WorldWideScience

Sample records for brake shoes

  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. 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. Real-time monitoring of brake shoe keys in freight cars

    Institute of Scientific and Technical Information of China (English)

    Rong ZOU; Zhen-ying XU; Jin-yang LI; Fu-qiang ZHOU

    2015-01-01

    Condition monitoring ensures the safety of freight railroad operations. With the development of machine vision technology, visual inspection has become a principal means of condition monitoring. The brake shoe key (BSK) is an important component in the brake system, and its absence will lead to serious accidents. This paper presents a novel method for automated visual inspection of the BSK condition in freight cars. BSK images are first acquired by hardware devices. The subsequent in-spection process is divided into three stages:first, the region-of-interest (ROI) is segmented from the source image by an im-proved spatial pyramid matching scheme based on multi-scale census transform (MSCT). To localize the BSK in the ROI, cen-sus transform (CT) on gradient images is developed in the second stage. Then gradient encoding histogram (GEH) features and linear support vector machines (SVMs) are used to generate a BSK localization classifier. In the last stage, a condition classifier is trained by SVM, but the features are extracted from gray images. Finally, the ROI, BSK localization, and condition classifiers are cascaded to realize a completely automated inspection system. Experimental results show that the system achieves a correct inspection rate of 99.2%and a speed of 5 frames/s, which represents a good real-time performance and high recognition accuracy.

  4. Shoe

    NARCIS (Netherlands)

    Flinterman, A.A.

    2009-01-01

    The invention relates to a shoe, comprising a front part and a back part, and provided with a sole, and an upper placed on the sole, wherein the sole incorporates a hinge pivotally connecting the front part and the back part, and wherein the upper is divided into a front upper and a back upper, whic

  5. Design of Multi-drill Machine Tool for Brake Shoe%制动蹄片多轴钻床设计

    Institute of Scientific and Technical Information of China (English)

    侯玉荣; 金兴伟; 钱俊

    2013-01-01

    Brake shoe is the key part of brake assembly, which has influence on brake assembly's quality. Through introducing the design and manufacture of main spindle box, bed and fixture of brake shoe multi-drill machine tool, the way, feasibility and economy of non-standard equipment design and manufacture in factories were explored.%制动蹄是影响制动器总成质量的关键部件.通过介绍制动蹄片多轴钻床主轴箱、床身、夹具的设计和制造,探讨了非标设备设计、制造的途径、可行性及经济性.

  6. 提升机闸瓦温度监测系统的研究%Temperature Monitoring System Research of Hoist Brake Shoe

    Institute of Scientific and Technical Information of China (English)

    沙永东; 李晓豁; 康晓敏; 侯静

    2012-01-01

    In order to effectively protect hoist brake shoe' s braking performance,improve the work reliability and service life, establishing temperature monitoring system of hoist brake shoe in braking process.This system consists of detection system and alarm, communication lines,host computer,etc. ,can be for hoist brake shoe online measurement temperature and real--time monitoring,with low energy consumption,small size,reliability and stability,information processing ability and other characteristics. The system for staff to provide effective reference data,can be according to the monitoring results related parameters in the fixed,ensure brake shoe under the premise of performance improved the safety and reliability of the brake system.%为了有效地保护提升机闸瓦的制动性能、提高其工作可靠性和使用寿命,建立了提升机闸瓦在制动过程中的温度监测系统,该系统由检测系统及报警器、通讯线路、上位机等组成,能对提升机闸瓦温度进行在线测量和实时监控,具有能耗低、体积小、可靠性和稳定性好,信息处理能力强等特点,该系统为工作人员提供了有效数据参考,可以根据监测结果及时进行相关参数的修正,在保证闸瓦性能的前提下提高了制动系统的安全可靠性。

  7. 计算机数据采集系统在提升机闸瓦制动工况分析中的应用%Application of Computer Data Acquisition System in Hoist Brake Shoe Braking Condition Analysis

    Institute of Scientific and Technical Information of China (English)

    潘武敏

    2013-01-01

    随着计算机数据处理技术的发展,数据采集系统应用到各大生产企业中。文章以矿井提升机制动问题为研究基础,提出了提升机闸瓦制动工况采集系统,通过对该系统的温度、压力以及速度传感器的选择及通信问题设计,实现了提升机闸瓦制动工况的实时数据采集,为今后的提升机制动问题分析提供了可靠的理论依据。%Along with the computer data processing technology development, data acquisition system is applied to the major work of enterprise.This article of mine hoist braking problems as the research foundation, developed to hoist brake shoe braking system.The system of temperature, pressure and speed sensor selection and communication design, realization of hoist brake shoe braking mode of the real-time data collection, for the future of the hoist braking problem analysis provides a reliable theoretical basis.

  8. Clutches and brakes design and selection

    CERN Document Server

    Orthwein, William C

    2004-01-01

    FRICTION MATERIALSFriction CodeWearBrake FadeFriction MaterialsNotationReferencesBAND BRAKESDerivation of EquationsApplicationLever-Actuated Band Brake: Backstop DesignExample: Design of a BackstopNotationFormula CollectionReferencesEXTERNALLY AND INTERNALLY PIVOTED SHOE BRAKESPivoted External Drum BrakesPivoted Internal Drum BrakesDesign of Dual-Anchor Twin-Shoe Drum BrakesDual-Anchor Twin-Shoe Drum Brake Design ExamplesDesign of Single-Anchor Twin-Shoe Drum BrakesSingle-Anchor Twin-Shoe Drum Brake Design Exam

  9. Experiment of Image Recognition of Railway Vehicle Brake Shoe Based on Edge Moment Invariants Matching Algorithm%边缘不变矩匹配算法的列车闸瓦图像识别试验

    Institute of Scientific and Technical Information of China (English)

    高向东; 伍世全; 王腾

    2011-01-01

    A new method for image recognition of train brake shoe based on edge moment invariants matching algorithm had been researched.The dynamic brake shoe images were taken by a vision sensor while the vehicle was moving.Then the statistic of brake shoe image invariant characteristics of rotation, scaling, and shift transformation were applied as the main features to automatically recognize the brake shoes with complicated background.With the presence of the characteristic similarity between the brake shoe surface and the wheel of vehicle,asymmetry of gray distribution of brake shoe images, object variation and occlusion of vehicle brake shoes, an improved moment invariants based on the edge-matching algorithm was proposed to recognize the brake shoe shape and analyze the brake shoe characteristics.The existing moment invariants algorithm was modified using the origin moment instead of central moments, and selected four lower order moments as the feature variable to reduce the calculation error.The experimental results show that the proposed method is effective for solving the above problems.The proposed algorithm can recognize the vehicle brake shoe automatically and can provide an effective way to solve the technical problems in long-standing recognition of the moving brake shoes.%研究一种基于边缘不变矩匹配算法的列车闸瓦图像识别新方法.在列车运动过程中,应用视觉传感器摄取闸瓦图像,根据闸瓦轮廓经图像旋转、缩放和平移变换后边缘特征点保持不变的统计特性,以其作为主要特征参数来自动识别具有复杂背景的闸瓦目标.针对闸瓦表面图像特征与轮对相近、图像灰度分布不均匀和存在遮挡等特点,研究改进的边缘不变矩匹配算法对闸瓦轮廓进行分析和特征提取,实现列车运动过程中闸瓦图像的识别.在传统不变矩算法计算的基础上,用原点矩代替中心矩,并且选用4个低阶矩作为特征分量,减少计算误差.

  10. SELF-REGULATION AND INTERNAL AND EXTERNAL PARAMETERS IN METAL BAND FRICTION PAIRS-SHOE BRAKES (PART 1

    Directory of Open Access Journals (Sweden)

    Volchenko N. A.

    2014-09-01

    Full Text Available We've illustrated self-regulation (based on the work function of the metal friction element and the regula-tion by quasiconstant unit loads on the contact patch of micropoints of metal-polymer friction pairs of band-block brake for the evaluation of process of their normal wear

  11. Research on temperature rise of hoisting machine disk brake

    Institute of Scientific and Technical Information of China (English)

    MA Jun; JANG Hai-bo

    2012-01-01

    A mathematical model and finite element model for analysis of temperature rise of the hoisting machine brake system was constructed,limit conditions were defined,and the law of temperature rise of brake shoes during emergent brake course was analyzed and calculated by using finite element software.By analyzing the calculation results,the law of temperature change of surface of brake disk and shoes during the braking process was found.The law of brake shoes surface temperature distribution and the law of temperature change along with thickness of brake shoes at brake time 0.5 s,1.0 s and 1.5 s was analyzed.A hoisting machine emergent braking test was carried out.Finally,the author concluded that velocity rebound in the process of hoisting machine emergent brake is due to decreased friction coefficient caused by the temperature rise of the brake shoes surface.

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

    OpenAIRE

    D. Rambabu; Gopinath, R; 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...

  13. 汽车刹车片用复合型金属陶瓷涂层制备及性能研究%Preparation and Property Study of Composite Cermet Coating Used in Automobile Brake Shoes

    Institute of Scientific and Technical Information of China (English)

    侯占祥; 靳清

    2012-01-01

    The Preparation process and application property of composite cermet coating used in automobile brake shoes were studied in this paper. A new type of WC-CoCr10/4 cermet powder that joint R&D with a domestic research institute were selected and the optimized HVOF spraying process were uesd to made coating directly on the braking disc. The study found that, using the composite cermet coating as a braking disc can make its tensile strength up to 75 Mpa above with brake pads, Microhardness can reach 1300 (HV0.3), at the same time, the coating has compact structure and low porosity, which not only improving the wearing resistance and significant extending the life of brake shoes, but also reduce the cost of production,. And the coatings fully meet the practical use requirements and have a broad application prospect.%本文进行了将复合型金属陶瓷涂层用于汽车刹车片的制备工艺与应用性能的初步研究。选用与国内某研究机构联合研制的新型WC—CoCr10/4金属陶瓷粉体作为刹车片材料并采用优化后的HVOF超音速火焰喷涂工艺直接在制动盘上制备,经研究发现,采用该复合涂层作为刹车片可以使其与制动盘之间的拉伸结合强度达到75Mpa以上,显微硬度可达HV0.31300,同时该涂层具有组织致密、孔隙率低等特点,在提高刹车片耐磨性、显著延长使用寿命的同时也降低了生产成本,完全满足实际使用需求,具有广阔的应用前景。

  14. 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.

  15. 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....

  16. 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.

  17. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Science.gov (United States)

    2010-10-01

    ... steering axle of a truck, truck-tractor or bus shall not be less than 4.8 mm (3/16 inch) at the shoe center....6 mm (1/16 inch) or less for hydraulic disc, drum and electric brakes. (2) Non-steering axle brakes... for drum brakes); or less than 3.2 mm (1/8 inch) for disc brakes. Hydraulic or electric...

  18. 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.

  19. Shoe allergic contact dermatitis.

    Science.gov (United States)

    Matthys, Erin; Zahir, Amir; Ehrlich, Alison

    2014-01-01

    Foot dermatitis is a widespread condition, affecting men and women of all ages. Because of the location, this condition may present as a debilitating problem to those who have it. Allergic contact dermatitis involving the feet is frequently due to shoes or socks. The allergens that cause shoe dermatitis can be found in any constituent of footwear, including rubber, adhesives, leather, dyes, metals, and medicaments. The goal of treatment is to identify and minimize contact with the offending allergen(s). The lack of product information released from shoe manufacturers and the continually changing trends in footwear present a challenge in treating this condition. The aim of this study is to review the current literature on allergic contact shoe dermatitis; clinical presentation, allergens, patch testing, and management will be discussed. PubMed and MEDLINE databases were used for the search, with a focus on literature updates from the last 15 years. PMID:25000234

  20. Wear Modalities and Mechanisms of the Mining Non-asbestos Composite Brake Material

    Science.gov (United States)

    Bao, Jiusheng; Yin, Yan; Zhu, Zhencai; Tong, Minming; Lu, Yuhao; Peng, Yuxing

    2013-08-01

    The mining brake material is generally made of composite materials and its wear has important influences on the braking performance of disc brakes. In order to improve the braking reliability of mine hoisters, this paper did some tribological investigations on the mining brake material to reveal its wear modalities and mechanisms. The mining non-asbestos brake shoe and 16Mn steel were selected as braking pairs and tested on a pad-on-disc friction tester. And a SEM was used to observe the worn surface of the brake shoe. It is shown that the non-asbestos brake material has mainly five wear modalities: adhesive wear, abrasive wear, cutting wear, fatigue wear and high heat wear. At the front period of a single braking the wear modality is mainly composed of some light mechanical wear such as abrasive, cutting and point adhesive. With the temperature rising at the back period it transforms to some heavy mechanical wear such as piece adhesive and fatigue. While in several repeated brakings once the surface temperature rises beyond the thermal-decomposition point of the bonding material, the strong destructive high heat wear takes leading roles on the surface. And a phenomenon called friction catastrophe (FC) occurs easily, which as a result causes a braking failure. It is considered that the friction heat has important influences on the wear modalities of the brake material. And the reduction of friction heat must be an effective technical method for decreasing wear and avoiding braking failures.

  1. Rocker shoe, minimalist shoe, and standard running shoe : A comparison of running economy

    NARCIS (Netherlands)

    Sobhani, Sobhan; Bredeweg, Steven; Dekker, Rienk; Kluitenberg, Bas; van den Heuvel, Edwin; Hijmans, Juha; Postema, Klaas

    2014-01-01

    Objectives: Running with rocker shoes is believed to prevent lower limb injuries. However, it is not clear how running in these shoes affects the energy expenditure. The purpose of this study was, therefore, to assess the effects of rocker shoes on running economy in comparison with standard and min

  2. GROUND REACTION FORCE DIFFERENCES BETWEEN RUNNING SHOES, RACING FLATS, AND DISTANCE SPIKES IN RUNNERS

    Directory of Open Access Journals (Sweden)

    Suzanna Logan

    2010-03-01

    Full Text Available Various shoes are worn by distance runners throughout a training season. This study measured the differences in ground reaction forces between running shoes, racing flats, and distance spikes in order to provide information about the potential effects of footwear on injury risk in highly competitive runners. Ten male and ten female intercollegiate distance runners ran across a force plate at 6.7 m·s-1 (for males and 5.7 m·s-1 (for females in each of the three types of shoes. To control for differences in foot strike, only subjects who exhibited a heel strike were included in the data analysis. Two repeated-measures ANOVAs with Tukey's post-hoc tests (p < 0.05 were used to detect differences in shoe types among males and females. For the males, loading rate, peak vertical impact force and peak braking forces were significantly greater in flats and spikes compared to running shoes. Vertical stiffness in spikes was also significantly greater than in running shoes. Females had significantly shorter stance times and greater maximum propulsion forces in racing flats compared to running shoes. Changing footwear between the shoes used in this study alters the loads placed on the body. Care should be taken as athletes enter different phases of training where different footwear is required. Injury risk may be increased since the body may not be accustomed to the differences in force, stance time, and vertical stiffness

  3. Wider Shoes for Wider Feet?

    Science.gov (United States)

    Meyer, Mary C.

    2006-01-01

    From a very young age, shoes for boys tend to be wider than shoes for girls. Is this because boys have wider feet, or because it is assumed that girls are willing to sacrifice comfort for fashion, even in elementary school? To assess the former, a statistician measures kids' feet. (Contains 2 tables and 3 figures.)

  4. 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.

  5. Little Lucy's Shoe

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Little Lucy is blue, She lost a nice shoe,What can little Lucy do?Go and buy another shoe.这首童谣读起来是不是很朗朗上口?blue,shoe.do非常押韵。现在.就请你试著将它译成中文E—mail或邮寄给我们吧,“最佳小诗人”等着你!

  6. Emergency braking : research summary.

    NARCIS (Netherlands)

    Schlösser, L.H.M.

    1976-01-01

    This report deals with an investigation concerning braking capacity of trucks if somewhere a failure occurs in the normal service brake. Purpose of research was to get an insight in various secondary braking systems for trucks. It is shown that with almost all of the secondary braking system it was

  7. Calculation of Temperature Fields of Electric Locomotive Wheels during Emergency Braking on Tangent Track at a Speed of 200 km/h

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    According to the heat transfer theory, an unsteady-state heat transfer model of electric locomotive wheels during emergency braking on tangent track at a speed of 200 km/h has been established in this paper. The explicit finite difference method is used in the numerical calculation of temperature fields of wheels. From the calculation results, the determination of braking distance and the material choice of brake shoes are discussed.

  8. Wuxia's Children Shoes sole: Touching Children's Heart

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Wuxia Children shoes sole company, founded in 1998, is the first professional children shoes sole business in Wenzhou city. It is located in Huanglong Commercial Center,Wenzhou city, Zhejiang province.

  9. 2007 World Shoes Forum in Biejing

    Institute of Scientific and Technical Information of China (English)

    Feng Yuan

    2007-01-01

    @@ 2007 Beijing Forum on World Shoes Industry opened grandly on 9th October.It is approved by Ministry of Commerce,sponsored by Trade Development Bureau of Ministry of Commerce,Pengrun International Fashion Centre,organizing committee of China International Shoes Fair,and assisted by Leather Association of Shenzhen,management committee of China Western Shoes garden of Chengdu.

  10. Compositions, Functions, and Testing of Friction Brake Materials and Their Additives

    Energy Technology Data Exchange (ETDEWEB)

    Blau, PJ

    2001-10-22

    The purpose of this report is to present a survey of commercial brake materials and additives, and to indicate their typical properties and functions, especially as regards their use in heavy trucks. Most truck pad and shoe materials described here were designed to wear against cast iron. Brake material test methods are also briefly described. This report does not address issues associated with the fabrication and manufacturing of brake materials. Since there are literally thousands of brake material additives, and their combinations are nearly limitless, it is impractical to list them all here. Rather, an attempt has been made to capture the primary constituents and their functions. An Appendix contains thermo-physical properties of some current and potential brake materials.

  11. Analysis of heat conduction in a drum brake system of the wheeled armored personnel carriers

    Science.gov (United States)

    Puncioiu, A. M.; Truta, M.; Vedinas, I.; Marinescu, M.; Vinturis, V.

    2015-11-01

    This paper is an integrated study performed over the Braking System of the Wheeled Armored Personnel Carriers. It mainly aims to analyze the heat transfer process which is present in almost any industrial and natural process. The vehicle drum brake systems can generate extremely high temperatures under high but short duration braking loads or under relatively light but continuous braking. For the proper conduct of the special vehicles mission in rough terrain, we are talking about, on one hand, the importance of the possibility of immobilization and retaining position and, on the other hand, during the braking process, the importance movement stability and reversibility or reversibility, to an encounter with an obstacle. Heat transfer processes influence the performance of the braking system. In the braking phase, kinetic energy transforms into thermal energy resulting in intense heating and high temperature states of analyzed vehicle wheels. In the present work a finite element model for the temperature distribution in a brake drum is developed, by employing commercial finite element software, ANSYS. These structural and thermal FEA models will simulate entire braking event. The heat generated during braking causes distortion which modifies thermoelastic contact pressure distribution drum-shoe interface. In order to capture the effect of heat, a transient thermal analysis is performed in order to predict the temperature distribution transitional brake components. Drum brakes are checked both mechanical and thermal. These tests aim to establish their sustainability in terms of wear and the variation coefficient of friction between the friction surfaces with increasing temperature. Modeling using simulation programs led eventually to the establishment of actual thermal load of the mechanism of brake components. It was drawn the efficiency characteristic by plotting the coefficient of effectiveness relative to the coefficient of friction shoe-drum. Thus induced

  12. know where the shoe pinches

    Institute of Scientific and Technical Information of China (English)

    周立

    2003-01-01

    英语对话: A:I now know where the shoe pinches for you.It is your husband who should be to blame for your son’s wrong doings. B:That’s why we have been at loggerheads with each other quite a lot re- cently.They all get on my nerves. A:Maybe you can talk sense into him and tell him the consequences. B:Everything I say falls on a deaf ear.

  13. KIDNEY ANOMALIES: HORSE SHOE KIDNEY

    OpenAIRE

    Hemalatha; Komarabattina; Nageshwar Rao; Kotikala Prabhakara

    2015-01-01

    INTRODUCTION : Horse Shoe Kidney was first recognized during an autopsy by De Carpi in 1521. This anomaly consists of two distinct renal masses lying vertically on either side of the midline and connected at their respective lower poles by a parenchymatous or fibrous isthmus that crosses the mid pl ane of the body. This isthmus lies at the level of 4th lumbar vertebra just beneath the origin of inferior mesenteric ...

  14. Muzzle brakes and their performance

    Directory of Open Access Journals (Sweden)

    J. P. Sirpal

    1958-01-01

    Full Text Available A criteria for the usefulness of a muzzle brake on any equipment is discussed and applied to existing weapons. Efficiencies of the existing muzzle brakes are also calculated. Design considerations for a muzzle brake are summarized.

  15. Discuss on Elevator Braking Capacity Assessment%电梯制动能力评估方法的探讨

    Institute of Scientific and Technical Information of China (English)

    邓剑鹏

    2015-01-01

    主要探讨电梯制动能力评估的方法。从制动器的国标检验要求、实际测试的制动数据以及制动器的出厂设置数据,总结出电梯紧急制动所体现的制动性能。在现场制动力测试中,如何排除曳引力对制动力测试数据的影响,以及在评估中影响制动力的关键因素:闸瓦接触面、机械结构、温升、电气控制、制动器的动作检测五个方面,论述评估中的注意事项。%This paper describes the elevator safety technology assessment of the braking capacity. According to the national standard requirements for braking inspection, actual braking test data and brake factory settings data, the braking performance in elevator emergency braking is summed up. In the ifeld test of braking force, it is discussed how to exclude the impact of the traction force on the braking test data, and the key factors affecting the braking force in the assessment: shoe contact surfaces, mechanical structure, temperature rise, electrical control, motion detection brakes, and the matters need attention in assessment.

  16. Patient compliance and effect of orthopaedic shoes

    DEFF Research Database (Denmark)

    Philipsen, A B; Ellitsgaard, N; Krogsgaard, M R;

    1999-01-01

    Orthopaedic shoes are individually handmade after a prescription from an orthopaedic surgeon, hence relatively expensive. Bad compliance is mentioned in the literature but not investigated. In order to evaluate patient compliance and the effect of orthopaedic shoes, 85 patients who were prescribe...

  17. In-shoe plantar tri-axial stress profiles during maximum-effort cutting maneuvers.

    Science.gov (United States)

    Cong, Yan; Lam, Wing Kai; Cheung, Jason Tak-Man; Zhang, Ming

    2014-12-18

    Soft tissue injuries, such as anterior cruciate ligament rupture, ankle sprain and foot skin problems, frequently occur during cutting maneuvers. These injuries are often regarded as associated with abnormal joint torque and interfacial friction caused by excessive external and in-shoe shear forces. This study simultaneously investigated the dynamic in-shoe localized plantar pressure and shear stress during lateral shuffling and 45° sidestep cutting maneuvers. Tri-axial force transducers were affixed at the first and second metatarsal heads, lateral forefoot, and heel regions in the midsole of a basketball shoe. Seventeen basketball players executed both cutting maneuvers with maximum efforts. Lateral shuffling cutting had a larger mediolateral braking force than 45° sidestep cutting. This large braking force was concentrated at the first metatarsal head, as indicated by its maximum medial shear stress (312.2 ± 157.0 kPa). During propulsion phase, peak shear stress occurred at the second metatarsal head (271.3 ± 124.3 kPa). Compared with lateral shuffling cutting, 45° sidestep cutting produced larger peak propulsion shear stress (463.0 ± 272.6 kPa) but smaller peak braking shear stress (184.8 ± 181.7 kPa), of which both were found at the first metatarsal head. During both cutting maneuvers, maximum medial and posterior shear stress occurred at the first metatarsal head, whereas maximum pressure occurred at the second metatarsal head. The first and second metatarsal heads sustained relatively high pressure and shear stress and were expected to be susceptible to plantar tissue discomfort or injury. Due to different stress distribution, distinct pressure and shear cushioning mechanisms in basketball footwear might be considered over different foot regions. PMID:25468303

  18. Contact allergens in shoe leather among patients with foot eczema

    NARCIS (Netherlands)

    van Coevorden, AM; Coenraads, PJ; Pas, HH; van der Valk, PGM

    2002-01-01

    Some patients with relapsing foot eczema and a shoe leather allergy, who fail to show positive results with standard series and shoe wear screening tray patch testing, do not respond to the use of hypoallergenic shoe leather. We assume that relevant allergens are present in hypoallergenic shoe leath

  19. Nonequilibrium tribology friction interaction of friction pairs of braking devices (part two)

    OpenAIRE

    ЖУРАВЛЕВ, Д. Ю.; Івано - Франківський національний технічний університет нафти і газу

    2016-01-01

    A robust approach to the analysis and design of band-shoe brake friction units of lifting andtransportation equipment is based on forecasting processes, phenomena and effects accompanyingtheir friction pairs. It includes the state of their surface and subsurface layers relating tothe quality of friction surfaces, durability and stabilization of operating parameters. In addition,it is observed regulation and control of operating parameters at electro-thermo-mechanicalfriction. The paper examin...

  20. The Changing Fate of Cloth Shoes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    ONE day I found by chance one of my old photos taken 30 years ago. In it I was still a serious 17-year-old girl with my hair in two short braids and dressed in a blue cloth coat, brown corduroys and a pair of black cloth shoes each fastened by a strap at the side My eyes fixed on the shoes and lingered for quite a long time. A smile quietly crawled over my lips. Isn't it the fashionable "little girl's shoe" which is expected to prevail in the market this year?

  1. Dream for a Pair of Shoes

    Institute of Scientific and Technical Information of China (English)

    江大洪; 章思英

    2005-01-01

    The boy was 1.7 meters tall when he just started his third year at primary school. As his feet had outgrown even Father's shoes,his parents had to look up and down the streets for size-46 shoes. At 16,he shot to a height of 2.2 meters,and no store or market in the whole of China had stock of size-53 shoes for his big feet. The parents watched rather alarmingly their son shooting up wildly like a sapling.

  2. 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.

  3. KINETIC ASSESSMENT OF GOLF SHOE OUTER SOLE DESIGN FEATURES

    Directory of Open Access Journals (Sweden)

    Rosemary J. Dyson

    2009-12-01

    Full Text Available This study assessed human kinetics in relation to golf shoe outer sole design features during the golf swing using a driver club by measuring both within the shoe, and beneath the shoe at the natural grass interface. Three different shoes were assessed: metal 7- spike shoe, alternative 7-spike shoe, and a flat soled shoe. In-shoe plantar pressure data were recorded using Footscan RS International pressure insoles and sampling at 500 Hz. Simultaneously ground reaction force at the shoe outer sole was measured using 2 natural grass covered Kistler force platforms and 1000 Hz data acquisition. Video recording of the 18 right-handed golfers at 200 Hz was undertaken while the golfer performed 5 golf shots with his own driver in each type of shoe. Front foot (nearest to shot direction maximum vertical force and torque were greater than at the back foot, and there was no significant difference related to the shoe type. Wearing the metal spike shoe when using a driver was associated with more torque generation at the back foot (p < 0. 05 than when the flat soled shoe was worn. Within shoe regional pressures differed significantly with golf shoe outer sole design features (p < 0.05. Comparison of the metal spike and alternative spike shoe results provided indications of the quality of regional traction on the outer sole. Potential golf shoe outer sole design features and traction were presented in relation to phases of the golf swing movement. Application of two kinetic measurement methods identified that moderated (adapted muscular control of foot and body movement may be induced by golf shoe outer sole design features. Ground reaction force measures inform comparisons of overall shoe functional performance, and insole pressure measurements inform comparisons of the underfoot conditions induced by specific regions of the golf shoe outer sole

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Heat distribution in disc brake

    Science.gov (United States)

    Klimenda, Frantisek; Soukup, Josef; Kampo, Jan

    2016-06-01

    This article is deals by the thermal analysis of the disc brake with floating caliper. The issue is solved by numerically. The half 2D model is used for solution in program ADINA 8.8. Two brake discs without the ventilation are solved. One disc is made from cast iron and the second is made from stainless steel. Both materials are an isotropic. By acting the pressure force on the brake pads will be pressing the pads to the brake disc. Speed will be reduced (slowing down). On the contact surface generates the heat, which the disc and pads heats. In the next part of article is comparison the maximum temperature at the time of braking. The temperatures of both materials for brake disc (gray cast iron, stainless steel) are compares. The heat flux during braking for the both materials is shown.

  9. 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.

  10. Horse-shoe Kidney - Approach to Treatment

    Directory of Open Access Journals (Sweden)

    R. L. Gupta, N. Saxena, Sharad Kumar, Monika Mahajan, Deepak Mahajan, Sonika.

    1999-01-01

    Full Text Available Horse-shoe kidney is a congenital anomaly which is associated with calculous formation andpelviureteric junction obstruction due to the abnormal lie of the pelvis and ureters. The patientpresents as pain in abdomen, recurrent urinary tract infection, lump in abdomen, haematuria andpyuria. Division of the isthmus and simultaneous nephropexy corrects the lie of the pelvis andureters and is recommended as the surgery for symptomatic horse-shoe kidney. If the pelviuretericjunction is dependent and funnel shaped, simple nephropexy in lower polar diversion position willsuffice but if there is high insertion of the ureter, some form of pyeloplasty is mandatory. Acontralateral nephropexy, at a later stage, is also recommended.

  11. 49 CFR 238.431 - Brake system.

    Science.gov (United States)

    2010-10-01

    ... brake system shall be designed to prevent thermal damage to wheels and brake discs. The operating... thermal damage to wheels or discs. (f) The brake system design shall allow a disabled train's pneumatic... a brake rate consistent with prevailing adhesion, passenger safety, and brake system...

  12. Unstable shoe construction: influence on gait and posture

    Directory of Open Access Journals (Sweden)

    Masood T

    2011-01-01

    Full Text Available Footwear, in one form or another, have been around for millennia. The advancements in the technology have made possible the transformation of animal skin and fur wrapped around feet by our ancestors into modern-day marvels of athletic shoes. Arguably one of the most pronounced innovations in the field of footwear design is the introduction of unstable shoe construction (USC, over the last few decades. Most widely investigated shoes are the Masai Barefoot Technology (MBT shoes. Numerous scientific studies conducted on these shoes have revealed their effects on human gait and posture in healthy and morbid populations.

