Brake System

Günümüzde sürüş güvenliği çoğunlukla araç teknolojileri ve sürücü eğitimi üzerine kuruludur. Ancak araç kullanımı sırasında insan vücudunun sinir sistemi, refleks yönetimi ve kas yorgunluğu gibi etkenler göz ardı edilmektedir. Bu çalışma, hız seviyelerine göre el kullanımı ve direksiyon kontrolünün yeniden yapılandırılmasını öngören bir sürüş modeli önermektedir. Model, özellikle panik anlarında nörolojik görev dağılımı ile kontrolün daha verimli korunabileceğini savunur.

The aim of this research is to investigate the ability of manufacturing and testing a new mechanism for wedge disc brake. The new mechanism consists mainly of the wedge itself, which is controlled by a gear set to change its inclination angle. The wedge is sliding on a surface controlling its inclination angle. The control of the inclination angle can change the factor between the applied force from the brake pressure source and the normal force to the brake pads. Changing the normal force to the brake pads can change the brake force on the rotor disc. The brake force from the pads on the rotor disc is the main goal in this research. The goal is to increase this force by increasing the normal force on the brake pads. The new mechanism was manufactured and tested experimentally in the laboratory by the use of a lathe machine carrying the mechanism for investigation. The results showed the ability of the new mechanism to increase the brake force by about seven times than conventional disc brake. The tested inclination angles were 45 o , 35 o , 25 o , 15 o , 12 o , and 10 o with different rotational speeds of 76, 150, 230, 305 rpm at different applied hydraulic pressure of 5, 7.5, 10, 12.5 bar. In all mentioned cases, the inclination angle of 12o was found to be the best angle in increasing the brake force.

The performance of the disc brake system basically depends on geometric parameters and operating parameters. The aim of this research is to optimise the operating parameters of the disc brake system to improve the performance, durability and robustness of the brake system. Operating parameters such as braking pressure, rotational speed and load with four levels each are considered as input parameters and braking time as a response parameter. A standard design of experiments (DOE) by Taguchi method is applied to evaluate the main and interactive effect on the performance. The S-N ratio graph describes the significant effect of each parameter on the brake performance and suggests its optimal level for better performance. Multiple linear regression equation describes the satisfactory correlation between the experimental and computed values which proves the realism of the results.

High-quality, asbestos-free brake pads were made in this study using basic materials that were purchased locally. The Toyota Corrolla 2006 modeldisc brake friction lining were made with powdered shell of African olive (Canariumschweinfurthii)and Udara nut (Chrysophyllumcainito) as the main material, polyester resin as the binder material, graphite as the lubricant, and metal chips and carbides as the abrasives. The commercial brake pad purchased (Toyota Corrolla 2006 model) was used for the comparison. By altering the mass composition of the shell of African olive and Udara nuts,three distinct samples were obtained. The masses of the shell of African olive and Udara nutsare equal in Sample A. Sample C has a larger mass of Udara nut (69.23%) and a lower mass of African olive (30.77%), whereas Sample B has a higher mass of African olive (73.08%) and a lower mass of Udara nut (26.92%). For every sample, a fixed pressure of 16.75 kN/m 2 and particle size of 0.63µm were employed. The composition of the lubricant, abrasive, and binder remained consistent. According to the test results, samples A, B, and C had static and dynamic coefficients of friction of 0.

The wear of component is regularly a serious issue prompting the product provision period. Wear prophecy is consequently a vital area in technology. The wear recreation method with profitable software ANSYS 10.0 finite element (FE) was implemented with the linear wear Archard equation. The wear of commercially available brake pad sliding against Ti-6Al-4V disc was analyzed with FEM under different operating conditions such as normal load, sliding velocity, sliding distance and operating temperature. A 3D-8 node structural element (SOLID 185) and 3D-8 node surface-to-surface contact elements (Target 170 and Contact 174) is used to analyze the wear of pin and disc. Using ideal boundary conditions, the simulation predicts the wear rate, wear depth, contact pressure and contact friction stresses under different operating conditions at the contact zone.

The contributions of various non-linearities to an automotive drum brake’s transient response has been studied analytically. A discrete system model with friction, contact, and kinematic non-linearities is formulated such
that each of the non-linearities could be linearized independently. The contact between the brake shoes and the brake drum is modeled using Hertzian contact theory, supported by kinematic relationships derived using vector geometry for a given design. Several variants of quasi-linear models are derived from the non-linear system by linearizing individual non-linearities. Transient responses of these models were obtained numerically during a typical braking event, consisting of the impacting phase and contact phase. The linearized and nonlinear responses are compared based on the time-histories, spectra, and spectrograms. The self-energizing and de-energizing effects of the brake shoes on the dynamic behavior of the system were quantified. Finally, the
trends from the developed non-linear model were qualitatively and quantitatively correlated with published data.

