result, the fuzzy decoupling controller of vehicle steering and braking systems has good dynamic control effect, and has strong robustness and adaptability.

  4. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... a total disc replacement arthroplasty on a young patient who has a herniated disc in her neck. ... way in, it’s, you know, I find that patients have very little pain after surgery. And just ...

  5. Hydrodynamic instability in eccentric astrophysical discs

    CERN Document Server

    Barker, Adrian J

    2014-01-01

    Eccentric Keplerian discs are believed to be unstable to three-dimensional hydrodynamical instabilities driven by the time-dependence of fluid properties around an orbit. These instabilities could lead to small-scale turbulence, and ultimately modify the global disc properties. We use a local model of an eccentric disc, derived in a companion paper, to compute the nonlinear vertical ("breathing mode") oscillations of the disc. We then analyse their linear stability to locally axisymmetric disturbances for any disc eccentricity and eccentricity gradient using a numerical Floquet method. In the limit of small departures from a circular reference orbit, the instability of an isothermal disc is explained analytically. We also study analytically the small-scale instability of an eccentric neutrally stratified polytropic disc with any polytropic index using a WKB approximation. We find that eccentric discs are generically unstable to the parametric excitation of small-scale inertial waves. The nonlinear evolution o...

  6. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... spine problems in up to date but this new technology with the use of an artificial disc ... of patients for many, many. Prior to this new technology, we would take out that disc and ...

  7. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... problems in up to date but this new technology with the use of an artificial disc has ... patients for many, many. Prior to this new technology, we would take out that disc and then ...

  8. Artificial Cervical Disc Replacement Improves Mobility

    Science.gov (United States)

    Artificial Cervical Disc Replacement Improves Mobility February 18, 2009 From PinnacleHealth, Harrisburg, PA Welcome to this “OR ... this new technology with the use of an artificial disc has some significant benefits over the previous ...

  9. Planet formation in evolving protoplanetary discs

    OpenAIRE

    Alexander, Richard

    2013-01-01

    I attempt to summarize our knowledge of planet formation in evolving protoplanetary discs. I first review the physics of disc evolution and dispersal. For most of the disc lifetime evolution is driven by accretion and photoevaporation, and I discuss how the interplay between these processes shapes protoplanetary discs. I also discuss the observations that we use to test these models, and the major uncertainties that remain. I will then move on to consider planet formation and migration in evo...

  10. Proceedings: Fossil steam turbine disc cracking workshop

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The objectives of the workshop were to review and consolidate the state of the art of cracking in fossil steam turbine discs; to identify further work needed to assist utilities in evaluating fossil turbine discs subject to SCC. Participants included 18 representatives from utilities, 12 representatives from equipment manufacturing organizations, and 5 consultants. Canadian, European, Japanese, and domestic organizations were represented. Topics included: A Review of GE Fossil Shrunk-On Wheel Stress Corrosion Cracking; Effects on Material and Environmental Factors on SCC of NiCrMoV Rotor Steels; SCC Experience of Shrunk On Discs; Studies on SCC For Steam Turbine Rotor and Disc; Advanced Disc-Type LP Turbine Rotors; Recent Experience of Stress Corrosion Cracking in the LP Discs of Fossil-Fired Reheat Turbines; Stress Corrosion of NiCrMoV LP Disc and Shaft Steels Under Cyclic Loading; NYIT'S Focused Approach for Ultrasonically Scanning Steam Turbine Discs; Probabilistic Assessment of Crack Initiation and Growth in Shrunk-On Discs; Low-Pressure Rotor Disc Cracking and Remaining Life Analysis; Assessment of Probability of Survival of Built Up LP Turbine Rotors With Discs Containing Semi-Circular Keyways; Electric Power Research Institute Turbine Disc Inspection Program; Fossil Turbine Disc Inspections--A Utility Dilemma; In-Service Accumulation of Chemicals in the Keyways and Their Effect on Stress Corrosion Cracking of Turbine Discs; Pitting and Compositional Effects on Stress Corrosion Cracking of Turbine Disc Steels; and TVA's Recent Experience With Inspection and Testing of Shrink-On Discs. Individual papers are processed separately for the data bases.

  11. Computational design of an automotive twist beam

    Directory of Open Access Journals (Sweden)

    Benki Aalae

    2016-07-01

    Full Text Available In recent years, the automotive industry has known a remarkable development in order to satisfy the customer requirements. In this paper, we will study one of the components of the automotive which is the twist beam. The study is focused on the multicriteria design of the automotive twist beam undergoing linear elastic deformation (Hooke׳s law. Indeed, for the design of this automotive part, there are some criteria to be considered as the rigidity (stiffness and the resistance to fatigue. Those two criteria are known to be conflicting, therefore, our aim is to identify the Pareto front of this problem. To do this, we used a Normal Boundary Intersection (NBI algorithm coupling with a radial basis function (RBF metamodel in order to reduce the high calculation time needed for solving the multicriteria design problem. Otherwise, we used the free form deformation (FFD technique for the generation of the 3D shapes of the automotive part studied during the optimization process.

  12. Green competitiveness research on Chinese automotive enterprises

    Directory of Open Access Journals (Sweden)

    Yuanhui Li

    2014-05-01

    Full Text Available Purpose: More and more executives of automobileindustry in China start to recognize the concept of green competitiveness recently. However, relatively less research attention has been devoted to the consideration of measurement. This paper aims to find empirical approach to quantify green competitiveness for automotive enterprises. The connotation of green competitiveness is explored and one suite of evaluation index system has been proposed with four dimensions including environmental, resource, capability and knowledge.Design/methodology/approach: By introducing the factor analysis method, green competitiveness has been measured through an empirical analysis of 24 automotive enterprises within China.Findings: The results indicate that those elements, such as enterprise resource possession and utilization; environment, responsibility and knowledge; profitability; management efficiency, have significant effect on the green competitiveness for automotive enterprises. The further analysis also unveils the advantages and disadvantages of green competitiveness for each company and the direction for improvement.Research limitations/implications: Guide regulators and managers of automobile industry to take some measures to enhance their green competitive advantage.Practical implications: Provide practical methods to measure green competitiveness for automotive enterprises.Originality/value: This paper proposes an evaluation index system of green competitiveness for automotive enterprises. The suggestions of our research will be beneficial to enterprise executives and industry regulators.

  13. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... to delineate the exact trajectory into the disc space. So now he’s found the disc space, what he wants to do is confirm it ... has stuck a marker into this actual disc space, and the next thing he is goes to ...

  14. Spontaneous regression of an intraspinal disc cyst

    Energy Technology Data Exchange (ETDEWEB)

    Demaerel, P.; Eerens, I.; Wilms, G. [University Hospital, Leuven (Belgium). Dept. of Radiology; Goffin, J. [Dept. of Neurosurgery, University Hospitals, Leuven (Belgium)

    2001-11-01

    We present a patient with a so-called disc cyst. Its location in the ventrolateral epidural space and its communication with the herniated disc are clearly shown. The disc cyst developed rapidly and regressed spontaneously. This observation, which has not been reported until now, appears to support focal degeneration with cyst formation as the pathogenesis. (orig.)

  15. T-type channels: release a brake, engage a gear

    Czech Academy of Sciences Publication Activity Database

    Weiss, Norbert; Laconova, L.