  13. 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.

  14. 14 CFR 25.735 - Brakes and braking systems.

    Science.gov (United States)

    2010-01-01

    ... constructed so that: (1) If any electrical, pneumatic, hydraulic, or mechanical connecting or transmitting element fails, or if any single source of hydraulic or other brake operating energy supply is lost, it is... hydraulic system following a failure in, or in the vicinity of, the brakes is insufficient to cause...

  15. 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...

  16. An analysis of braking measures

    NARCIS (Netherlands)

    De Groot, S.; De Winter, J.C.F.; Wieringa, P.A.; Mulder, M.

    2010-01-01

    Braking to a full stop at a prescribed target position is a driving manoeuvre regularly used in experiments to investigate driving behaviour or to test vehicle acceleration feedback systems in simulators. Many different performance measures have been reported in the literature for analysing braking.

  17. [Shoe factory workers, solvents and health].

    Science.gov (United States)

    Foà, Vito; Martinotti, Irene

    2012-01-01

    Exposure to organic solvents in footwear manufacturing industry came from the glues used adhering the shoe parts to each other. Benzene was the first solvent used in shoe factories until the evidence of its capacity to cause leukaemia. Then, the demonstration that exposure to n-hexane was related to distal polyneuropathy limited the use of this substance. After that, results of neurotoxicological studies conducted on workers exposed to different mixtures of organic solvents make necessary prevention measure directed to a progressive reduction of air dispersion of these chemicals. Today exposure to solvents in workplaces is regulated by health based exposure limit values that should warranty absence of central nervous system effects. One of the most important rules of occupational medicine is verify that these exposure levels are really health protective also for workers with increased susceptibility. PMID:22697025

  18. Parameter Analysis on Torque Stabilization for the Eddy Current Brake: A Developed Model, Simulation, and Sensitive Analysis

    Directory of Open Access Journals (Sweden)

    Quan Zhou

    2015-01-01

    Full Text Available Eddy current brake (ECB is an attractive contactless brake whereas it suffers from braking torque attenuation when the rotating speed increases. To stabilize the ECB’s torque generation property, this paper introduces the concept of anti-magneto-motive force to develop the ECB model on the fundamental of magnetic circles. In the developed model, the eddy current demagnetization and the influence of temperature which make the braking torque attenuation are clearly presented. Using the developed model of ECB, the external and internal characteristics of the ECB are simulated through programming by MATLAB. To find the sensibility of the influences on ECB’s torque generation stability, the stability indexes are defined and followed by a sensibility analysis on the internal parameters of an ECB. Finally, this paper indicates that (i the stability of ECB’s torque generating property could be enhanced by obtaining the optimal combination of “demagnetization speed point and the nominal maximum braking torque.” (ii The most remarkable influencing factor on the shifting the demagnetization speed point of ECB was the thickness of the air-gap. (iii The radius of pole shoe’s cross section area and the distance from the pole shoe center to the rotation center are both the most significant influences on the nominal maximum braking torque.

  19. Radiation exposure from shoe-fitting fluoroscopes; Strahlenexposition bei Schuhdurchleuchtungsapparaten

    Energy Technology Data Exchange (ETDEWEB)

    Busch, Uwe [Deutsches Roentgen-Museum, Remscheid (Germany)

    2015-05-01

    It is 40 years ago that a very popular X-ray device disappeared in German shoe shops: the shoe-fitting fluoroscope or Pedoskop. Since the 1930s, these X-ray machines were an integral part of any good shoe business. Following the entry into force X-Ray Regulation (RoeV 1973) the use of these devices was prohibited in Germany.

  20. 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...

  1. Running shoes for relief of plantar pressure in diabetic patients.

    Science.gov (United States)

    Kästenbauer, T; Sokol, G; Auinger, M; Irsigler, K

    1998-06-01

    There is a causal relationship between diabetic foot ulceration, elevated plantar pressure, and severe sensory neuropathy. Cushioned footwear intended to relieve plantar pressure is well established for prevention and healing of plantar ulcers. The aim of the present study was to investigate whether pressure relief by means of a running shoe with optimized forefoot pressure damping is comparable to that of a custom-made soft insole placed into an in-depth shoe. The in-shoe pressures were compared to an in-depth shoe with the original cork insole and with a leather-soled Oxford shoe. The maximum reduction of plantar pressure in the running shoe was 47% under the 2nd and 3rd metatarsal heads, 29% at the first metatarsal head, and 32% at the great toe in comparison to the Oxford shoe. This was surpassed only by the custom-made insole, which reduced pressures at the metatarsal heads by 50%. The specially designed running shoe yielded the same pressure relief at the central metatarsal heads as the custom-made insole. Such shoes are likely to be very useful in preventing diabetic foot ulceration in high-risk patients as a comparatively affordable and immediately available device. PMID:9632129

  2. 49 CFR 238.231 - Brake system.

    Science.gov (United States)

    2010-10-01

    ... adhesion, passenger safety, and brake system thermal capacity. An emergency brake application shall be... are free of condemnable cracks. (g) Disc brakes shall be designed and operated to produce a surface... operating conditions; and (4) Operation of the friction brake alone does not result in thermal damage...

  3. 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.

  4. SensorShoe: Mobile Gait Analysis for Parkinson's Disease Patients

    NARCIS (Netherlands)

    Kauw-A-Tjoe, R.; Thalen, J.; Marin-Perianu, M.; Havinga, P.J.M.

    2007-01-01

    We present the design and initial evaluation of a mobile gait analysis system, SensorShoe. The target user group is represented by Parkinson's Disease patients, which need continuous assistance with the physical therapy in their home environment. SensorShoe analyses the gait by using a low-power sen

  5. SensorShoe: Mobile Gait Analysis for Parkinson's Disease Patients

    NARCIS (Netherlands)

    Havinga, P.J.M.; Kauw-A-Tjoe, R.G.; Marin-Perianu, M.; Thalen, J.P.

    2007-01-01

    We present the design and initial evaluation of a mobile gait analysis system, SensorShoe. The target user group is represented by Parkinson's Disease patients, which need continous assistance with the physical therapy in their home environment. SensorShoe analyses the gait by using a low-power sens

  6. The Electronic Wedge Brake - EWB

    Energy Technology Data Exchange (ETDEWEB)

    Ho, L.M.; Roberts, R.P.; Hartmann, H.; Gombert, B. [Siemens VDO Automotive (Germany)

    2006-07-01

    Future driver assistance systems will not only monitor the current traffic situation, but actively assist the driver in the day to day driving routines and as well in emergency situations. Autonomous intervention in the vehicle behavior will help to keep the vehicle under control, even in hazardous situations. A fast and smart braking system is one of the basics for the next generation of driver assistance systems. Siemens VDO sees its electronic wedge brake (EWB) brake-by-wire technology as the answer to future vehicle chassis safety, weight, reliability and space requirements. Particularly in the automobile sector, there is an increasing trend towards replacing existing hydraulic or pneumatic brake systems with drive 'by-wire' solutions. While mechatronics, i.e. intelligent, controllable electromechanical actuators, are already in use in many automotive and non automotive areas, there are particularly strict requirements for purely electromechanical braking systems which require complex development processes. These are highly safety critical systems, which must provide both excellent control quality and sophisticated fail-safe behavior. The challenge is to achieve a high power density in the wheel brake actuators. (orig.)

  7. Energy harvesting with piezoelectric applied on shoes

    Science.gov (United States)

    Camilloni, Enrico; Carloni, Mirko; Giammarini, Marco; Conti, Massimo

    2013-05-01

    In the last few years the continuous demand of energy saving has brought continuous research on low-power devices, energy storage and new sources of energy. Energy harvesting is an interesting solution that captures the energy from the environment that would otherwise be wasted. This work presents an electric-mechanical model of a piezoelectric transducer in a cantilever configuration. The model has been characterized measuring the acceleration and the open circuit voltage of a piezoelectric cantilever subjected to a sinusoidal force with different values frequency and subject to an impulsive force. The model has been used to identify the optimal position in which the piezoelectric cantilever has to be placed on a shoe in order to obtain the maximum energy while walking or running. As a second step we designed the DC-DC converter with an hysteresis comparator. The circuit is able to give energy to switch on a microprocessor for the amount of time long enough to capture and store the information required. The complete system has been implemented, installed on a shoe and used in a 10 Km running competition.

  8. 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.

  9. 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.

  10. The effect of shoe design and lateral wedging on knee loading

    DEFF Research Database (Denmark)

    Mølgaard, Carsten; Kersting, Uwe G.

    -dimensional gait analysis. Barefoot walking, walking in a running shoe, an Oxford-type leather shoe, and a rocker shoe were analyzed. The shoes were tested both with and without a 10-degree full length laterally wedged insole. Results: Similar, significant reductions in the peak knee adduction moment with lateral...

  11. Contact allergy in Indonesian patients with foot eczema attributed to shoes

    NARCIS (Netherlands)

    Febriana, S. A.; Soebono, H.; Coenraads, P. J.; Schuttelaar, M. L. A.

    2015-01-01

    BackgroundShoe dermatitis is a form of contact dermatitis resulting from exposure to shoes. Allergens and types of shoes responsible may vary depending on manufacturing techniques, climatic conditions and indigenous traditions. This study focuses primarily on as yet unexplored shoe dermatitis cases

  12. Effect of rocker shoes on plantar pressure pattern in healthy female runners

    NARCIS (Netherlands)

    Sobhani, Sobhan; van den Heuvel, Edwin; Bredeweg, Steven; Kluitenberg, Bas; Postema, Klaas; Hijmans, Juha M.; Dekker, Rienk

    2014-01-01

    Rocker profile shoes (rocker shoes) are one of the treatment options of metatarsalgia and forefoot stress fractures. The efficacy of rocker shoes in unloading the forefoot pressure has been shown in walking. In running, however, the effect of rocker shoes on forefoot pressure is unknown. Eighteen he

  13. Plantar pressure relief in the diabetic foot using forefoot offloading shoes

    NARCIS (Netherlands)

    S.A. Bus; R.W.M. van Deursen; R.V. Kanade; M. Wissink; E.A. Manning; J.G. van Baal; K.G. Harding

    2009-01-01

    Purpose: Forefoot offloading shoes (FOS) are commonly used in clinical practice for treatment of plantar forefoot ulcers in the diabetic foot. The aim of this study was to assess the offloading efficacy of four different FOS models in comparison with a cast shoe and control shoe. Methods: In-shoe pl

  14. 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.

  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. 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...

  17. 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.

  18. Braking performance of aircraft tires

    Science.gov (United States)

    Agrawal, Satish K.

    This paper brings under one cover the subject of aircraft braking performance and a variety of related phenomena that lead to aircraft hydroplaning, overruns, and loss of directional control. Complex processes involving tire deformation, tire slipping, and fluid pressures in the tire-runway contact area develop the friction forces for retarding the aircraft; this paper describes the physics of these processes. The paper reviews the past and present research efforts and concludes that the most effective way to combat the hazards associated with aircraft landings and takeoffs on contaminated runways is by measuring and displaying in realtime the braking performance parameters in the aircraft cockpit.

  19. Plastic shoe facilitates ultrasonic inspection of thin wall metal tubing

    Science.gov (United States)

    Lambermeyer, D. J.; Peterson, R. M.

    1967-01-01

    Plastic shoe aids inspection of thin walled stainless steel welded tubing to locate voids or other material defects in critical component equipment. Incorporated in available ultrasonic inspection equipment, it couples the transducer to the tube at desired incident angles.

  20. Parents: Avoid Kids Foot Problems with the Right Shoes

    Science.gov (United States)

    ... Print | Share Avoid Kids Foot Problems with the Right Shoes Before you head to the store to ... College of Foot and Ankle Surgeons (ACFAS), All Rights Reserved. Privacy Statement | Disclaimer | Terms and Conditions | Site ...

  1. Sporadic wind wave horse-shoe patterns

    Directory of Open Access Journals (Sweden)

    S. Yu. Annenkov

    1999-01-01

    Full Text Available The work considers three-dimensional crescent-shaped patterns often seen on water surface in natural basins and observed in wave tank experiments. The most common of these 'horse-shoe-like' patterns appear to be sporadic, i.e., emerging and disappearing spontaneously even under steady wind conditions. The paper suggests a qualitative model of these structures aimed at explaining their sporadic nature, physical mechanisms of their selection and their specific asymmetric form. First, the phenomenon of sporadic horse-shoe patterns is studied numerically using the novel algorithm of water waves simulation recently developed by the authors (Annenkov and Shrira, 1999. The simulations show that a steep gravity wave embedded into widespectrum primordial noise and subjected to small nonconservative effects typically follows the simple evolution scenario: most of the time the system can be considered as consisting of a basic wave and a single pair of oblique satellites, although the choice of this pair tends to be different at different instants. Despite the effective low-dimensionality of the multimodal system dynamics at relatively sho ' rt time spans, the role of small satellites is important: in particular, they enlarge the maxima of the developed satellites. The presence of Benjamin-Feir satellites appears to be of no qualitative importance at the timescales under consideration. The selection mechanism has been linked to the quartic resonant interactions among the oblique satellites lying in the domain of five-wave (McLean's class II instability of the basic wave: the satellites tend to push each other out of the resonance zone due to the frequency shifts caused by the quartic interactions. Since the instability domain is narrow (of order of cube of the basic wave steepness, eventually in a generic situation only a single pair survives and attains considerable amplitude. The specific front asymmetry is found to result from the interplay of quartic

  2. Developing of a software for determining advanced brake failures in brakes test bench

    Directory of Open Access Journals (Sweden)

    Hakan Köylü

    2016-08-01

    Full Text Available At present time, the brake test bench conducts the braking and suspension tests of front or rear axles and the test results are evaluated through one axle. The purpose of the brake testing system is to determine braking force and damping coefficient dissymmetry of one axle. Thus, this test system evaluates the performance of service brake, hand brake and suspension systems by considering separately front and rear axle dissymmetry. For this reason, the effects of different braking and damping forces applied by right and left wheels of both axles on braking performance of all vehicle are not determined due to available algorithm of the test bench. Also, the other brake failures are not occurred due to the algorithm of brake test system. In this study, the interface has been developed to determine the other effects of dissymmetry and the other brake failures by using the one axle results of brake test bench. The interface has algorithm computing the parameters according to the interaction between front and rear axles by only using measured test results. Also, it gives the warnings by comparing changes in the parameters with braking performance rules. Braking and suspension tests of three different vehicles have been conducted by using brake test bench to determine the performance of the algorithm. Parameters based on the axle interaction have been calculated by transferring brake test results to the interface and the test results have been evaluated. As a result, the effects of brake and suspension failures on braking performance of both axle and vehicle have been determined thanks to the developed interface.

  3. 49 CFR 393.49 - Control valves for brakes.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  4. 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...

  5. Mechanics of jazz shoes and their effect on pointing in child dancers.

    Science.gov (United States)

    Fong Yan, Alycia; Smith, Richard; Vanwanseele, Benedicte; Hiller, Claire

    2012-07-01

    There has been little scientific investigation of the impact of dance shoes on foot motion or dance injuries. The pointed (plantar-flexed) foot is a fundamental component of both the technical requirements and the traditional aesthetic of ballet and jazz dancing. The aims of this study were to quantify the externally observed angle of plantar flexion in various jazz shoes compared with barefoot and to compare the sagittal plane bending stiffness of the various jazz shoes. Sixteen female recreational child dancers were recruited for 3D motion analysis of active plantar flexion. The jazz shoes tested were a split-sole jazz shoe, full-sole jazz shoe, and jazz sneaker. A shoe dynamometer measured the stiffness of the jazz shoes. The shoes had a significant effect on ankle plantar flexion. All jazz shoes significantly restricted the midfoot plantar flexion angle compared with the barefoot condition. The split-sole jazz shoe demonstrated the least restriction, whereas the full-sole jazz shoe the most midfoot restriction. A small restriction in metartarsophalangeal plantar flexion and a greater restriction at the midfoot joint were demonstrated when wearing stiff jazz shoes. These restrictions will decrease the aesthetic of the pointed foot, may encourage incorrect muscle activation, and have an impact on dance performance.

  6. 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.

  7. 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.

  8. 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.

  9. [Compensation in leg length inequality with orthopedic shoe measures].

    Science.gov (United States)

    Meyer, P E; Petersen, D

    1992-06-01

    There are three different methods of compensating for differences in leg length. The first is the construction of special shoes, which is adequate for differences of up to about 3 cm. The heels can be either higher or lower, or a cork sole 5-10 mm thick can be incorporated, the shaft made higher, and supplementary features, such as aids to push-off, can also be implemented. The second method is the wearing of the classic orthopedic boot or shoe, in which the necessary compensation for the shorter leg is incorporated as a part of the orthopedic footwear. The third method is the construction of a shoe within a shoe, for which different designs have crystallized out for the five groups presented. All designs incorporate leather, the tried and tested material, next to the skin. Stabilizing components are made of fiberglass-reinforced synthetic resin or Thermoplast. New materials allow aesthetically acceptable orthopedic footwear. On average, such shoes are 25% lighter than conventional orthopedic boots. The stability and wear-resistance allow large perforations and open-toe designs, which has made it possible to solve the problem of ventilation. PMID:1508545

  10. Instrumented shoes for activity classification in the elderly.

    Science.gov (United States)

    Moufawad el Achkar, Christopher; Lenoble-Hoskovec, Constanze; Paraschiv-Ionescu, Anisoara; Major, Kristof; Büla, Christophe; Aminian, Kamiar

    2016-02-01

    Quantifying daily physical activity in older adults can provide relevant monitoring and diagnostic information about risk of fall and frailty. In this study, we introduce instrumented shoes capable of recording movement and foot loading data unobtrusively throughout the day. Recorded data were used to devise an activity classification algorithm. Ten elderly persons wore the instrumented shoe system consisting of insoles inside the shoes and inertial measurement units on the shoes, and performed a series of activities of daily life as part of a semi-structured protocol. We hypothesized that foot loading, orientation, and elevation can be used to classify postural transitions, locomotion, and walking type. Additional sensors worn at the right thigh and the trunk were used as reference, along with an event marker. An activity classification algorithm was built based on a decision tree that incorporates rules inspired from movement biomechanics. The algorithm revealed excellent performance with respect to the reference system with an overall accuracy of 97% across all activities. The algorithm was also capable of recognizing all postural transitions and locomotion periods with elevation changes. Furthermore, the algorithm proved to be robust against small changes of tuning parameters. This instrumented shoe system is suitable for daily activity monitoring in elderly persons and can additionally provide gait parameters, which, combined with activity parameters, can supply useful clinical information regarding the mobility of elderly persons.

  11. CFD Analysis Of Straight Ventilated Disc Brake

    Directory of Open Access Journals (Sweden)

    Nikhil K

    2016-05-01

    Full Text Available Brakes are the key pieces of a vehicle that plays an active role in safety and performance of the system. The study of aerodynamic cooling of a disc brake in real working condition of vehicle is important in present situations. Brake discs get very hot quickly, so it should be dissipated properly through different modes of heat transfer. Contributions of these heat transfer modes are different in different type of problems. The cooling transfer rates are different in vane surface and frictional surface of a disc brake. Also the temperature varies in each small interval of braking time. So a transient problem simulation is important to study the cooling of a disc brake when a vehicle decelerates from a particular speed. ANSYS CFX tool is used for the simulation of this transient problem.

  12. An Experimental Analysis of Brake Efficiency Using four Fluids in a Disc Brake System

    Directory of Open Access Journals (Sweden)

    Seth Daniel Oduro

    2013-02-01

    Full Text Available The paper studies disc brake failure in Mini-buses using an experimental analysis to test the maximum braking force when different brake fluids such as clean, less dirty, dirty and soapy water solution were used in the braking system. The experimental results clearly showed that the soap solution appears to be the best fluid as far as low viscosity and stability of viscosity with increase in temperature are concerned. However, the soap solution is not compatible with other fluid which makes it difficult to be substitute as a clean brake fluid. The result of the Thepra Universal Brake Testing Equipment used for the braking efficiency test indicated that a pedal brake of 117 kN produce a brake force of 0.96 kN for clean brake fluid, 0.91 kN for the less dirty, 0.85 kN for dirty and 1.44 kN for soap solution. The value of 1.44 kN which was achieved when the soap solution was used indicated a positive braking force and the indicating that soap solution could be used to produce a high pedal force within a very short time (about 10-30 min and can therefore be used only in case of emergency. The brake efficiency test indicated that under hot conditions the braking efficiency is reduced and the presence of air in the system renders the braking ineffective because higher pedal force was needed to be able to produce a significant braking force which is noted for causing brake failure.

  13. 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 ...

  14. 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...

  15. Patients’ expectations and actual use of custom-made orthopaedic shoes

    NARCIS (Netherlands)

    Netten, van Jaap J.; Jannink, Michiel J.A.; Hijmans, Juha M.; Geertzen, Jan H.B.; Postema, Klaas

    2010-01-01

    Objective: To investigate the association between patients’ expectations and the actual use of custom-made orthopaedic shoes. - Design: A prospective cohort study with internal comparison. - Setting: Twelve orthopaedic shoe companies. - Patients: During six months, consecutive patients who were p

  16. BRAKE TEST OF SiCp/A356 BRAKE DISK AND INTERPRETATION OF EXPERIMENTAL RESULTS

    Institute of Scientific and Technical Information of China (English)

    YANG Zhiyong; HAN Jianmin; LI Weijing; WANG Jinhua

    2007-01-01

    Material properties are obvious different between aluminum matrix composites and iron and steel materials. After the brake disk braked at the same speed, the average temperature of the aluminum brake disk is 1.5 times as high as one of iron and steel brake disk, the thermal expansion value of the aluminum brake disk is 2 times as big as one of iron and steel brake disk. Mechanical property of the material decreases with the temperature increasing generally during braking, on the other hand, the big thermal stress in the brake disk happens because the material expansion is constrained. Firstly, the reasons of the thermal stress generation and the fracture failure of brake disks during braking are analyzed qualitatively by virtue of three-bar stress frame and sandwich deformation principles in physic, and then the five constraints which cause the thermal stress are summarized. On the base of the experimental results on the 1:1 emergency brake test, the thermal stress and temperature fields are simulated; The behavior of the fracture failure is interpreted semi-quantitatively by finite element analysis. There is the coincident forecast for the fraction position in term of the two methods. In the end, in the light of the analysis and calculation results, it is the general principles observed by the structure design and assembly of the brake disk that are summarized.

  17. 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…

  18. Shoe rim and shoe buckle pseudotumor of the ankle in elite and professional figure skaters and snowboarders: MR imaging findings

    International Nuclear Information System (INIS)

    To review MR imaging of figure skaters and snowboarders presenting with painful soft-tissue swelling of the lateral supramalleolar region with a clinical provisional diagnosis of soft-tissue tumor. MR imaging was prospectively reviewed by two sub-specialized musculoskeletal radiologists. The findings were correlated with a second clinical review and examination of the shoe wear. The patients were four female athletes undergoing heavy training regimes, ranging in age between 16 and 25 years. Two patients were elite figure skaters, and two were professional snowboarders. Three patients had unilateral masses with pain, and one patient presented with bilateral clinical findings. MR imaging showed subcutaneous, focal soft-tissue masses of the supramalleolar region in five ankles at the same level above the ankle joint. MR imaging prompted a second clinical review and correlation with the shoe wear. The MR imaging findings correlated to the level of the shoe rim or shoe buckle in all patients, confirming the suspected MR imaging diagnosis of an impingement syndrome. All four sportswomen were training excessively, ignoring safety advice regarding training duration, timing of breaks, and shoe wear rotation. (orig.)

  19. Instrumented Shoes for Real-Time Activity Monitoring Applications.

    Science.gov (United States)

    Moufawad El Achkar, Christopher; Lenoble-Hoskovec, Constanze; Major, Kristof; Paraschiv-Ionescu, Anisoara; Büla, Christophe; Aminian, Kamiar

    2016-01-01

    Activity monitoring in daily life is gaining momentum as a health assessment tool, especially in older adults and at-risk populations. Several research-based and commercial systems have been proposed with varying performances in classification accuracy. Configurations with many sensors are generally accurate but cumbersome, whereas single sensors tend to have lower accuracies. To this end, we propose an instrumented shoes system capable of accurate activity classification and gait analysis that contains sensors located entirely at the level of the shoes. One challenge in daily activity monitoring is providing punctual and subject-tailored feedback to improve mobility. Therefore, the instrumented shoe system was equipped with a Bluetooth® module to transmit data to a smartphone and perform detailed activity profiling of the monitored subjects. The potential applications of such a system are numerous in mobility and fall risk-assessment as well as in fall prevention. PMID:27332298

  20. [The shoe industry: from productive reality to risk individualization].

    Science.gov (United States)

    Saretto, Gianni; Dulio, Sergio

    2012-01-01

    This article describes in detail each stage of the shoe manufacturing process: design, cutting and shearing, sewing and trimming, assemblage, sole preparation, finishing, packaging and stocking, shoe manufacturing with synthetic materials. It will then discuss new technologies and their impact on the improvement of the worker's health, safety and convenience. A definition of the shoe parts and of the materials and machinery employed in its production will be provided, as well as a synthesis of the occupational hazards involved in each department. Although dealing with competitors who can take advantage of low-cost production and lack of concern for labour protection and environmental issues, the industry should always take great care of topics such as innovation and automation, but also workplace health and safety, while pushing the limits of that technological advance which companies have to face. PMID:22697024

  1. [The shoe industry: from productive reality to risk individualization].

    Science.gov (United States)

    Saretto, Gianni; Dulio, Sergio

    2012-01-01

    This article describes in detail each stage of the shoe manufacturing process: design, cutting and shearing, sewing and trimming, assemblage, sole preparation, finishing, packaging and stocking, shoe manufacturing with synthetic materials. It will then discuss new technologies and their impact on the improvement of the worker's health, safety and convenience. A definition of the shoe parts and of the materials and machinery employed in its production will be provided, as well as a synthesis of the occupational hazards involved in each department. Although dealing with competitors who can take advantage of low-cost production and lack of concern for labour protection and environmental issues, the industry should always take great care of topics such as innovation and automation, but also workplace health and safety, while pushing the limits of that technological advance which companies have to face.

  2. Modified distal shoe appliance--fabrication and clinical performance.

    Science.gov (United States)

    Gujjar, Kumar Raghav; Indushekar, K R; Amith, H V; Sharma, Shefali Li

    2012-01-01

    When the primary second molar is prematurely lost, mesial movement and migration of the permanent first molar often occurs. This is one of the most difficult problems of the developing dentition confronted by pediatric dentists. Use of a space maintainer that will guide the permanent first molar into its normal position is indicated. In cases with bilateral premature loss of primary molars, the conventional design of distal shoe poses a variety of problems and, therefore, necessitates a customized design for the eruption guidance of permanent first molars. The purpose of this case report is to discuss an innovative design of a distal shoe appliance, which was used with good clinical results.

  3. 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.

  4. 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.

  5. Foot motion in children shoes: a comparison of barefoot walking with shod walking in conventional and flexible shoes.

    Science.gov (United States)

    Wolf, Sebastian; Simon, Jan; Patikas, Dimitrios; Schuster, Waltraud; Armbrust, Petra; Döderlein, Leonhard

    2008-01-01

    The increased prevalence for flatfoot and hallux valgus in modern societies may be the consequence of inadequate footwear in childhood. Based on the assumption that barefoot walking represents the best condition for the development of a healthy foot the objective of this study was to monitor the influence of commercial footwear on children's foot motion during walking. Furthermore, an attempt was made to reduce this influence by changing the physical properties of standard footwear. Children's barefoot motion pattern was monitored by a marker-based optical 3D-tracking method using a multi-segment foot model. In the study's first stage, barefoot walking was compared to walking with a commercial product. In the second stage it was compared to both, the pattern with the commercial product and with the shoe modified on the basis of the findings of the first stage of the study. Eighteen children (8.2+/-0.7 years old) with no foot deformity and with the same shoe size were recruited for this study. It was found that tibio-talar ROM increased in the commercial shoe (26.6 degrees ) compared to the barefoot condition (22.5 degrees , p=0.001) whereas the medial arch changes for push-off were diminished since the variation in arch length was reduced from 9.9% (barefoot) to 5.9% (shoe, pstudy shows that slimmer and more flexible children's shoes do not change foot motion as much as conventional shoes and therefore should be recommended not only for children in this age but for healthy children in general.

  6. Impact of Brake Pad Structure on Temperature and Stress Fields of Brake Disc

    Directory of Open Access Journals (Sweden)

    Guoshun Wang

    2013-01-01

    Full Text Available Utilizing ABAQUS finite element software, the study established the relationship between a brake pad structure and distributions of temperature and thermal stress on brake disc. By introducing radial structure factor and circular structure factor concepts, the research characterized the effect of friction block radial and circumferential arrangement on temperature field of the brake disc. A method was proposed for improving heat flow distribution of the brake disc through optimizing the position of the friction block of the brake pad. Structure optimization was conducted on brake pads composed of 5 or 7 circular friction blocks. The result shows that, with the same overall contact area of friction pair, an appropriate brake pad structure can make the friction energy distribute evenly and therefore lowers peak temperature and stress of the brake disc. Compared with a brake pad of 7 friction blocks, an optimized brake pad of 5 friction blocks lowered the peak temperature of the corresponding brake disc by 4.9% and reduced the highest stress by 10.7%.

  7. Effect of surface texture and working gap on the braking performance of the magnetorheological fluid brake

    Science.gov (United States)

    Wang, Na; Li, Dong Heng; Li Song, Wan; Chao Xiu, Shi; Zhi Meng, Xiang

    2016-10-01

    In this paper, the effect of the surface textures of braking disc on the braking performance is experimentally investigated under the conditions of different working gaps and applied currents. For this purpose, a new configuration of magnetorheological fluid brake (MRB) with adjustable working gap is developed to improve the manufacturing accuracy and cost, and to reduce the problem of replacing the braking disc. In addition, the braking discs with three types of surface texture are designed and machined. Based on the test bed developed for the proposed MRB, a series of experiments are carried out on the manufactured prototype and the results are presented to obtain the relationship among the surface texture of the braking disc, applied current, working gap and the braking performance. The results show that the braking torque is significantly influenced by the working gap and surface texture of the braking disc, and the maximum braking torque is obtained on the conditions of 0.25 mm working gap and the braking disc with square surface texture.