A non-contact method, using magnetic drag force principle, was proposed to design the braking systems to improve the shortcomings of the conventional braking systems. The extensive literature detailing all aspects of the magnetic braking is briefly reviewed, however little of this refers specifically to upright magnetic braking system, which is useful for industries. One of the major issues to design upright magnetic system is to find out the magnetic flux. The changing magnetic flux induces eddy currents in the conductor. These currents dissipate energy in the conductor and generate drag force to slow down the motion. Therefore, a finite element model is developed to analyze the phenomena of magnetic flux density when air gap and materials of track are varied. The verification shows the predicted magnetic flux is within acceptable range with the measured value. The results will facilitate the design of magnetic braking systems. Keyword: Friction, Heat, Conventional Braking, and Ele...

The main objective of this paper is to clarify the type of braking system to be used as primary and secondary brakes. This paper is about design and evaluation of braking system for an electric car, we have emphasized on various aspects which are required for the design and evaluation of system such as theoretical study, analytical calculations, trials on the system and comparison of analytical calculations and actual performance

Tato bakalářská práce se zabývá konstrukčním návrhem sloupového jeřábu, včetně důležitých pevnostních výpočtů. Tato práce dále obsahuje výběr vhodného kladkostroje a výkresovou dokumentaci v podobě sestavy jeřábu a výkresu sloupu.This bachelor thesis deals with the structural design of the column crane, including important strength calculations. This thesis also includes a selection of a suitable hoist and drawing documentation in the form of a crane assembly and a pole drawing.

A B S T R A C T The introduction of the paper gives the basic concepts, historical development of methods of Fault Tree Analysis -FTA and Failure Modes, Effects and Criticality Analysis -FMECA for analysis of the reliability and safety of technical systems and importance of applying this method is highlighted. Failure analysis is particularly important for systems whose failures lead to the endangerment of people safety, such as, for example, the braking system of motor vehicles. For the failure analysis of the considered device, it is necessary to know the structure, functioning, working conditions and all factors that have a greater or less influence on its reliability. By formation of the fault tree of drum brakes in braking systems of commercial vehicles, it was established a causal relation between the different events that lead to a reduction in performance or complete failure of the braking system. Based on data from exploitation, using FMECA methods, determination of the cri...

В статье приведена математическая модель прямолинейного движения карьерного автосамосвала, как многомассовой системы с пятью степенями свободы на прямолинейном участке дороги с учетом состояния дорожного покрытия. Современное состояние карьерного автомобильного транспорта. Значительные финансовые затраты, связанные с транспортированием горных пород для обеспечения технологического процесса добычи полезных ископаемых открытым способом, обусловливают постоянное ведение широкомасштабных работ по техническому совершенствованию средств карьерного автомобильного транспорта. Их конструкция должна максимально учитывать особенности работы в карьерах: стесненные условия движения, короткие расстояния транспортирования, затяжные подъемы и спуски. Значительный вклад в развитие теории и практики использования автомобильного транспорта на открытых горных разработках внесли М.В. Васильев, А.А. Кулешов, А.Н. Казарез, Н.В. Мельников, М.Г. Потапов, В.В.Ржевский, В.П. Смирнов, И.М. Циперфин, В.Д. Штейн, Б.Я. Яковенко, Зырянов И.В., Бунякин А.В., Смирнов Г.А. [1,2,3] и др. Ими были созданы математические модели для исследования динамических процессов карьерного автомобильного транспорта, учитывающие особенности эксплуатации (в частности неровности дороги, удар при экскаваторной загрузке). Составленные при этом уравнения движения представляют собой систему нелинейных дифференциальных уравнений, которые решаются при заданных начальных условиях в определенном промежутке интегрирования с использованием специально разработанного алгоритма итерационно-разностного типа с определением точек разрыва правых частей [1, 2, 3,] . Дальнейшие усовершенствования конструкций автосамосвалов, которые работают в особо сложных условиях, и оценка их работоспособности, требуют привлечения при составлении расчетной схемы большего числа конструктивных и технологических факторов, что позволяет определить их влияние на эксплуатационные характеристики машины и её надежность. Поэтому, исследование динамики машины и получение амплитудно-частотных характеристик в зависимости от физико-механических свойств упругих связей и масс отдельных частей машины является актуальной задачей. Исследуя динамику автомобиля как сложную многомассовую систему, необходимо учитывать, что при различных режимах движения влияние механических характеристик отдельных элементов машины проявляется в разной степени. Проведем исследование динамики прямолинейного движения машины без учета бокового уклона дороги. Цель исследования -составление расчетной схемы и уравнений движения при прямолинейном движении машины с учетом характеристик ее упругих связей и профиля дороги. Составление расчетной схемы и уравнения движения. При составлении расчетной схемы автомобиля допускаем, что механические характеристики колес, расположенных на одной оси соответствующих мостов -одинаковы. В этом случае автосамосвал можно представить в виде системы тел (рис. 1), соединенных между собой упругими и неупругими связями, причем функции, описывающие взаимодействие колес автомобиля с дорогой, моделируют различные условия движения.