    2016-01-01

    Roč. 10, č. 2 (2016), s. 78-80. ISSN 1933-6950 Institutional support: RVO:61388963 Keywords : gating brake * pore opening * Ca(V)3.3 Subject RIV: CE - Biochemistry Impact factor: 2.410, year: 2014 http://www.tandfonline.com/doi/pdf/10.1080/19336950.2015.1106655

  16. Computational thermo-fluid analysis of a disk brake

    Science.gov (United States)

    Takizawa, Kenji; Tezduyar, Tayfun E.; Kuraishi, Takashi; Tabata, Shinichiro; Takagi, Hirokazu

    2016-06-01

    We present computational thermo-fluid analysis of a disk brake, including thermo-fluid analysis of the flow around the brake and heat conduction analysis of the disk. The computational challenges include proper representation of the small-scale thermo-fluid behavior, high-resolution representation of the thermo-fluid boundary layers near the spinning solid surfaces, and bringing the heat transfer coefficient (HTC) calculated in the thermo-fluid analysis of the flow to the heat conduction analysis of the spinning disk. The disk brake model used in the analysis closely represents the actual configuration, and this adds to the computational challenges. The components of the method we have developed for computational analysis of the class of problems with these types of challenges include the Space-Time Variational Multiscale method for coupled incompressible flow and thermal transport, ST Slip Interface method for high-resolution representation of the thermo-fluid boundary layers near spinning solid surfaces, and a set of projection methods for different parts of the disk to bring the HTC calculated in the thermo-fluid analysis. With the HTC coming from the thermo-fluid analysis of the flow around the brake, we do the heat conduction analysis of the disk, from the start of the breaking until the disk spinning stops, demonstrating how the method developed works in computational analysis of this complex and challenging problem.

  17. Oxygen-Diffused Titanium as a Candidate Brake Rotor Material

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Jun [ORNL; Blau, Peter Julian [ORNL; Jolly, Brian C [ORNL

    2009-01-01

    Titanium alloys are one of several candidate materials for the next generation of truck disk brake rotors. Despite their advantages of lightweight relative to cast iron and good strength and corrosion resistance, titanium alloys are unlikely to be satisfactory brake rotor materials unless their friction and wear behavior can be significantly improved. In this study, a surface engineering process oxygen diffusion was applied to titanium rotors and has shown very encouraging results. The oxygen diffused Ti-6Al-4V (OD-Ti) was tested on a sub-scale brake tester against a flat block of commercial brake lining material and benchmarked against several other Ti-based materials, including untreated Ti-6Al-4V, ceramic particle-reinforced Ti composites (MMCs), and a thermal-spray-coated Ti alloy. With respect to friction, the OD-Ti outperformed all other candidate materials under the imposed test conditions with the friction coefficient remaining within a desirable range of 0.35-0.50, even under the harshest conditions when the disk surface temperature reached nearly 600 C. In addition, the OD-Ti showed significantly improved wear-resistance over the non-treated one and was even better than the Ti-based composite materials.

  18. Electromechanical design and optimization of electromagnetic brake for rail vehicles

    Czech Academy of Sciences Publication Activity Database

    Doležel, Ivo; Moravec, J.; Sedláček, J.; Ulrych, B.

    Lausanne: House EPFL Lausanne, 2005, s. 1-5. [Symposium on Advanced Electromechanical Motion Systems /6/ [0204121]. Lausanne (CH), 27.09.2005-29.09.2005] Institutional research plan: CEZ:AV0Z20570509 Keywords : optimization electromagnetic brake Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  19. A Laboratory Activity on the Eddy Current Brake

    Science.gov (United States)

    Molina-Bolivar, J. A.; Abella-Palacios, A. J.

    2012-01-01

    The aim of this paper is to introduce a simple and low-cost experimental setup that can be used to study the eddy current brake, which considers the motion of a sliding magnet on an inclined conducting plane in terms of basic physical principles. We present a set of quantitative experiments performed to study the influence of the geometrical and…

  20. Non-resonant magnetic braking on JET and TEXTOR

    DEFF Research Database (Denmark)

    Sun, Y.; Liang, Y.; Shaing, K.C.;

    2012-01-01

    The non-resonant magnetic braking effect induced by a non-axisymmetric magnetic perturbation is investigated on JET and TEXTOR. The collisionality dependence of the torque induced by the n = 1, where n is the toroidal mode number, magnetic perturbation generated by the error field correction coil...

  1. 16 CFR 1512.5 - Requirements for braking system.

    Science.gov (United States)

    2010-01-01

    ... as determined by the equivalent ground speed specified in § 1512.18(d)(2)(vi). (2) Hand lever access. Hand lever mechanisms shall be located on the handlebars in a position that is readily accessible to... dimension between the brake hand lever and the handlebars in the plane containing the centerlines of...

  2. Analysis of the surface layer of the brake disk

    Czech Academy of Sciences Publication Activity Database

    Švábenská, Eva; Roupcová, Pavla; Podstranská, Ivana; Petr, M.; Filip, J.; Schneeweiss, Oldřich

    Ostrava : TANGER Ltd, 2015. ISBN 978-80-87294-58-1. [METAL 2015. International Conference on Metallurgy and Materials /24./. Brno (CZ), 03.06.2015-05.06.2015] R&D Projects: GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : grey cast iron * brake disk * microstructure analysis * surface layer Subject RIV: JG - Metallurgy

  3. Braking index of isolated pulsars: open questions and ways forward

    CERN Document Server

    Hamil, Oliver

    2015-01-01

    Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of debate, the commonly accepted view is that it arises either through emission of magnetic dipole radiation (MDR) from a rotating magnetized body, through emission of a relativistic particle wind, or via higher order magnetic multipole or gravitational quadrupole radiation. The calculated energy loss by a rotating pulsar is model dependent and leads to the power law $\\dot{\\Omega}$ = -K $\\Omega^{\\rm n}$ where $n$ is called the braking index. The theoretical value for braking index is $n = 1, 3, 5$ for wind, MDR, quadrupole radiation respectively. The accepted view is that pulsar braking is strongly dominated by MDR. Highly precise observations of isolated pulsars yield braking index values in the range $1 < n < 2.8$ which are consistently less than the value pred...

  4. Can Dark Matter explain the Braking Index of Neutron Stars?

    CERN Document Server

    Kouvaris, Chris

    2014-01-01

    We explore a new mechanism of slowing down the rotation of neutron stars via accretion of millicharged dark matter. We find that this mechanism yields pulsar braking indices that can be substantially smaller than the standard $n\\sim 3$ of the magnetic dipole radiation model for millicharged dark matter particles that are not excluded by existing experimental constraints thus accommodating existing observations.

  5. Wear and related characteristics of an aircraft tire during braking

    Science.gov (United States)

    Mccarty, J. L.

    1972-01-01

    Wear and related characteristics of friction and temperature developed during braking of size 22 x 5.5, type aircraft tires are studied. The testing technique involved gearing the tire to a driving wheel of a ground vehicle to provide operations at constant slip ratios on asphalt, concrete, and slurry-seal surfaces. Data were obtained over the range of slip ratios generally attributed to an aircraft braking system during dry runway operations. The results show that the cumulative tire wear varies linearly with distance traveled and the wear rate increases with increasing slip ratio and is influenced by the runway-surface character. Differences in the wear rates associated with the various surfaces suggest that runways can be rated on the basis of tire wear. The results also show that the friction coefficients developed during fixed-slip-ratio operations are in good agreement with those obtained by other investigators during cyclic braking, in that the dry friction is insensitive to the tire tread temperature is shown to increase with increasing slip ratio and, at the higher ratios, to be greater during braking on asphalt and slurry seal than on concrete.

  6. Can dark matter explain the braking index of neutron stars?

    DEFF Research Database (Denmark)

    Kouvaris, C.; Perez-Garcia, M. A.