  8. Braking index of isolated pulsars

    Science.gov (United States)

    Hamil, O.; Stone, J. R.; Urbanec, M.; Urbancová, G.

    2015-03-01

    Isolated pulsars are rotating neutron stars with accurately measured angular velocities Ω , and their time derivatives that show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of detailed debate, the commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR) from a rotating magnetized body. Other processes, including the emission of gravitational radiation, and of relativistic particles (pulsar wind), are also being considered. The calculated energy loss by a rotating pulsar with a constant moment of inertia is assumed proportional to a model dependent power of Ω . This relation leads to the power law Ω ˙ =-K Ωn 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 braking index within the MDR model. Four microscopic equations of state are employed as input to two different computational codes that solve Einstein's equations numerically, either exactly or using the perturbative Hartle-Thorne method, to calculate the

  9. Electronic Brake-Force Distribution Control Methods of ABS-Equipped Vehicles During Cornering Braking

    Institute of Scientific and Technical Information of China (English)

    WANG Guo-ye; LIU Zhao-du; MA Yue-feng; QI Zhi-quan

    2007-01-01

    Based on the dynamics of ABS-equipped vehicles during cornering braking,the electronic brakeforce distribution (EBD) control methods of ABS-equipped vehicles during cornering braking are proposed.According to the dynamics and the tire model under tire adhesion limit,the stability acceptance criteria of vehicles during cornering braking are proposed.According to the stability acceptance criteria and the ABS control,the EBD control methods of ABS-equipped vehicles during cornering braking are implemented by adjusting the threshold values of tires slip independently.The vehicle states during cornering braking at two typical initial velocities of the vehicle are analyzed by the EBD control methods,whose results indicate the EBD control methods can improve the braking performances of the vehicle during cornering braking comparing with the ABS control.

  10. 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...

  11. 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

  12. 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...

  13. 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...

  14. THE DEVELOPMENT OF TROLLEYBUS DRIVE BRAKE SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. Safonau

    2011-01-01

    Full Text Available The requirements for trolleybuses brake systems are analyzed. Some results of the studies examined, contemporary trends of developing in this direction are shows. The range of problems whose solution is aimed at creating high-performance brake systems whose increase efficiency and safety of trolleybuses determined.

  15. 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.

  16. The distal shoe space maintainer chairside fabrication and clinical performance.

    Science.gov (United States)

    Brill, Warren A

    2002-01-01

    The chairside-fabricated distal shoe appliance, with a stainless steel crown as the retainer, is an efficacious and cost-effective appliance for guiding the unerupted permanent first molar into position after premature loss or extraction of the second primary molar. The fabrication technique is illustrated in this case report and data is presented on the success rate of the appliance.

  17. Experimental Study of Heat Dissipation in Indoor Sports Shoes

    NARCIS (Netherlands)

    Dessing, O.; Jansen, A.J.; Leihitu, C.; Overhage, D.

    2014-01-01

    As indoor sports shoes are intensively used in a warm and sweaty environment for periods of up to three consecutive hours, the built-up heat inside is insufficiently released causing warm and perspiring feet. This results in an increased chance of blisters and skin irritations. Experimental research

  18. Shoe That Works As a Mobile Phone Inventecd

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    澳洲一名电脑工程师发明了一部鞋子手机,既能当鞋穿.又能当手机用。 A shoe that also works as a mobile phone has been invented by an Australian scientist, in a move reminiscent of spoof spy films.

  19. Effect Of Running Shoes on Foot Impact During Running

    CERN Document Server

    Nassif, Henry

    2016-01-01

    Running is part of almost every sport, and requires a great amount of stamina, endurance, mental toughness and overall strength. At every step, the foot experiences ground reaction forces necessary to support the motion of the body. With the advancements in shoe technology, running shoes have grown in popularity among runners, as well as non-runners, because they reduce the risk of injuries from the impact felt by the foot. The purpose of this report is to analyze the effect of running shoes on impact forces on the foot. This is achieved through the use of three force pads fixed at different locations on the foot The force measured by each sensor is then used to estimate the vertical ground reaction force, using the sensors' calibrations equations . Based on the ground reaction force, the effective mass corresponding to the momentum change occurring during the transient phase of the impact is estimated. The results show that running at 9 miles per hour without running shoes generates an effective mass of (14....

  20. Tactile shoe inlays for high speed pressure monitoring

    DEFF Research Database (Denmark)

    Drimus, Alin; Mátéfi-Tempfli, Stefan

    2015-01-01

    This work describes the development of flexible tactile sensor shoe inlays for humanoid robots. Their design is based on a sandwich structure of flexible layers with a thin sheet of piezoresistive rubber as main transducer element. The layout and patterning of top and bottom electrodes give 1024...

  1. Effect of shoe type on plantar pressure: A gender comparison

    NARCIS (Netherlands)

    R.M. Queen; A.N. Abbey; J.I. Wiegerinck; J.C. Yoder; J.A. Nunley

    2010-01-01

    Despite the differences in materials, racing flats have begun to be used not only for racing, but also for daily training. As there are data suggesting a gender difference in overuse injuries in runners, shoe choice may affect loading patterns during running. The purpose was to determine differences

  2. Biomechanics of slow running and walking with a rocker shoe

    NARCIS (Netherlands)

    Sobhani, Sobhan; Hijmans, Juha; van den Heuvel, Edwin; Zwerver, Johannes; Dekker, Rienk; Postema, Klaas

    2013-01-01

    Evidence suggests a link between the loading of the Achilles tendon and the magnitude of the ankle internal plantar flexion moment during late stance of gait, which is clinically relevant in the management of Achilles tendinopathy. Some studies showed that rocker shoes can reduce the ankle internal

  3. 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.

  4. 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...

  5. Frictional Performance and Temperature Rise of a Mining Nonasbestos Brake Material during Emergency Braking

    Directory of Open Access Journals (Sweden)

    Jiusheng Bao

    2015-01-01

    Full Text Available By simulating emergency braking conditions of mine hoisters, tribological experiments of a mining nonasbestos brake material sliding on E355CC steel friction disc investigated a pad-on-disc friction tester. It is shown that, under combined influence of braking velocity and pressure, the lubricating film and micro-convex-apices on wear surface would have complex physicochemical reactions which make the instant friction coefficient rise gradually while the instant surface temperature rises first and then falls. With the antifriction effect from lubricating film and the desquamating of composite materials, the mean friction coefficient decreases first, then rises, and decreases again with the increasing of initial braking velocity. And with the existence of micro-convex-apices and variation from increment ratio of load and actual contacting area, it rises first and then falls with the increasing of braking pressure. However, the mean surface temperature rises obviously with the increasing of both initial braking velocity and braking pressure for growth of transformed kinetic energy. It is considered that the friction coefficient cannot be considered as a constant when designing brake devices for mine hoisters. And special attention should be paid to the serious influence of surface temperature on tribological performance of brake material during emergency braking.

  6. An Experimental Analysis of Brake Efficiency Using Four Fluids in a Drum Brake System

    Directory of Open Access Journals (Sweden)

    Prince Owusu-Ansah

    2014-06-01

    Full Text Available This paper studies drum brake failure in Mini-buses using an experimental analysis to test the viscosities and the maximum braking force when different fluids such as clean, less dirty, dirty and soapy water solution were used in the braking system. The effects of each of these fluids when successive increments in pedal force were applied at hot and cold conditions for drum brakes were studied. The results of the Thepra Universal Brake Testing Equipment used for the braking efficiency test indicated that a pedal force of 110 kN produce a brake force of 0.61 kN for clean fluid, 0.56 kN for less dirty, 0.51 kN for dirty and 0.92 kN. The value of 0.92 kN which was achieved when the soapy water solution was used indicated a positive braking force and that soap water solution could be used to produce a high pedal force within a very short time (10-30 min and can therefore be used only in case of emergency. It was observed that the clean brake fluid gave the best braking force followed by the less dirty and finally the dirty brake fluid. In a situation where air has been trapped in the system under hot condition with or without a servo unit, clean brake fluid performed much better at least three times better than the other three fluids. For soap solution, braking was effective only when it was operated at cold condition but less effective when the system was hot. Soap solution is therefore not reliable when used for a very long time but effective only for emergency situations.

  7. 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.

  8. 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.

  9. 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...

  10. 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...

  11. 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...

  12. Abnormal Sound Generated by the Braking of Steel Rim of Moped Wheel%踏板车钢制轮圈制动异响问题探析

    Institute of Scientific and Technical Information of China (English)

    何宇; 魏赫; 刘莉

    2012-01-01

    Home-made mopeds are usually fitted with steel rims and drum discs. That easily generates harsh abnormal sound due to the mismatch of materials of brake shoes and brake hubs. The materials for brake hub has direct influence on braking performance, such as the heat conduction rate, and vibration reduction etc. The best solution for this problem is to optimize the structure of wheel and use proper materials.%国内小踏板车常配置钢制辐板轮圈并采用鼓式制动,在骑乘,特别是制功时,常会伴有刺耳的异响声。产生异响的主要原因是轮圈制动毂本身材质与制动蹄块材料匹配不好,制动毂材质的选取直接影响制动时的热导率、消振性能,引起不良噪声。要想解决该问题,主要取决于轮圈的结构形式、材料选用等,但具体问题还要具体分析,针对性地解决。

  13. Current-generating 'double layer shoe' with a porous sole.

    Science.gov (United States)

    Kolomeisky, Anatoly B; Kornyshev, Alexei A

    2016-11-23

    We present a principle and a simple theory of a novel reverse electroactuator, in which the electrical current is generated by pumping an electrolytic liquid into nonwetting pores of a polarized electrode. The theory establishes the relationship between the variation of external pressure and the electrical current. The effective current density is amplified by the high porosity of the electrode. The suggested principle can be implemented into the design of a shoe which will generate an AC current simply by walking. Estimates of typical parameters and operation regimes of such a device suggest that one can easily generate a peak current density of ~17 mA cm(-2). This would produce some 1.7 A from each shoe at 0.65 W average power density, without hampering walking. PMID:27624878

  14. 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.

  15. BREATHING SHOES AND COMPLEMENTARITIES: STRATEGIC INNOVATION IN A MATURE INDUSTRY

    OpenAIRE

    ARNALDO CAMUFFO; ANDREA FURLAN; PIETRO ROMANO; ANDREA VINELLI

    2008-01-01

    This paper tells the story of Geox, an Italian footwear manufacturer that, in less than a decade, has become one of the world's largest shoe manufacturers. Applying the related notions of complementarity and performance landscape to study strategic positioning in the footwear industry, we show that, though grounded on product innovation (the original Geox breathes® patented system which allows ventilation in waterproof rubber sole), Geox's competitive advantage has not grown out of operationa...

  16. Bimanual robot manipulation and packaging of shoes in footwear industry

    OpenAIRE

    Morales, Ricardo; Badesa, Francisco J.; García-Aracil, Nicolás; Bormann, Richard; Fischer, Jan; Graf, Birgit

    2014-01-01

    The present paper presents the ongoing research undertaken as a research experiment, called HERMES, inside Echord european integrated project framework. The goal of the HERMES experiment is to study, analyze and finally implement the packaging of shoes on a robot system that mimics the required degree of flexibility and dexterity provided by the human workers. The use of a bimanual system with anthropomorphic hands has been chosen as it could also be applied to solve other processes of simila...

  17. A Shoe-Embedded Piezoelectric Energy Harvester for Wearable Sensors

    OpenAIRE

    Jingjing Zhao; Zheng You

    2014-01-01

    Harvesting mechanical energy from human motion is an attractive approach for obtaining clean and sustainable electric energy to power wearable sensors, which are widely used for health monitoring, activity recognition, gait analysis and so on. This paper studies a piezoelectric energy harvester for the parasitic mechanical energy in shoes originated from human motion. The harvester is based on a specially designed sandwich structure with a thin thickness, which makes it readily compatible wit...

  18. 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...

  19. Does the Shoe Fit? Ethical, Legal, and Policy Considerations of Global Positioning System Shoes for Individuals with Alzheimer's Disease.

    Science.gov (United States)

    Yang, Y Tony; Kels, Charles G

    2016-08-01

    As the overall incidence of Alzheimer's disease rises, the burden on caregivers and law enforcement institutions will increase to find individuals who wander. As such, technological innovations that could reduce this burden will become increasingly important. One such innovation is the GPS Shoe. As with any innovation involving the transfer of personal data to third parties, potential pitfalls with respect to loss of privacy and inadequate consent counterbalance the substantial promise of GPS shoes. To some extent, advance planning can mitigate these concerns, wherein individuals willingly elect to be monitored before their impairments progress to a stage that makes such authorization impractical. Nonetheless, tension may arise between the peace of mind of caregivers and family members and other important considerations at the intersection of autonomy, privacy, dignity, and consent. Ultimately, confronting ethical, legal, and policy considerations at the front end of product development and deployment will help ensure that new technologies are used wisely and that their lifesaving potential is realized. PMID:27394035

  20. Does the Shoe Fit? Ethical, Legal, and Policy Considerations of Global Positioning System Shoes for Individuals with Alzheimer's Disease.

    Science.gov (United States)

    Yang, Y Tony; Kels, Charles G

    2016-08-01

    As the overall incidence of Alzheimer's disease rises, the burden on caregivers and law enforcement institutions will increase to find individuals who wander. As such, technological innovations that could reduce this burden will become increasingly important. One such innovation is the GPS Shoe. As with any innovation involving the transfer of personal data to third parties, potential pitfalls with respect to loss of privacy and inadequate consent counterbalance the substantial promise of GPS shoes. To some extent, advance planning can mitigate these concerns, wherein individuals willingly elect to be monitored before their impairments progress to a stage that makes such authorization impractical. Nonetheless, tension may arise between the peace of mind of caregivers and family members and other important considerations at the intersection of autonomy, privacy, dignity, and consent. Ultimately, confronting ethical, legal, and policy considerations at the front end of product development and deployment will help ensure that new technologies are used wisely and that their lifesaving potential is realized.

  1. 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.

  2. 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.

  3. Effects of an unstable shoe construction on balance in women aged over 50 years

    DEFF Research Database (Denmark)

    Ramstrand, Nerrolyn; Thuesen, Anna Helena; Nielsen, Dennis Brandborg;

    2010-01-01

    BACKGROUND: Shoes with an unstable sole construction are commonly used as a therapeutic tool by physiotherapists and are widely available from shoe and sporting goods retailers. The aim of this study was to investigate the effects of using an unstable shoe (Masai Barefoot Technology) on standing...... balance, reactive balance and stability limits. METHODS: Thirty-one subjects agreed to participate in the study and underwent balance tests on three different occasions. After test occasion one (baseline) 20 subjects received Masai Barefoot Technology shoes and were requested to wear them as much...

  4. Adherence to wearing therapeutic shoes among people with diabetes: a systematic review and reflections

    Science.gov (United States)

    Jarl, Gustav; Lundqvist, Lars-Olov

    2016-01-01

    Introduction Therapeutic shoes are prescribed to prevent diabetic foot ulcers, but adherence to wearing the shoes is often poor. Aim The aim of this study was to review the literature on factors that are associated with adherence to wearing therapeutic shoes and construct a model of adherence to aid future research and development in the field. Methods We conducted a systematic search in PubMed, CINAHL, and PsycINFO for quantitative studies on factors associated with adherence to wearing therapeutic shoes among people with diabetes. Results Six studies were included in the review. The studies focused mainly on patient-, therapy-, and condition-related adherence factors. There is some evidence (three to five studies) that sex, diabetes duration, and ulcer history are not associated with adherence. The evidence for or against the other factors was weak (only one or two studies) or conflicting. Conclusion There is no conclusive evidence for using any factor to predict adherence to wearing therapeutic shoes, but there is some evidence against using certain factors for predicting adherence. Future studies should include a broader range of factors, including health system and social/economic factors, and they should investigate perceived costs and benefits of wearing therapeutic shoes in comparison with other shoes or no shoes. A seesaw model is presented illustrating the complex phenomenon of adherence. Further research is needed to identify factors associated with adherence to wearing therapeutic shoes, to enable the development of interventions to improve adherence and thereby reduce ulceration rates among people with diabetic foot complications.

  5. On the safety of braking mine up-haulage devices

    Energy Technology Data Exchange (ETDEWEB)

    Murzin, V.A.; Samusia, V.I.

    1982-01-01

    Experiments conducted on several mine up-haulage devices to analyze breakdowns due to the operator who quickly turned on the brake showed that sudden braking may really invoke maximum brake application on the machine winding much earlier than preventive braking and may lead to shutdown. It was concluded that in the Safety Regulations or Engineering Regulations that use of the handbrake should be more clearly outlined to preclude breakdown. One method of prevention is to develop and use a diagram showing build-up and magnitude of the braking moment when using the manual brake.

  6. 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...

  7. The effect of shoe design and lateral wedges on knee load and neuromuscular control in healthy subjects during walking

    DEFF Research Database (Denmark)

    Mølgaard, Carsten Møller; Kersting, Uwe G.

    2013-01-01

    design/type on the effectiveness of lateral wedging has not been investigated so far. The Purpose of the present study was to explore alterations in knee loading due to lateral foot wedges in three different shoes. Methods: Thirteen healthy participants with no history of knee pain were tested using...... three-dimensional gait analysis. Barefoot walking, walking in a running shoe, an Oxford-type leather shoe, and a rocker shoe were analysed. The shoes were tested both with and without a 10-degree full-length laterally wedged insole. Results: There were significant shoe wedge interactions on the first...... and second peak knee adduction moments. However, the variability of this moment between shoe designs was of similar magnitude as the effect of laterally wedged insoles. Only marginal changes in muscle activity for gastrocnemius when walking with the wedged Oxford shoe were revealed. Conclusion: Lateral...

  8. 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.)

  9. 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.

  10. 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.

  11. TPR鞋用材料%TPR shoe materials

    Institute of Scientific and Technical Information of China (English)

    郑玉婴

    2001-01-01

    The paper reports the composition, processing techniques, property and application performance, low temperature resistance and high strength of TPR materials. The materials can be used for different types of shoes.%分析了TPR鞋用材料的配方、工艺、性能.实验结果表明,该材料具有高弹性、耐低温、粘结强度牢等特点,适用于生产中高档运动鞋和旅游鞋鞋底.

  12. Importance of marketing in organizational success : Bata shoe company Zimbabwe

    OpenAIRE

    Gwindi, Hayden

    2013-01-01

    The purpose of this thesis is to investigate the marketing factors (if any) that have led to the survival of Bata Shoe Company in the struggling economy of Zimbabwe. For my data collection I used mostly phone calls, Skype interviews and researched documentation. After having all the data gathered a decision was made to use a qualitative approach since it enables me to obtain more in-depth information and has a few restrictions and assumptions on the data collected. Marketing Is a key fact...

  13. Tailor made business models: The case of tailor made shoes

    OpenAIRE

    Botková, Lívia

    2014-01-01

    The goal of this thesis is to draft business plan for mass customized online shoes shop, analysing the potential of the idea and profitability of business model. (I) First part of the thesis is theoretical background and it is divided in three chapters: (1) background on what is business model and how to write a business plan, (2) mass customization and (3) online shopping. At the end of every theoretical chapter there is practical implication for the business plan of the new venture. (II) Se...

  14. 某型履带车辆制动器磨损规律研究及寿命预测%Wear Rule Research and Life Prediction of a Certain Tracked Vehicle Brake

    Institute of Scientific and Technical Information of China (English)

    孙玉豹

    2013-01-01

      基于虚拟样机技术,用ADAMS/ATV模块建立了某型履带车辆紧急制动的动力学模型。通过紧急制动仿真,提取了车辆速度曲线及制动器打滑时间,计算了不同工况下各档位的滑磨功,进而求出其磨损量和寿命。由仿真及计算结果可知,制动瓦较制动鼓的磨损量大,这是由材料性质所决定的。制动时车辆的初速度越小,其磨损量就越小,寿命越长;反之,制动初速度越大,其磨损量就越大,寿命越短。%Based on virtual prototyping technology, emergency braking dynamic model of a certain tracked vehicle was established by means of ADAMS/ATV software. By emergency braking simulation, extracted curves of the vehicle speed and the brake slip time, calculated the friction work of all the gears on different conditions, and calculated the wear amount and life. Simulation and calculation results show that the wear amount of brake shoe is bigger than brake drum's, which is determined by the material properties. The lower the initial speed of the vehicle when braking, its wear amount is smaller and its life is longer. Contrarily, the higher the initial speed of the vehicle when braking, its wear amount is greater and its life is shorter.

  15. Running with a minimalist shoe increases plantar pressure in the forefoot region of healthy female runners

    NARCIS (Netherlands)

    Bergstra, S. A.; Kluitenberg, B.; Dekker, R.; Bredeweg, S. W.; Postema, K.; Van den Heuvel, E. R.; Hijmans, J. M.; Sobhani, S.

    2015-01-01

    OBJECTIVES: Minimalist running shoes have been proposed as an alternative to barefoot running. However, several studies have reported cases of forefoot stress fractures after switching from standard to minimalist shoes. Therefore, the aim of the current study was to investigate the differences in pl

  16. Patients' expectations and actual use of custom-made orthopaedic shoes

    NARCIS (Netherlands)

    van Netten, Jaap J.; Jannink, Michiel J. A.; Hijmans, Juha M.; Geertzen, Jan H. B.; Postema, Klaas

    2010-01-01

    Objective: To investigate the association between patients' expectations and the actual use of custom-made orthopaedic shoes. Design: A prospective cohort study with internal comparison. Setting: Twelve orthopaedic shoe companies. Patients: During six months, consecutive patients who were provided w

  17. Analysis of Reference and Influence of Shoes Culture in the East and the West

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Abook once noted that: Shoes is the art that combines Lcommodity, spirit and materiallife. It not merely reflects aesthetic consciousness decided by world view and sense of worth, but also the time essence and the emotion expression of designer. After attentive contemplation, it should admit that the author holds deep understanding towards the culture of shoes.

  18. Aging of running shoes and its effect on mechanical and biomechanical variables: implications for runners.

    Science.gov (United States)

    Chambon, Nicolas; Sevrez, Violaine; Ly, Quoc Hung; Guéguen, Nils; Berton, Eric; Rao, Guillaume

    2014-01-01

    This study investigates the effect of running shoes' aging on mechanical and biomechanical parameters as a function of midsole materials (viscous, intermediate, elastic) and ground inclination. To this aim, heel area of the shoe (under calcaneal tuberosity) was first mechanically aged at realistic frequency and impact magnitudes based on a 660 km training plan. Stiffness (ST) and viscosity were then measured on both aged and matching new shoes, and repercussions on biomechanical variables (joint kinematics, muscular pre-activation, vertical ground reaction force and tibial acceleration) were assessed during a leg-extended stepping-down task designed to mimic the characteristics of running impacts. Shoes' aging led to increased ST (means: from 127 to 154 N ∙ mm(-1)) and decreased energy dissipation (viscosity) (means: from 2.19 to 1.88 J). The effects induced by mechanical changes on body kinematics were very small. However, they led with the elastic shoe to increased vastus lateralis pre-activation, tibial acceleration peak (means: from 4.5 g to 5.2 g) and rate. Among the three shoes tested, the shoe with intermediate midsole foam provided the best compromise between viscosity and elasticity. The optimum balance remains to be found for the design of shoes regarding at once cushioning, durability and injury prevention. PMID:24576090

  19. STS-44 OV-104's airlock hatch with tennis shoes and Presidential Sports Award

    Science.gov (United States)

    1991-01-01

    STS-44 airlock hatch is decorated with two pairs of tennis shoes and a Presidential Sports Award Jogging patch (insignia) on the middeck of Atlantis, Orbiter Vehicle (OV) 104. With the crew having a treadmill-like device onboard for exercise and biomedical testing, tennis shoes were in plentiful stock on the eight-day mission.

  20. Influence of basketball shoe mass, outsole traction, and forefoot bending stiffness on three athletic movements.

    Science.gov (United States)

    Worobets, Jay; Wannop, John William

    2015-09-01

    Prior research has shown that footwear can enhance athletic performance. However, public information is not available on what basketball shoe properties should be selected to maximise movement performance. Therefore, the purpose of the study was to investigate the influence of basketball shoe mass, outsole traction, and forefoot bending stiffness on sprinting, jumping, and cutting performance. Each of these three basketball shoe properties was systematically varied by ± 20% to produce three shoe conditions of varying mass, three conditions of varying traction, and three conditions of varying bending stiffness. Each shoe was tested by 20 recreational basketball players completing maximal effort sprints, vertical jumps, and a cutting drill. Outsole traction had the largest influence on performance, as the participants performed significantly worse in all tests when traction was decreased by 20% (p < 0.001), and performed significantly better in the cutting drill when traction was increased by 20% (p = 0.005). Forefoot bending stiffness had a moderate effect on sprint and cutting performance (p = 0.013 and p = 0.016 respectively) and shoe mass was found to have no effect on performance. Therefore, choosing a shoe with relatively high outsole traction and forefoot bending stiffness should be prioritised, and less concern should be focused on selecting the lightest shoe.

  1. Effect of shoes containing nanosilica particles on knee valgus in active females during landing

    Directory of Open Access Journals (Sweden)

    Zahra Bassiri

    2015-01-01

    Full Text Available Objective(s: The effect of silica nanoparticles (SNPs in sport shoes outsoles on the  parameters related to anterior cruciate ligament (ACL Injury has not been investigated. The aim of this study was to investigate the effect of shoes outsole containing a composite of thermoplastic elastomer based on styrene-butadiene and silica nanoparticles (TPEN shoe on Knee Valgus Angle (KVA as a risk factor of ACL injuries during landing Materials and Methods: Fourteen active healthy women without knee injuries and disorders performed bilateral drop jump (DJ and single leg drop landing (SLL tasks in barefoot, wearing shoes fabricated with polyvinyl chloride outsole (PVC shoe and TPEN shoes conditions , randomly. The knee valgus angle values of right and left legs were calculated in the landing conditions. Two factors repeated measures ANOVA were used to investigate the effect of landing and footwear conditions on KVA of right and left legs.  Results: For both left and right limbs, the KVA was at maximum and minimum values during landing with barefoot and TPEN shoes, respectively. PVC shoe significantly reduced the knee valgus by 3.84% in left and 4.18% in right knee (P

  2. 浅谈创意概念鞋对鞋类设计的影响%Discuss the Influence of Concept Shoes on Shoes' Design

    Institute of Scientific and Technical Information of China (English)

    马英华; 辛东升; 王福娟; 庞士龙

    2013-01-01

    The concept shoes are created for designers' purpose of higher psychological demands.In recent years,the development of individual and perceptual market has reinforced its commercialization process.Theconcept shoes have become the tools of brand promotion.The concept shoes'model,color,material and pattern can be used in popular shoes'design.%概念鞋是设计师为实现更高层次心理诉求而创意的鞋靴.近几年随着个性化、高感度市场的发展,其商业化进程加剧,更成为品牌宣传的工具.概念鞋在造型、材质、色彩、图案等方面为大众化鞋靴提供了创新设计思维.

  3. 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

  4. 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...

  5. 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...

  6. 49 CFR 238.315 - Class IA brake test.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Class IA brake test. 238.315 Section 238.315... Requirements for Tier I Passenger Equipment § 238.315 Class IA brake test. (a) Except as provided in paragraph (b) of this section, either a Class I or a Class IA brake test shall be performed: (1) Prior to...

  7. Adherence to wearing therapeutic shoes among people with diabetes: a systematic review and reflections

    Directory of Open Access Journals (Sweden)

    Jarl G

    2016-08-01

    Full Text Available Gustav Jarl,1,2 Lars-Olov Lundqvist2 1Department of Prosthetics and Orthotics, Faculty of Medicine and Health, 2University Health Care Research Center, Faculty of Medicine and Health, Örebro University, Örebro, Sweden Introduction: Therapeutic shoes are prescribed to prevent diabetic foot ulcers, but adherence to wearing the shoes is often poor.  Aim: The aim of this study was to review the literature on factors that are associated with adherence to wearing therapeutic shoes and construct a model of adherence to aid future research and development in the field. Methods: We conducted a systematic search in PubMed, CINAHL, and PsycINFO for quantitative studies on factors associated with adherence to wearing therapeutic shoes among people with diabetes. Results: Six studies were included in the review. The studies focused mainly on patient-, therapy-, and condition-related adherence factors. There is some evidence (three to five studies that sex, diabetes duration, and ulcer history are not associated with adherence. The evidence for or against the other factors was weak (only one or two studies or conflicting. Conclusion: There is no conclusive evidence for using any factor to predict adherence to wearing therapeutic shoes, but there is some evidence against using certain factors for predicting adherence. Future studies should include a broader range of factors, including health system and social/economic factors, and they should investigate perceived costs and benefits of wearing therapeutic shoes in comparison with other shoes or no shoes. A seesaw model is presented illustrating the complex phenomenon of adherence. Further research is needed to identify factors associated with adherence to wearing therapeutic shoes, to enable the development of interventions to improve adherence and thereby reduce ulceration rates among people with diabetic foot complications.Keywords: Patient compliance, shoes, foot ulcer, diabetic foot, diabetes

  8. 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.

  9. A shoe-embedded piezoelectric energy harvester for wearable sensors.

    Science.gov (United States)

    Zhao, Jingjing; You, Zheng

    2014-07-11

    Harvesting mechanical energy from human motion is an attractive approach for obtaining clean and sustainable electric energy to power wearable sensors, which are widely used for health monitoring, activity recognition, gait analysis and so on. This paper studies a piezoelectric energy harvester for the parasitic mechanical energy in shoes originated from human motion. The harvester is based on a specially designed sandwich structure with a thin thickness, which makes it readily compatible with a shoe. Besides, consideration is given to both high performance and excellent durability. The harvester provides an average output power of 1 mW during a walk at a frequency of roughly 1 Hz. Furthermore, a direct current (DC) power supply is built through integrating the harvester with a power management circuit. The DC power supply is tested by driving a simulated wireless transmitter, which can be activated once every 2-3 steps with an active period lasting 5 ms and a mean power of 50 mW. This work demonstrates the feasibility of applying piezoelectric energy harvesters to power wearable sensors.