Brakes are the most important components of any automobile. Brakes provides the ability to reduce or bring
automobile to a complete stop. Process of braking is usually achieved by applying pressure to the brake disc. The
main objective of this project is to perform an appropriate design and suitable brake rotor to enhance the
performance of high speed heavy vehicle. The design of the brake disc is modelled using the SOLID WORKS.
From the design and material change, by changing the material it results it can be concluded that grey cast iron
has performed better as compared to stainless steel as this material as anti-fade properties which improves the life
of the brake rotor. Then by using the 3D printing technology we are preparing the prototype of the disc plate in
the FORGE CREATOR PRO 3D printing software.

In a vehicle, the most capable sistems to avoid acidentes are brake and steering. Specially the the brake sistem, that has the extremly important task of deccelerating the vehicle in a safe and eficiente way, despite the surrounding conditions. Thus, this work will approach a design methodology of a Baja SAE brake sistem, wich is a Vehicle built by college students from many universities who have in mind a competition, on wich the designs will be judged and ranked. For such vehicles, beyond the driver´s and  vehicle’s structure safety, there is one more concerning in the case the brake sistem doesn’t work correctly, this concerning is the disqualification of the team from the competition. To build a solid and reliable methodology, in this job i will talk about the differents kinds of brake sistems availables on the market and their basic components, also was made a recomendation about the best combination of triggering method and the triggered assembly, so, this methodology was built considering a hydraulic system with disc-calliper assembly at the wheels. At first, the vehicle behavior during the braking was explained by doing an analisys of the longitudinal vehicle dynamics, further was shown how to calculate the braking power of the system by calculating the braking torque and braking forces that it is able to generate. This writing was built for the engeneering students, specially the ones who participate on a Baja team and are responsibles by the brake design of it’s team, and with a main goal to enlight and provide a guide on how to choose your componentes and design your system. When puted to test at the regional competition SAE Northeast 2020, the showed methodology came out to be satisfactory by receiving the third place on the design presentation.  Keywords: braking; Baja; design. 

Em um veículo, os sistemas mais capazes de evitar acidentes são o de freio e o de direção. Especialmente o primeiro, que tem uma função importantíssima de desacelerar o veículo de forma segura e eficiente independentemente das condições do ambiente. Pensando nisso, esse trabalho abordará uma metodologia a ser seguida para o projeto de um sistema de frenagem de um veículo Baja SAE, que é um veículo construído por estudantes de várias universidades com o foco em participar de uma competição, na qual os projetos serão julgados e ranqueados. Para esses veículos, além da segurança do piloto e da estrutura do veículo, há uma preocupação extra se o sistema de frenagem não for eficiente, já que a equipe poderá ser, assim, desclassificada da competição. Para construir uma metodologia robusta e confiável, no presente trabalho foram expressos os diferentes tipos de sistema de frenagem disponíveis no mercado e seus componentes básicos. Além disso, foi sugerida uma melhor combinação de modo de acionamento e conjunto acionador, então essa metodologia foi proposta considerando um sistema de acionamento hidráulico com conjuntos pinças-discos nas rodas. Primeiro, foi explicado o comportamento do veículo durante a frenagem por meio da explanação do assunto da dinâmica veicular longitudinal, segundo foi mostrado como é calculado o poder de frenagem do sistema ao calcular o torque e a força de frenagem que ele consegue exercer. O trabalho foi escrito visando, principalmente, os estudantes de engenharia participantes de uma equipe Baja e responsáveis pelo projeto dos freios da sua equipe, com o intuito de esclarecer e dar um guia sobre como realizar as escolhas dos componentes e como fazer o projeto do seu sistema. Quando colocado à prova na competição regional SAE Nordeste 2020, a metodologia apresentada se mostrou satisfatória ao receber a terceira colocação na apresentação de projetos de frenagem.  Palavras-chave: frenagem; Baja; dimensionamento.

A detailed model for pneumatic S-cam drum brake systems is developed and integrated into a multibody dynamic model for a 33-ft A-double long combination vehicle (LCV). The model, developed in TruckSim®, is used to study the dynamics of LCVs during straight-line braking at various speeds. It includes the response delay in braking that occurs from the time of application to when the brakes are applied at the drum for all axles. Additionally, the model incorporates an accurate characterization of brake torque versus chamber pressure at different speeds, along with the anti-lock brake system (ABS) dynamics, to yield an accurate prediction of the vehicle's deceleration during braking. The modeling results are compared with test results at speeds ranging from 20 to 65 mph on dry pavement. A close match between the model's prediction and test results is observed. The model is then used to perform a parametric study that evaluates braking distance and time for different pavement coefficients of friction (p) at various speeds. The results indicate a distinct nonlinear relationship between p and braking dynamics. At various p, stopping time increases linearly with speed, as perhaps expected. Stopping distance, however, increases nonlinearly for larger p and linearly for smaller p versus speed. At a given speed, stopping time increases nonlinearly with reduced p, whereas stopping distance increases relatively linearly with reduced p.