    2014-01-01

    We explore a new mechanism of slowing down the rotation of neutron stars via accretion of millicharged dark matter. We find that this mechanism yields pulsar braking indices that can be substantially smaller than the standard n similar to 3 of the magnetic dipole radiation model for millicharged...... dark matter particles that are not excluded by existing experimental constraints thus accommodating existing observations....

  7. Chinese Enterprises Slams the Brakes on Acquisition of Overseas Mines

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>On June 25,China Mining Association revealed that,as of the middle of June,Chinese enterprises slammed the brakes on acquisition of overseas mines.There are only 53 overseas mine acquisition cases so far this year,

  8. Electromagnetic Levitation of a Disc

    Science.gov (United States)

    Valle, R.; Neves, F.; de Andrade, R., Jr.; Stephan, R. M.

    2012-01-01

    This paper presents a teaching experiment that explores the levitation of a disc of ferromagnetic material in the presence of the magnetic field produced by a single electromagnet. In comparison to the classical experiment of the levitation of a sphere, the main advantage of the proposed laboratory bench is that the uniform magnetic field…

  9. The Prospect of Mass Customisation in the Chinese Automotive Industry

    OpenAIRE

    Dong, Xihan

    2011-01-01

    The automotive industry is one of the largest manufacturing industries and the development of a country’s automotive industry can represent its economy to some extent. Because of the fierce competition in the automotive industry, customers have more choices and they cannot be satisfied with standard products any more. Therefore, some global automotive manufacturers implement mass customisation as their production strategy which aims to provide customised automobiles according to customers’ re...

  10. Innovation in the Automotive Sector of the Philippines

    OpenAIRE

    Quimba, Francis Mark A.; Rosellon, Maureen Ane D.

    2011-01-01

    The performance of the Philippine automotive industry has steadily improved after the Asian crisis. However, relative to the performance of the automotive industry in other countries, the automotive sector in the country has languished. To understand the challenges being faced by the automotive assemblers, as well as parts and components manufacturers, the innovation capability and activities of selected establishments are analyzed following the framework developed by Bessant. This paper find...

  11. Theoretical and experimental studies on a magnetorheological brake operating under compression plus shear mode

    Science.gov (United States)

    Sarkar, C.; Hirani, H.

    2013-11-01

    The torque characteristics of magnetorheological brakes, consisting of rotating disks immersed in a MR fluid and enclosed in an electromagnetic casing, are controlled by regulating the yield stress of the MR fluid. An increase in yield stress increases the braking torque, which means that the higher the yield strength of the MR fluid, the better the performance of the MR brake will be. In the present research an application of compressive force on MR fluid has been proposed to increase the torque capacity of MR brakes. The mathematical expressions to estimate the torque values for MR brake, operating under compression plus shear mode accounting Herschel-Bulkley shear thinning model, have been detailed. The required compressive force on MR fluid of the proposed brake has been applied using an electromagnetic actuator. The development of a single-plate MR disk brake and an experimental test rig are described. Experiments have been performed to illustrate braking torque under different control currents (0.0-2.0 A). The torque results have been plotted and compared with theoretical study. Experimental results as well as theoretical calculations indicate that the braking torque of the proposed MR brake is higher than that of the MR brake operating only under shear.

  12. Theoretical and experimental studies on a magnetorheological brake operating under compression plus shear mode

    International Nuclear Information System (INIS)

    The torque characteristics of magnetorheological brakes, consisting of rotating disks immersed in a MR fluid and enclosed in an electromagnetic casing, are controlled by regulating the yield stress of the MR fluid. An increase in yield stress increases the braking torque, which means that the higher the yield strength of the MR fluid, the better the performance of the MR brake will be. In the present research an application of compressive force on MR fluid has been proposed to increase the torque capacity of MR brakes. The mathematical expressions to estimate the torque values for MR brake, operating under compression plus shear mode accounting Herschel–Bulkley shear thinning model, have been detailed. The required compressive force on MR fluid of the proposed brake has been applied using an electromagnetic actuator. The development of a single-plate MR disk brake and an experimental test rig are described. Experiments have been performed to illustrate braking torque under different control currents (0.0–2.0 A). The torque results have been plotted and compared with theoretical study. Experimental results as well as theoretical calculations indicate that the braking torque of the proposed MR brake is higher than that of the MR brake operating only under shear. (paper)

  13. Lumbar Disc Degenerative Disease: Disc Degeneration Symptoms and Magnetic Resonance Image Findings

    OpenAIRE

    Saleem, Shafaq; Aslam, Hafiz Muhammad; Rehmani, Muhammad Asim Khan; Raees, Aisha; Alvi, Arsalan Ahmad; Ashraf, Junaid

    2013-01-01

    Study Design Cross sectional and observational. Purpose To evaluate the different aspects of lumbar disc degenerative disc disease and relate them with magnetic resonance image (MRI) findings and symptoms. Overview of Literature Lumbar disc degenerative disease has now been proven as the most common cause of low back pain throughout the world. It may present as disc herniation, lumbar spinal stenosis, facet joint arthropathy or any combination. Presenting symptoms of lumbar disc degeneration ...

  14. Spontaneous Regression of Herniated Lumbar Disc with New Disc Protrusion in the Adjacent Level

    OpenAIRE

    Hakan, Tayfun; Gürcan, Serkan

    2016-01-01

    Spontaneous regression of herniated lumbar discs was reported occasionally. The mechanisms proposed for regression of disc herniation are still incomplete. This paper describes and discusses a case of spontaneous regression of herniated lumbar discs with a new disc protrusion in the adjacent level. A 41-year-old man was admitted with radiating pain and numbness in the left lower extremity with a left posterolateral disc extrusion at L5-S1 level. He was admitted to hospital with low back pain ...

  15. Study on antilock brake system with elastic membrane vibration generated by controlled solenoid excitation

    Science.gov (United States)

    Wibowo, Zakaria, Lambang, Lullus; Triyono, Muhayat, Nurul

    2016-03-01

    The most effective chassis control system for improving vehicle safety during severe braking is anti-lock braking system (ABS). Antilock effect can be gained by vibrate the pad brake at 7 to 20 cycle per second. The aim of this study is to design a new method of antilock braking system with membrane elastic vibrated by solenoid. The influence of the pressure fluctuations of brake fluid is investigated. Vibration data is collected using a small portable accelerometer-slam stick. The experiment results that the vibration of brake pad caused by controlled solenoid excitation at 10 Hz is obtained by our new method. The result of measurements can be altered by varying brake fluid pressure.

  16. Optimization and optimal control in automotive systems

    CERN Document Server

    Kolmanovsky, Ilya; Steinbuch, Maarten; Re, Luigi

    2014-01-01

    This book demonstrates the use of the optimization techniques that are becoming essential to meet the increasing stringency and variety of requirements for automotive systems. It shows the reader how to move away from earlier  approaches, based on some degree of heuristics, to the use of  more and more common systematic methods. Even systematic methods can be developed and applied in a large number of forms so the text collects contributions from across the theory, methods and real-world automotive applications of optimization. Greater fuel economy, significant reductions in permissible emissions, new drivability requirements and the generally increasing complexity of automotive systems are among the criteria that the contributing authors set themselves to meet. In many cases multiple and often conflicting requirements give rise to multi-objective constrained optimization problems which are also considered. Some of these problems fall into the domain of the traditional multi-disciplinary optimization applie...