  10. A Shoe-Embedded Piezoelectric Energy Harvester for Wearable Sensors

    Directory of Open Access Journals (Sweden)

    Jingjing Zhao

    2014-07-01

    Full Text Available Harvesting mechanical energy from human motion is an attractive approach for obtaining clean and sustainable electric energy to power wearable sensors, which are widely used for health monitoring, activity recognition, gait analysis and so on. This paper studies a piezoelectric energy harvester for the parasitic mechanical energy in shoes originated from human motion. The harvester is based on a specially designed sandwich structure with a thin thickness, which makes it readily compatible with a shoe. Besides, consideration is given to both high performance and excellent durability. The harvester provides an average output power of 1 mW during a walk at a frequency of roughly 1 Hz. Furthermore, a direct current (DC power supply is built through integrating the harvester with a power management circuit. The DC power supply is tested by driving a simulated wireless transmitter, which can be activated once every 2–3 steps with an active period lasting 5 ms and a mean power of 50 mW. This work demonstrates the feasibility of applying piezoelectric energy harvesters to power wearable sensors.

  11. A shoe-embedded piezoelectric energy harvester for wearable sensors.

    Science.gov (United States)

    Zhao, Jingjing; You, Zheng

    2014-01-01

    Harvesting mechanical energy from human motion is an attractive approach for obtaining clean and sustainable electric energy to power wearable sensors, which are widely used for health monitoring, activity recognition, gait analysis and so on. This paper studies a piezoelectric energy harvester for the parasitic mechanical energy in shoes originated from human motion. The harvester is based on a specially designed sandwich structure with a thin thickness, which makes it readily compatible with a shoe. Besides, consideration is given to both high performance and excellent durability. The harvester provides an average output power of 1 mW during a walk at a frequency of roughly 1 Hz. Furthermore, a direct current (DC) power supply is built through integrating the harvester with a power management circuit. The DC power supply is tested by driving a simulated wireless transmitter, which can be activated once every 2-3 steps with an active period lasting 5 ms and a mean power of 50 mW. This work demonstrates the feasibility of applying piezoelectric energy harvesters to power wearable sensors. PMID:25019634

  12. 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...

  13. BRAKING PROCESS OF ENDURO AND HIGHWAY-TOURIST MOTORBIKES

    Directory of Open Access Journals (Sweden)

    Paweł SKRZYPCZYK

    2015-06-01

    Full Text Available In the event of an emergency, head of the motorcycle has a split second to decide what to do defensive maneuver. The most common choice is the braking maneuver. Starting motorcycle braking is associated with the selection of additional brake, which uses a driver. It is here to choose to use the front brake, rear or both simultaneously. The paper presents the study of the effects of such decision on the braking process. Tests were carried out for enduro and highway-tourist motorbikes.

  14. 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.

  15. 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

  16. A High Braking Index for a Pulsar

    CERN Document Server

    Archibald, R F; Ferdman, R D; Kaspi, V M; Guillot, S; Harrison, F A; Keane, E F; Pivovaroff, M J; Stern, D; Tendulkar, S P; Tomsick, J A

    2016-01-01

    We present a phase-coherent timing solution for PSR J1640-4631, a young 206 ms pulsar using X-ray timing observations taken with NuSTAR. Over this timing campaign, we have measured the braking index of PSR J1640-4631 to be n = 3.15+/-0.03. Using a series of simulations, we argue that this unusually high braking index is not due to timing noise, but is intrinsic to the pulsar's spin-down. We cannot, however, rule out contamination due to an unseen glitch recovery, although the recovery timescale would have to be longer than most yet observed. If this braking index is eventually proven to be stable, it demonstrates that pulsar braking indices greater than 3 are allowed in nature, hence other physical mechanisms such as mass or magnetic quadrupoles are important in pulsar spin-down. We also present a 3-sigma upper limit on the pulsed flux at 1.4 GHz of 0.018 mJy.

  17. 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.

  18. A HIGH BRAKING INDEX FOR A PULSAR

    Energy Technology Data Exchange (ETDEWEB)

    Archibald, R. F.; Ferdman, R. D.; Kaspi, V. M.; Tendulkar, S. P. [Department of Physics and McGill Space Institute, McGill University, 3600 University Street, Montréal, QC H3A 2T8 (Canada); Gotthelf, E. V. [Columbia Astrophysics Laboratory, 550 West 120th Street, New York, NY 10027-6601 (United States); Guillot, S. [Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 782-0436 Macul, Santiago (Chile); Harrison, F. A. [Cahill Center for Astrophysics, California Institute of Technology, 1216 East California Boulevard, Pasadena, CA 91125 (United States); Keane, E. F. [SKA Organization, Jodrell Bank Observatory, Cheshire SK11 9DL (United Kingdom); Pivovaroff, M. J. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550-9234 (United States); Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Tomsick, J. A. [Space Science Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450 (United States)

    2016-03-01

    We present a phase-coherent timing solution for PSR J1640–4631, a young 206 ms pulsar using X-ray timing observations taken with NuSTAR. Over this timing campaign, we have measured the braking index of PSR J1640–4631 to be n = 3.15 ± 0.03. Using a series of simulations, we argue that this unusually high braking index is not due to timing noise, but is intrinsic to the pulsar's spin-down. We cannot, however, rule out contamination due to an unseen glitch recovery, although the recovery timescale would have to be longer than most yet observed. If this braking index is eventually proven to be stable, it demonstrates that pulsar braking indices greater than three are allowed in nature; hence, other physical mechanisms such as mass or magnetic quadrupoles are important in pulsar spin-down. We also present a 3σ upper limit on the pulsed flux at 1.4 GHz of 0.018 mJy.

  19. 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...

  20. 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.

  1. 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...

  2. 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...

  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.

  4. Modeling and design of cooperative braking in electric and hybrid vehicles using induction machine and hydraulic brake

    Directory of Open Access Journals (Sweden)

    Zaini Dalimus

    2016-07-01

    Full Text Available In mixed-mode braking applications, the electric motor / generator (M/G and hydraulic pressure valve are controlled to meet the driver’s braking demand. Controlling these braking elements is achieved by modulating the current generated by the M/G and adjusting the fluid pressure to the wheel brake cylinders. This paper aims to model and design combined regenerative and hydraulic braking systems which, comprise an induction electric machine, inverter, NiMH battery, controller, a pressure source, pressure control unit, and brake calipers. A 15 kW 1500 rpm induction machine equipped with a reduction gear having a gear ratio of 4 is used. A hydraulic brake capable to produce fluid pressure up to 40 bar is used. Direct torque control and pressure control are chosen as the control criteria in the M/G and the hydraulic solenoid valve. The braking demands for the system are derived from the Federal Testing Procedure (FTP drive cycle. Two simulation models have been developed in Matlab®/Simulink® to analyze the performance of the control strategy in each braking system. The developed model is validated through experiment. It is concluded that the control system does introduce torque ripple and pressure oscillation in the braking system, but these effects do not affect vehicle braking performance due to the high frequency nature of pressure fluctuation and the damping effect of the vehicle inertia. Moreover, experiment results prove the effectiveness of the developed model.

  5. The use of running shoes to reduce plantar pressures in patients who have diabetes.

    Science.gov (United States)

    Perry, J E; Ulbrecht, J S; Derr, J A; Cavanagh, P R

    1995-12-01

    We compared the plantar pressures generated by walking in leather-soled Oxford-style shoes and by walking in inexpensive running shoes with those generated by walking in thin socks on a hard surface for thirty-nine individuals (thirteen who had diabetes and neuropathy, and thirteen who had diabetes without neuropathy, and thirteen who had neither diabetes nor neuropathy [controls]). Except for two anatomical regions, the plantar pressure associated with the Oxford-style shoes were not different from those associated with walking without shoes. In comparison, the inexpensive running shoes relieved plantar pressure in the forefoot and heel by a mean (and standard deviation) of 31 +/- 9.1 per cent, with the most relief occurring in the feet that had the highest pressures when they were unshod. There were significant reductions in pressure in all regions of the foot except for the midfoot (p leather-soled Oxford-style shoes because of the risk of ulceration due to elevated plantar pressures. Inexpensive running shoes should be viewed as the very minimally acceptable choice for footwear for these individuals if the feet are free of deformity. PMID:8550649

  6. The effect of shoe design and lateral wedges on knee load and neuromuscular control in healthy subjects during walking

    DEFF Research Database (Denmark)

    Mølgaard, Carsten; Kersting, Uwe G.

    2014-01-01

    The increasing number of patients with developing osteoarthritis is accompanied by a growing scientific interest in non-operative early treatment strategies. It is generally believed that laterally wedged insoles can change the distribution of knee loading. However, the importance of footwear...... three-dimensional gait analysis. Barefoot walking, walking in a running shoe, an Oxford-type leather shoe, and a rocker shoe were analysed. The shoes were tested both with and without a 10-degree full-length laterally wedged insole. Results: There were significant shoe wedge interactions on the first...... and second peak knee adduction moments. However, the variability of this moment between shoe designs was of similar magnitude as the effect of laterally wedged insoles. Only marginal changes in muscle activity for gastrocnemius when walking with the wedged Oxford shoe were revealed. Conclusion: Lateral...

  7. 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

  8. The effect of shoe type on gait in forefoot strike runners during a 50-km run

    Directory of Open Access Journals (Sweden)

    Mark E. Kasmer

    2014-06-01

    Conclusion: More runners adopted a more posterior initial contact area after the 50-km run in the traditional shoe type than in the minimalist shoe type. The runners who adopted a more posterior initial contact area were more closely associated with an increased median frequency of the medial gastrocnemius, which suggests there may be a change in motor unit recruitment pattern during long-distance, sustained velocity running. The increased peak pressures observed in the medial forefoot in the minimalist shoe type may predispose to metatarsal stress fractures in the setting of improper training.

  9. Evaluation of the accuracy of shoe fitting in older people using three-dimensional foot scanning

    OpenAIRE

    Menz, Hylton B; Auhl, Maria; Ristevski, Sonja; Frescos, Nicoletta; Munteanu, Shannon E

    2014-01-01

    Background Ill-fitting footwear is a common problem in older people. The objective of this study was to determine the accuracy of shoe fitting in older people by comparing the dimensions of allocated shoes to foot dimensions obtained with a three-dimensional (3D) scanner. Methods The shoe sizes of 56 older people were determined with the Brannock device®, and weightbearing foot scans were obtained with the FotoScan 3D scanner (Precision 3D Ltd, Weston-super-mare, UK). Participants were provid...

  10. 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.

  11. Single chip interrogation system for a smart shoe wireless transponder.

    Science.gov (United States)

    Sheibani, Shahrzad; Roshan, Meisam; Huang, Haiying; Banerjee, Bhaskar; Henderson, Rashaunda

    2014-01-01

    The objective of this paper is to design a wireless transponder for antenna-based sensors that can be used to simultaneously measure shear and pressure forces for diabetic foot diagnosis. The transponder will be placed on the top surface of a shoe and consists of sensor antennas and an identification system that transmits information to a receiver by modulating the signal reflected by the antennas sensor in the insole. The identification system includes an energy harvester, a crystal oscillator and a passive mixer. A single chip interrogation circuit has been designed in IBM130 nm CMOS technology to reduce size. The identification system including bond pads has a size of 1.2 mm × 0.8 mm. PMID:25570659

  12. Single chip interrogation system for a smart shoe wireless transponder.

    Science.gov (United States)

    Sheibani, Shahrzad; Roshan, Meisam; Huang, Haiying; Banerjee, Bhaskar; Henderson, Rashaunda

    2014-01-01

    The objective of this paper is to design a wireless transponder for antenna-based sensors that can be used to simultaneously measure shear and pressure forces for diabetic foot diagnosis. The transponder will be placed on the top surface of a shoe and consists of sensor antennas and an identification system that transmits information to a receiver by modulating the signal reflected by the antennas sensor in the insole. The identification system includes an energy harvester, a crystal oscillator and a passive mixer. A single chip interrogation circuit has been designed in IBM130 nm CMOS technology to reduce size. The identification system including bond pads has a size of 1.2 mm × 0.8 mm.

  13. Low Power Shoe Integrated Intelligent Wireless Gait Measurement System

    Science.gov (United States)

    Wahab, Y.; Mazalan, M.; Bakar, N. A.; Anuar, A. F.; Zainol, M. Z.; Hamzah, F.

    2014-04-01

    Gait analysis measurement is a method to assess and identify gait events and the measurements of dynamic, motion and pressure parameters involving the lowest part of the body. This significant analysis is widely used in sports, rehabilitation as well as other health diagnostic towards improving the quality of life. This paper presents a new system empowered by Inertia Measurement Unit (IMU), ultrasonic sensors, piezoceramic sensors array, XBee wireless modules and Arduino processing unit. This research focuses on the design and development of a low power ultra-portable shoe integrated wireless intelligent gait measurement using MEMS and recent microelectronic devices for foot clearance, orientation, error correction, gait events and pressure measurement system. It is developed to be cheap, low power, wireless, real time and suitable for real life in-door and out-door environment.

  14. 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.

  15. 49 CFR 232.217 - Train brake tests conducted using yard air.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Train brake tests conducted using yard air. 232... Train brake tests conducted using yard air. (a) When a train air brake system is tested from a yard air... reduction of brake pipe air pressure at the same, or slower, rate as an engineer's brake valve. (b) The...

  16. 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.

  17. 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

  18. 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).

  19. Plasma Braking Due to External Magnetic Perturbations

    Science.gov (United States)

    Frassinetti, L.; Olofsson, Kejo; Brunsell, P. R.; Khan, M. W. M.; Drake, J. R.

    2010-11-01

    The RFP EXTRAP T2R is equipped with a comprehensive active feedback system (128 active saddle coils in the full-coverage array) and active control of both resonant and non-resonant MHD modes has been demonstrated. The feedback algorithms, based on modern control methodology such as reference mode tracking (both amplitude and phase), are a useful tool to improve the ``state of the art'' of the MHD mode control. But this tool can be used also to improve the understanding and the characterization of other phenomena such as the ELM mitigation with a resonant magnetic perturbation or the plasma viscosity. The present work studies plasma and mode braking due to static RMPs. Results show that a static RMP produces a global braking of the flow profile. The study of the effect of RMPs characterized by different helicities will also give information on the plasma viscosity profile. Experimental results are finally compared to theoretical models.

  20. 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.

  1. 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...

  2. 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...

  3. 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 ...

  4. The effects of high custom made shoes on gait characteristics and patient satisfaction in hemiplegic gait

    NARCIS (Netherlands)

    Eckhardt, Martine M; Mulder, Mascha C Borgerhoff; Horemans, Herwin L; van der Woude, Lucas; Ribbers, Gerard M

    2011-01-01

    OBJECTIVE: To determine the effects of a temporary high custom made orthopaedic shoe on functional mobility, walking speed, and gait characteristics in hemiplegic stroke patients. In addition, interference of attentional demands and patient satisfaction were studied. DESIGN: Clinical experimental st

  5. The effects of high custom made shoes on gait characteristics and patient satisfaction in hemiplegic gait

    NARCIS (Netherlands)

    Eckhardt, Martine M.; Mulder, Mascha C. Borgerhoff; Horemans, Herwin L.; van der Woude, Luc H.; Ribbers, Gerard M.

    2011-01-01

    Objective: To determine the effects of a temporary high custom made orthopaedic shoe on functional mobility, walking speed, and gait characteristics in hemiplegic stroke patients. In addition, interference of attentional demands and patient satisfaction were studied. Design: Clinical experimental st

  6. Threshold Based Indexing of Commercial Shoe Print to Create Reference and Recovery Images

    CERN Document Server

    Rathinavel, S

    2010-01-01

    One of the important evidence in a crime scene that is normally overlooked but very important evidence is shoe print as the criminal is normally unaware of the mask for this. In this paper we use image processing technique to process reference shoe images to make it index-able for a search from the database the shoe print impressions available in the commercial market. This is achieved first by converting the commercially available image through the process of converting them to gray scale then apply image enhancement and restoration techniques and finally do image segmentation to store the segmented parameter as index in the database storage. We use histogram method for image enhancement, inverse filtering for image restoration and threshold method for indexing. We use global threshold as index of the shoe print. The paper describes this method and simulation results are included to validate the method.

  7. Use of orthopedic shoes in patients with degenerative disorders of the foot

    NARCIS (Netherlands)

    Jannink, Michiel J.; IJzerman, Maarten J.; Groothuis-Oudshoorn, Karin; Stewart, Roy E.; Groothoff, Johan W.; Lankhorst, Gustaaf J.

    2005-01-01

    Objectives: To study the actual use of orthopedic shoes by patients with degenerative foot disorders and to identify factors associated with use and nonuse, based on the parameters of the International Organization for Standardization definition of usability: effectiveness, efficiency, satisfaction,

  8. Injuries and Footwear (Part 1): Athletic Shoe History and Injuries in Relation to Foot Arch Height and Training in Boots.

    Science.gov (United States)

    Knapik, Joseph J; Pope, Rodney; Orr, Robin; Grier, Tyson

    2015-01-01

    This article traces the history of the athletic shoe, examines whether selecting running shoes based on foot arch height influences injuries, and examines historical data on injury rates when physical training (PT) is performed in boots versus running shoes. In the 1980s and into the 2000s, running shoe companies were advertising specialized shoes with "motion control," "stability," and "cushioning," designed for individuals with low, normal, and high arches, respectively. Despite marketing claims that these shoes would reduce injury rates, coordinated studies in Army, Air Force, and Marine Corps basic training showed that assigning or selecting shoes on this basis had no effect on injury rates. Consistent with this finding, biomechanical studies have shown that the relationships between arch height, foot joint mobility, and rear-foot motion are complex, variable, and frequently not as strong as often assumed. In 1982, the US Army switched from PT in boots to PT in running shoes because of the belief that boots were causing injuries and that running shoes would reduce injury rates. However, a historical comparison of injury rates before and after the switch to running shoes showed virtually no difference in injury risk between the two periods. It is not clear at this point if the type of footwear effects injury incidence.

  9. THE INFLUENCE OF COUNTRY IMAGE ON PRODUCT BRAND IN THEROMANIAN SHOES INDUSTRY

    OpenAIRE

    Carmen Adina Pastiu; Maria Mureșan

    2014-01-01

    ABSTRACT The current research study aims to analyze and identify the impact of the consumers‘perception on the brand image in the case of Romanian shoes products. The authors‘ goal wasthat of shaping a multifactor model which underlies the consumers‘ behavior on the brand imageof a product. The study also provides top management strands of the Romanian light industryenterprises. The research is based on a study conducted in Romania shoes products. Thequantitative research has been carried out...

  10. Adherence to wearing therapeutic shoes among people with diabetes: a systematic review and reflections

    OpenAIRE

    Jarl, Gustav; Lundqvist, Lars-Olov

    2016-01-01

    Gustav Jarl,1,2 Lars-Olov Lundqvist2 1Department of Prosthetics and Orthotics, Faculty of Medicine and Health, 2University Health Care Research Center, Faculty of Medicine and Health, Örebro University, Örebro, Sweden Introduction: Therapeutic shoes are prescribed to prevent diabetic foot ulcers, but adherence to wearing the shoes is often poor.  Aim: The aim of this study was to review the literature on factors that are associated with adherence to wearing therap...

  11. Surface effects on in-shoe plantar pressure and tibial impact during running

    OpenAIRE

    Weijie Fu; Ying Fang; David Ming Shuo Liu; Lin Wang; Sicong Ren; Yu Liu

    2015-01-01

    Purpose: This study aims to explore the effects of running on different surfaces on the characteristics of in-shoe plantar pressure and tibial acceleration. Methods: Thirteen male recreational runners were required to run at 12 km/h velocity on concrete, synthetic track, natural grass, a normal treadmill, and a treadmill equipped with an ethylene vinyl acetate (EVA) cushioning underlay (treadmill_EVA), respectively. An in-shoe plantar pressure system and an accelerometer attached to the ti...

  12. 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.

  13. Investigation of the coatings applied onto brake discs on disc-brake pad pair

    Directory of Open Access Journals (Sweden)

    I. Kiliçaslan

    2009-07-01

    Full Text Available While braking, according to the severity of it, thermal, metallurgical, constructive and tribological occurrences emerge on the brake disc-pad interface. In this study, NiCr was sprayed as bonding layer onto the discs, one ofwhich was coated with Al2O3-TiO2 by plasma spray and the other was coated with NiCr-Cr3C2 by High Velocity Oxygen Fuel (HVOF. In addition, the discs were tested with inertia dynamometer according to SAE’s J2522 testing procedure. The measurements showed that although the pads of the coated discs were exposed to higher braking temperatures, friction coefficient of the disc coated with NiCr- Cr3C2 was obtained 6 % higher compared to the original disc.

  14. 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.

  15. 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...

  16. 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...

  17. A case of contact dermatitis to dimethylfumarate in shoes identified in Italy

    Directory of Open Access Journals (Sweden)

    Franca Davanzo

    2010-12-01

    Full Text Available The present paper describes a case of shoe contact dermatitis from DMF identified by the Poison Control Centre of Milan (PCCM, Italy, in 2009. A 35 year old woman was affected by irritant reactions while wearing shoes contaminated with DMF. Exposure to these shoes was limited to a 8 hour period and was not repeated. In the following days the patient suffered feet blistering and swelling limited to the area in contact with shoe vamp. Topical application of cortisone did not prevent development of bullous eczema. After 20 days from exposure, the lesions were healed but the skin remained red, dry and very sensitive. Chemical analyses of shoes quantified an average concentration of DMF of 383 mg/kg. The patient refused to be patch tested. The observation here reported confirm that DMF should be considered a possible causal agent in shoe contact dermatitis. Documentation of cases exposed to this chemical provide a relevant support to characterize clinical manifestations and to identifying contaminated articles.

  18. Effects of a minimalist shoe on running economy and 5-km running performance.

    Science.gov (United States)

    Fuller, Joel T; Thewlis, Dominic; Tsiros, Margarita D; Brown, Nicholas A T; Buckley, Jonathan D

    2016-09-01

    The purpose of this study was to determine if minimalist shoes improve time trial performance of trained distance runners and if changes in running economy, shoe mass, stride length, stride rate and footfall pattern were related to any difference in performance. Twenty-six trained runners performed three 6-min sub-maximal treadmill runs at 11, 13 and 15 km·h(-1) in minimalist and conventional shoes while running economy, stride length, stride rate and footfall pattern were assessed. They then performed a 5-km time trial. In the minimalist shoe, runners completed the trial in less time (effect size 0.20 ± 0.12), were more economical during sub-maximal running (effect size 0.33 ± 0.14) and decreased stride length (effect size 0.22 ± 0.10) and increased stride rate (effect size 0.22 ± 0.11). All but one runner ran with a rearfoot footfall in the minimalist shoe. Improvements in time trial performance were associated with improvements in running economy at 15 km·h(-1) (r = 0.58), with 79% of the improved economy accounted for by reduced shoe mass (P performance. PMID:27328725

  19. Influence of shoes and heel strike on the loading of the hip joint.

    Science.gov (United States)

    Bergmann, G; Kniggendorf, H; Graichen, F; Rohlmann, A

    1995-07-01

    The forces and moments acting at the hip joint influence the long-term stability of the fixation of endoprostheses and the course of coxarthrosis. These loads may depend on the kind of footwear and the walking or running style. These factors were investigated in a patient with instrumented hip implants. He wore different sports shoes, normal leather shoes, hiking boots and clogs and walked barefoot with soft, normal and hard heel strikes. The loads were lowest while walking and jogging without shoes. All shoes increased the joint force and the bending moment at the implant slightly but the torsional moment rose by up to 50%. No relation was found between the different type of shoes and the load increase, only shoes with very hard soles were clearly disadvantageous. Soft heels, soles or insoles did not offer advantages. Gait stability seems to play the most important role in increasing the joint loading and should be the criterion for the choice of footwear. Smooth gait patterns with soft heel strikes are the only means to reduce joint loading during slow jogging. PMID:7657680

  20. Metallurgical Design and Development of NASA Crawler/Transporter Tread Belt Shoe Castings

    Science.gov (United States)

    Parker, Donald S.

    2006-01-01

    The NASA Crawler/Transporters (CT-1 and CT-2) used to transport the Space Shuffles are one of the largest tracked vehicles in existence today. Two of these machines have been used to move space flight vehicles at Kennedy Space Center since the Apollo missions of the 1960's and relatively few modifications have been made to keep them operational. In September of 2003 during normal Crawler/Transporter operations cracks were observed along the roller pad surfaces of several tread belt shoes. Further examination showed 20 cracked shoes on CT-1 and 40 cracked shoes on CT-2 and a formal failure analysis investigation was undertaken while the cracked shoes were replaced. Six shoes were cross-sectioned with the fracture surfaces exposed and it was determined that the cracks were due to fatigue that initiated on the internal casting web channels at pre-existing casting defects and propagated through thickness both transgranularly and intergranularly between internal shrinkage cavities, porosity, and along austenitic and ferritic grain boundaries. The original shoes were cast during the 1960's using a modified 861330 steel with slightly higher levels of chromium, nickel and molybdenum followed by heat treatment to achieve a minimum tensile strength of 11 Oksi. Subsequent metallurgical analysis of the tread belt shoes after multiple failures showed excessive internal defects, alloy segregation, a nonuniform ferritic/ bainitic/martensitic microstructure, and low average tensile properties indicative of poor casting and poor heat-treatment. As a result, NASA funded an initiative to replace all of the tread belt shoes on both crawler/transporters along with a redesign of the alloy, manufacturing, and heat-treatment to create a homogeneous cast structure with uniform mechanical and metallurgical properties. ME Global, a wholly owned subsidiary of ME Elecmetal based in Minneapolis, MN was selected as manufacturing and design partner to develop the new shoes and this paper

  1. Optical classification for quality and defect analysis of train brakes

    Science.gov (United States)

    Glock, Stefan; Hausmann, Stefan; Gerke, Sebastian; Warok, Alexander; Spiess, Peter; Witte, Stefan; Lohweg, Volker

    2009-06-01

    In this paper we present an optical measurement system approach for quality analysis of brakes which are used in high-speed trains. The brakes consist of the so called brake discs and pads. In a deceleration process the discs will be heated up to 500°C. The quality measure is based on the fact that the heated brake discs should not generate hot spots inside the brake material. Instead, the brake disc should be heated homogeneously by the deceleration. Therefore, it makes sense to analyze the number of hot spots and their relative gradients to create a quality measure for train brakes. In this contribution we present a new approach for a quality measurement system which is based on an image analysis and classification of infra-red based heat images. Brake images which are represented in pseudo-color are first transformed in a linear grayscale space by a hue-saturation-intensity (HSI) space. This transform is necessary for the following gradient analysis which is based on gray scale gradient filters. Furthermore, different features based on Haralick's measures are generated from the gray scale and gradient images. A following Fuzzy-Pattern-Classifier is used for the classification of good and bad brakes. It has to be pointed out that the classifier returns a score value for each brake which is between 0 and 100% good quality. This fact guarantees that not only good and bad bakes can be distinguished, but also their quality can be labeled. The results show that all critical thermal patterns of train brakes can be sensed and verified.

  2. LOW HANDICAP GOLFERS GENERATE MORE TORQUE AT THE SHOE-NATURAL GRASS INTERFACE WHEN USING A DRIVER

    Directory of Open Access Journals (Sweden)

    Paul Worsfold

    2008-09-01

    Full Text Available The aim was to determine the rotational torque occurring at the shoe-natural grass interface during golf swing performance with different clubs, and to determine the influence of handicap and golf shoe design. Twenty-four golfers (8 low 0-7; 8 medium 8-14; and 8 high 15+ performed 5 shots with a driver, 3-iron and 7-iron when 3 shoes were worn: a modern 8 mm metal 7-spike shoe, an alternative 7-spike shoe and a flat soled shoe. Torque was measured at the front and back foot by grass covered force platforms in an outdoor field. Torque at the shoe- natural turf interface was similar at the front foot when using a driver, 3-iron and 7-iron with maximum mean torque (Tzmax 17-19 Nm and torque generation in the entire backswing and downswing approximately 40 Nm. At the back foot, torque was less than at the front foot when using the driver, 3-iron and 7-iron. At the back foot Tzmax was 6-7 Nm, and torque generation was 10-16 Nm, with a trend for greater torque generation when using the driver rather than the irons. The metal spike shoe allowed significantly more back foot torque generation when using a driver than a flat- soled shoe (p 0.05, although back foot mean torques generated tended to be greater for the metal spike shoe. The golf shot outcomes were similar for low, medium and high handicappers in both metal and alternative spike shoes (metal: 87%; 76%; 54%; alternative: 85%; 74%; 54% respectively. The better, low handicap golfers generated significantly more back foot torque (metal spike: 18.2 Nm; alternative: 15.8 Nm; p < 0.05 when using a driver. Further research should consider back foot shoe-grass interface demands during driver usage by low handicap and lighter body-weight golfers

  3. Detection of abnormalities in a human gait using smart shoes

    Science.gov (United States)

    Kong, Kyoungchul; Bae, Joonbum; Tomizuka, Masayoshi

    2008-03-01

    Health monitoring systems require a means for detecting and quantifying abnormalities from measured signals. In this paper, a new method for detecting abnormalities in a human gait is proposed for an improved gait monitoring system for patients with walking problems. In the previous work, we introduced a fuzzy logic algorithm for detecting phases in a human gait based on four foot pressure sensors for each of the right and left foot. The fuzzy logic algorithm detects the gait phases smoothly and continuously, and retains all information obtained from sensors. In this paper, a higher level algorithm for detecting abnormalities in the gait phases obtained from the fuzzy logic is discussed. In the proposed algorithm, two major abnormalities are detected 1) when the sensors measure improper foot pressure patterns, and 2) when the human does not follow a natural sequence of gait phases. For mathematical realization of the algorithm, the gait phases are dealt with by a vector analysis method. The proposed detection algorithm is verified by experiments on abnormal gaits as well as normal gaits. The experiment makes use of the Smart Shoes that embeds four bladders filled with air, the pressure changes in which are detected by pressure transducers.