Sistem handbrake saat ini adalah sistem handbrake yang ditarik tangan dan pakai tombol, handbrake bisasanya dipakai untuk mengatasi medan jalan yang menanjak. Acapkali si pengemudi gugup ketika didapati tenaga kendaaran tidak cukup kuat untuk melakukan tanjakan tersebut sehingga mesin mobil mati. Selain hal tersebut pada jalan menurun si pengemudi juga lupa mengaktifkan handbrake ketika turun dari kendaraan. Pada penelitian ini merancang sebuah handbrake mobil yang dapat aktif pada saat kontak mati dan handbrake mati pada saat kendaraan tersebut kontak di nyalakan dan memberikan tombol darurat untuk melepas handbrake jika terjadi konsleting pada kontak atau control CHG/charging sistem (indikator accu). Sehingga membantu pengendara untuk keamanan berkendara yang lebih aman. Ada beberapa tahapan yang dilakukan antara lain: memilih dan menetapkan platform kendaraan yang akan dikonversi menjadi kendaraan dengan handbrake otomatis, memilih motor sebagai penarik kawat seling pada drum rem...

Safety aspect in automotive engineering has been considered as a number one priority in development of new vehicle. Brakes convert friction to heat, but if the brakes get too hot, they will cease to work because they cannot dissipate enough heat. Ventilated disc brake is the state of the art technology in automobile brake system .In this study FEA approach has been conducted in order to identify the temperature distributions and behavior of disc brake rotor in transient state. This paper reviews work of previous investigators on transient thermal analysis on the vented disk rotor and rotor designs to evaluate and compare their performance. Time varying temperature load is applied on the rotors and the temperature distribution was analyzed considering cooling parameters (convection and radiation). The main of aim of this review work is to study various researches done in past to improve heat transfer rate of disc brake (ventilated) by changing vane geometry and material.

Of the various countermeasures used to address disc brake squeal noise, noise shims have proven to be very effective in addressing medium to high frequency squeal related to rotor bending vibration. However, for squeal noise at low frequency and squeal related to rotor in-plane vibration, noise shims are less effective. Recently, there is more and more evidence showing that many field claims of brake squeal noises are related to the brake rotor's in-plane vibration modes. So it becomes necessary to review brake design for suppression of high frequency brake squeal noise.

Of the various countermeasures used to address disc brake squeal noise, noise shims have proven to be very effective in addressing medium to high frequency squeal related to rotor bending vibration. However, for squeal noise at low frequency and squeal related to rotor in-plane vibration, noise shims are less effective. Recently, there is more and more evidence showing that many field claims of brake squeal noises are related to the brake rotor's in-plane vibration modes. So it becomes necessary to review brake design for suppression of high frequency brake squeal noise.

This paper is devoted to discussion of the efficiency of reduced models based on a Double Modal Synthesis method that combines a classical modal reduction and a condensation at the frictional interfaces by computing a reduced complex mode basis, for the prediction of squeal noise of mechanical systems subjected to friction-induced vibration. More specifically, the use of the multiresolution signal decomposition of acoustic radiation and wavelet representation will be proposed to analyze details of a pattern on different observation scales ranging from the pixel to the size of the complete acoustic pattern. Based on this approach and the definition of specific resulting criteria, it is possible to quantify the differences in the representation of the acoustic fields for different reduced models and thus to perform convergence studies for different scales of representation in order to evaluate the potential of reduced models. The effectiveness of the proposed approach is tested on the...

Particulate reinforced aluminum matrix composites are attractive materials due to their strength, ductility, toughness. This study presents the result of an experimental investigation on the mechanical and wear properties of aluminum alloys 6061 MMC reinforced with glass particulate of 40 microns where dispersed in aluminum matrices at 2, 4, 6 and 8 wt%. Therefore judicious selection of the variables is important to optimize the properties of composites. The shape, size, volume fraction and orientation of reinforcement particles and matrix compositions have to be carefully chosen. The composite prepared by stir casting method the stir casted specimen wear tested for the mechanical and wear properties. The aluminum matrix is strengthening when it is reinforced with hard ceramic phases. In this work the effect of Glass particulate in aluminum matrix on the mechanical and wear properties of the composites is investigated the mechanical properties of composite materials are strongly dependent on micro structural parameters of the system the investigation relives that the significant improvement in the mechanical and wear properties of the composites.

A non-contact method, using magnetic drag force principle, was proposed to design the braking systems to improve the shortcomings of the conventional braking systems. The extensive literature detailing all aspects of the magnetic braking is briefly reviewed, however little of this refers specifically to upright magnetic braking system, which is useful for industries. One of the major issues to design upright magnetic system is to find out the magnetic flux. The changing magnetic flux induces eddy currents in the conductor. These currents dissipate energy in the conductor and generate drag force to slow down the motion. Therefore, a finite element model is developed to analyze the phenomena of magnetic flux density when air gap and materials of track are varied. The verification shows the predicted magnetic flux is within acceptable range with the measured value. The results will facilitate the design of magnetic braking systems. Keyword: Friction, Heat, Conventional Braking, and Ele...