  17. Disc degeneration: current surgical options

    Directory of Open Access Journals (Sweden)

    C Schizas

    2010-10-01

    Full Text Available Chronic low back pain attributed to lumbar disc degeneration poses a serious challenge to physicians. Surgery may be indicated in selected cases following failure of appropriate conservative treatment. For decades, the only surgical option has been spinal fusion, but its results have been inconsistent. Some prospective trials show superiority over usual conservative measures while others fail to demonstrate its advantages. In an effort to improve results of fusion and to decrease the incidence of adjacent segment degeneration, total disc replacement techniques have been introduced and studied extensively. Short-term results have shown superiority over some fusion techniques. Mid-term results however tend to show that this approach yields results equivalent to those of spinal fusion. Nucleus replacement has gained some popularity initially, but evidence on its efficacy is scarce. Dynamic stabilisation, a technique involving less rigid implants than in spinal fusion and performed without the need for bone grafting, represents another surgical option. Evidence again is lacking on its superiority over other surgical strategies and conservative measures. Insertion of interspinous devices posteriorly, aiming at redistributing loads and relieving pain, has been used as an adjunct to disc removal surgery for disc herniation. To date however, there is no clear evidence on their efficacy. Minimally invasive intradiscal thermocoagulation techniques have also been tried, but evidence of their effectiveness is questioned. Surgery using novel biological solutions may be the future of discogenic pain treatment. Collaboration between clinicians and basic scientists in this multidisciplinary field will undoubtedly shape the future of treating symptomatic disc degeneration.

  18. Synthesis and Characterization of Antifriction Magnetorheological Fluids for Brake

    Directory of Open Access Journals (Sweden)

    Chiranjit Sarkar

    2013-07-01

    Full Text Available Magnetorheological (MR fluids are smart materials with shear strength ranging between zero to 100 kPa under the influence of magnetic field. The present paper discusses the synthesis of MR fluid and its application in brake. In MR brake, gap between stator and rotor is filled with low (off-state viscosity MR fluid. On the application of magnetic field, MR fluid changes its state from liquid to semi-solid by aligning magnetic particles in chains. Due to such chaining action, yield strength of fluid increases, friction between stator and rotor increases and fulfils the braking function. The strength of magnetic particle is a function of relative speed between stator and rotor, applied magnetic field, and volume percentage of magnetic particle. In this study antifriction (off-state and strong chain (on-state CI based MR fluid has been prepared by mixing oleic acid as antifriction additives and tetramethylammonium hydroxide as surfactant to reduce the agglomeration of the MR fluid. Yield strengths of the synthesized MR fluid in on-state and off-state have been compared with commercially available MRF 241ES fluid. A flywheel based MR brake experimental setup has been developed to analyze the performance of designed and developed MR brake.Results show that synthesized MR fluid is stronger and faster in response compared to MRF 241ES fluid.Defence Science Journal, 2013, 63(4, pp.408-412, DOI:http://dx.doi.org/10.14429/dsj.63.2633

  19. CT findings of lumbar intervertebral disc: II. Disc herniation (HNP)

    International Nuclear Information System (INIS)

    In lumbar region the epidural fat pad is relatively abundant so that CT can provides sufficient information in diagnosis of lumbar HNP. Many authors have reported on the CT findings of HNP such as focal nodular protrusion of the posterior disc margin, obliteration of epidural fat pad, impingement of dural sac and nerve root, swelling of nerve root, soft tissue density in the spinal canal and calcification of disc. However there was so previous report describing incidence and reliability of the findings. It is the purpose of the present study to survey the frequency, reliability, and limitation of these CT findings. The clinical material was consisted of 30 operatively proven cases of HNP of the lumbar spine. Each lumbar CT scan was reviewed retrospectively and the findings were analysed by two radiologists independently. There were 20 males and 10 females and the mean age was 36.7 years. Involvement of L4-S5 level was 2.3 times more frequent than that of L5-S1 level. Of 30 cases, 22 were unilateral posterolateral types and 8 cases central or unilateral far lateral types. CT findings observed were nodular protrusion of the posterior margin of the disc, obliteration of epidural fat pad, impingement of dural sac or nerve root, soft tissue density in the spinal canal and calcification in the posterior portion of the protruded disc, in order of decreasing frequency. The conclusions are follows: 1. Nodular protrusion of the posterior disc margin accompanied by obliteration of epidural fat pad was observed in every case. The former findings was designated as direct sign and the latter indirect. 2. Obliteration of the epidural fat appears to be significant in lateral recesses especially when it occurs unilaterally. This was not true, however, in the centrally located fat pad. 3. Impingement of the dural sac and nerve root were observed in 90% and 67%, respectively, and were very helpful in establishing HNP diagnosis when the direct and indirect signs were equivocal

  20. 16 CFR 306.5 - Automotive fuel rating.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Automotive fuel rating. 306.5 Section 306.5 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS AUTOMOTIVE FUEL RATINGS, CERTIFICATION AND POSTING Duties of Refiners, Importers and Producers § 306.5 Automotive...

  1. Best Practices in School-to-Careers: The Automotive Industry.

    Science.gov (United States)

    National Employer Leadership Council, Washington, DC.

    This document highlights the school-to-careers (STC) partnerships connecting workplace experiences to classroom learning to prepare students for successful employment in the automotive industry. First, the current state of the automotive industry is reviewed and the role of STC in addressing automotive service needs is explained. Next, the…

  2. Can Distance Learning Be Used to Teach Automotive Management Skills?

    Science.gov (United States)

    Noto, Teresa L.

    2011-01-01

    Today's automotive college students will shape the future of the automobile industry. The success of college-level automotive programs has long been dependent on the students' ability to participate in hands-on classroom based interactions. In this article, distance learning and how it can be used to teach automotive management skills, as well as…

  3. 25 CFR 117.10 - Purchase of automotive equipment.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Purchase of automotive equipment. 117.10 Section 117.10... COMPETENCY § 117.10 Purchase of automotive equipment. The superintendent may disburse from the surplus funds of an adult Indian not to exceed $2,000 for the purchase of automotive equipment when the...

  4. MR imaging findings of a sequestered disc in the lumbar spine: a comparison with an extruded disc

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Su Youn; Park, Ji Seon; Ryu, Kyung Nam [Kyung Hee University Medical Center, Seoul (Korea, Republic of); Jin, Wook [Kyung Hee University East-west Neo Medical Center, Seoul (Korea, Republic of)

    2007-10-15

    To compare the MR findings of a sequestered disc with an extruded disc. MR images of 28 patients with a sequestered disc and 18 patients with an extruded disc were retrospectively reviewed. Patients with sequestered discs were divided into two groups whether definite separation from the parent disc was or was not seen. In the latter group (definite separation not seen) and the extruded disc group of patients, the signal intensities of the herniated discs were compared with the signal intensities of the parent discs and were evaluated on T1-and T2-weighted images. We also assessed the presence of a notch within the herniated disc. In the sequestered disc group of patients (28 discs), only 5 discs (18%) showed obvious separation from the parent disc. Among the remaining 23 discs with indefinite separation, the notch was visible in 14 discs (61%) and 9 discs (39%) had no notch. In the extruded disc group (18 discs), the notch was visible in 2 (11%) discs and the difference between the two groups was statistically significant ({rho} 0.0002). The signal intensities of the herniated discs on T1-weighted images were isointense in both the sequestered and extruded discs. The difference of incidence of high signal intensities on T2-weighted images was not statistically significant ({rho} = 0.125). It is necessary to consider the possibility of the presence of a sequestered disc when a herniated disc material shows a notch.

  5. Fatigue life of automotive rubber jounce bumper

    International Nuclear Information System (INIS)

    It is evident that most rubber components in the automotive industry are subjected to repetitive loading. Vigorous research is needed towards improving the safety and reliability of the components. The study was done on an automotive rubber jounce bumper with a rubber hardness of 60 IRHD. The test was conducted in displacement-controlled environment under compressive load. The existing models by Kim, Harbour, Woo and Li were adopted to predict the fatigue life. The experimental results show strong similarities with the predicted models.