  4. [Health effects of occupational exposure among shoe workers. A review].

    Science.gov (United States)

    Szadkowska-Stańczyk, Irena; Woźniak, Helena; Stroszejn-Mrowca, Grazyna

    2003-01-01

    World-wide epidemiological studies provide evidence that the employment in the shoe production and repair plants is associated with an enhanced risk for cancer (primarily nose and nasal sinuses). According to the majority of authors, it is induced by exposure to leather dust. It is also known that, leather dust particles contain numerous chemicals acquired during the process of leather tanning and finishing (chromium salts, vegetable dye extracts, mineral oils). Some of these compounds exert carcinogenic effect. This paper provides a review of the results of epidemiological studies on health effects of exposure to harmful factors present mainly at the footwear production and repair. These results reveal an enhanced risk for cancer of nose or nasal sinuses induced by leather dust, as well as neoplasms of hematopoietic and lymphatic systems, resulting from exposure to solvents (mostly benzene). Among non-neoplasms, diseases of the musculoskeletal system associated with ergonomic factors, contact dermatics, chronic pulmonary diseases and damage of peripheral nerves in solvent-exposed workers are diagnosed. PMID:12731407

  5. High- versus low-top shoes for the prevention of ankle sprains in basketball players. A prospective randomized study.

    Science.gov (United States)

    Barrett, J R; Tanji, J L; Drake, C; Fuller, D; Kawasaki, R I; Fenton, R M

    1993-01-01

    Using a prospective, randomized experimental design, 622 college intramural basketball players were stratified by a previous history of ankle sprains to wear a new pair of either high-top, high-top with inflatable air chambers, or low-top basketball shoes during all games for a complete season. Subjects were asked to complete a history questionnaire and were given a complete ankle examination. They were allowed to wear these shoes only during basketball competition. Followed over the course of a 2-month intramural season, 15 ankle injuries occurred during 39,302 minutes of player-time: 7 in high-top shoes, 4 in low-top shoes, and 4 in high-top shoes with inflatable air chambers. The injury rates (injuries per player-minute) were 4.80 x 10(-4) in high-top shoes, 4.06 x 10(-4) in low-top shoes, and 2.69 x 10(-4) in high-top shoes with inflatable air chambers. There was no significant difference among these 3 groups, leading to the conclusion that there is no strong relationship between shoe type and ankle sprains. PMID:8368420

  6. 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.

  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. THE THEORETICAL MODEL FOR PREDICTING CIRCULATION VELOCITY OF HYDRAULIC BRAKE

    Institute of Scientific and Technical Information of China (English)

    刘英林; 侯春生

    1997-01-01

    By rational hypothesis of fluid flow pattern, applied the law of conservation of energy and integrated the laboratory test results, finished the prediction by the theoretical model of circulation velocity of hydraulic brake which is important parameter. Thus provide the theoritical basis for hydraulic brake of belt conveyor whose research has just been started.

  9. Braking system for use with an arbor of a microscope

    Science.gov (United States)

    Norgren, Duane U.

    1984-01-01

    A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling device causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

  10. 49 CFR 393.48 - Brakes to be operative.

    Science.gov (United States)

    2010-10-01

    ...) The steering axle of a three-axle dolly which is steered by a co-driver; (5) Loaded house moving... times be capable of operating. (b) Devices to reduce or remove front-wheel braking effort. A commercial motor vehicle may be equipped with a device to reduce the front wheel braking effort (or in the case...

  11. 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.

  12. 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.

  13. Design optimization of a magnetorheological brake in powered knee orthosis

    Science.gov (United States)

    Ma, Hao; Liao, Wei-Hsin

    2015-04-01

    Magneto-rheological (MR) fluids have been utilized in devices like orthoses and prostheses to generate controllable braking torque. In this paper, a flat shape rotary MR brake is designed for powered knee orthosis to provide adjustable resistance. Multiple disk structure with interior inner coil is adopted in the MR brake configuration. In order to increase the maximal magnetic flux, a novel internal structure design with smooth transition surface is proposed. Based on this design, a parameterized model of the MR brake is built for geometrical optimization. Multiple factors are considered in the optimization objective: braking torque, weight, and, particularly, average power consumption. The optimization is then performed with Finite Element Analysis (FEA), and the optimal design is obtained among the Pareto-optimal set considering the trade-offs in design objectives.

  14. Parity space-based fault diagnosis of CCBII braking system

    Institute of Scientific and Technical Information of China (English)

    黄志武; 杨迎泽; 王晶; 李赟

    2013-01-01

    Fault diagnosis is a key issue of the CCBII(computer controlled brake II) braking system, because the CCBII braking system is very complicated and nonlinear, which may exhibit isolated and multi-component coupled faults. A parity space-based method was proposed for fault diagnosis of CCBII braking systems. Firstly, the mathematical models were established according to three function modules of CCBII braking systems where the air fluid theory was utilized. Then, parity vector and threshold function were designed for each output of the system so as to identify more system faults. Fault character matrix was built based on the causal relationship between the output and the fault according to the system function and internal structure. Finally, fault detection and isolation can be realized by the comparison of the observed system output and the fault character matrix. Simulation results show that the proposed method is entirely feasible and effective.

  15. 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.

  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. Multibody Dynamic Stress Simulation of Rigid-Flexible Shovel Crawler Shoes

    Directory of Open Access Journals (Sweden)

    Samuel Frimpong

    2016-06-01

    Full Text Available Electric shovels are used in surface mining operations to achieve economic production capacities. The capital investments and operating costs associated with the shovels deployed in the Athabasca oil sands formation are high due to the abrasive conditions. The shovel crawler shoes interact with sharp and abrasive sand particles, and, thus, are subjected to high transient dynamic stresses. These high stresses cause wear and tear leading to crack initiation, propagation and premature fatigue failure. The objective of this paper is to develop a model to characterize the crawler stresses and deformation for the P&H 4100C BOSS during propel and loading using rigid-flexible multi-body dynamic theory. A 3-D virtual prototype model of the rigid-flexible crawler track assembly and its interactions with oil sand formation is simulated to capture the model dynamics within multibody dynamics software MSC ADAMS. The modal and stress shapes and modal loads due to machine weight for each flexible crawler shoes are generated from finite element analysis (FEA. The modal coordinates from the simulation are combined with mode and stress shapes using modal superposition method to calculate real-time stresses and deformation of flexible crawler shoes. The results show a maximum von Mises stress value of 170 MPa occurring in the driving crawler shoe during the propel motion. This study provides a foundation for the subsequent fatigue life analysis of crawler shoes for extending crawler service life.

  18. In-shoe loading in rearfoot and non-rearfoot strikers during running using minimalist footwear.

    Science.gov (United States)

    Kernozek, T W; Meardon, S; Vannatta, C N

    2014-12-01

    Recent trends promote a "barefoot" running style to reduce injury. "Minimalist" shoes are designed to mimic the barefoot running with some foot protection. However, it is unknown how "minimalist" shoes alter plantar loading. Our purpose was to compare plantar loads between rearfoot strikers and non-rearfoot strikers after 4 weeks of running in minimalist footwear. 30 females were provided Vibram(®) Bikila shoes and instructed to gradually transition to running in these shoes. Plantar loading was measured using an in-shoe pressure sensor after the 4 weeks. Multivariate analysis was performed to detect differences in loading between rearfoot and non-rearfoot strikers in different plantar regions. Differences in plantar loading occurred between foot strike patterns running in minimalist footwear. Pressure and force variables were greater in the metatarsals and lower in the heel region in non-rearfoot strikers. Peak pressure for the whole foot was greater in non-rearfoot strikers while no difference was observed in maximum force or contact time for the whole foot between strike types. Allowing time for accommodation and adaptation to different stresses on the foot may be warranted when using minimalist footwear depending on foot strike pattern of the -runner.

  19. Technical evaluation of a CAD system for orthopaedic shoe-upper design.

    Science.gov (United States)

    Lord, M; Foulston, J; Smith, P J

    1991-01-01

    Computer aided design is now employed routinely in the volume shoe trade. New styles are developed on a three-dimensional image of the last followed by automated pattern generation and engineering. It is suggested that such systems could be useful in the orthopaedic footwear industry although the different requirements for these bespoke products need careful consideration. A clinical trial has been conducted on the Shoemaster (Clarks Shoes) upper design system both to assess its technical capabilities and to consider its role in improvement of service and cosmetic appearance. This particular system works throughout on a three-dimensional representation of the shoe last, which offers particular advantages for integration with shape capture and reproduction. The report concentrates on the technical evaluation to assess (a) its ability to work with unusual last shapes dictated by medical requirements and (b) its potential for integration into a complete computer system for design of both shoe lasts and shoe uppers. The trial indicates that this particular system is promising in both respects.

  20. Technical evaluation of a CAD system for orthopaedic shoe-upper design.

    Science.gov (United States)

    Lord, M; Foulston, J; Smith, P J

    1991-01-01

    Computer aided design is now employed routinely in the volume shoe trade. New styles are developed on a three-dimensional image of the last followed by automated pattern generation and engineering. It is suggested that such systems could be useful in the orthopaedic footwear industry although the different requirements for these bespoke products need careful consideration. A clinical trial has been conducted on the Shoemaster (Clarks Shoes) upper design system both to assess its technical capabilities and to consider its role in improvement of service and cosmetic appearance. This particular system works throughout on a three-dimensional representation of the shoe last, which offers particular advantages for integration with shape capture and reproduction. The report concentrates on the technical evaluation to assess (a) its ability to work with unusual last shapes dictated by medical requirements and (b) its potential for integration into a complete computer system for design of both shoe lasts and shoe uppers. The trial indicates that this particular system is promising in both respects. PMID:1840716

  1. Basketball shoe height and the maximal muscular resistance to applied ankle inversion and eversion moments.

    Science.gov (United States)

    Ottaviani, R A; Ashton-Miller, J A; Kothari, S U; Wojtys, E M

    1995-01-01

    To determine if the height of a basketball shoe alters the maximal inversion and eversion moment that can be actively resisted by the ankle in the frontal plane, we tested 20 healthy, young adult men with no recent ankle injuries. Subjects underwent unipedal functional ankle strength testing under weightbearing conditions at 0 degrees, 16 degrees, and 32 degrees of ankle plantar flexion using a specially designed testing apparatus. Testing was performed with the subject wearing either a low- or a three quarter-top basketball shoe. Shoe height did not significantly affect an individual's ability to actively resist an eversion moment at any angle of ankle plantar flexion. However, tests at 0 degrees of ankle plantar flexion demonstrated that the three quarter-top basketball shoe we tested significantly increased the maximal resistance to an inversion moment by 29.4%. At 16 degrees of ankle plantar flexion, inversion resistance was also significantly improved by 20.4%. These results show that athletic shoe height can significantly increase the active resistance to an inversion moment in moderate ankle plantar flexion. The findings apply to a neutral foot position in the frontal plane, an orientation equivalent to the early phase of a potential ankle sprain. PMID:7573650

  2. Comparison of shoe-length fit between people with and without diabetic peripheral neuropathy: a case–control study

    Directory of Open Access Journals (Sweden)

    McInnes Alistair D

    2012-04-01

    Full Text Available Abstract Background Amongst the many identified mechanisms leading to diabetic foot ulceration, ill-fitting footwear is one. There is anecdotal evidence that people with diabetic peripheral neuropathy wear shoes that are too small in order to increase the sensation of fit. The aim of this study was to determine whether people with diabetic sensory neuropathy wear appropriate length footwear. Methods A case–control design was used to compare internal shoe length and foot length differences between a group of people with diabetes and peripheral sensory neuropathy and a group of people without diabetes and no peripheral sensory neuropathy. Shoe and foot length measurements were taken using a calibrated Internal Shoe Size Gauge® and a Brannock Device®, respectively. Results Data was collected from 85 participants with diabetes and 118 participants without diabetes. The mean difference between shoe and foot length was not significantly different between the two groups. However, a significant number of participants within both groups had a shoe to foot length difference that lay outside a previously suggested 10 to 15 mm range. From the diabetic and non-diabetic groups 82% (70/85 and 66% (78/118, respectively had a foot to shoe length difference outside this same range. Conclusions This study shows that although there is no significant difference in shoe-length fit between participants with and without neuropathy, a significant proportion of these populations wear shoes that are either too long or too short for their foot length according to the 10 to 15 mm value used for comparison. The study has highlighted the need for standardised approaches when considering the allowance required between foot and internal shoe length and for the measurement and comparison of foot and shoe dimensions.

  3. Design and Analysis of Electro-mechanical Hybrid Anti-lock Braking System for Hybrid Electric Vehicle Utilizing Motor Regenerative Braking

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jianlong; YIN Chengliang; ZHANG Jianwu

    2009-01-01

    Braking on low adhesion-coefficient roads, hybrid electric vehicle's motor regenerative torque is switched off to safeguard the normal anti-lock braking system (ABS) function. When the ABS control is terminated, the motor regenerative braking is readmitted.Aiming at avoiding permanent cycles from hydraulic anti-lock braking to motor regenerative braking, a novel electro-mechanical hybrid anti-lock braking system using fuzzy logic is designed. Different from the traditional single control structure, this system has a two-layered hierarchical structure. The first layer is responsible for harmonious adjustment or interaction between regenerative system and anti-lock braking system. The second layer is responsible for braking torque distribution and adjustment. The closed-loop simulation model is built. Control strategy and method for coordination between regenerative and anti-lock braking are developed. Simulation braking on low adhesion-coefficient roads with fuzzy logic control and real vehicle braking field test are presented. The results from simulating analysis and experiment show braking performance of the vehicle is perfect, harmonious coordination between regenerative and anti-lock braking function, significant amount of braking energy can be recovered and the proposed control strategy and method are effective.

  4. 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...

  5. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.

    Science.gov (United States)

    2010-10-01

    ... systems. S1. Scope. This standard specifies requirements for hydraulic and electric service brake systems... braking performance under normal and emergency conditions. S3. Application. This standard applies to multi... are equipped with hydraulic or electric brake systems. S4. Definitions. Antilock brake system or...

  6. 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.

  7. Design and development of human factors based shoe midsole using additive manufacturing

    Directory of Open Access Journals (Sweden)

    D. Rambabu

    2014-03-01

    Full Text Available The objective of this research is to design and prototype a shoe midsole which bears enough weight of the wearer and absorbs impact forces, at same time being light weight on the aspect of material used and design. The whole design is based on human factors and requirements which were studied using a survey among a group, based on product development guidelines as a part of product lifecycle management. The design conceptualizes the use of gas as the weight bearer and impact absorber by being compactly pressurized in separate pockets, the pockets are intricately placed to optimize force absorption and maintain stability. The prototype is build using additive manufacturing technique which enabled to design with complexity. Thus a highly comfortable and ergonomically better shoe sole design was achieved; this helped in meeting the customer requirements.   Keywords: Shoe Midsole; Human Factors Based Design; Prototyping; Additive Manufacturing.

  8. DEVELOPMENT AND REPRODUCIBILITY OF A SHORT QUESTIONNAIRE TO MEASURE USE AND USABILITY OF CUSTOM-MADE ORTHOPAEDIC SHOES

    NARCIS (Netherlands)

    van Netten, Jaap J.; Hijmans, Juha M.; Jannink, Michiel J. A.; Geertzen, Jan H. B.; Postema, Klaas

    2009-01-01

    Objective:To develop it short and easy to use questionnaire to measure use and usability of custom-made orthopaedic shoes, and to investigate its reproducibility. Design: Development of the questionnaire (Monitor Orthopaedic Shoes) was based on a literature search. expert interviews. 2 expert meetin

  9. Development and reproducibility of a short questionnaire to measure use and usability of custom-made orthopaedic shoes

    NARCIS (Netherlands)

    Netten, van Jaap J.; Hijmans, Juha M.; Jannink, Michiel J.A.; Geertzen, Jan H.B.; Postema, Klaas

    2009-01-01

    Objective: To develop a short and easy to use questionnaire to measure use and usability of custom-made orthopaedic shoes, and to investigate its reproducibility. Design: Development of the questionnaire (Monitor Orthopaedic Shoes) was based on a literature search, expert interviews, 2 expert meetin

  10. Differences in plantar loading between training shoes and racing flats at a self-selected running speed

    NARCIS (Netherlands)

    J.I. Wiegerinck; J. Boyd; J.C. Yoder; A.N. Abbey; J.A. Nunley; R.M. Queen

    2009-01-01

    The purpose of this study was to examine the difference in plantar loading between two different running shoe types. We hypothesized that a higher maximum force, peak pressure, and contact area would exist beneath the entire foot while running in a racing flat when compared to a training shoe. 37 at

  11. The Relationship of Foot Strike Pattern, Shoe Type, and Performance in a 50-km Trail Race.

    Science.gov (United States)

    Kasmer, Mark E; Liu, Xue-Cheng; Roberts, Kyle G; Valadao, Jason M

    2016-06-01

    Kasmer, ME, Liu, X-c, Roberts, KG, and Valadao, JM. Relationship of foot strike pattern, shoe type, and performance in a 50-km trail race. J Strength Cond Res 30(6): 1633-1637, 2016-Recent "in-race" studies have observed the foot strike patterns of runners in traditional road marathon races. However, similar studies have not been conducted for trail runners, which have been estimated to account for 11% of all runners. The purpose of this study was to (a) determine the rear-foot strike (RFS) prevalence in a 50-km trail race and compare with traditional road marathon races; (b) determine if there is a relationship between foot strike and sex in a 50-km trail race; and (c) determine if there is a relationship between foot strike, shoe type, and performance in a 50-km trail race. One hundred sixty-five runners were videotaped at the 8.1-km mark of the 2012 Ice Age Trail 50-km race. Foot strike analysis revealed RFS prevalence of 85.1%, less than previously reported in traditional road marathon races. There was no relationship found between sex and foot strike (p = 0.60). A significant effect of shoe type on foot strike (RFS was less common among runners in minimalist shoes, p < 0.01) and performance (faster runners were more likely to be wearing minimalist shoes, p < 0.01) was observed; however, no association between foot strike and performance was observed (p = 0.83). This study suggests that most trail runners, albeit less than road runners, prefer an RFS pattern, which is accompanied by biomechanical consequences unique from a non-RFS pattern and, therefore, likely carries a unique injury profile. In addition, the findings in this study suggest that minimalist shoes may represent a reasonable training modification to improve performance. PMID:23860289

  12. Regenerative braking control strategy in mild hybrid electric vehicles equipped with automatic manual transmission

    Institute of Scientific and Technical Information of China (English)

    QIN Datong; YE Ming; LIU Zhenjun

    2007-01-01

    The actual regenerative braking force of an integrated starter/generator (ISG),which is varied with desired braking deceleration and vehicle speed,is calculated based on an analysis of the required deceleration,maximum braking force of ISG,engine braking force and state of charge (SOC) of battery.Braking force distribution strategies are presented according to the actual regenerative braking force of ISG.To recover the vehicle's kinetic energy maximally,braking shift rules for a mild hybrid electric vehicle (HEV) equipped with automatic manual transmission (AMT) are brought forward and effects of transmission ratios are considered.A test-bed is built up and regenerative braking tests are carried out.The results show that power recovered by the braking shift rules is more than that recovered by the normal braking control rules.

  13. 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.

  14. 矿井摩擦式提升机制动装置在线监测系统设计%Design of an on-line monitoring system for brakes of mine friction hoists

    Institute of Scientific and Technical Information of China (English)

    姬程鹏; 张晓光; 毕伟; 卓蒙蒙

    2011-01-01

    根据国内现有矿井提升机特点,结合现代监测与诊断技术,设计开发了一种用于矿井摩擦式提升机制动装置的在线监测系统.介绍了系统构成、参数采集方案和故障诊断策略,并提出了利用制动减速度测量闸瓦摩擦系数的方法.试验表明,该系统性能良好,是提高提升机安全性、可靠性的一种行之有效的方法.%According to the characteristics of existing domestic mine hoists, an on-line monitoring system for the brake of the mine friction hoist is developed based on modem monitoring and diagnosis technology.The system structure, parameter acquisition scheme and fault diagnosis strategy are introduced, and a method of measuring the friction coefficient of the brake shoe by using braking deceleration is presented.The test indicates that the system has good performance, and is an effective way to improve security and reliability of the hoist.

  15. Effect of children's shoes on gait: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Burns Joshua

    2011-01-01

    Full Text Available Abstract Background The effect of footwear on the gait of children is poorly understood. This systematic review synthesises the evidence of the biomechanical effects of shoes on children during walking and running. Methods Study inclusion criteria were: barefoot and shod conditions; healthy children aged ≤ 16 years; sample size of n > 1. Novelty footwear was excluded. Studies were located by online database-searching, hand-searching and contact with experts. Two authors selected studies and assessed study methodology using the Quality Index. Meta-analysis of continuous variables for homogeneous studies was undertaken using the inverse variance approach. Significance level was set at P 2. Where I2 > 25%, a random-effects model analysis was used and where I2 Results Eleven studies were included. Sample size ranged from 4-898. Median Quality Index was 20/32 (range 11-27. Five studies randomised shoe order, six studies standardised footwear. Shod walking increased: velocity, step length, step time, base of support, double-support time, stance time, time to toe-off, sagittal tibia-rearfoot range of motion (ROM, sagittal tibia-foot ROM, ankle max-plantarflexion, Ankle ROM, foot lift to max-plantarflexion, 'subtalar' rotation ROM, knee sagittal ROM and tibialis anterior activity. Shod walking decreased: cadence, single-support time, ankle max-dorsiflexion, ankle at foot-lift, hallux ROM, arch length change, foot torsion, forefoot supination, forefoot width and midfoot ROM in all planes. Shod running decreased: long axis maximum tibial-acceleration, shock-wave transmission as a ratio of maximum tibial-acceleration, ankle plantarflexion at foot strike, knee angular velocity and tibial swing velocity. No variables increased during shod running. Conclusions Shoes affect the gait of children. With shoes, children walk faster by taking longer steps with greater ankle and knee motion and increased tibialis anterior activity. Shoes reduce foot motion and

  16. Water, energy and carbon footprints of a pair of leather shoes

    OpenAIRE

    Rivera Muñoz, Zayetzi

    2013-01-01

    The shoe market is very big and complex. It is not easy for the consumer to know or estimate the true value of a product´s features and the environmental impact it has. The aim of this study is to analyze and improve a pair of leather shoes, including materials selection and end of life strategies to lower environmental pressure due to water and energy use and CO2 equivalent emissions. The present study was divided into two main stages: In the first stage a literature survey on the footwear i...

  17. Exploiting Fashion Features for Floor Storage Systems in the Shoe Industry

    Directory of Open Access Journals (Sweden)

    Antonella Meneghetti

    2013-08-01

    Full Text Available Floor storage systems are used in the shoe industry to store fashion products of seasonal collections of low quantity and high variety. Since space is valuable and order picking must be sped up, stacking of shoeboxes should be optimized. The problem is modelled based on shoe features (model, type, colour, and size and with the goal of forcing similar boxes into locations close to each other in order to improve workers’ ability to retrieve orders fast. The model is encoded in Constraint Logic Programming and solved comparing different strategies, also using Large Neighbourhood Search. Simulation experiments are run to evaluate how the stacking model affects picking performance.

  18. On the interaction between structure and oil film of a guide shoe bearing

    DEFF Research Database (Denmark)

    Vølund, Anders

    2001-01-01

    A solution procedure for the determination of the oil film thickness of a guide shoe bearing for a large two stroke marine diesel engine is presented. Based on a previous study considering oil film thickness of a guide shoe bearing with rigid structural parts a model for the interaction between...... structure and oil film is implemented. The model takes into account the elastic deformation of the bearing parts. An iterative procedure for determining pressure, deformation and squeeze velocity is applied. The results are compared to a traditional calculation of rigid components. The model...

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

    Energy Technology Data Exchange (ETDEWEB)

    Ripley, Maurice I. [Australian Nuclear Scinece and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia)]. E-mail: m.ripley@ansto.gov.au; Kirstein, Oliver [Australian Nuclear Scinece and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia)

    2006-11-15

    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.

  20. 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.

  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. 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.

  3. 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

  4. CARS WEAVE IN THE BRAKING POSITION OF A HUMP

    Directory of Open Access Journals (Sweden)

    D. O. Serheiev

    2009-09-01

    Full Text Available The work contains a theoretical study of freight car vibrations while a group of the freight cars are under braking by retarder. The purpose is to discover possible causes of derailment. The corresponding analytical description is presented. The solution of the differential equations for the groups of carriages confirms an assumption, according to which a contact between the carriage wheel of and the rail can be lost due to the oscillations induced by braking. The results allow to present recommendation for choosing the safe regime of braking in order to avoid the derailment.

  5. 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.

  6. 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

  7. Tribomaterial factors in space mechanism brake performance

    Science.gov (United States)

    Hawthorne, H. M.

    1990-01-01

    The asbestos/phenolic pads of Shuttle Remote Manipulator System (SRMS) brakes are unsuitable for use in long life space mechanisms because their friction decreases on extended sliding in high vacuum. Dehydration of the material and accumulation of wear debris in the conforming interface of this tribosystem induces the permanent friction changes. Other polymer and some ceramic based materials exhibit similar frictional torque behavior due to the development of minimal contact patches by the interfacial debris. In contrast, high friction occurs when other ceramics form many small contacts throughout fine debris beds. Generating this latter interfacial structure during run-in ensures that the in-vacuo friction remains stable thereafter. Such materials with low wear rates are potential candidates for friction elements in SSRMS and similar mechanisms.

  8. 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

  9. Linear Control Technique for Anti-Lock Braking System

    Directory of Open Access Journals (Sweden)

    Chankit Jain

    2014-08-01

    Full Text Available Antilock braking systems are used in modern cars to prevent the wheels from locking after brakes are applied. The dynamics of the controller needed for antilock braking system depends on various factors. The vehicle model often is in nonlinear form. Controller needs to provide a controlled torque necessary to maintain optimum value of the wheel slip ratio. The slip ratio is represented in terms of vehicle speed and wheel rotation. In present work first of all system dynamic equations are explained and a slip ratio is expressed in terms of system variables namely vehicle linear velocity and angular velocity of the wheel. By applying a bias braking force system, response is obtained using Simulink models. Using the linear control strategies like PI-type the effectiveness of maintaining desired slip ratio is tested. It is always observed that a steady state error of 10% occurring in all the control system models.

  10. 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

  11. 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....

  12. Modelling of friction-induced brake oscillations; Modellbildung reibungsselbsterregter Bremsenschwingungen

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, M.; Popp, K. [Hannover Univ. (Germany). Inst. fuer Mechanik

    2001-07-01

    Oscillatory mechanisms describing the energy transfer from the brake disk into the mechanical brake system are described and discussed, and an extended model of a real brake is presented. It is a multi-element system which takes account of elastic modes of the brake components. Components with high relevance for the initiation of oscillations are identified on the basis of a sensitivity analysis of the linear model. [German] Es werden Erregungs-Mechanismen (fallende Reibkennlinie, geometrische Instabilitaet, nichtkonservative Lagekraefte) zur Beschreibung des Energieeintrages von der Bremsscheibe in das mechanische System Bremse dargelegt und diskutiert. Darauf aufbauend wird ein erweitertes Prinzipmodell vorgestellt, das eine reale Schwimmsattelbremse beschreibt. Dabei handelt es sich um ein Mehrkoerpersystem, das elastische Moden der Bremsenbauteile beruecksichtigt. Anhand einer Sensitivitaets-Analyse des linearen Modells werden Bauteile mit hoher Relevanz fuer die Schwingungsanregung identifiziert. (orig.)

  13. 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.

  14. 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...

  15. 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 long-term vision and specific guidance on managing habitats for the resources of concern...

  16. 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...

  17. 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.

  18. 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...

  19. 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...

  20. 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...

  1. Crayfish survey at Morgan Brake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Crayfish sampling on Morgan Brake NWR for vernal crawfish and other species was done for 3 days at five sites. Data are present on species of crawfish and...

  2. 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...

  3. 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...

  4. 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.

  5. 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.

  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. 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.

  8. 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.

  9. Infrared characterization of thermal gradients on disc brakes

    Science.gov (United States)

    Panier, Stephane; Dufrenoy, Philippe; Bremond, Pierre

    2003-04-01

    The heat generated in frictional organs like brakes and clutches induces thermal distortions which may lead to localized contact areas and hot spots developments. Hot spots are high thermal gradients on the rubbing surface. They count among the most dangerous phenomena in frictional organs leading to damage, early failure and unacceptable braking performances such as brake fade or undesirable low frequency vibrations called hot judder. In this paper, an experimental study of hot spots occurrence in railway disc brakes is reported on. The aim of this study was to better classify and to explain the thermal gradients appearance on the surface of the disc. Thermograph measurements with an infrared camera have been carried out on the rubbing surface of brake discs on a full-scale test bench. The infrared system was set to take temperature readings in snap shot mode precisely synchronized with the rotation of the disc. Very short integration time allows reducing drastically haziness of thermal images. Based on thermographs, a classification of hot-spots observed in disc brakes is proposed. A detailed investigation of the most damaging thermal gradients, called macroscopic hot spots (MHS) is given. From these experimental researches, a scenario of hot spots occurrence is suggested step by step. Thanks to infrared measurements at high frequency with high resolution, observations give new highlights on the conditions of hot spots appearance. Comparison of the experimental observations with the theoretical approaches is finally discussed.

  10. A Novel Method for Measuring In-Shoe Navicular Drop during Gait

    Directory of Open Access Journals (Sweden)

    Henrik Karstoft

    2012-08-01

    Full Text Available Analysis of foot movement is essential in the treatment and prevention of foot-related disorders. Measuring the in-shoe foot movement during everyday activities, such as sports, has the potential to become an important diagnostic tool in clinical practice. The current paper describes the development of a thin, flexible and robust capacitive strain sensor for the in-shoe measurement of the navicular drop. The navicular drop is a well-recognized measure of foot movement. The position of the strain sensor on the foot was analyzed to determine the optimal points of attachment. The sensor was evaluated against a state-of-the-art video-based system that tracks reflective markers on the bare foot. Preliminary experimental results show that the developed strain sensor is able to measure navicular drop on the bare foot with an accuracy on par with the video-based system and with a high reproducibility. Temporal comparison of video-based, barefoot and in-shoe measurements indicate that the developed sensor measures the navicular drop accurately in shoes and can be used without any discomfort for the user.