Bu calismada tasitlarin farkli yol sartlarindaki fren‐suspansiyon testlerinin laboratuvar ortaminda yapilmasini saglayacak bir tasit test cihazi tasarlanip imal edilmistir. Literaturde tasit testleri konusunda onemli calismalarin bulundugu ancak ozellikle yol testlerinin maliyetinin yuksek olmasi ve deney sonuclarinda olusacak sapmanin buyuklugu goz onune alindiginda istenilen hassasiyetin elde edilemedigi gorulmektedir. Tasarlanan fren‐suspansiyon test cihazi ile yol sartlari laboratuvar ortaminda olusturularak standart testlerin daha hassas bir sekilde yapilmasi saglanmistir. Tasarim ve Imalat islemleri gerceklestirilen test cihazinin optimizasyon testleri yapilmistir.

Anti-Lock Braking Systems (ABS) and Brake-by-Wire Systems (BBW) are safety-critical applications by nature. Such systems are required to demonstrate high degrees of dependability. Fault-tolerance is the primary means to achieve dependability at runtime and has been an active research area for decades. Fault-tolerance is usually achieved in traditional embedded computing systems through redundancy and voting methods. In such systems, hardware units, actuators, sensors, and communication networks are replicated where special voters vote against faulty units. In addition to traditional hardware and software redundancy, hybrid and reconfiguration-based approaches to fault-tolerance are evolving. In this article, we present a reconfiguration-based fault-tolerant approach to achieve high dependability in ABS BBW braking systems. The proposed architecture makes use of other components of less safety-critical systems to maintain high dependability in the more safety-critical systems. This i...

We would like to throw some light on the New and Innovative concept which is known as "Mobile Garbage Cleaner". Mobile Garbage Cleaner is a new concept that is fully examined theoretically successfully. In world, waste production has doubled over the past 20 years. By 2050, the world may produce huge garbage at an alarming rate of 5 billion tons per year. Poor waste management in many developing or under developed countries is a threat to humanity& ecosystem. We propose a community sourced, data-driven, sustainable & economic solution to the garbage problem. In this theoretical analysis, we have found the effective way to make our nation, "A Clean Hindustan "in association with "Swachch Bharat Abhiyan". The system integrates the mechanism to uplift the garbage on roadside anywhere in cities or any other areas with the help of Vacuum Pressure & shifting it to incineration chamber will burn the garbage to ashes instantly making the surroundings clean & ri...

Introduction Since the beginning of the space age, parachute-based recovery systems have often been used to recover space cargo. In this case, two-stage parachute systems are usually used to recover a space cargo. Due to the high initial speed of the cargo when it enters the atmosphere, a high-speed parachute stage is used to reduce the speed of the cargo and make it stable. The so-called first-stage parachute is called a brake chute. Brake chutes are usually of balut, ribbon, and ring slot types, which are selected and designed according to the cargo speed, altitude, weight, and atmospheric conditions. Braking parachutes have more porosity than textile parachutes. The higher the porosity of a parachute, the lower the drag coefficient and opening force, but the higher its stability. This is the reason for using brake parachutes as the first stage of space cargo recovery. After reducing the speed of the cargo and stabilizing it with the braking parachute, the main textile parachutes are used as the second step of recovery and lead to a gentle landing of the cargo on the ground. One of the methods of studying parachutes is to perform flight tests. In these tests, the cargo and parachute assembly are tested by a rocket or aircraft. Flight tests are the most accurate method of evaluating the performance of parachutes and are the most consistent with realistic conditions. However, these tests are expensive and cannot obtain all the required parameters, such as canopy pressure distribution. In addition to flight testing, other methods, including truck towing and wind tunnel testing are also common for evaluating parachute performance. The truck towing test is performed by restrained movement (towing) of the parachute by a vehicle, such as an airplane, missile, truck, van, or boat. Truck towing test has some advantages, including relatively easy control of test conditions, accurate performance measurement, reusability of test vehicles, ease of repeated testing, and low cost. On the other hand, this method has some disadvantages, namely the impossibility of testing for high speeds, limitation in the distance of the parachute from the vehicle, measurement errors due to diverse factors (e.g.,

In recent years, the use of lightweight materials with improved mechanical and tribological qualities has significantly advanced. This study aims to develop an aluminum 2024 matrix alloy reinforced with 0, 3, 6, 9, and 12 weight percent of Al 2 O 3 using the stir casting technique. The alloy was melted at approximately 700°C, mixed with preheated Al 2 O 3 particles, and cast into a sand mold with various end chills, including graphite, mild steel, copper, brass, and cast iron, to facilitat e directional solidification. Mechanical testing revealed that the copper-chilled MMC achieved the highest hardness and strength at reinforcement levels of 9% and 12% by weight, respectively, with increases of 9.88% in strength and 16.66% in hardness compared to the base alloy. Micro structural examination showed uniform dispersion of nano alumina particles, contributing to improved wear resistance. The copper-chilled MMC exhibited high friction and modest wear at lower stresses but significant wear under higher loads. The incorporation of Al 2 O 3 nanoparticles and the chilling effect enhanced the mechanical and tribological properties, resulting in a finer microstructure and better bonding between the reinforcement and matrix.