  6. Fatigue life of automotive rubber jounce bumper

    Energy Technology Data Exchange (ETDEWEB)

    Sidhu, R S [Automotive Engineering Unit, Institute of Advanced Technology, University Putra Malaysia, 43400, UPM Serdang, Selangor (Malaysia); Ali, Aidy, E-mail: aidy@eng.upm.edu.my [Department of Mechanical and Manufacturing Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang Selangor (Malaysia)

    2010-05-15

    It is evident that most rubber components in the automotive industry are subjected to repetitive loading. Vigorous research is needed towards improving the safety and reliability of the components. The study was done on an automotive rubber jounce bumper with a rubber hardness of 60 IRHD. The test was conducted in displacement-controlled environment under compressive load. The existing models by Kim, Harbour, Woo and Li were adopted to predict the fatigue life. The experimental results show strong similarities with the predicted models.

  7. Quartz angular rate sensor for automotive navigation

    Energy Technology Data Exchange (ETDEWEB)

    Nozoe, Toshiyuki; Ichinose, Toshihiko; Kawasaki, Syusaku; Hatanaka, Masakazu; Kuroda, Keisuke [Matsushita Electronic Components Co. Ltd. (Japan); Yamamoto, Kohji; Ogata, Motoki; Takeno, Shoichi [Fukui Matsushita Electric Co. Ltd. (Japan); Ishihara, Minoru; Ishii, Tadashi; Umeki, Mitoshi [Nihonn Denpa Kogyo Co. Ltd. (Japan)

    1999-07-01

    Many of the recent automotive navigation systems are introducing an angular rate sensor that detect vehicle yaw in their system due to the advantage of higher accuracy, in addition to a conventional GPS (Global Positioning System) and vehicle speed signals. Though there are a couple of other methods to get a vehicle direction information, the angular rate sensor is the most suitable device as a gyro in accuracy and reliability point of view. Matsushita developed a new compact angular rate sensor using quartz crystal for automotive navigation systems. The sensor's operation is based upon Coriolis force imposed on a vibrating quartz tuning fork. (orig.)

  8. Automotive cooling systems based on metal hydrides

    OpenAIRE

    Linder, Marc

    2010-01-01

    The present work focuses on metal hydride sorption systems as an alternative technology for automotive air-conditioning systems. Although this technology offers the possibility to increase the energy efficiency of a car (by utilising waste heat) and consequently reduces the CO2 emissions, its weight specific cooling power has so far been the main obstacle for an automotive application. Based on investigations of various metal hydrides, two alloys (LmNi4.91Sn0.15 and Ti0.99Zr0.01V0.43Fe0.09Cr0...

  9. Innovation and Entrepreneurship in the Automotive Business

    DEFF Research Database (Denmark)

    2011-01-01

    The global automotive business is one of the most competitive environment you can imagine. As an independent inventor or as a small development company it is very challenging to be successful in implementing new ideas and components. In this mature and somewhat conservative technical environment...... address you will have a much better access the decision making process and get enough interest for a potential business deal. After 20 years as a supplier of engineering services to the automotive industry and 10 years as head of Global R&D at Scania CV AB, I have experienced pros and cons both from a...

  10. Nanotechnology impact on the automotive industry.

    Science.gov (United States)

    Wong, Kaufui V; Paddon, Patrick A

    2014-01-01

    Nanotechnology has been implemented widely in the automotive industry. This technology is particularly useful in coatings, fabrics, structural materials, fluids, lubricants, tires, and preliminary applications in smart glass/windows and video display systems. A special sub-class of improved materials, alternative energy, has also seen a boost from advances in nanotechnology, and continues to be an active research area. A correlation exists in the automotive industry between the areas with increased nanotechnology incorporation and those with increased profit margins via improvements and customer demands. PMID:25360613

  11. Accretion and plasma outflow from dissipationless discs

    OpenAIRE

    Bogovalov, Sergei; Kelner, Stanislav

    2008-01-01

    We consider an extreme case of disc accretion onto a gravitating centre when the viscosity in the disc is negligible. The angular momentum and the rotational energy of the accreted matter is carried out by a magnetized wind outflowing from the disc. The outflow of matter from the disc occurs due to the Blandford & Payne(1982) centrifugal mechanism. The disc is assumed to be cold. Accretion and outflow are connected by the conservation of the energy, mass and the angular momentum. The basic pr...

  12. On the warping of Be star discs

    OpenAIRE

    Porter, John M.

    1998-01-01

    The theory of radiatively-induced warps in accretion discs is applied to the discs of Be stars. It is found that these discs may develop warps in their inner regions, although once the warp amplitude is large enough then the interaction between the disc and fast radiatively-driven wind will determine its evolution. The warping is shown to be more important for later than earlier B stars. Although the interaction of the fast-wind with the disc will limit the amplitude of the warp, it cannot dr...

  13. Three-level cervical disc herniation

    Directory of Open Access Journals (Sweden)

    St. Iencean Andrei

    2015-09-01

    Full Text Available Multilevel cervical degenerative disc disease is well known in the cervical spine pathology, with radicular syndromes or cervical myelopathy. One or two level cervical herniated disc is common in adult and multilevel cervical degenerative disc herniation is common in the elderly, with spinal stenosis, and have the same cause: the gradual degeneration of the disc. We report the case of a patient with two level cervical disc herniation (C4 – C5 and C5 – C6 treated by anterior cervical microdiscectomy both levels and fusion at C5 – C6; after five years the patient returned with left C7 radiculopathy and MRI provided the image of a left C6 – C7 disc herniation, he underwent an anterior microsurgical discectomy with rapid relief of symptoms. Three-level cervical herniated disc are rare in adults, and the anterior microdiscectomy with or without fusion solve this pathology.

  14. Numerical simulations of disc-planet interactions

    CERN Document Server

    Paardekooper, Richard P Nelson Sijme-Jan

    2009-01-01

    The gravitational interaction between a protoplanetary disc and planetary sized bodies that form within it leads to the exchange of angular momentum, resulting in migration of the planets and possible gap formation in the disc for more massive planets. In this article, we review the basic theory of disc-planet interactions, and discuss the results of recent numerical simulations of planets embedded in protoplanetary discs. We consider the migration of low mass planets and recent developments in our understanding of so-called type I migration when a fuller treatment of the disc thermodynamics is included. We discuss the runaway migration of intermediate mass planets (so-called type III migration), and the migration of giant planets (type II migration) and the associated gap formation in the disc. The availability of high performance computing facilities has enabled global simulations of magnetised, turbulent discs to be computed, and we discuss recent results for both low and high mass planets embedded in such...

  15. 19 CFR 10.84 - Automotive vehicles and articles for use as original equipment in the manufacture of automotive...

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Automotive vehicles and articles for use as original equipment in the manufacture of automotive vehicles. 10.84 Section 10.84 Customs Duties U.S... CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Automotive Products § 10.84...