  11. What influences a patient's decision to use custom-made orthopaedic shoes?

    NARCIS (Netherlands)

    van Netten, Jaap J.; Dijkstra, Pieter U.; Geertzen, Jan H. B.; Postema, Klaas

    2012-01-01

    Background: Despite potential benefits, some patients decide not to use their custom-made orthopaedic shoes (OS). Factors are known in the domains 'usability', 'communication and service', and 'opinion of others' that influence a patient's decision to use OS. However, the interplay between these fac

  12. Modified distal shoe appliance for premature loss of multiple deciduous molars: a case report.

    Science.gov (United States)

    Bhat, Prasanna Kumar; K, Navin H; Idris, Mohammed; Christopher, Pradeep; Rai, Niharika

    2014-08-01

    Preservation of the primary dentition until the normal time of exfoliation is one of the most important factor involved in preventive and interceptive dentistry. The premature loss of second primary molar before the eruption of permanent first molar can create a significant arch space/tooth size discrepancy. Distal shoe space maintainer is a valuable part of the Paediatric Dentist's armamentarium in those cases where the second primary molar is prematurely lost and it helps to guide the first permanent molar into place. Conventional design poses various limitations in cases of premature loss of multiple deciduous molars. Thus, it is required to modify the conventional designs according to the needs of the patient. This case report describes an innovative modification of distal shoe appliance in cases of premature loss of multiple deciduous molars. In the present case, modification of distal shoe space maintainer was advocated because of inadequate abutments caused due to multiple loss of deciduous molars. Bilateral design of distal shoe was planned for unilateral loss of deciduous molars.

  13. The strategic capability of a shoe company from Brazil: the Olympikus case

    Directory of Open Access Journals (Sweden)

    Juliana Suzin

    2007-01-01

    Full Text Available The main objective in this article is to analyze how the opportunities and resources are identified and mobilized to assure conditions to a traditional industry to compete through innovation. In this study decisions and actions associated to enterprising and innovations are analyzed in the context of the traditional Brazilian Industry. In this context, the global production chains are evaluated, in particular, the behavior and performance of the Brazilian Shoe Industry. The study of one case of the shoe industry provides the empiric base to discuss the questions proposed. The analysis of one line from articles produced by Calçados Azaléia, one of the biggest shoe factories in Brazil, is made. The evidences are based on interviews proposed to the executives of the company in the years of 2005 and 2006 where secondary data helps to analyze the subject, shoe business sector and the company. The conclusion is that the case takes a ‘revolutionary’ perspective of competitiveness, through the launching of one product that allies technology, quality and design, assuming a new level on administrative innovation and a new strategic position at the dynamic value chain.

  14. Fecundity of the Indian Horse-shoe crab, Carcinoscorpius rotundicauda (Latreille)

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Parulekar, A.H.

    Fecundity in the horse-shoe crab Carcinoscorpius rotundicauda ranges from 4217 to 10,982 with an average of 7438. The ova diameter varies between 1.5-2.3 mm with a model value of 1.7 mm. Number of ova per mm carapace length, per g body weight...

  15. The Oblique Art of Shoes: Popular Culture, Aesthetic Pleasure, and the Humanities

    NARCIS (Netherlands)

    C. Lindner

    2015-01-01

    This article addresses popular culture and the humanities. It uses shoes as an object of analysis to interrogate the place and function of aesthetic pleasure in critical thinking and cultural practice in the age of globalization and the neoliberal university. Tracking contemporary articulations of t

  16. Rocker shoes reduce Achilles tendon load in running and walking in patients with chronic Achilles tendinopathy

    NARCIS (Netherlands)

    Sobhani, Sobhan; Zwerver, Johannes; van den Heuvel, Edwin; Postema, Klaas; Dekker, Rienk; Hijmans, Juha M.

    2015-01-01

    OBJECTIVES: Relative rest and pain relief play an important role in the management of Achilles tendinopathy, and might be achieved by reducing the load on the Achilles tendon. Previous studies have provided evidence that rocker shoes are able to decrease the ankle internal plantar flexion moment in

  17. The knee adduction moment measured with an instrumented force shoe in patients with knee osteoarthritis

    NARCIS (Netherlands)

    Noort, van den Josien C.; Esch, van der Martin; Steultjens, Martijn P.M.; Dekker, Joost; Schepers, H. Martin; Veltink, Peter H.; Harlaar, Jaap

    2012-01-01

    The external knee adduction moment (KAdM) during gait is an important parameter in patients with knee osteoarthritis (OA). KAdM measurement is currently restricted to instruments only available in gait laboratories. However, ambulatory movement analysis technology, including instrumented force shoes

  18. Association Between Causal Beliefs and Shoe Wearing to Prevent Podoconiosis: A Baseline Study.

    Science.gov (United States)

    Ayode, Desta; Tora, Abebayehu; Farrell, David; Tadele, Getnet; Davey, Gail; McBride, Colleen M

    2016-05-01

    Podoconiosis is a neglected tropical disease caused by long-term barefoot exposure to volcanic clay soil. Our previous qualitative research identified various domains of beliefs about the causes of podoconiosis held by members of the community. This cross-sectional survey, conducted in southern Ethiopia, aimed to quantitatively evaluate the prevalence of these beliefs and to assess their association with observed shoe-wearing behavior. A total of 1,800 adult respondents (600 from affected families and 1,200 from unaffected families of an index child aged between 3 and 6 years) took part in the survey. Two standardized versions of an enumerator-administered survey were created, with "all day, everyday" shoe-wearing status of the index child assessed in parallel for the affected and unaffected household respondents. Associations between measures were assessed using logistic regression. Accuracy of understanding about podoconiosis was significantly lower among respondents from unaffected than affected households (P child (odds ratio = 0.67, 95% confidence interval = 0.55-0.83). In both groups, associations of causal beliefs with shoe wearing were moderated by risk perceptions. Interventions aimed at preventing podoconiosis and improving shoe wearing should consider family-oriented education on hereditary susceptibility that targets affected and unaffected families in resource-limited settings. PMID:26928843

  19. Identification of virtual grounds using virtual reality haptic shoes and sound synthesis

    DEFF Research Database (Denmark)

    Serafin, Stefania; Turchet, Luca; Nordahl, Rolf;

    2010-01-01

    We describe a system which simulates in real-time the auditory and haptic sensation of walking on different surfaces. The system is based on physical models, that drive both the haptic and audio synthesizers, and a pair of shoes enhanced with sensors and actuators. In a discrimination experiment,...

  20. Regenerative Braking Algorithm for an ISG HEV Based on Regenerative Torque Optimization

    Institute of Scientific and Technical Information of China (English)

    XIAO Wen-yong; WANG Feng; ZHUO Bin

    2008-01-01

    A novel regenerative braking algorithm based on regenerative torque optimization with emulate engine compression braking (EECB) was proposed to make effective and maximum use of brake energy in order to improve fuel economy. The actual brake oil pressure of driving wheel which is reduced by the amount of the regenerative braking force is supplied from the electronic hydraulic brake system. Regenerative torque optimization maximizes the actual regenerative power recuperation by energy storage component, and EECB is a useful extended type of regenerative braking. The simulation results show that actual regenerative power recuperation for the novel regenerative braking algorithm is more than using conventional one, and life-span of brake disks is prolonged for the novel algorithm.

  1. Sistem Pendingin Paksa Anti Panas Lebih (Over Heating pada Rem Cakram (Disk Brake Kendaraan

    Directory of Open Access Journals (Sweden)

    Joni Dewanto

    2010-01-01

    Full Text Available Until now, the vehicle brakes are not usually equipped with a special cooling system, so that the release of heat into the air occurs naturally. When used continuously, the brakes can suffer damage as a result of the occurrence of over-heating. This condition is potentially causing a fatal accident. Physically, the over-heating often occurs in type disc brake, because the heat transfer surface is less proportionately, especially for high braking loads. This research aims to develop a brake disc with an active cooling system to prevent overheating. The system is applied to a simulated model of disc brakes empirically. The test was conducted at several levels of constant disc speed and breaking force. The results of this research indicate that at various braking load, the development of disc brakes with an active cooling system in the form of water vapor that is sprayed, can control the brake temperature rise and prevent over-heating.

  2. 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.

  3. 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.

  4. Multivariate Multiscale Entropy Applied to Center of Pressure Signals Analysis: An Effect of Vibration Stimulation of Shoes

    OpenAIRE

    Jiann-Shing Shieh; Chuan Wu; Jiang, Bernard C.; Ku-Ping Chen; Maysam F. Abbod; Quan Liu; Qin Wei; Kai-Hong Wang; Dong-Hai Liu

    2012-01-01

    Falls are unpredictable accidents and resulting injuries can be serious to the elderly. A preventative solution can be the use of vibration stimulus of white noise to improve the sense of balance. In this work, a pair of vibration shoes were developed and controlled by a touch-type switch which can generate mechanical vibration noise to stimulate the patient’s feet while wearing the shoes. In order to evaluate the balance stability and treatment effect of vibrating insoles in these shoes, mul...

  5. Electro-mechanical Braking Method in Hybrid Electric Vehicles Based on Feedback Control Theory

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; YU Jun-quan; LIU Zheng-yu; CHANG Cheng

    2014-01-01

    In this paper, the hybrid electric vehicle braking process is researched, by using variables consists of HEV speed, motor speed, and state of charge established, functions of mechanical braking force, regenerative braking force and efficiency of energy recovery are constructed, and the control goal is to maximization the energy recovery efficiency. Under the feedback control strategy, with the constrain condition of braking strength and braking stability, combining experiments in ADVISOR, in different experiments of different working conditions, we can see that in UDDS Cycle, the regenerative braking efficiency is the best. What’s more, compared with strategies in ADVISOR, strategy proposed in this paper is obviously better.

  6. An integrated control strategy for the composite braking system of an electric vehicle with independently driven axles

    Science.gov (United States)

    Sun, Fengchun; Liu, Wei; He, Hongwen; Guo, Hongqiang

    2016-08-01

    For an electric vehicle with independently driven axles, an integrated braking control strategy was proposed to coordinate the regenerative braking and the hydraulic braking. The integrated strategy includes three modes, namely the hybrid composite mode, the parallel composite mode and the pure hydraulic mode. For the hybrid composite mode and the parallel composite mode, the coefficients of distributing the braking force between the hydraulic braking and the two motors' regenerative braking were optimised offline, and the response surfaces related to the driving state parameters were established. Meanwhile, the six-sigma method was applied to deal with the uncertainty problems for reliability. Additionally, the pure hydraulic mode is activated to ensure the braking safety and stability when the predictive failure of the response surfaces occurs. Experimental results under given braking conditions showed that the braking requirements could be well met with high braking stability and energy regeneration rate, and the reliability of the braking strategy was guaranteed on general braking conditions.

  7. 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.

  8. 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.

  9. 大客车制动蹄片使用寿命的试验研究%Test Research on the Brake Shoes Wearing Life for Large Coaches

    Institute of Scientific and Technical Information of China (English)

    魏昌宏

    2008-01-01

    根据多年的道路试验经验,结合某12 m客车9万多km可靠性试验记录,引出"当量制动率"的概念,并对几种路况下的当量制动率进行研究,探索制动蹄片可靠性试验数据与实际寿命之间的关系.

  10. Piecewise polynomial chaos expansion with an application to brake squeal of a linear brake system

    Science.gov (United States)

    Sarrouy, E.; Dessombz, O.; Sinou, J.-J.

    2013-02-01

    This paper proposes numerical developments based on polynomial chaos (PC) expansions to process stochastic eigenvalue problems efficiently. These developments are applied to the problem of linear stability calculations for a simplified brake system: the stability of a finite element model of a brake is investigated when its friction coefficient or the contact stiffness are modeled as random parameters. Getting rid of the statistical point of view of the PC method but keeping the principle of a polynomial decomposition of eigenvalues and eigenvectors, the stochastic space is decomposed into several elements to realize a low degree piecewise polynomial approximation of these quantities. An approach relying on continuation principles is compared to the classical dichotomy method to build the partition. Moreover, a criterion for testing accuracy of the decomposition over each cell of the partition without requiring evaluation of exact eigenmodes is proposed and implemented. Several random distributions are tested, including a uniform-like law for description of friction coefficient variation. Results are compared to Monte Carlo simulations so as to determine the method accuracy and efficiency. Some general rules relative to the influence of the friction coefficient or the contact stiffness are also inferred from these calculations.

  11. 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.

  12. Charging valve of the full hydraulic braking system

    Directory of Open Access Journals (Sweden)

    Jinshi Chen

    2016-03-01

    Full Text Available It is known that the full hydraulic braking system has excellent braking performance. As the key component of the full hydraulic braking system, the parameters of the accumulator charging valve have a significant effect on the braking performance. In this article, the key parameters of the charging valve are analyzed through the static theoretical and an Advanced Modeling Environment for performing Simulation of engineering systems (AMESim simulation model of the dual-circuit accumulator charging valve is established based on the real structure parameters first. Second, according to the results of the dynamic simulation, the dynamic characteristics of the charging pressure, the flow rate, and the frequency of the charging valve are studied. The key parameters affecting the serial production are proposed and some technical advices for improving the performance of the full hydraulic system are provided. Finally, the theoretical analysis is validated by the simulation results. The comparison between the simulation results and the experimental results indicates that the simulated AMESim model of the charging valve is accurate and credible with the error rate inside 0.5% compared with the experimental result. Hence, the performance of the charging valve meets the request of the full hydraulic braking system exactly.

  13. Hall drift and the braking indices of young pulsars

    CERN Document Server

    Gourgouliatos, K N

    2014-01-01

    Braking index measurements of young radio pulsars are all smaller than the value expected for spin down by magnetic dipole braking. We investigate magnetic field evolution in the neutron star crust due to Hall drift as an explanation for observed braking indices. Using numerical simulations and a semi-analytic model, we show that a $\\approx 10^{14}\\ {\\rm G}$ quadrupolar toroidal field in the neutron star crust at birth leads to growth of the dipole moment at a rate large enough to agree with measured braking indices. A key factor is the density at which the crust yields to magnetic stresses that build up during the evolution, which sets a characteristic minimum Hall timescale. The observed braking indices of pulsars with inferred dipole fields of $\\lesssim 10^{13}\\ {\\rm G}$ can be explained in this picture, although with a significant octupole component needed in some cases. For the stronger field pulsars, those with $B_d\\gtrsim 10^{13}\\ {\\rm G}$, we find that the magnetic stresses in the crust exceed the max...

  14. Unusual Braking Indices in Young X-ray Pulsars

    Science.gov (United States)

    Frederic Archibald, Robert; Kaspi, Victoria M.; Beardmore, Andrew P.; Gehrels, Neil; Kennea, Jamie; Gotthelf, Eric V.; Ferdman, Robert; Guillot, Sebastien; Harrison, Fiona; Keane, Evan; Pivovaroff, Michael; Stern, Daniel; Tendulkar, Shriharsh P.; Tomsick, John

    2016-04-01

    Pulsars spin down over time. By measuring braking indices of pulsars, effectively the change in the spin-down rate over time, we can probe the underlying driving engine of the spin-down. For a magnetic dipole in a vacuum, n is predicted to be 3. To date, all measured braking indices are less than 3, which can be explained, e.g. by particle winds, changes in the magnetic field. In all models of braking indices, n should be nearly constant on year time-scales. Here, I will discuss two recent observation results that challenge this model, interestingly both coming from young X-ray pulsars with no detected radio emission. The first, a long-lived decrease in the braking index of PSR J1846-0258 following a burst of magnetar-like activity, and secondly, the first stationary braking index greater than three. Understanding neutron-star spin evolution is key to constraining these objects' long-term energy output and has relevance to topics ranging from pulsar wind nebulae and supernova remnants to core-collapse supernova rates, physics, and expected outcomes.

  15. Evaluation and Optimization of Therapeutic Footwear for Neuropathic Diabetic Foot Patients Using In-Shoe Plantar Pressure Analysis

    OpenAIRE

    Bus, Sicco A.; Haspels, Rob; Busch-Westbroek, Tessa E.

    2011-01-01

    OBJECTIVE Therapeutic footwear for diabetic foot patients aims to reduce the risk of ulceration by relieving mechanical pressure on the foot. However, footwear efficacy is generally not assessed in clinical practice. The purpose of this study was to assess the value of in-shoe plantar pressure analysis to evaluate and optimize the pressure-reducing effects of diabetic therapeutic footwear. RESEARCH DESIGN AND METHODS Dynamic in-shoe plantar pressure distribution was measured in 23 neuropathic...

  16. 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.

  17. Maslov-type index and brake orbits in nonlinear Hamiltonian systems

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, we study the Maslov-type index theory for linear Hamiltonian systems with brake orbits boundary value conditions and its applications to the existence of multiple brake orbits of nonlinear Hamiltonian systems.

  18. Product and process innovation of grey cast iron brake discs

    Energy Technology Data Exchange (ETDEWEB)

    Schorn, M. [Brembo S.P.A. (Italy)

    2006-07-01

    The brake disc out of grey cast iron often seems to be playing the role of the ''underdog'' in the technical examinations of the entire brake system. This is also reflected by the 25 year history of the {mu}-club. In a total of 93 presentations in those 25 years, only 3 were related to the topic of grey cast iron discs. This is not a correct relation to the importance of this component within the brake system. The disc, although per definition with a lower specific load than the pad, has the major task to store and dissipate the heat in which the kinetic energy of the vehicle is transformed. The disc also has a significant effect on NVH behaviour, particularly in the low frequency range. It also has a permanent fight with its weight as an unsprung mass. (orig.)

  19. 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.

  20. 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.

  1. Braking the Gas in the beta Pictoris Disk

    CERN Document Server

    Fern'andez, R; Wu, Y; Brandeker, Alexis; Fern\\'andez, Rodrigo

    2006-01-01

    (Abridged) The main sequence star beta Pictoris hosts the best studied circumstellar disk to date. Nonetheless, a long-standing puzzle has been around since the detection of metallic gas in the disk: radiation pressure from the star should blow the gas away, yet the observed motion is consistent with Keplerian rotation. In this work we search for braking mechanisms that can resolve this discrepancy. We find that all species affected by radiation force are heavily ionized and dynamically coupled into a single fluid by Coulomb collisions, reducing the radiation force on species feeling the strongest acceleration. For a gas of solar composition, the resulting total radiation force still exceeds gravity, while a gas of enhanced carbon abundance could be self-braking. We also explore two other braking agents: collisions with dust grains and neutral gas. Grains surrounding beta Pic are photoelectrically charged to a positive electrostatic potential. If a significant fraction of the grains are carbonaceous (10% in t...

  2. 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.

  3. 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.

  4. Thermal Modeling of Disc Brake Rotor in Frictional Contact

    Science.gov (United States)

    Ali, Belhocine; Ghazaly, Nouby Mahdi

    2013-01-01

    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 analyze 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. The analysis also gives us, the heat flux distribution for the two discs.

  5. Engineering specification and system design for CAD/CAM of custom shoes: UMC project effort

    Science.gov (United States)

    Bao, Han P.

    1991-01-01

    The goal of this project is to supplement the footwear design system of North Carolina State University (NCSU) with a software module to design and manufacture a combination sole. The four areas of concentration were: customization of NASCAD (NASA Computer Aided Design) to the footwear project; use of CENCIT data; computer aided manufacturing activities; and beginning work for the bottom elements of shoes. The task of generating a software module for producing a sole was completed with a demonstrated product realization. The software written in C was delivered to NCSU for inclusion in their design system for custom footwear known as LASTMOD. The machining process of the shoe last was improved using a spiral tool path approach.

  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. Shoe Shine Entrepreneurs Social Responsibility Practices on Loyalty in Eldoret Town, Kenya

    OpenAIRE

    Matelong K. Nebert; Sergon C. David; Tuwei J. Gloria; Cheptumo J. Irene

    2013-01-01

    Micro Enterprises providing services for example haircutting, key making, M-pesa, hair dressing, child care,cleaning, video selling, hawkers and shoe shining to mention but a few find it difficult to envision and understandwhat aspect connote high quality to consumers, and the levels of the aspects that are required to deliver highquality service. Only when these enterprises have a fairly definite knowledge on how the service they offer wouldbe perceived by customers, then they will be able t...

  8. Kinematic adaptations to a variable stiffness shoe: mechanisms for reducing joint loading

    OpenAIRE

    Boyer, K.; Federolf, Peter; Lin, C.; Nigg, Benno; Andriacchi, T. P.

    2012-01-01

    A recently described variable-stiffness shoe has been shown to reduce the adduction moment and pain in patients with medial-compartment knee osteoarthritis. The mechanism associated with how this device modifies overall gait patterns to reduce the adduction moment is not well understood. Yet this information is important for applying load modifying intervention for the treatment of knee osteoarthritis. A principal component analysis (PCA) was used to test the hypothesis that there are dif...

  9. Effect of grouser height on tractive performance of single grouser shoe under different moisture contents soil

    OpenAIRE

    Jun Ge; Xiulun Wang; Koji Kito; Hiroshi Nakashima

    2015-01-01

    The soil condition and grouser height of the track equipped on the crawler vehicle have a significant influence on tractive performance. The purpose of this study is to investigate the grouser height affect on tractive performance of a single grouser shoe under different soil moisture contents. Ten different moisture contents of clay soil were provided in this study. For each moisture contents, a penetration test, a direct shearing test, as well as density and moisture content measurements we...

  10. 'It's gotta be da shoes': domestic manufacturing, international subcontracting, and the production of athletic footwear

    OpenAIRE

    R Barff; Austen, J.

    1993-01-01

    An apparent paradox exists in the geography of athletic footwear production. The industry is highly labor intensive; it is also locationally volatile. Although most production now takes place in Southeast Asia, the United States nevertheless still contains significant enclaves of athletic footwear production. Moreover, the cheapest shoes continue to be produced in the United States whereas more complex, expensive models tend to be manufactured in Asia. To understand this geography, we must mo...

  11. SPORTS SHOES PURCHASE INTENTION AMONG MALAYSIAN VOLLEYBALL PLAYERS VS. NON-VOLLEYBALL PLAYERS: A CONCEPTUAL PAPER

    OpenAIRE

    GOH PIN SIANG; ZURAIDAH SULAIMAN

    2013-01-01

    The purpose of this study is to advance the understanding of volleyball players’ purchase intention toward sport shoes by investigating the relationship between the independent variables (endorsement, advertising, pricing and electronic word-of-mouth) and purchase intention. Descriptive research and causal research will be used as the research design, thus questionnaire and experimentation will be used to obtain data. Primary data in this study is attained by distributing the questionnaire to...

  12. CONTRIBUTIONS TO THE DETERMINATION OF A MOULDING MATERIALS OTHER THAN STIFFENERS AND SHOES INSOLES

    OpenAIRE

    Cornelia LUCA; IONESCU Cozmin

    2015-01-01

    The footwear insoles and heel counter stiffeners are made using fibrous structure materials. The spatial forming of these parts is made in moulds. After forming, the parts must have the same spatial dimensions with those of the shoe lasts used in the footwear manufacturing. During the forming process, the fibrous structure materials have an elastic-plastic behavior. So, for the moulds dimensioning, it is important to know the percentage of plastic deformation from the total deformation of the...

  13. The influence of shoe drop on the kinematics and kinetics of children tennis players.

    Science.gov (United States)

    Herbaut, Alexis; Chavet, Pascale; Roux, Maxime; Guéguen, Nils; Gillet, Christophe; Barbier, Franck; Simoneau-Buessinger, Emilie

    2016-11-01

    This study investigated the immediate effects of reducing the shoe drop (i.e. the difference between the heel and the forefoot height) on the kinematics and kinetics of the lower extremities of children tennis players performing a tennis-specific movement. Thirteen children tennis players performed a series of simulated open stance forehands wearing 3 pairs of shoes differing only in the drop: 0 (D0), 6 (D6) and the control condition of 12 mm (D12). Two embedded forceplates and a motion capture system were used to analyse the ground reaction forces and ankle and knee joint angles and moments of the leading lower limb. In D6 compared with D12, the peak impact force was reduced by 24% (p = .004) and the ankle was less dorsiflexed at foot strike (p = .037). In D0 compared with D12, the peak impact force was reduced by 17% (p = .049), the ankle was less dorsiflexed at foot strike (p = .045) and the knee was more flexed at foot strike (p = .007). In addition, 4 out of 13 participants (31%) presented a forefoot strike pattern for some of the trials in D0. No difference was observed across shoe conditions for the peak knee extensor moment (p = .658) or the peak ankle plantarflexor moment (p = .071). The results provide preliminary data supporting the hypothesis that for children tennis players, using a 6-mm lower shoe drop might reduce heel impact forces and thus limit potentially impact-related injuries.

  14. Nasal cancer in the Northamptonshire boot and shoe industry: is it declining?

    OpenAIRE

    Acheson, E D; Pippard, E C; Winter, P D

    1982-01-01

    This paper reports a survey of nasal cancer in Northamptonshire during the period 1950-79. An increased risk of various histological types of nasal tumour has been observed within the footwear manufacturing industry, which seems to be limited to the minority of men and women exposed to the dust of leather soles and heels. In Northamptonshire this exposure has usually occurred in the preparation, press and finishing rooms of factories making boots and shoes by the welted process. This type of ...

  15. ASPECTS OF THE TECHNOLOGICAL PROCESS OF MANUFACTURING – SEWING A FOOTWEAR PRODUCT FOR WOMEN, TYPE SHOE

    OpenAIRE

    Cristina Secan; Florentina Harnagea

    2013-01-01

    This paper presents the technological process for manufacturing a low-cut footwear product (type shoe) for women, for casual use, in an IL system.The paper begins with a general presentation of the technological process of manufacturing the product, and follows with a case study which details the characteristic operations, as well as the common ones, which take place during the process.Depending on the structure of the model and the characteristics of the raw and auxiliary materials, the tech...

  16. 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...

  17. 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…

  18. 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.

  19. 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.

  20. 49 CFR 214.529 - In-service failure of primary braking system.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false In-service failure of primary braking system. 214... Maintenance Machines and Hi-Rail Vehicles § 214.529 In-service failure of primary braking system. (a) In the event of a total in-service failure of its primary braking system, an on-track roadway...

  1. 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.

  2. An optimized design of in-shoe heel lifts reduces plantar pressure of healthy males.

    Science.gov (United States)

    Zhang, Xianyi; Li, Bo; Liang, Kaiyun; Wan, Qiufeng; Vanwanseele, Benedicte

    2016-06-01

    Conventional heel lift with a flat surface increases the risk of foot problems related to higher plantar pressure and decreased stability. In this study, an optimized design of in-shoe heel lifts developed to maintain the midfoot function was tested to investigate if the plantar pressure distribution was improved. The design was based on three dimensional foot plantar contour which was captured by an Infoot 3D scanning system while the heel was elevated by a heel wedge. To facilitate midfoot function, an arch support was designed to support the lateral longitudinal arch, while allowing functional movement of the medial longitudinal arch. Twenty healthy male subjects were asked to walk along an 8m walkway while wearing high-cut footwear with and without the optimized heel lift. Peak pressure, contact area and force-time integral were measured using the Pedar insole system. Range and velocity of medial-lateral center of pressure during forefoot contact phase and foot flat phase were collected using a Footscan pressure plate. Compared to the shoe only condition, peak pressure under the rearfoot decreased with the optimized heel lift, while no increase of peak pressure was observed under the forefoot and midfoot regions, indicating improved plantar pressure distribution. The findings of this study suggest that this optimized heel lift has better biomechanical performance than a conventional flat heel lift. Results from this study may have implications for insole and shoe last design, especially for people who need additional heel height without sacrificing midfoot function.

  3. Measurement of Lubricating Condition between Swashplate and Shoe in Swashplate Compressors under Practical Operating Conditions

    Science.gov (United States)

    Suzuki, Hisashi; Fukuta, Mitsuhiro; Yanagisawa, Tadashi

    In this paper, lubricating conditions between a swashplate and a shoe in a swashplate compressor for automotive air conditioners is investigated experimentally. The conditions are measured with an electric resistance method that utilizes the swash plate and the shoe as electrodes respectively. The instrumented compressor is connected to an experimental cycle with R134a and operated under various operating conditions of pressure and rotational speed. An improved measurement technique and applying a solid contact ratio to the measurement results permit to measure the lubricating condition at high rotational speed (more than 8000 rpm) and to predic an occurrence of scuffing between the swashplate and the shoe, and therefore enables a detailed study of lubricating characteristics. It is shown by the measurement that the voltage of the contact signal decreases, which means better lubricating condition, with the decrease of the compression pressure and with the increase of the rotational speed from 1000 rpm through 5000 rpm. The lubricating condition tends to worsen at more than 5000 rpm. Furthermore, it is confirmed that the lubricating condition under transient operation is worse obviously as compared with that under steady-state operation.

  4. Wireless patient monitoring on shoe for the assessment of foot dysfunction: an overview

    Science.gov (United States)

    Abraham, Jose K.; Whitchurch, Ashwin K.; Varadan, Vijay K.; Sarukesi, Karunakaran

    2003-04-01

    This paper presents an overview of the wireless monitoring and quantitative assessment of joint dynamics of ankle which has suffered from soft tissue injury, immobilization or any dysfunction with special focus on the treatment and rehabilitation applications. The inadequacy of a reliable and easy method for continuous measurement and recording of ankle movement while doing physical therapy makes the monitoring of its progress difficult. Development of a wireless ankle motion monitoring system inside the shoe provides information on several aspects of activities associated with a dysfunctional foot. The system is based on continuous wireless monitoring of signals from accelerometers and gyroscopes fixed inside the shoe. From these signals, the duration, rate, and moment of occurrence of activities associated with mobility (e.g., lying, sitting, standing, walking up and down, running, cycling, wheelchair use and general movement) and transitions (changes in angle) can be detected. Information about the movement can be obtained by the acceleration sensors, which is related to the intensity of body-segment movement. Apart from monitoring accelerations, other signals due to turning and angular movements can be obtained using the miniature gyroscope attached to the shoe.