The principle of braking in road vehicles involves the conversion of kinetic energy into heat. This high energy conversion therefore demands an appropriate rate of heat dissipation if a reasonable temperature and performance stability are to be maintained. While the design, construction, and location features severely limit the heat dissipation function of the friction brake, electromagnetic brakes work in a relatively cool condition and avoid problems that friction brakes face by using a totally different working principle and installation location. By using the electromagnetic brake as supplementary retardation equipment, the friction brakes can be used less frequently and therefore practically never reach high temperatures. The brake linings thus have a longer life span, and the potential brake fade problem can be avoided. It is apparent that the electromagnetic brake is an essential complement to the safe braking of heavy vehicles. In this thesis, a new mathematical model for el...

The aim of this research is to investigate the ability of manufacturing and testing a new mechanism for wedge disc brake. The new mechanism consists mainly of the wedge itself, which is controlled by a gear set to change its inclination angle. The wedge is sliding on a surface controlling its inclination angle. The control of the inclination angle can change the factor between the applied force from the brake pressure source and the normal force to the brake pads. Changing the normal force to the brake pads can change the brake force on the rotor disc. The brake force from the pads on the rotor disc is the main goal in this research. The goal is to increase this force by increasing the normal force on the brake pads. The new mechanism was manufactured and tested experimentally in the laboratory by the use of a lathe machine carrying the mechanism for investigation. The results showed the ability of the new mechanism to increase the brake force by about seven times than conventional disc brake.

Prosthetic limbs serve as indispensable tools in restoring mobility and enhancing the quality of life for individuals with limb loss. This project focuses on the modeling and analysis of prosthetic legs, aiming to optimize their design for improved functionality and comfort. The study begins with an exploration of the significance of prostheses in enhancing the mobility and independence of amputees. Utilizing Solid Works for modeling and ANSYS for analysis, the project investigates the performance of prosthetic legs constructed from four distinct materials: Aluminum Alloy, Titanium Alloy, Carbon Fibre, and Structural Steel. These materials are selected based on their mechanical properties and suitability for prosthetic applications. The design and analysis stages involve simulating various activities that mimic the typical movements and stresses encountered during daily l ife, including walking and engaging in other essential tasks. By subjecting the prosthetic leg models to rigorous testing, the project evaluates their durability, strength, and overall performance under realistic conditions. The outcomes of this research provide valuable insights into the comparative advantages and limitations of different materials in prosthetic leg design. Additional ly, it offers recommendations for optimizing prosthetic limb design to better meet the diverse needs and preferences of users. Ultimately, this work contributes to advancing the field of prosthetic engineering, paving the way for the development of mor e efficient and user-friendly prosthetic solutions.

В статье разработана методика оценки термонагруженности тормозных механизмов в горных условиях эксплуатации. Из приведённых расчётов следует, что при работе в горных условиях тормозные механизмы автомобиля нагреваются неравномерно из-за высокой термонагруженности тормозов задней оси, что влияет на безопасную эксплуатацию в горных условиях. Это подтверждается зависимостью тормозного пути автомобиля от температуры накладок задних тормозных механизмов, полученной экспериментальным путём.

INFLUENCE OF THERMAL LOADING OF BRAKE MECHANISMS ON THE EFFICIENCY OF BRAKING A CAR IN MINING CONDITIONS OF OPERATION

The article developed a methodology for assessing the thermal load of brake mechanisms in mountainous operating conditions. From the above calculations, it follows that when working in mountainous conditions, the brakes of the car heat up unevenly due to the high thermal load on the rear axle brakes, which affects the safe operation in mountainous conditions. This is confirmed by the dependence of the vehicle braking distance on the temperature of the rear brake linings, obtained experimentally.

Most researchers characterize brake squeal as a vibration of the brake rotor that produces an irritating noise to automobile passengers. Recently, the concept of dither control was successfully used to suppress the resonant vibration of components of a brake system, thereby eliminating its acoustic disturbance. Dither control is a high frequency periodic disturbance signal introduced into a brake system to quench friction-induced oscillations. This paper presents results of the measurement of dynamic forces transmitted to the inboard pad of a floating caliper brake system during suppression of squeal using dither control. A stack of piezoelectric elements was placed inside the brake piston to induce a high frequency displacement to the inboard pad. A 20 kHz voltage was applied over the piezoelectric stack to dither the brake's normal clamping force. Measurements of the dynamic force transmitted to the brake pad were made with a load cell that was placed in line with the stack inside the caliper. The dynamic force was measured during squeal and during its control. Squeal suppression through dither control typically required the application of a 200 Newton modulation to the static normal force.