  16. Variable friction device for structural control based on duo-servo vehicle brake: Modeling and experimental validation

    Science.gov (United States)

    Cao, Liang; Downey, Austin; Laflamme, Simon; Taylor, Douglas; Ricles, James

    2015-07-01

    Supplemental damping can be used as a cost-effective method to reduce structural vibrations. In particular, passive systems are now widely accepted and have numerous applications in the field. However, they are typically tuned to specific excitations and their performances are bandwidth-limited. A solution is to use semi-active devices, which have shown to be capable of substantially enhanced mitigation performance. The authors have recently proposed a new type of semi-active device, which consists of a variable friction mechanism based on a vehicle duo-servo drum brake, a mechanically robust and reliable technology. The theoretical performance of the proposed device has been previously demonstrated via numerical simulations. In this paper, we further the understanding of the device, termed Modified Friction Device (MFD) by fabricating a small scale prototype and characterizing its dynamic behavior. While the dynamics of friction is well understood for automotive braking technology, we investigate for the first time the dynamic behavior of this friction mechanism at low displacements and velocities, in both forward and backward directions, under various hydraulic pressures. A modified 3-stage dynamic model is introduced. A LuGre friction model is used to characterize the friction zone (Stage 1), and two pure stiffness regions to characterize the dynamics of the MFD once the rotation is reversed and the braking shoes are sticking to the drum (Stage 2) and the rapid build up of forces once the shoes are held by the anchor pin (Stage 3). The proposed model is identified experimentally by subjecting the prototype to harmonic excitations. It is found that the proposed model can be used to characterize the dynamics of the MFD, and that the largest fitting error arises at low velocity under low pressure input. The model is then verified by subjecting the MFD to two different earthquake excitations under different pressure inputs. The model is capable of tracking the

  17. Research progress of aluminum alloy automotive sheet and application technology

    Institute of Scientific and Technical Information of China (English)

    Ma Mingtu; You Jianghai; Lu Hongzhou; Wang Zhiwen

    2012-01-01

    Pretrcatment technology is deeply discussed to explain its importance in guaranteeing properties and form- ability of aluminum alloy automotive sheet. Some typical applications of aluminum alloy automotive sheet to automotive industry are listed. Based on the author's knowledge and recognition and research progress presently, the important re- search contents about aluminum alloy automotive sheet are emphasized. Reducing cost and price of sheet and going deeply into application research are the main work for expending the application of aluminum alloy automotive sheet in the automobile.

  18. Retrograde binaries of massive black holes in circumbinary accretion discs

    Science.gov (United States)

    Amaro-Seoane, Pau; Maureira-Fredes, Cristián; Dotti, Massimo; Colpi, Monica

    2016-06-01

    Context. We explore the hardening of a massive black hole binary embedded in a circumbinary gas disc under a specific circumstance: when the binary and the gas are coplanar and the gas is counter-rotating. The binary has unequal mass and the interaction of the gas with the lighter secondary black hole is the main cause of the braking torque on the binary that shrinks with time. The secondary black hole, revolving in the direction opposite to the gas, experiences a drag from gas-dynamical friction and from direct accretion of part of it. Aims: In this paper, using two-dimensional (2D) hydrodynamical grid simulations we investigate the effect of changing the accretion prescriptions on the dynamics of the secondary black hole, which in turn affect the binary hardening and eccentricity evolution. Methods: We find that realistic accretion prescriptions lead to results that differ from those inferred assuming accretion of all the gas within the Roche Lobe of the secondary black hole. Results: When considering gas accretion within the gravitational influence radius of the secondary black hole (which is smaller than the Roche Lobe radius) to better describe gas inflows, the shrinking of the binary is slower. In addition, in this case, a smaller amount of accreted mass is required to reduce the binary separation by the same amount. Different accretion prescriptions result in different discs' surface densities, which alter the black hole's dynamics back. Full 3D Smoothed-particle hydrodynamics realizations of a number of representative cases, run over a shorter interval of time, validate the general trends observed in the less computationally demanding 2D simulations. Conclusions: Initially circular black hole binaries increase their eccentricity only slightly, which then oscillates around small values (<0.1) while they harden. By contrast, initially eccentric binaries become more and more eccentric. A semi-analytical model describing the black hole's dynamics under

  19. Heavy and Overweight Vehicle Brake Testing: Five-Axle Combination Tractor-Flatbed Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Lascurain, Mary Beth [ORNL; Capps, Gary J [ORNL; Franzese, Oscar [ORNL

    2013-10-01

    The Federal Motor Carrier Safety Administration, in coordination with the Federal Highway Administration, sponsored the Heavy and Overweight Vehicle Brake Testing (HOVBT) program in order to provide information about the effect of gross vehicle weight (GVW) on braking performance. Because the Federal Motor Carrier Safety Regulations limit the number of braking system defects that may exist for a vehicle to be allowed to operate on the roadways, the examination of the effect of brake defects on brake performance for increased loads is also relevant. The HOVBT program seeks to provide relevant information to policy makers responsible for establishing load limits, beginning with providing test data for a combination tractor/trailer. This testing was conducted on a five-axle combination vehicle with tractor brakes meeting the Reduced Stopping Distance requirement rulemaking. This report provides a summary of the testing activities, the results of various analyses of the data, and recommendations for future research. Following a complete brake rebuild, instrumentation, and brake burnish, stopping tests were performed from 20 and 40 mph with various brake application pressures (15 psi, 25 psi, 35 psi, 45 psi, 55 psi, and full system pressure). These tests were conducted for various brake conditions at the following GVWs: 60,000, 80,000, 91,000, 97,000, 106,000, and 116,000 lb. The 80,000-lb GVWs included both balanced and unbalanced loads. The condition of the braking system was also varied. To introduce these defects, brakes (none, forward drive axle, or rear trailer axle) were made inoperative. In addition to the stopping tests, performance-based brake tests were conducted for the various loading and brake conditions. Analysis of the stopping test data showed the stopping distance to increase with load (as expected) and also showed that more braking force was generated by the drive axle brakes than the trailer axle brakes. The constant-pressure stopping test data

  20. Degradation of automotive materials in palm biodiesel

    International Nuclear Information System (INIS)

    As compared to petroleum diesel, biodiesel is more corrosive for automotive materials. Studies on the characterization of corrosion products of fuel exposed automotive materials are scarce. Automotive fuel system and engine components are made from different ferrous and non-ferrous materials. The present study aims to investigate the corrosion products of different types of automotive materials such as copper, brass, aluminum and cast iron upon exposure to diesel and palm biodiesel. Changes in fuel properties due to exposure of different materials were also examined. Degradation of metal surface was characterized by digital camera, SEM/EDS and X-ray diffraction (XRD). Fuel properties were examined by measuring TAN (total acid number), density and viscosity. Among the metal investigated, copper is found to be least resistant in biodiesel and formed comparatively more corrosion products than other metals. Upon exposure of metals in biodiesel, TAN number crosses the limit given by standard while density and viscosity remain within the acceptable range of limit. -- Highlights: ► Order of incompatible metals in palm biodiesel: copper > brass > aluminum > cast iron. ► The possible reactions for the degradation of copper and cast iron have been discussed. ► For metal exposed biodiesel, only TAN number crosses the limit while density and viscosity remain within the limit. ► Copper and copper based alloy (brass) increase TAN number comparatively more than other metals.

  1. Aero and vibroacoustics of automotive turbochargers

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen-Schaefer, Hung [Bosch Mahle Turbo Systems GmbH, Stuttgart (Germany)

    2013-02-01

    First book about the aeroacoustics of automotive turbochargers. Author of the book ''Rotordynamics of Automotive Turbochargers'', Springer, 2012. Written by an R and D expert in the turbocharger industry. Aero and Vibroacoustics of Automotive Turbochargers is a topic involving aspects from the working fields of thermodynamics of turbomachinery, aerodynamics, rotordynamics, and noise propagation computation. In this broadly interdisciplinary subject, thermodynamics of turbomachinery is used to design the turbocharger and to determine its operating conditions. Aerodynamics is needed to study the compressor flow dynamics and flow instabilities of rotating stall and surge, which can produce growling and whining-type noises. Rotordynamics is necessary to study rotor unbalance and self-excited oil-whirl instabilities, which lead to whistling and constant tone-type noises in rotating floating oil-film type bearings. For the special case of turbochargers using ball bearings, some high-order harmonic and wear noises also manifest in the rotor operating range. Lastly, noise propagation computation, based on Lighthill's analogy, is required to investigate airborne noises produced by turbochargers in passenger vehicles. The content of this book is intended for advanced undergraduates, graduates in mechanical engineering, research scientists and practicing engineers who want to better understand the interactions between these working fields and the resulting impact on the interesting topic of Aero and Vibroacoustics of Automotive Turbochargers.