  5. EFFECTS OF UNSTABLE SHOES ON ENERGY COST DURING TREADMILL WALKING AT VARIOUS SPEEDS

    Directory of Open Access Journals (Sweden)

    Keiji Koyama

    2012-12-01

    Full Text Available In recent years, shoes having rounded soles in the anterior- posterior direction have been commercially introduced, which are commonly known as unstable shoes (US. However, physiological responses during walking in US, particularly at various speeds, have not been extensively studied to date. The purpose of this study was to investigate the effect of wearing unstable shoes while walking at low to high speeds on the rate of perceived exertion (RPE, muscle activation, oxygen consumption (VO2, and optimum speed. Healthy male adults wore US or normal walking shoes (WS, and walked at various speeds on a treadmill with no inclination. In experiment 1, subjects walked at 3, 4, 5, 6, and 7 km·h-1 (duration, 3 min for all speeds and were recorded on video from the right sagittal plane to calculate the step length and cadence. Simultaneously, electromyogram (EMG was recorded from six different thigh and calf muscles, and the integrated EMG (iEMG was calculated. In experiment 2, RPE, heart rate and VO2 were measured with the walking speed being increased from 3.6 to 7.2 km·h-1 incrementally by 0.9 km·h-1 every 6 min. The optimum speed, defined by the least oxygen cost, was calculated from the fitted quadratic relationship between walking speed and oxygen cost. Wearing US resulted in significantly longer step length and lower cadence compared with WS condition at any given speed. For all speeds, iEMG in the medial gastrocnemius and soleus muscles, heart rate, and VO2 were significantly higher in US than WS. However, RPE and optimum speed (US, 4.75 ± 0.32 km·h-1; WS, 4. 79 ± 0.18 km·h-1 did not differ significantly between the two conditions. These results suggest that unstable shoes can increase muscle activity of lower legs and energy cost without influencing RPE and optimum speed during walking at various speeds

  6. Post-marathon wearing of Masai Barefoot Technology shoes facilitates recovery from race-induced fatigue: an evaluation utilizing a visual analog scale

    Directory of Open Access Journals (Sweden)

    Nakagawa K

    2014-12-01

    Full Text Available Kento Nakagawa, Takashi Obu, Kazuyuki KanosueFaculty of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan Purpose: To investigate the potential benefit of post-race wearing of unstable shoes (Masai Barefoot Technology [MBT] on recovery from marathon race–induced fatigue.Patients and methods: Forty-five runners who participated in a full marathon race were divided into three groups: 1 MBT shoes, 2 trail running shoes, and 3 control (CON. Participants ran a full marathon with their own running shoes, and then put on the assigned shoes immediately after the race. They continued to wear the assigned shoes for the ensuing 3 days. The CON group wore their usual shoes. Estimates of post-race fatigue were made by the participants on questionnaires that utilized a visual analog scale. Estimates were made just after the race, as well as for the next 3 days.Results: The subjective fatigue of the MBT group was lower than that of the CON (P<0.05 or trail running shoe groups (P<0.05 on day 3.Conclusion: MBT shoe intervention can promote recovery from the fatigue induced by running a full marathon.Keywords: footwear, VAS, full marathon

  7. Design of Braking Caliper's Braking Torque in Hydraulic Disc Braking System%液压盘式刹车系统制动钳制动力矩的设计

    Institute of Scientific and Technical Information of China (English)

    高燕; 宋胜涛; 王跃军; 韩美香; 郭太清

    2012-01-01

    针对目前液压盘式刹车系统刹车力矩小,刹车性能不稳定等现状,基于老算法对制动转矩的计算原理设计了一种新算法,对制动钳的工作制动转矩,紧急制动转矩及驻车制动转矩,冗余安全设计等进行了计算.为提高液压盘式刹车系统的设计效率和安全系数,该算法从制动钳的工作原理出发,通过对制动钳的制动结构进行分析,以下放到井中的最重套管柱所形成的静制动转矩作为盘刹系统能满足的最小工作制动转矩为依据,通过验证计算结果,保障了液压盘式刹车系统的安全性和有效性.%The current braking torque of the hydraulic disc braking system is small and braking performance is instable.A new algorithm was designed based on the braking torque's calculation of the old algorithm.The work braking torque, emergency braking torque, park braking torque and the redundant safety design were calculated in this new algorithm.To improve the design efficiency and safety coefficient of the hydraulic disc braking system, the algorithm based on the working principle of the braking caliper, through the braking structure analysis of the braking caliper, according to the static braking torque formed by the heaviest casing string that put into the well could be taken as the minimum working braking torque which the disc braking system could meet.The safety and effectiveness of the hydraulic disc braking system are safeguarded through the authentication and calculation of the result.

  8. Smart brake light system would provide more information to drivers

    OpenAIRE

    Trulove, Susan

    2008-01-01

    You are driving in heavy traffic. The brake lights on the car in front of you come on. Is the car slowing or is it going to stop? It slows to 25 mph and the lights go off. You drop back. The car in front of you stops suddenly! You stop just in time. The car behind you collects your rear bumper.

  9. 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.

  10. 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.

  11. 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....

  12. 49 CFR 571.106 - Standard No. 106; Brake hoses.

    Science.gov (United States)

    2010-10-01

    ... Vehicle Safety Standards § 571.106 Standard No. 106; Brake hoses. S1. Scope. This standard specifies... end fittings. S2. Purpose. The purpose of this standard is to reduce deaths and injuries occurring as.... S3. Application. This standard applies to passenger cars, multipurpose passenger vehicles,...

  13. 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,

  14. 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...

  15. 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.

  16. Coaxial magnetic brakes using single-domain YBCO

    Energy Technology Data Exchange (ETDEWEB)

    Putman, P.T. [Texas Center for Superconductivity and Department of Mechanical Engineering, University of Houston, Houston, TX 77204 (United States)], E-mail: pputman@uh.edu; Salama, K. [Texas Center for Superconductivity and Department of Mechanical Engineering, University of Houston, Houston, TX 77204 (United States)

    2008-06-15

    In coaxial magnetic brakes, the changing field produced by movement of a solenoidal magnet induces a current in the wall of a conductive tube. The interaction of the field and current leads to a repulsive force that slows the motion of the magnet. For brake applications that require high force density, melt-textured YBCO is a clear choice of material for the magnet because it can carry high currents at a given field and temperature, and is inherently capable of operating in persistent current mode. We present calculations of the performance of this type of brake as a function of magnet current density for catch tubes composed of aluminum and titanium. These results are validated with low speed (20 m/s) tests. Calculations indicate that melt-textured magnets can decelerate projectiles with a mass of 1 kg from 2000 m/s to rest in distances on the order of 10 m. This suggests that this type of brake is suitable for use in hypervelocity experiments, which sometimes requires nondestructive deceleration of projectiles for diagnostic purposes.

  17. CFD Analysis of Automotive Ventilated Disc Brake Rotor

    Directory of Open Access Journals (Sweden)

    Amol V. More

    2014-04-01

    Full Text Available Disc brakes work on the principle of friction by converting kinetic energy into heat energy. The key objective of a disc brake rotor is to accumulate this heat energy and dissipate it immediately. The effect of rotational speed on the aero-thermal performance is assessed. The rotor speed is observed to have substantial effect on the rotor performance. The heat dissipation and thermal performance of ventilated brake discs intensely be influenced by the aerodynamic characteristics of the air flow through the rotor passages. In order to investigate the aero-thermal performance of the ventilated disc brake at several altered driving speeds of the vehicle, the simulations were carried out at 3 different rotational speeds of 44rad/s 88 rad/s and 120 rad/s. The semi-automatic geometric model is created using the package Solid Works and the mesh for the model is done using ICEM CFD and the Post processing of the results is done using FLUENT-14.5.The results are discussed and presented in detail.

  18. ANALYSIS OF FAILURE MECHANISM IN MULTIPLE DISC WET BRAKES

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    By the numberical calculation of dynamic lining pressure distributions,temperature fields and thermal stress fields of steel plates,a method using nonlinear finite element techniques to analyze failure mechanism of a multiple disc wet brake is detailed ,and some measures for combatting these failures are provided.

  19. 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...

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

    Science.gov (United States)

    Hockicko, Peter; Trpišová, Beáta; Ondruš, Ján

    2014-12-01

    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 obtaining their estimates of these quantities before and after watching a video recording of a car braking from various initial speeds to a complete stop and subsequent application of mathematical statistics to the obtained sets of students' answers. The results revealed that the difference between the value of the car braking distance estimated before watching the video and the real value of this distance was not caused by a random error but by a systematic error which was due to the incorrect students' conceptions about the car braking process. Watching the video significantly improved the students' estimates of the car braking distance, and we show that in this case, the difference between the estimated value and the real value of the car braking distance was due only to a random error, i.e. the students' conceptions about the car braking process were corrected. Some of the students subsequently performed video analysis of the braking processes of cars of various brands and under various conditions by means of Tracker that gave them exact knowledge of the physical quantities, which characterize a motor vehicle braking. Interviewing some of these students brought very positive reactions to this novel method of learning.

  1. SPECIFICITY AND TRENDS IN IMPROVEMENT OF TRACTOR TRAIN BRAKING DYNAMICS

    Directory of Open Access Journals (Sweden)

    G. A. Tayanovsky

    2015-01-01

    Full Text Available The paper considers an important problem in improvement of  braking dynamics potential as part of the overall tractor train dynamics consisting of  an all-wheel drive tractor and heavy-duty trailers which are either locally manufactured or developed with the participation of the paper’s authors. The trailers have a mechanical drive for their wheels from the tractor engine. The trains are intended for transportation peat, organic fertilizers and various loads in  forest exploitation and under other complicated soil and climatic and road conditions where there is justified necessity to activate the trailer wheels.Methodological tools have been developed with the purpose to analyze an influence of the blocked inter-double-reduction axle drive of an active tractor train on distribution of braking forces in double-reduction axles with due account of the heavy-duty peat trailer specificity. Theoretical provisions for wheeled vehicles have been developed with regard to the braking application specificity of active tractor trains with mechanical multi-path drive for wheels of a multi-double-reduction axle propulsion device. The paper presents calculation and theoretical data in order to estimate  distribution of specific braking forces in the double-reduction axle links of the active tractor train when the blocked inter-double-reduction axle drive of the tractor and trailer wheels is switched on and also in the case when the tractor engine is involved in braking process and a clutch coupling is switched-on.Sequence of the calculation formula has been completely carried out in the paper. They represent clear design and operational parameters of the active tractor train. Such approach has made it possible to realize them in the form of a software application which is convenient for analysis of the braking process pertaining to the investigated objects in order to select means for improvement of braking dynamics, rational parameters of multi

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    Fei Gao

    2014-01-01

    Full Text Available 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 radial direction was caused by severe friction in short time and the low heat transfer coefficient of its material. Parametric analysis for disc brakes have been carried out by comparison of grouped brake applications conform to UIC code, the main factor cause the high temperature gradient and thermal stress of brake disc is brake force and its initial speed.

  4. 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.

  5. 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

  6. Multivariate Multiscale Entropy Applied to Center of Pressure Signals Analysis: An Effect of Vibration Stimulation of Shoes

    Directory of Open Access Journals (Sweden)

    Jiann-Shing Shieh

    2012-11-01

    Full Text Available Falls are unpredictable accidents and resulting injuries can be serious to the elderly. A preventative solution can be the use of vibration stimulus of white noise to improve the sense of balance. In this work, a pair of vibration shoes were developed and controlled by a touch-type switch which can generate mechanical vibration noise to stimulate the patient’s feet while wearing the shoes. In order to evaluate the balance stability and treatment effect of vibrating insoles in these shoes, multivariate multiscale entropy (MMSE algorithm is applied to calculate the relative complexity index of reconstructed center of pressure (COP signals in antero-posterior and medio-lateral directions by the multivariate empirical mode decomposition (MEMD. The results show that the balance stability of 61.5% elderly subjects is improved after wearing the developed shoes, which is more than 30.8% using multiscale entropy. In conclusion, MEMD-enhanced MMSE is able to distinguish the smaller differences between before and after the use of vibration shoes in both two directions, which is more powerful than the empirical mode decomposition (EMD-enhanced MSE in each individual direction.

  7. Classification and mass production technique for three-quarter shoe insoles using non-weight-bearing plantar shapes.

    Science.gov (United States)

    Sun, Shuh-Ping; Chou, Yi-Jiun; Sue, Chun-Chia

    2009-07-01

    We have developed a technique for the mass production and classification of three-quarter shoe insoles via a 3D anthropometric measurement of full-size non-weight-bearing plantar shapes. The plantar shapes of fifty 40-60-year-old adults from Taiwan were categorized and, in conjunction with commercially available flat or leisure shoe models, three-quarter shoe-insole models were generated using a CAD system. Applying a rapid prototype system, these models were then used to provide the parameters for manufacturing the shoe insoles. The insoles developed in this study have been classified into S, M and L types that offer user-friendly options for foot-care providers. We concluded that these insoles can mate tightly with the foot arch and disperse the pressure in the heel and forefoot over the foot arch. Thus, practically, the pressure difference over the plantar region can be minimised, and the user can experience comfort when wearing flat or leisure shoes.

  8. In-shoe multi-segment foot kinematics of children during the propulsive phase of walking and running.

    Science.gov (United States)

    Wegener, Caleb; Greene, Andrew; Burns, Joshua; Hunt, Adrienne E; Vanwanseele, Benedicte; Smith, Richard M

    2015-02-01

    Certain styles of children's shoes reduce 1st metatarsophalangeal joint (MTPJ) and midfoot motion during propulsion of walking. However, no studies have investigated if the splinting effect of shoes on children's 1st MTPJ and midfoot motion occurs during running. This study investigated the effect of sports shoes on multi-segment foot kinematics of children during propulsion of walking and running. Twenty children walked and ran at a self-selected velocity while barefoot and shod in a random order. Reflective markers were used to quantify sagittal plane motion of the 1st MTPJ and three-dimensional motion of the midfoot and ankle. Gait velocity increased during shod walking and running and was considered a covariate in the statistical analysis. Shoes reduced 1st MTPJ motion during propulsion of walking from 36.0° to 10.7° and during running from 31.5° to 12.6°. Midfoot sagittal plane motion during propulsion reduced from 22.5° to 6.2° during walking and from 27.4° to 9.6° during running. Sagittal plane ankle motion during propulsion increased during shod running from 26.7° to 34.1°. During propulsion of walking and running, children's sports shoes have a splinting effect on 1st MTPJ and midfoot motion which is partially compensated by an increase in ankle plantarflexion during running.

  9. Climate Based Performance of Carbon-Carbon Disc Brake for High Speed Aircraft Braking System

    Directory of Open Access Journals (Sweden)

    R. M. Mohanty

    2013-09-01

    Full Text Available Carbon composite brake discs are lighter, economical, and have excellent high energy friction characteristics. These have twice thermal capability compared to steel, remain unaffected by thermal shocks and mechanical fatigue. These are highly useful in emergency breaking situations. Prior to this work, two dimensional (2D reinforced carbon composite laminates were prepared through pitch impregnation process. In an effort to protect the exposed non frictional surface from high temperature service degradations, multilayered ceramic coating systems were developed on 2D composite. Oxidation studies have been carried out on these systems viz., C-SiC, C-SiC-MoSi2-Al2O3 and C-SiC-B4C. These were performed both in dynamic and static conditions up to 1200 °C in 60 per cent humid climate. The hardness, surface topography, developed phases and integrity of layers on the samples at various stages of the experiment have been characterized and analyzed. It was observed that C-SiC-B4C system performs well in the oxidizing environment.Defence Science Journal, 2013, 63(5, pp.531-538, DOI:http://dx.doi.org/10.14429/dsj.63.3932

  10. 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

  11. A sample-freezing drive shoe for a wire line piston core sampler

    Science.gov (United States)

    Murphy, F.; Herkelrath, W.N.

    1996-01-01

    Loss of fluids and samples during retrieval of cores of saturated, noncohesive sediments results in incorrect measures of fluid distributions and an inaccurate measure of the stratigraphic position of the sample. To reduce these errors, we developed a hollow drive shoe that freezes in place the lowest 3 inches (75 mm) of a 1.88-inch-diameter (48 mm), 5-foot-long (1.5 m) sediment sample taken using a commercial wire line piston core sampler. The end of the core is frozen by piping liquid carbon dioxide at ambient temperature through a steel tube from a bottle at the land surface to the drive shoe where it evaporates and expands, cooling the interior surface of the shoe to about -109??F (-78??C). Freezing a core end takes about 10 minutes. The device was used to collect samples for a study of oil-water-air distributions, and for studies of water chemistry and microbial activity in unconsolidated sediments at the site of an oil spill near Bemidji, Minnesota. Before freezing was employed, samples of sandy sediments from near the water table sometimes flowed out of the core barrel as the sampler was withdrawn. Freezing the bottom of the core allowed for the retention of all material that entered the core barrel and lessened the redistribution of fluids within the core. The device is useful in the unsaturated and shallow saturated zones, but does not freeze cores well at depths greater than about 20 feet (6 m) below water, possibly because the feed tube plugs with dry ice with increased exhaust back-pressure, or because sediment enters the annulus between the core barrel and the core barrel liner and blocks the exhaust.

  12. Study on the dynamic characteristics of a high frequency brake based on giant magnetostrictive material

    Science.gov (United States)

    Xu, Ai Qun

    2016-06-01

    In order to meet the requirements of rapid and smooth braking, high-frequency braking using a giant magnetostrictive actuator is proposed, which can solve the problems in hydraulic braking, such as, it leaks easily, catches fire easily, is difficult to find failures, high cost on maintenance and repairing, etc. The main factors affecting the force of a high-frequency braking actuator are emphatically analyzed, the brakes dynamic model is established and a performance testing device for high frequency braking is constructed based on LabVIEW. The output force of the actuator increases with the excitation current of the driving coil increasing, and the increased multiple of the output force is greater than that of the excitation current; the range of the actuator force amplitude is 121.63 N ∼ 158.14 N, which changes little, while excitation frequency changes between 200 Hz ∼ 1000 Hz. In a minor range of pre-stress, the output force decreases with an increase in the axial pre-stress of the giant magnetostrictive rod, but is not obvious. It is known by finite element simulation analysis that high-frequency braking shortens the braking displacement and time effectively, which proves the feasibility and effectiveness of high frequency braking. Theoretical analysis and experimental results indicate that the output force of the actuator changes at the same frequency with excitation current; it is controllable and its mechanical properties meet the requirements of high frequency braking.

  13. Diagnostics monitor of the braking efficiency in the on board diagnostics system for the motor vehicles

    Science.gov (United States)

    Gajek, Andrzej

    2016-09-01

    The article presents diagnostics monitor for control of the efficiency of brakes in various road conditions in cars equipped with pressure sensor in brake (ESP) system. Now the brake efficiency of the vehicles is estimated periodically in the stand conditions on the base of brake forces measurement or in the road conditions on the base of the brake deceleration. The presented method allows to complete the stand - periodical tests of the brakes by current on board diagnostics system OBD for brakes. First part of the article presents theoretical dependences between deceleration of the vehicle and brake pressure. The influence of the vehicle mass, initial speed of braking, temperature of brakes, aerodynamic drag, rolling resistance, engine resistance, state of the road surface, angle of the road sloping on the deceleration have been analysed. The manner of the appointed of these parameters has been analysed. The results of the initial investigation have been presented. At the end of the article the strategy of the estimation and signalization of the irregular value of the deceleration are presented.

  14. 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.

  15. Application of ShoeBi CAD Software to Design Footwear%ShoeBi 计算机辅助鞋类设计软件在鞋样设计中的应用

    Institute of Scientific and Technical Information of China (English)

    易蛟巧; 徐波; 黄彬

    2009-01-01

    在我国的制鞋业中产品开发阶段通常运用手绘设计图,ShoeBi软件是一个专业的制鞋软件,其绘图功能集合了通用绘图软件的许多功能以及针对鞋类绘制的专用功能,使得鞋类设计图的绘制更加简单、快速,本文主要针对如何用ShoeBi软件绘制鱼嘴女鞋设计图做详细介绍.

  16. ORTHOPEDIC AND BIOMECHANICAL FEATURES FOR RUNNING SHOES FOR SPRINTS, MEDIUM AND LONG DISTANCES

    OpenAIRE

    Cornelia Ionescu Luca; Cristina Secan

    2013-01-01

    Athletics is the sport discipline that has 3 simple event types and 2 multiple events competitions. The simple events are: running, jumps, and throws and the multiple events competitions are: decathlon and heptathlon. The running events are 100 m, 200 m and 400 m dash and 800 m, 1500 m, 5000 m and 10000 m; 100m, 400 m and 3000 m hurdles; marathon, 20 km and 50 km march and cross-country. Different athletics events will require different types of sport shoes, designed for the specific events....

  17. Complications of surgical extraction of ankylosed primary teeth and distal shoe space maintainers.

    Science.gov (United States)

    Kirshenblatt, S; Kulkarni, G V

    2011-01-01

    The purpose of this report was to present the iatrogenic complications that may result from the management of ankylosed primary teeth as well as describe the case of a patient with an ankylosed primary mandibular left second molar which was surgically extracted and an adjacent primary first molar that was cemented with a distal shoe space maintainer. Aggressive surgical removal of the ankylosed tooth caused damage to the developing crown of the successor. Improper placement of the appliance caused perforation of the developing tooth follicle. Orthodontic therapy and a polycarbonate temporary crown were used to restore occlusion. Nonsurgical extractions and alternative appliances should be considered when treating patients with ankylosed primary second molars.

  18. Shape optimization of pole shoes in harmonic exciting synchronous generators using a stochastic algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Yang Shiyou; Ni Guangzheng [Zhejiang Univ., Hangzhou (China). Dept. of Electrical Engineering; Li Yan; Tang Renyuan [Shenyang Polytechnic Univ. (China)

    1997-03-01

    The optimization of pole shoes in harmonic exciting synchronous generators is effectively performed using the combined strategy of the improved simulated annealing and the genetic algorithm with some new improvements made in this paper. The improvements include the rule for the generation of new states, the adaptive regulation schedule for the length of the interval of the pseudo-random parameter, and the addition of the geometry constraints. Numerical results on different machines reveal that the iterative number used by executing the combined strategy with improvements is only about 50% of that used by executing the original one, while the optimization results obtained using different algorithms are nearly the same.

  19. Internationalization strategy of ABotoa/Skypro shoes to United States of America

    OpenAIRE

    Menezes, Mafalda

    2012-01-01

    A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics In a world where it is even more important to be a global company to remain competitive, it is important that companies act not only regionally but also in foreign markets. In this report, I will develop an internationalization strategy for a small and medium enterprise, Abotoa, in order that one of its brand, SKYRO SHOES enters the USA mark...

  20. Measurement of oil film thickness and friction force on a guide shoe bearing

    DEFF Research Database (Denmark)

    Vølund, Anders

    2002-01-01

    An experimental program was carried out in order to reveal oil film thickness, and friction force of the guide shoe bearing of a large two stroke marine diesel engine. The experiment was conducted on a full size engine located at the research facility at MAN B&W Diesel A/S. The experiment...... was conducted such that the influence from the experiment on the characteristics were as small as possible. The objective of the experiment was to determine the frictional loss of this bearing and to check whether a suggested numerical model was applicable or not. Some future aspects for this bearing...

  1. Audience Intoxicated by Acrobatic Fairy Story——Large Acrobatic Play of Fairy Story Red Dancing Shoes of Chongqing Acrobatic Artistic Troupe

    Institute of Scientific and Technical Information of China (English)

    马洁

    2007-01-01

    In order to celebrate Chongqing as a directly governed city region for ten years and also the First China Chongqing Cultural Artistic Festival, Chongqing Acrobatic Artistic Troupe gave a large acrobatic play of fairy story Red Dancing Shoes. From June 1st to June 3rd, the performance in public of Red Dancing Shoes got a complete success. The media including Chongqing TV Station,

  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. Tearing mode velocity braking due to resonant magnetic perturbations

    Science.gov (United States)

    Frassinetti, L.; Menmuir, S.; Olofsson, K. E. J.; Brunsell, P. R.; Drake, J. R.

    2012-10-01

    The effect of resonant magnetic perturbations (RMPs) on the tearing mode (TM) velocity is studied in EXTRAP T2R. Experimental results show that the RMP produces TM braking until a new steady velocity or wall locking is reached. The braking is initially localized at the TM resonance and then spreads to the other TMs and to the rest of the plasma producing a global velocity reduction via the viscous torque. The process has been used to experimentally estimate the kinematic viscosity profile, in the range 2-40 m2 s-1, and the electromagnetic torque produced by the RMP, which is strongly localized at the TM resonance. Experimental results are then compared with a theoretical model which gives a reasonable qualitative explanation of the entire process.

  4. 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...

  5. 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.

  6. 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.

  7. Analysis of natural frequency variability of a brake component

    Science.gov (United States)

    Gallina, A.; Lisowski, W.; Pichler, L.; Stachowski, A.; Uhl, T.

    2012-10-01

    The manufacture of automotive disc brake calipers is subjected to many inherent variabilities resulting in product variability. In particular, the dispersion of natural frequency values is a primary issue in the context of vehicle comfort. This paper aims to quantify natural frequency variability and search for its causes. Extensive experimental tests and numerical simulations, described in the paper, point out the fundamental role of mold wear and assembling process in this variability.

  8. 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 ...

  9. 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.

  10. The effects of porosity in friction performance of brake pad using waste tire dust

    Directory of Open Access Journals (Sweden)

    İbrahim Mutlu

    2015-10-01

    Full Text Available Abstract This research is focused on the effect of porosity on the friction-wear properties of automotive brake pads. Waste Tire Dust (WTD was used as a new friction material in brake pads. Newly formulated brake pad materials with five different components have been produced by conventional techniques. In the experimental studies, the change of the friction coefficient, the temperature of the friction surface, the specific wear rate, and the hardness, density and porosity were measured. In addition, the micro-structural characterizations of brake pads are determined using Scanning Electron Microscopy (SEM. The mean coefficient of friction, porosity and specific wear are increased due to a WTD rate increases, on the other hand, hardness and density are decreased. As a result, WTD can be considered as an alternative to revalorize this kind of waste products in the brake pads and the amount of porosity of the brake pad affected the friction coefficient and wear behavior of the pad.

  11. A Combined Cooperative Braking Model with a Predictive Control Strategy in an Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Hongqiang Guo

    2013-12-01

    Full Text Available Cooperative braking with regenerative braking and mechanical braking plays an important role in electric vehicles for energy-saving control. Based on the parallel and the series cooperative braking models, a combined model with a predictive control strategy to get a better cooperative braking performance is presented. The balance problem between the maximum regenerative energy recovery efficiency and the optimum braking stability is solved through an off-line process optimization stream with the collaborative optimization algorithm (CO. To carry out the process optimization stream, the optimal Latin hypercube design (Opt LHD is presented to discrete the continuous design space. To solve the poor real-time problem of the optimization, a high-precision predictive model based on the off-line optimization data of the combined model is built, and a predictive control strategy is proposed and verified through simulation. The simulation results demonstrate that the predictive control strategy and the combined model are reasonable and effective.

  12. A simple calibration method for mechanically braked cycle ergometers.

    Science.gov (United States)

    Van Praagh, E; Bedu, M; Roddier, P; Coudert, J

    1992-01-01

    The calibration of cycle ergometers should be checked regularly. Some studies have shown calibration errors of more than 40%. A simple, inexpensive calibrating method for mechanically braked cycle ergometers was developed and tried out on a new type of ergocycle. The cycle ergometer was elevated and the crank replaced by a pulley fitted to the shaft. The crank speed (rpm) increased linearly as a function of time when different masses were applied on the pulley. For a given braking force on the cycle ergometer, different accelerations corresponding to the increased pulley forces could be measured. When extrapolating for zero acceleration, it was possible to determine a "limit-force" which allowed the system to be in equilibrium. Additional force creates motion. The same experiments were repeated with increasing braking forces. Using the differently sized gear sprockets of the transmission system, it was possible to calculate the actual force, including all the resistances. The actual force found by the calibrating method was then compared with the indicated force proposed by the manufacturer. With increasing forces, the relative errors decreased from 9.6 to 2.9%. The cycle ergometer calibrated by this technique meets the standards recommended in exercise physiology. PMID:1544728

  13. Effects of Magnetic Braking and Tidal Friction on Hot Jupiters

    CERN Document Server

    Barker, A J

    2009-01-01

    Tidal friction is thought to be important in determining the long-term spin-orbit evolution of short-period extrasolar planetary systems. Using a simple model of the orbit-averaged effects of tidal friction Eggleton, Kiseleva & Hut (1998), we analyse the effects of the inclusion of stellar magnetic braking on the evolution of such systems. A phase-plane analysis of a simplified system of equations, including only the stellar tide together with a model of the braking torque proposed by Verbunt & Zwaan (1981), is presented. The inclusion of stellar magnetic braking is found to be extremely important in determining the secular evolution of such systems, and its neglect results in a very different orbital history. We then show the results of numerical integrations of the full tidal evolution equations, using the misaligned spin and orbit of the XO-3 system as an example, to study the accuracy of simple timescale estimates of tidal evolution. We find that it is essential to consider coupled evolution of th...

  14. 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.

  15. Physical Behavior in Older Persons during Daily Life: Insights from Instrumented Shoes

    Directory of Open Access Journals (Sweden)

    Christopher Moufawad el Achkar

    2016-08-01

    Full Text Available Activity level and gait parameters during daily life are important indicators for clinicians because they can provide critical insights into modifications of mobility and function over time. Wearable activity monitoring has been gaining momentum in daily life health assessment. Consequently, this study seeks to validate an algorithm for the classification of daily life activities and to provide a detailed gait analysis in older adults. A system consisting of an inertial sensor combined with a pressure sensing insole has been developed. Using an algorithm that we previously validated during a semi structured protocol, activities in 10 healthy elderly participants were recorded and compared to a wearable reference system over a 4 h recording period at home. Detailed gait parameters were calculated from inertial sensors. Dynamics of physical behavior were characterized using barcodes that express the measure of behavioral complexity. Activity classification based on the algorithm led to a 93% accuracy in classifying basic activities of daily life, i.e., sitting, standing, and walking. Gait analysis emphasizes the importance of metrics such as foot clearance in daily life assessment. Results also underline that measures of physical behavior and gait performance are complementary, especially since gait parameters were not correlated to complexity. Participants gave positive feedback regarding the use of the instrumented shoes. These results extend previous observations in showing the concurrent validity of the instrumented shoes compared to a body-worn reference system for daily-life physical behavior monitoring in older adults.