Air Conditioning (AC) is the one of system in aircraft to make a passanger and all cabin crew comfortable. Trim Air Pressure Regulating and Shutoff Valve or also known as Trim Air PRSOV is a component on the Boeing 737-800 aircraft to regulate flow of hot air constantly before entering the aircraft cabin. Refering to the data for the last 6 years, the replacement of the component belonging to one of the Indonesian national flight carrier using Boeing 737-800 aircraft was the occurance of 84 times the cooling system failure which caused the light indiacator in the cockpit to light up. Among them happened 70 times unscheduled maintenance and 14 times scheduled maintenance. Thus, this essay was made to analyze the causes of the damage that occurred to the Trim Air PRSOV. The method used in this research is Failure Mode and Effect Analysis (FMEA) is the technique used to find, identify and eliminate failures or damage to a system or process. The first step is to analyze using a Pareto d...

This paper presents the experimental study of vibration generated by friction materials of an automotive disc brake system using brake test rig. Effects of silica sand particles which are available on the road surface as an environmental condition with a size varied from 150 μm to 600 μm are evaluated. Also, the vibration of the brake disc is examined against the friction material in humidity environment conditions under variable rotational speed. The experimental results showed that the silica sand particles have significant contribution on the value of vibration amplitude which enhances with increasing the size of silica sand particles at different speed conditions. Also, it is noticed that the friction material is sensitive to humidity and the vibration magnitude increases under wet testing conditions. Moreover, it can be reported that with increasing the applied pressure and rotational speed of the braking system, the vibration amplitudes decrease for all cases.

The aim of this research is to investigate the ability of manufacturing and testing a new mechanism for wedge disc brake. The new mechanism consists mainly of the wedge itself, which is controlled by a gear set to change its inclination angle. The wedge is sliding on a surface controlling its inclination angle. The control of the inclination angle can change the factor between the applied force from the brake pressure source and the normal force to the brake pads. Changing the normal force to the brake pads can change the brake force on the rotor disc. The brake force from the pads on the rotor disc is the main goal in this research. The goal is to increase this force by increasing the normal force on the brake pads. The new mechanism was manufactured and tested experimentally in the laboratory by the use of a lathe machine carrying the mechanism for investigation. The results showed the ability of the new mechanism to increase the brake force by about seven times than conventional disc brake.

This article is a case study of Box-Behnken design application for development and evaluation a new empirical model to predict the performance of wedge disc brake. Box-Behnken design is used to study the applied pressure, rotational speed, wedge inclination angle and quantity of water spraying. A total of 27 experimental tests are conducted using brake dynamometer to estimate the main and interaction effect of these parameters. The results of analysis of variance for the braking forces from the input parameters are obtained to evaluate the goodness of the developed empirical model through F-and P-values. It is found that a strong correlation between the empirical regression model and the actual results. Moreover, in order to confirm the validity of the empirical model, additional 16 experimental tests are carried out using Taguchi method. The results showed a good agreement between the predicted empirical model and experimental results. This indicates that the developed empirical model based on operating parameters can be used successfully to predict the wedge disc brake performance.

We suggest a mathematical interpretation of the influence of the main alloy elements over the mechanical characteristics (the hardness on the crust of the rolls) of this nodular irons, resulting the average values and average square aberration of the variables HB, and the main alloying elements (Cr, Ni, Mo), the equations of the hyper surface in the four dimensional space. For the statistical and mathematical analysis, there were used 23 industrial cases. This study analyses iron rolls cast in the simplex procedure, in combined forms (iron chill, for the crust and moulding sand, for the necks of the rolls). The research included rolls from the semihard class, with hardness, between 33...59 Shore units (219...347 Brinell units) for the 0 and 1 hardness class, measured on the crust, respectively 59...75 Shore units (347...550 Brinell units), for the class 2 of hardness. This study is required because of the numerous defects, which cause rejection, since the phase of elaboration of the...

The Analysis by Finite Element Method (FEM), accomplished using ANSYS software, has the central aims to determine the behavior of a part's material, geometrically welldefined, of a mechanical, electrical, thermal assembly, subjected to any of external actions, such as physics, mechanical, thermal, electrical, and any other, well defined. The material behavior, under conditions well defined, i.e. geometrically or physically, is characterized by thermal deformation results in each element of the mesh, in every node of the network's element, respectively, subjected to charges due to boundary conditions (constraints and blocking, respectively, thermal or physical agents, external or internal).

In this study, measurements were carried out to identify the generation characteristics of wear particles emitted under a subway cabin during operation. Along with a fast mobility particle sizer, probes were installed under a subway cabin and in a subway tunnel to measure the size distributions of nanoparticles at 1-s intervals. Based on the particle density measured under the cabin minus that measured in the tunnel, the size distribution of wear particles generated under the cabin during deceleration was estimated to be bimodal at 165.5 nm and 6.98 nm. These particles were most likely generated from wheel-rail contact, as the train utilized electric braking (no mechanical force applied). In addition, a change in the wear mechanism appears to have arisen due to the increased temperature of the wheel-rail contact while nanoparticles were being emitted, leading to an initial generation of 165.5-nm particles followed by 6.98-nm particles 1 s later.