  2. Automotive Stirling engine development program: A success

    Science.gov (United States)

    Tabata, W. K.

    1987-01-01

    The original 5-yr Automotive Stirling Engine Development Program has been extended to 10 years due to reduced annual funding levels. With an estimated completion date of April 1988, the technical achievements and the prospectives of meeting the original program objectives are reviewed. Various other applications of this developed Stirling engine technology are also discussed.

  3. Plastic optical fibers for automotive applications

    Science.gov (United States)

    Suganuma, Heiroku; Matsunaga, Tadayo

    1991-12-01

    High heat resistant optical fibers (POFs) have been developed for various automotive applications. Plastic chips with POF light guide have been used in place of a clearance monitor lamp. POF cords and cables have been used in the car-audio system, car-navigation system, and other data communication systems. This paper describes the structures, properties, and reliabilities of POFs for these applications.

  4. 78 FR 36633 - National Automotive Sampling System

    Science.gov (United States)

    2013-06-18

    ... complete Privacy Act statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you... 21, 2012, NHTSA published a Federal Register notice (77 FR 37471-72) soliciting comments from NASS... National Highway Traffic Safety Administration National Automotive Sampling System AGENCY: National...

  5. Automotive gear oil lubricant from soybean oil

    Science.gov (United States)

    The use of lubricants that are based on renewable materials is rapidly increasing. Vegetable oils have good lubricity, wear protection and low volatility which are desired properties for automotive gear lubricant applications. Soybean oil is used widely in the lubricant industry due to its properti...

  6. A listening test system for automotive audio

    DEFF Research Database (Denmark)

    Christensen, Flemming; Geoff, Martin; Minnaar, Pauli;

    2005-01-01

    This paper describes a system for simulating automotive audio through headphones for the purposes of conducting listening experiments in the laboratory. The system is based on binaural technology and consists of a component for reproducing the sound of the audio system itself and a component for...

  7. Metrics for Automotive Merchandising, Petroleum Marketing.

    Science.gov (United States)

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students in automotive merchandising and petroleum marketing classes, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know…

  8. Reoperations Following Cervical Disc Replacement

    OpenAIRE

    Skovrlj, Branko; Lee, Dong-Ho; Caridi, John Michael; Cho, Samuel Kang-Wook

    2015-01-01

    Cervical disc replacement (CDR) has emerged as an alternative surgical option to cervical arthrodesis. With increasing numbers of patients and longer follow-ups, complications related to the device and/or aging spine are growing, leaving us with a new challenge in the management and surgical revision of CDR. The purpose of this study is to review the current literature regarding reoperations following CDR and to discuss about the approaches and solutions for the current and future potential c...

  9. Grain charging in protoplanetary discs

    OpenAIRE

    Ilgner, Martin

    2011-01-01

    Recent work identified a growth barrier for dust coagulation that originates in the electric repulsion between colliding particles. Depending on its charge state, dust material may have the potential to control key processes towards planet formation such as MHD (magnetohydrodynamic) turbulence and grain growth which are coupled in a two-way process. We quantify the grain charging at different stages of disc evolution and differentiate between two very extreme cases: compact spherical grains a...

  10. Gravitating discs around black holes

    Czech Academy of Sciences Publication Activity Database

    Karas, Vladimír; Huré, J.-M.; Semerák, O.

    2004-01-01

    Roč. 21, č. 7 (2004), R1-R5. ISSN 0264-9381 R&D Projects: GA ČR GA205/03/0902; GA AV ČR KSK1048102 Institutional research plan: CEZ:AV0Z1003909 Keywords : black holes * accretion discs * general relativity Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 2.941, year: 2004

  11. The dispersal of protoplanetary discs

    Directory of Open Access Journals (Sweden)

    Ercolano Barbara

    2013-04-01

    Full Text Available Protoplanetary discs are a natural consequence of the star formation process and as such are ubiquitous around low-mass stars. They are fundamental to planet formation as they hold the reservoir of material from which planets form. Their evolution and final dispersal and the timescales that regulate these process are therefore of particular interest. In this contribution I will review the observational evidence for the dispersal of discs being dominated by two timescales and for the final dispersal to occur quickly and from the inside out. I will discuss the current theoretical models, including X-ray photoevaporation, showing that the latter provides a natural explanation to the observed behaviour and review supporting and contrasting evidence. I will finally introduce a new mechanism based on the interaction between planet formation and photoevaporation that may explain a particular class of transition discs with large inner holes and high accretion rates that are problematic for photoevaporation models and planet formation models alone.

  12. Optic Disc Imaging by Heidelberg Retinal Tomogram in Congenital Optic Disc Anomaly

    OpenAIRE

    Kunjam Vallam; Sekhar G

    2004-01-01

    We evaluated two cases of congenital optic disc anomaly with the Heidelberg Retinal Tomograph (HRT) that could be mistaken for glaucomatous optic disc. One was an optic disc coloboma with a visual field defect and the other had an optic disc pit without a visual field defect. HRT was abnormal only in the eye with optic disc pit with normal fields. While HRT can be a valuable adjunct to disc evaluation and follow-up, it cannot be used in isolation in the differentiation of abnormal from normal...

  13. Differential Rotation in Neutron Stars Magnetic Braking and Viscous Damping

    CERN Document Server

    Shapiro, S L

    2000-01-01

    Diffferentially rotating stars can support significantly more mass in equilibrium than nonrotating or uniformly rotating stars, according to general relativity. The remnant of a binary neutron star merger may give rise to such a ``hypermassive'' object. While such a star may be dynamically stable against gravitational collapse and bar formation, the radial stabilization due to differential rotation is likely to be temporary. Magnetic braking and viscosity combine to drive the star to uniform rotation, even if the seed magnetic field and the viscosity are small. This process inevitably leads to delayed collapse, which will be accompanied by a delayed gravitational wave burst and, possibly, a gamma-ray burst. We provide a simple, Newtonian, MHD calculation of the braking of differential rotation by magnetic fields and viscosity. The star is idealized as a differentially rotating, infinite cylinder consisting of a homogeneous, incompressible conducting gas. We solve analytically the simplest case in which the ga...

  14. Syntegra: complete integration of traction, bogie and brake systems

    Energy Technology Data Exchange (ETDEWEB)

    Loewenstein, L.; Wangelin, F. von [Siemens AG, Transportation Systems, Erlangen (Germany). Group Technology TS GT; Teichmann, M.; Hoffmann, T. [Siemens TS, Graz (Austria); Joeckel, A. [Siemens Automation and Drives, Nuernberg (Germany)

    2007-07-01

    With Syntegra {sup registered} technology, Siemens has developed an approach to the complete integration of traction, bogie and brake systems, and this has initially been put into practice for metro, underground and S-Bahn (urban regional express) trains. Syntegra constitutes a fundamentally new approach, achieving a greater intensity of integration compared with the types of drive system that have been in use up until now. With Syntegra, the bogie, transmission and brake components are all brought together as part of one and the same system. The integration and, more especially, the technological advances within the three named areas bring about numerous synergies. The new generation of powered bogie features a combination of high efficiency, low dead weight and reduced emissions. A Syntegra drive system achieves a performance which is markedly better than that of conventional systems. (orig.)