In this study, measurements were carried out to identify the generation characteristics of wear particles emitted under a subway cabin during operation. Along with a fast mobility particle sizer, probes were installed under a subway cabin and in a subway tunnel to measure the size distributions of nanoparticles at 1-s intervals. Based on the particle density measured under the cabin minus that measured in the tunnel, the size distribution of wear particles generated under the cabin during deceleration was estimated to be bimodal at 165.5 nm and 6.98 nm. These particles were most likely generated from wheel-rail contact, as the train utilized electric braking (no mechanical force applied). In addition, a change in the wear mechanism appears to have arisen due to the increased temperature of the wheel-rail contact while nanoparticles were being emitted, leading to an initial generation of 165.5-nm particles followed by 6.98-nm particles 1 s later.

Focusing strictly to the braking assembly system, it is an important key factor for safety, does not matter if it can be found on cars, motorcycles, planes or bicycles. The principal aspect is to transform the energies that act on the system, which are kinetic and potential, then leads to a speed decrease of the vehicle until it stops. The purpose of this paper is to analyze five possible variants of the geometry of the brake disc, each geometry being different from the other. Because for a more efficient release of heat, the five chosen geometries of the discs have on their surface vanes, holes, in order to remove heat from their surface. For the actual making of the discs, the chosen models were made and designed in the CATIA V5 design program. The next step in this work was to perform analyzes and simulations for the selected disks. At the same time, the material chosen for them was considered. The 3D models were imported into the ANSYS analysis program, where individual analyzes...

The following paper deals with the design and installation of braking system in the Go Kart. The braking system used here is a hydraulic disc brake. A single disc single caliper disc brake system has been used here. The purpose of this project is to design a braking system for a Go Kart that can produce efficient braking force so that in the competition i.e. IKC3 championship, it meets our desired braking output being a light vehicle as possible. We have been assisted by software like ANSYS and AUTOCAD for the design considerations and analysis of the braking system.

One area that has been examined for weight reduction is vehicle with braking system (BS). The greatest advantages of vehicles, is their ability to recover significant amounts of braking energy using a Braking System (BS). Braking is an effective method to extend brake disc life, minimise disc rotor weight, minimise brake pad wear and to extend the working range of a vehicle. Braking would extend the working range of an vehicle to provided that any extra energy consumption e.g. from increased vehicle mass and system losses did not outweigh the saving from energy recuperation, also reduce duty levels on the brakes themselves, giving advantages including extended brake rotor and friction material life, but more importantly reduced brake mass, minimise brake pad wear. The objective of this research is to define thermal performance on disc brake models. Thermal performance is a key factor which is studied using the model in Finite Element Analysis simulations. Ultimately a design method for brakes suitable for use on any car-sized vehicle was used from previous analysis. The design requirement, including reducing the thickness would affect the temperature distribution and increase stress at the critical area. Based on the relationship obtained between rotor weight, thickness, undercut effect and offset between hat and friction ring, criteria have been established for designing brake discs in a vehicle with braking.

The paper reports on a combined experimental and numerical investigation of the aero-thermal behavior of a vented automotive brake disc. The aim is to assess to which extent nowadays available CFD codes can be confidently used in the automotive brake disc design process. The reference experimental investigation provided the aero-thermal flow characteristics at the exit of a vented brake disc, with a pin type internal geometry and drilling holes. Tests were performed at one disc rotational speed and at several braking conditions. Star CD software was employed to compute the internal flow. Results were compared and discussed in terms of both global and local quantities. A general good agreement between numerical and experimental results was obtained. Thus CFD simulation was proved to be a very useful tool for brake disc designers.

In this study, high-hardness Silicon Nitride (Si 3 N 4) particles were spatially dispersed with aluminium A356 alloy, making A356 reinforced with 10 wt.% Si 3 N 4 Functionally Graded Metal Matrix Composite (A356-10 wt.% Si 3 N 4 FGMMC) through vertical centrifugal casting route. The gradient particle distribution and phase analysis were verified along the radial direction. The hardness and sliding wear behaviour were evaluated using VickerÕs microhardness tester and pin-on-disc tribometer. The superior microhardness (182 HV) was observed at the exterior surface, which was 73% higher than the interior surface. In the dissimilar zones of the FGMMC, wear performance was assessed with the applied loads of 20, 40, and 60 N at sliding velocities of 2, 3 and 4 m/s during the sliding distances of 500, 1250, and 2000 m. Taguchi's technique and Analysis of Variance (ANOVA) were implemented to pinpoint the optimum and momentous sliding wear variables. The lowest wear rate of 0.749 3 10 24 is identified at the ceramic wealthy zone with 20 N, 2 m/s, 500 m, and ANOVA analysis revealed that the various zones had a major impact (30.70%) followed by load (28.76%). The worn surface investigation confirmed the production of a stable tribo-oxide layer and revealed the enhanced wear resistance on the wealthy ceramic zone. The microstructural, hardness and wear experiment's findings confirmed the gradient distribution of Si 3 N 4 in the A356 alloy from the exterior to the interior surface, with a maximum in the exterior periphery.