  15. Proto-planetary disc evolution and dispersal

    Science.gov (United States)

    Rosotti, Giovanni Pietro

    2015-05-01

    Planets form from gas and dust discs in orbit around young stars. The timescale for planet formation is constrained by the lifetime of these discs. The properties of the formed planetary systems depend thus on the evolution and final dispersal of the discs, which is the main topic of this thesis. Observations reveal the existence of a class of discs called "transitional", which lack dust in their inner regions. They are thought to be the last stage before the complete disc dispersal, and hence they may provide the key to understanding the mechanisms behind disc evolution. X-ray photoevaporation and planet formation have been studied as possible physical mechanisms responsible for the final dispersal of discs. However up to now, these two phenomena have been studied separately, neglecting any possible feedback or interaction. In this thesis we have investigated what is the interplay between these two processes. We show that the presence of a giant planet in a photo-evaporating disc can significantly shorten its lifetime, by cutting the inner regions from the mass reservoir in the exterior of the disc. This mechanism produces transition discs that for a given mass accretion rate have larger holes than in models considering only X-ray photo-evaporation, constituting a possible route to the formation of accreting transition discs with large holes. These discs are found in observations and still constitute a puzzle for the theory. Inclusion of the phenomenon called "thermal sweeping", a violent instability that can destroy a whole disc in as little as 10 4 years, shows that the outer disc left can be very short-lived (depending on the X-ray luminosity of the star), possibly explaining why very few non accreting transition discs are observed. However the mechanism does not seem to be efficient enough to reconcile with observations. In this thesis we also show that X-ray photo-evaporation naturally explains the observed correlation between stellar masses and accretion

  16. Magnetic Braking and Protostellar Disk Formation: The Ideal MHD Limit

    Science.gov (United States)

    Mellon, Richard R.; Li, Zhi-Yun

    2008-07-01

    Magnetic fields are usually considered dynamically important in star formation when the dimensionless mass-to-flux ratio is close to, or less than, unity (λ lesssim 1). We show that, in disk formation, the requirement is far less stringent. This conclusion is drawn from a set of 2D (axisymmetric) simulations of the collapse of rotating, singular isothermal cores magnetized to different degrees. We find that a weak field corresponding to λ ~ 100 can begin to disrupt the rotationally supported disk through magnetic braking, by creating regions of rapid, supersonic collapse in the disk. These regions are separated by one or more centrifugal barriers, where the rapid infall is temporarily halted. The number of centrifugal barriers increases with the mass-to-flux ratio λ. When λ gtrsim 100, they merge together to form a more or less contiguous, rotationally supported disk. Even though the magnetic field in such a case is extremely weak on the scale of dense cores, it is amplified by collapse and differential rotation, to the extent that its pressure dominates the thermal pressure in both the disk and its surrounding region. For relatively strongly magnetized cores with λ lesssim 10, the disk formation is suppressed completely, as found previously. A new feature is that the mass accretion is highly episodic, due to reconnection of the magnetic field lines accumulated near the center. For rotationally supported disks to appear during the protostellar mass accretion phase of star formation in dense cores with realistic field strengths, the powerful magnetic brake must be weakened, perhaps through nonideal MHD effects. Another possibility is to remove, through protostellar winds, the material that acts to brake the disk rotation. We discuss the possibility of observing a generic product of the magnetic braking, an extended circumstellar region that is supported by a combination of toroidal magnetic field and rotation—a "magnetogyrosphere"—interferometrically.

  17. Subway Train Braking System: A Fuzzy Based Hardware Approach

    Directory of Open Access Journals (Sweden)

    Mamun B.I. Reaz

    2011-01-01

    Full Text Available Problem statement: Automated subway train-braking system require perfection, efficiency and fast response. In order to cope with this concerns, an appropriate algorithm need to be developed which need to be implemented in hardware for faster response. Approach: In this research, the FPGA realization of fuzzy based subway train braking system has been presented on an Alter FLEX10K device to provide an accurate and increased speed of convergence of the network. The fuzzy based subway train braking system is comprised of fusilier, inference, rule selector and defuzzifier modules. Sixteen rules are identified for the rule selector module. After determining the membership functions and its fuzzy variables, the Max-Min Composition method and Madman-Min implication operator are used for the inference module and the Centre of Gravity method is used for the defuzzification module. Each module is modeled individually using behavioral VHDL. The layers are then connected using structural VHDL. Two 8-bit and one 8-bit unsigned digital signals are used for input and output respectively. Six ROMs are defined in order to decrease the chances of processing and increasing the throughput of the system. Results: Functional simulations were commenced to verify the functionality of the individual modules and the system as well. We have validated the hardware implementation of the proposed approach through comparison, verification and analysis. The design has utilized 2372 units of LC with a system frequency of 139.8MHz. Conclusion: In this research, the FPGA realization of fuzzy brake system of subway train has been successfully implemented with minimum usage of logic cells. The validation study with C model shows that the hardware model is appropriate and the hardware approach shows faster and accurate response with full automatic control.

  18. Differential Rotation in Neutron Stars: Magnetic Braking and Viscous Damping

    OpenAIRE

    Shapiro, Stuart L.

    2000-01-01

    Diffferentially rotating stars can support significantly more mass in equilibrium than nonrotating or uniformly rotating stars, according to general relativity. The remnant of a binary neutron star merger may give rise to such a ``hypermassive'' object. While such a star may be dynamically stable against gravitational collapse and bar formation, the radial stabilization due to differential rotation is likely to be temporary. Magnetic braking and viscosity combine to drive the star to uniform ...

  19. Carbon nanotube torsional springs for regenerative braking systems

    Science.gov (United States)

    Liu, Sanwei; Martin, Corbin; Lashmore, David; Schauer, Mark; Livermore, Carol

    2015-10-01

    The modeling and demonstration of large stroke, high energy density and high power density torsional springs based on carbon nanotube (CNT) yarns is reported, as well as their application as energy-storing actuators for regenerative braking systems. An originally untwisted CNT yarn is cyclically loaded and unloaded in torsion, with the maximum rotation angle increasing incrementally until failure. The measured average extractable energy density values are 2.9 kJ kg-1  ±  1.2 kJ kg-1 and 3.4 kJ kg-1  ±  0.4 kJ kg-1 for 1-ply CNT yarns and 2-ply CNT yarns, respectively. Additionally, a regenerative braking system is demonstrated to capture the kinetic energy of a wheel and store it as elastic energy in twisted CNT yarns. When the yarn’s twist is released, the stored energy reaccelerates the wheel. The measured energy and mean power densities of the CNT yarns in the simple regenerative braking setup are on average 3.3 kJ kg-1 and 0.67 kW kg-1, respectively, with maximum measured values of up to 4.7 kJ kg-1 and 1.2 kW kg-1, respectively. A slightly lower energy density of up to 1.2 kJ kg-1 and a 0.29 kW kg-1 mean power density are measured for CNT yarns in a more complex setup that mimics a unidirectional rotating regenerative braking mechanism.

  20. Neural Signatures Enhance Emergency Braking Intention Detection during Simulated Driving

    OpenAIRE

    Stefan Haufe; M. F. Gugler; Sagebaum, M.

    2010-01-01

    In many safety-critical areas such as individual car traffic, human performance has become the limiting factor. Modern driving assistance systems can detect potential upcoming crashes and take preparatory measures or even initiate automatic emergency braking.We conducted a driving simulator study (N=20) using a customized version of the open-source racing software TORCS. The experiment comprised 3 blocks (45 minutes each) of driving, in which the subjects had to tightly follow a computer-cont...