  16. Physical Behavior in Older Persons during Daily Life: Insights from Instrumented Shoes.

    Science.gov (United States)

    Moufawad El Achkar, Christopher; Lenoble-Hoskovec, Constanze; Paraschiv-Ionescu, Anisoara; Major, Kristof; Büla, Christophe; Aminian, Kamiar

    2016-01-01

    Activity level and gait parameters during daily life are important indicators for clinicians because they can provide critical insights into modifications of mobility and function over time. Wearable activity monitoring has been gaining momentum in daily life health assessment. Consequently, this study seeks to validate an algorithm for the classification of daily life activities and to provide a detailed gait analysis in older adults. A system consisting of an inertial sensor combined with a pressure sensing insole has been developed. Using an algorithm that we previously validated during a semi structured protocol, activities in 10 healthy elderly participants were recorded and compared to a wearable reference system over a 4 h recording period at home. Detailed gait parameters were calculated from inertial sensors. Dynamics of physical behavior were characterized using barcodes that express the measure of behavioral complexity. Activity classification based on the algorithm led to a 93% accuracy in classifying basic activities of daily life, i.e., sitting, standing, and walking. Gait analysis emphasizes the importance of metrics such as foot clearance in daily life assessment. Results also underline that measures of physical behavior and gait performance are complementary, especially since gait parameters were not correlated to complexity. Participants gave positive feedback regarding the use of the instrumented shoes. These results extend previous observations in showing the concurrent validity of the instrumented shoes compared to a body-worn reference system for daily-life physical behavior monitoring in older adults. PMID:27527172

  17. Physical Behavior in Older Persons during Daily Life: Insights from Instrumented Shoes

    Science.gov (United States)

    Moufawad el Achkar, Christopher; Lenoble-Hoskovec, Constanze; Paraschiv-Ionescu, Anisoara; Major, Kristof; Büla, Christophe; Aminian, Kamiar

    2016-01-01

    Activity level and gait parameters during daily life are important indicators for clinicians because they can provide critical insights into modifications of mobility and function over time. Wearable activity monitoring has been gaining momentum in daily life health assessment. Consequently, this study seeks to validate an algorithm for the classification of daily life activities and to provide a detailed gait analysis in older adults. A system consisting of an inertial sensor combined with a pressure sensing insole has been developed. Using an algorithm that we previously validated during a semi structured protocol, activities in 10 healthy elderly participants were recorded and compared to a wearable reference system over a 4 h recording period at home. Detailed gait parameters were calculated from inertial sensors. Dynamics of physical behavior were characterized using barcodes that express the measure of behavioral complexity. Activity classification based on the algorithm led to a 93% accuracy in classifying basic activities of daily life, i.e., sitting, standing, and walking. Gait analysis emphasizes the importance of metrics such as foot clearance in daily life assessment. Results also underline that measures of physical behavior and gait performance are complementary, especially since gait parameters were not correlated to complexity. Participants gave positive feedback regarding the use of the instrumented shoes. These results extend previous observations in showing the concurrent validity of the instrumented shoes compared to a body-worn reference system for daily-life physical behavior monitoring in older adults. PMID:27527172

  18. Regional plantar foot pressure distributions on high-heeled shoes-shank curve effects

    Institute of Scientific and Technical Information of China (English)

    Yan Cong; Winson Lee; Ming Zhang

    2011-01-01

    Forefoot pain is common in high-heeled shoe wearers due to the high pressure caused by the center of body mass moving forward and the increased arch height with heel elevation.Sufficient arch support could reduce the high pressure over forefoot.However,too much arch support could lead to abnormal foot alignment and pain over midfoot.Little information is reported on the relationship among plantar arch height,shank curve design and plantar pressure.This study aimed at quantifying the plantar arch height changes at different heel heights and investigating the effect of shank curve on plantar pressure distribution.The plantar arch height increased to (7.6+1.3)mm at heel height of 75 mm.The Chinese standard suggests the depth of last should be 8.5 mm for heel height of 75 mm.When a shank curve with higher depth of last (11 mm) was used,the peak pressure over forefoot further decreased in midstance phase,which might ease the forefoot problems,while the peak pressure over midfoot increased but not exceeded the discomfort pressure thresholds.To achieve a more ideal pressure distribution in high-heeled shoes,a higher than expected depth of last would be suggested that would not cause discomfort over midfoot.

  19. Work-related depression and associated factors in a shoe manufacturing factory in Haiphong City, Vietnam

    Directory of Open Access Journals (Sweden)

    Khue Pham Minh

    2014-12-01

    Full Text Available Objectives: To determine the prevalence and associated factors of work-related depression among the employees of a shoe manufacturing factory in Haiphong City, Vietnam. Material and Methods: We carried out this cross-sectional study among 420 workers in 2012 in Le Lai II Shoe Manufacturing Factory in Haiphong City, Vietnam using Karasek’s Job Content Questionnaire (JCQ and the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM IV tool for measuring depression. Results: The study results show that a relatively high proportion of workers (20.7% belongs to the high-strain group based on Karasek’s model. The prevalence of work-related depression among workers was relatively high (18.8%. The factors associated with depression at work were high psychological demand (adjusted OR = 3.0, 95% CI: 1.1–8.3, low social support (adjusted OR = 4.7, 95% CI: 1.2–12.8, inadequate work protection materials (OR = 4.1, 95% CI: 2.2–10.1 and work absenteeism (OR = 6.2, 95% CI: 2.5–18.9. Conclusions: Strengthening the social support network (involving supervisors and co‑workers, reducing psychological job demand and assuring work protection materials at the workplace may highly facilitate reducing work-related depression.

  20. SPORTS SHOES PURCHASE INTENTION AMONG MALAYSIAN VOLLEYBALL PLAYERS VS. NON-VOLLEYBALL PLAYERS: A CONCEPTUAL PAPER

    Directory of Open Access Journals (Sweden)

    GOH PIN SIANG

    2013-12-01

    Full Text Available The purpose of this study is to advance the understanding of volleyball players’ purchase intention toward sport shoes by investigating the relationship between the independent variables (endorsement, advertising, pricing and electronic word-of-mouth and purchase intention. Descriptive research and causal research will be used as the research design, thus questionnaire and experimentation will be used to obtain data. Primary data in this study is attained by distributing the questionnaire to the Malaysian volleyball players throughout several volleyball tournament venues in Malaysia. The experiment will be conducted by comparing two groups of respondents, including volleyball players and non-volleyball players. This study is limited to several independent variables such as endorsement, advertising, pricing and electronic word-of-mouth. This study is significant for marketers for solving the challenges faced in the sport industry. It also helps to identify consumers’ purchase preferences for sport shoes. The marketer would understand more about their targeted customers’ intentions to purchase, thus the sport industry related with sport marketing in Malaysia might gain more profit.

  1. Redistribution and magnitude of stresses around horse shoe and circular excavations opened in anisotropic rock

    Institute of Scientific and Technical Information of China (English)

    Mambou Ngueyep Luc Leroy; Ndop Joseph; Ndjaka Jean-Marie Bienvenu

    2015-01-01

    In this paper numerical analysis of underground structures, taking account the transverse isotropy system of rocks, was done using CAST 3M code by varying the shape of excavation and the coefficient of earth pressure k. Numerical results reveal that the anisotropy behavior, the shape of hole and the coefficient of earth pressure k have significant influence to the mining induced stress field and rock deformations which directly control the stability of underground excavation design. The magnitude of horizontal stress obtained for the horse shoe shape excavation (25.2 MPa for k=1; 52.7 MPa for k=2) is lower than the magnitude obtained for circular hole (26.4 MPa for k=1; 59.5 MPa for k=2). Therefore, we have concluded that the horse shoe shape offers the best stability and the best design for engineer. The anisotropy system presented by rock mass can also influence the redistribution of stresses around hole opened. Numerical results have revealed that the magnitude of redistribution of horizontal stresses obtained for transverse isotropic rock (12.1 MPa for k=0.5; 25.2 MPa for k=1 and 52.7 MPa for k=2) is less than those obtained in the case of isotropic rock (27.6 MPa for k=1;48.6 MPa for k=2 and 90.81 MPa for k=2). The more the rock has the anisotropic behavior, the more the mass of rock around the tunnel is stable.

  2. Detecting groan sources in drum brakes of commercial vehicles by TVA-FMEA

    OpenAIRE

    Karabay, Sedat; Baynal, Kasim; İğdeli, Cengiz

    2015-01-01

    In this article, the strategy followed by an automobile company for detecting the root causes of groan complaints related to rear drum brakes in commercial vehicles is presented using data collected from the sold troubled vehicles and from new vehicles from the production line, as well as the drum-brake test rig at the laboratory. Drum brake groan is often very intense and can cause large numbers of customer complaints. During a groan noise event, vehicle structure and suspension components a...

  3. Detecting groan sources in drum brakes of commercial vehicles by TVA-FMEA: a case study:

    OpenAIRE

    Baynal, Kasim; Igdeli, Cengiz; Karabay, Sedat

    2013-01-01

    In this article, the strategy followed by an automobile company for detecting the root causes of groan complaints related to rear drum brakes in commercial vehicles is presented using data collected from the sold troubled vehicles and from new vehicles from the production line, as well as the drum-brake test rig at the laboratory. Drum brake groan is often very intense and can cause large numbers of customer complaints. During a groan noise event, vehicle structure and suspension components a...

  4. Studies on Horizontal Axis Wind Turbine with Passive Teetered Brake & Damper Mechanism

    OpenAIRE

    Shimizu, Yukimaru; KAMADA, Yasunari; MAEDA, Takao

    1998-01-01

    In order to improve the reliability of megawatt wind turbines, the passive teetered brake & damper mechanism is applied. Its two unique effects, as its name implies, are braking and damping. The passive brake & damper mechanism is useful for variable speed control of the large wind turbine. It is comprised of teetering and feathering mechanisms. When the wind speed exceeds the rated wind speed, the blade is passively teetered in a downwind direction and, at the same time, a feathering mechani...

  5. 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 ...

  6. Design of a squeeze film magnetorheological brake considering compression enhanced shear yield stress of magnetorheological fluid

    Science.gov (United States)

    Sarkar, C.; Hirani, H.

    2013-02-01

    A magnetorheological brake, consisting of rotating disks immersed in a MR fluid and enclosed in an electromagnet, is proposed to replace the conventional heavy weight low response hydraulic disk brake. The frictional characteristics of the proposed brake can be controlled by regulating the yield stress of the MR fluid as function of magnetic field and normal compressive force. The controllable yield stress retards the surfaces of rotating disks, thus MR fluid can be used as a brake lining material. The present research work attempts designing a squeeze film MR brake by accounting compression enhanced shear yield stress of magnetorheological fluid. Theoretical calculations indicate that the estimated braking torque of the six plate squeeze film MR brake, under compression, is in the order of 600Nm. To validate the theoretical design and its findings, a prototype of single-plate squeeze film MR disk brake has been developed. Experimental test setup helps to illustrate braking torque under different control currents (0.0 to 1.25 A).

  7. Analysis of the stability of PTW riders in autonomous braking scenarios.

    Science.gov (United States)

    Symeonidis, Ioannis; Kavadarli, Gueven; Erich, Schuller; Graw, Matthias; Peldschus, Steffen

    2012-11-01

    While fatalities of car occupants in the EU decreased remarkably over the last decade, Powered Two Wheelers (PTWs) fatalities still increase following the increase of PTW ownership. Autonomous braking systems have been implemented in several types of vehicles and are presently addressed by research in the field of PTWs. A major concern in this context is the rider stability. Experiments with volunteers were performed in order to find out whether autonomous braking for PTWs will produce a greater instability of the rider in comparison to manual braking. The PTW's braking conditions were simulated in a laboratory with a motorcycle mock-up mounted on a sled, which was accelerated with an average of 0.35 g. The motion of the rider was captured in autonomous braking scenarios with and without pre-warning as well as in manual braking scenarios. No significant differences between the scenarios were found with respect to maximum forward displacement of the volunteer's torso and head (pautonomous braking at low deceleration will not cause significant instabilities of the rider in comparison to manual braking in idealized laboratory conditions. Based on this, further research into the development and implementation of autonomous braking systems for PTWs, e.g. by extensive riding tests, seems valuable.

  8. Real-Time Dynamic Brake Assessment Proof of Concept Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Lascurain, Mary Beth [ORNL; Franzese, Oscar [ORNL; Capps, Gary J [ORNL

    2011-11-01

    This proof-of-concept research was performed to explore the feasibility of using real-world braking data from commercial motor vehicles to make a diagnosis of brake condition similar to that of the performance-based brake tester (PBBT). This was done by determining the relationship between pressure and brake force (P-BF), compensating for the gross vehicle weight (GVW). The nature of this P-BF relationship (e.g., low braking force for a given brake application pressure) may indicate brake system problems. In order to determine the relationship between brake force and brake application pressure, a few key parameters of duty cycle information were collected. Because braking events are often brief, spanning only a few seconds, a sample rate of 10 Hz was needed. The algorithm under development required brake application pressure and speed (from which deceleration was calculated). Accurate weight estimation was also needed to properly derive the braking force from the deceleration. In order to ensure that braking force was the predominant factor in deceleration for the segments of data used in analysis, the data was screened for grade as well. Also, the analysis needed to be based on pressures above the crack pressure. The crack pressure is the pressure below which the individual brakes are not applied due the nature of the mechanical system. This value, which may vary somewhat from one wheel end to another, is approximately 10 psi. Therefore, only pressures 15 psi and above were used in the analysis. The Department of Energy s Medium Truck Duty Cycle research has indicated that under the real-world circumstances of the test vehicle brake pressures of up to approximately 30 psi can be expected. Several different types of data were collected during the testing task of this project. Constant-pressure stopping tests were conducted at several combinations of brake application pressure (15, 20, 25, and 30 psi), load conditions (moderately and fully laden), and speeds (20 and

  9. 重载列车制动管路对制动性能的影响%Influence of braking pipe on braking performance for heavy haul train

    Institute of Scientific and Technical Information of China (English)

    魏伟; 杜念博

    2011-01-01

    应用流体动力学理论,建立了重载列车制动管路模型与分配阀模型,求解了制动管路和边界点的动力学方程,仿真计算了制动过程中的制动系统性能,分析了列车主管和支管长度对制动系统性能的影响。分析结果表明:当列车主管长度由13.24 m增大为17.24 m时,在常用制动下,列车管路减压时间增大了30.75%,制动缸升压时间增大了20.45%,主管长度对常用制动的影响要强于对紧急制动的影响;当列车支管长度由0.50 m增大到5.00 m时,在常用制动下,列车管路减压时间增大了6.63%,制动缸升压时间增大了5.22%,支管长度对常用制动和紧急制动影响程度差别不大。列车制动管路长度增大降低了列车制动管路减压速度与制动缸升压速度;列车主管长度对制动性能的影响要明显大于列车支管长度的影响,车辆位置距机车越远影响越明显。%With fluid dynamics theory,the models of braking pipe and distributing valve for heavy haul train were built,the equations of braking pipe and boundary point were solved,the braking system performances in braking process were simulated,and the influence of the lengths of main pipe and branch pipe on the braking performances was analyzed.Analysis result shows that under common braking,when the length of main pipe increases from 13.24 m to 17.24 m,the decompression time of braking pipe increases by 30.75%,and the boost time of braking cylinder increases by 20.45%.The influence of main pipe on common braking is even stronger than that of main pipe on emergency braking.Under common braking,when the length of branch pipe increases from 0.50 m to 5.00 m,the decompression time of braking pipe increases by 6.63%,and the boost time of braking cylinder increases by 5.22%.The influence of branch pipe on common braking is almost same for that of branch pipe on emergency braking.The increase length of braking pipe reduces the decompression speed of braking pipe

  10. A Computational Study on the Use of an Aluminium Metal Matrix Composite and Aramid as Alternative Brake Disc and Brake Pad Material

    Directory of Open Access Journals (Sweden)

    Nosa Idusuyi

    2014-01-01

    Full Text Available A computational model for the heat generation and dissipation in a disk brake during braking and the following release period has been formulated. The model simulates the braking action by investigating the thermal behaviour occurring on the disc and pad surfaces during this period. A comparative study was made between grey cast iron (GCI, asbestos, Aluminium metal matrix composite (AMC, and aramid as brake pad and disc materials. The braking process and following release period were simulated for four material combinations, GCI disc and Asbestos pad, GCI disc and Aramid pad, AMC disc and Asbestos pad, AMC disc and Aramid pad using COMSOL Multiphysics software. The results show similarity in thermal behaviour at the contact surface for the asbestos and aramid brake pad materials with a temperature difference of 1.8 K after 10 seconds. For the brake disc materials, the thermal behaviour was close, with the highest temperature difference being 9.6 K. The GCI had a peak temperature of 489 K at 1.2 seconds and AMC was 465.5 K but cooling to 406.4 K at 10 seconds, while the GCI was 394.7 K.

  11. A method to investigate the effect of shoe-hole size on surface marker movement when describing in-shoe joint kinematics using a multi-segment foot model.

    Science.gov (United States)

    Bishop, Chris; Arnold, John B; Fraysse, Francois; Thewlis, Dominic

    2015-01-01

    To investigate in-shoe foot kinematics, holes are often cut in the shoe upper to allow markers to be placed on the skin surface. However, there is currently a lack of understanding as to what is an appropriate size. This study aimed to demonstrate a method to assess whether different diameter holes were large enough to allow free motion of marker wands mounted on the skin surface during walking using a multi-segment foot model. Eighteen participants underwent an analysis of foot kinematics whilst walking barefoot and wearing shoes with different size holes (15 mm, 20mm and 25 mm). The analysis was conducted in two parts; firstly the trajectory of the individual skin-mounted markers were analysed in a 2D ellipse to investigate total displacement of each marker during stance. Secondly, a geometrical analysis was conducted to assess cluster deformation of the hindfoot and midfoot-forefoot segments. Where movement of the markers in the 15 and 20mm conditions were restricted, the marker movement in the 25 mm condition did not exceed the radius at any anatomical location. Despite significant differences in the isotropy index of the medial and lateral calcaneus markers between the 25 mm and barefoot conditions, the differences were due to the effect of footwear on the foot and not a result of the marker wands hitting the shoe upper. In conclusion, the method proposed and results can be used to increase confidence in the representativeness of joint kinematics with respect to in-shoe multi-segment foot motion during walking.

  12. Shoe Giant

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    ShoeGiantByYANGDALITHEcityofWenzhouinZhejiangProvinceisChi-na'sshoecapital.AmongthemillionsofshoesproduceddailybyWenzhou'smor...

  13. Footloose Shoes?

    DEFF Research Database (Denmark)

    Lorentzen, Jochen

    2003-01-01

    ABSTRACTThe paper analyses the effect on manufacturers in Italy's footwear districts of international competition, and investigates the underresearched nature of the link between international competition and the internal cohesion of districts. It addresses if and how global competition provokes ...

  14. Car Shoe

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    历史悠久的意大利制鞋商Car Shoe为日本爱知世界博览会意大利展团迎宾小姐设计的两款皮鞋,轻松休闲又不失高雅,完美再现Car Shoe的设计理念,其中一款舒适大方“Driving”软底鞋,白1963年上市至今,始终风靡全球,成为一代经典。布满黑色胶皮钉的鞋底,是Car Shoe鞋子的标志性特点,另有一款3.5厘米的矮跟 鞋,尽显女性独特魅力。

  15. Footloose Shoes?

    OpenAIRE

    Lorentzen, Jochen

    2003-01-01

    ABSTRACT The paper analyses the effect on manufacturers in Italy’s footwear districts of international competition, and investigates the underresearched nature of the link between international competition and the internal cohesion of districts. It addresses if and how global competition provokes the (partial) geographic fragmentation of local supply chains, dislocating select local parts manufacturers in its wake. The findings suggest that when international competition threatens the viab...

  16. Effects of Shoe Heel Height on Loading and Muscle Activity for Trans-Tibial Amputees During Standing

    Institute of Scientific and Technical Information of China (English)

    JIA Xiaohong; WANG Rencheng; Winson Lee

    2009-01-01

    This study accesses the effects of shoe heel heights on loading, muscle activity, and plantar foot pressure of trans-tibial amputees during standing. Five male subjects with unilateral trans-tibial amputation volunteered to participate in this study. Three pairs of shoes with zero, 20 mm, and 40 mm heel heights were used. The loading line of the prosthetic side, the plantar foot pressure, and the surface electromyography (EMG) of 10 muscles were simultaneously recorded. With increasing shoe heel heights during standing, the loading line of the prosthetic side shifted from the anterior to the posterior side of the knee center, the peak pressure was increased in the medial forefoot region, and the peak pressure was reduced in the heel region. The EMG of the medial and lateral gastrocnemius of the sound leg almost doubled and that of the rectus fomris, vastus lateralis, and vastus medialis of the prosthetic side increased to different extents with in-creasing heel heights from zero to 40 mm. These results show a high correlation with human physical be-havior. Changing of the heel heights for trans-tibial amputees during standing actually had similar effects to altering the prosthetic sagittal alignment. The results suggest that an alignment change is necessary to ac-commodate heel height changes and that prosthesis users should be cautious when choosing shoes.

  17. Evaluation and optimization of therapeutic footwear for neuropathic diabetic foot patients using in-shoe plantar pressure analysis

    NARCIS (Netherlands)

    S.A. Bus; R. Haspels; T.E. Busch-Westbroek

    2011-01-01

    Therapeutic footwear for diabetic foot patients aims to reduce the risk of ulceration by relieving mechanical pressure on the foot. However, footwear efficacy is generally not assessed in clinical practice. The purpose of this study was to assess the value of in-shoe plantar pressure analysis to eva

  18. Questionnaire for usability evaluation of orthopaedic shoes : Construction and reliability in patients with degenerative disorders of the foot

    NARCIS (Netherlands)

    Jannink, MJA; de Vries, J; Stewart, RE; Groothoff, JW; Lankhorst, GJ

    2004-01-01

    Objective: To develop a self-report questionnaire for patients with degenerative disorders of the foot to evaluate the usability of their orthopaedic shoes, and to assess the reproducibility and responsiveness of the instrument. Design: Development of the Questionnaire for Usability Evaluation of or

  19. Questionnaire for usability evaluation of orthopaedic shoes: construction and reliability in patients with degenerative disorders of the foot

    NARCIS (Netherlands)

    Jannink, Michiel J.A.; Vries, de Jaap; Stewart, Roy E.; Groothoff, Johan W.; Lankhorst, Gustaaf J.

    2004-01-01

    Objective: To develop a self-report questionnaire for patients with degenerative disorders of the foot to evaluate the usability of their orthopaedic shoes, and to assess the reproducibility and responsiveness of the instrument. Design: Development of the Questionnaire for Usability Evaluation of or

  20. The effect of different types of insoles or shoe modifications on medial loading of the knee in persons with medial knee osteoarthritis: a randomised trial.

    Science.gov (United States)

    Jones, Richard K; Chapman, Graham J; Parkes, Matthew J; Forsythe, Laura; Felson, David T

    2015-11-01

    Many conservative treatments exist for medial knee osteoarthritis (OA) which aims to reduce the external knee adduction moment (EKAM). The objective of this study was to determine the difference between different shoes and lateral wedge insoles on EKAM, knee adduction angular impulse (KAAI), external knee flexion moment, pain, and comfort when walking in individuals with medial knee OA. Seventy individuals with medial knee OA underwent three-dimensional walking gait analysis in five conditions (barefoot, control shoe, typical wedge, supported wedge, and mobility shoe) with pain and comfort recorded concurrently. The change in EKAM, KAAI, external knee flexion moment, pain, and comfort were assessed using multiple linear regressions and pairwise comparisons. Compared with the control shoe, lateral wedge insoles and barefoot walking significantly reduced early stance EKAM and KAAI. The mobility shoe showed no effect. A significant reduction in latter stance EKAM was seen in the lateral wedge insoles compared to the other conditions, with only the barefoot condition reducing the external knee flexion moment. However, the mobility shoe showed significant immediate knee pain reduction and improved comfort scores. Different lateral wedge insoles show comparable reductions in medial knee loading and in our study, the mobility shoe did not affect medial loading.

  1. Treatment of Forefoot Problems in Older People: A Randomized Clinical Trial Comparing Podiatric Treatment With Standardized Shoe Advice

    Science.gov (United States)

    van der Zwaard, Babette C.; van der Horst, Henriëtte E.; Knol, Dirk L.; Vanwanseele, Benedicte; Elders, Petra J. M.

    2014-01-01

    PURPOSE Consultations for forefoot pain are frequent in primary care, but scientific support of treatment options is scarce. The purpose of this study is to investigate the effect of podiatric treatment vs standardized advice on proper shoe characteristics and fit of shoes by means of an information leaflet for people aged 50 years and older with forefoot pain in primary care. METHODS In this randomized controlled trial, 205 participants aged 50 years and older with hindering nontraumatic forefoot pain have been recruited at their general practitioner’s office. Exclusion criteria were treatment of forefoot problem of less than 6 months’ duration before inclusion, rheumatoid arthritis, and diabetic neuropathy or having pain considered not to be musculoskeletal (eg, warts). Participants received shoe advice by means of an information leaflet or podiatric care. Foot pain, foot-related dysfunction, general health, and social participation were assessed by means of questionnaires every 3 months for 1 year. Using multilevel analysis, we analyzed results at the level of (1) outcome measures, (2) the individual, and (3) the general practitioner. RESULTS No differences were found between the 2 treatment groups. Both intervention groups showed an improvement over time in foot pain and foot-related dysfunction. CONCLUSION This study found that shoe advice provided to patients consulting their general practitioner for forefoot pain and symptom relief resulted in outcomes similar to treatment outcomes in patients consulting a podiatrist. Based on these results, primary care physicians should be cautious when referring a patient to a podiatrist; instead, they should start by providing advice on proper characteristics and fit of shoes. PMID:25354407

  2. Value generation in the context of manufacturing strategy: an analysis in shoe manufactories

    Directory of Open Access Journals (Sweden)

    Sergio Evangelista Silva

    2015-02-01

    Full Text Available The manufacturing function has the role of provide to the customers products with generate value. However this task is not unique of this function, it has to work with the functions research and development (R&D and marketing and sales (M&S. This paper call these three functions as generating value functions, and discuss their mutual role in the process of generating value in the products of a firm. The validation of this model is performed by three comparative case studies, conducted in three shoe manufactories (SMs, with different value generation strategies. The empirical study shows that the mutual role of generating value functions in the value generating process, and that the configuration and the relative role of each function change according to the firm strategy followed.

  3. Patch Testing With Shoe Series In Suspected Cases Of Footwear Dermatitis

    Directory of Open Access Journals (Sweden)

    Eapen Bell Raj

    2001-01-01

    Full Text Available One hundred fifty nine patients with clinically suspected footwear dermatitis were patch tested to determine the frequency of positivity of common footwear antigens. Patch testing was done with 22 allergens of Shoe series (Chemotechnique Diagnostics AB Sweden extended with neomycin, gentamycin, soframycin, paraben, cresol and lanolin. Forty- two percent of patients was sensitive to footwear allergen(s whereas the overall positivity was 62%. Potassium dichromate. 2 mercapto- benzothiazole (MBT and nickel sulphate were the frequent sensitizers followed by gentamycin, neomycin, gluteraldehyde, formaldehyde, diphenyl guanidine, diphenyl thiourea, dibutyl thiourea, para-tertiary butyl phenol and 4 aminoazobenzene. Dorsa of feet was the commonest site. potassium dichromate sensitivity was higher in males and the history was not always helpful in incriminating the antigen.

  4. The influence of store image on customer satisfaction: a case study of a shoe store

    Directory of Open Access Journals (Sweden)

    Tarsis Souza Silva

    2010-01-01

    Full Text Available Knowledge of customers' image of a store is an essential factor in the management of retail outlets. This article presents a case study of the effect of the image customers have of a shoe store on their satisfaction, based on a descriptive and quantitative survey, with the application of a structured questionnaire. We then employed factor analysis to obtain seven store image factors: assortment, convenience, reputation, price, atmosphere, layout and service. The results show that the factor that most affects customer satisfaction in the store studied is service, and that atmosphere and layout have no effect in this respect. The results provide a better understanding of the role store image plays in customer satisfaction and loyalty.

  5. Modified distal shoe appliance for the loss of a primary second molar: a case report.

    Science.gov (United States)

    Dhull, Kanika Singh; Bhojraj, Nandlal; Yadav, Shweta; Prabhakaran, Sheeja Devi

    2011-01-01

    Preservation of primary teeth until their normal exfoliation plays a crucial role in preventive and interceptive dentistry. Premature loss of the primary second molar prior to the eruption of the permanent first molar in the absence of the primary second molar can lead to mesial movement and migration of the permanent molar before and during its eruption. In such cases, an intra-alveolar type of space maintainer to guide the eruption of the permanent first molar is indicated. In certain cases, however, the conventional design is not practical. This paper describes a new design for distal shoe appliances in cases of primary second molar loss prior to the eruption of the permanent mandibular first molar.

  6. Nasal cancer in the Northamptonshire boot and shoe industry: is it declining?

    Science.gov (United States)

    Acheson, E D; Pippard, E C; Winter, P D

    1982-12-01

    This paper reports a survey of nasal cancer in Northamptonshire during the period 1950-79. An increased risk of various histological types of nasal tumour has been observed within the footwear manufacturing industry, which seems to be limited to the minority of men and women exposed to the dust of leather soles and heels. In Northamptonshire this exposure has usually occurred in the preparation, press and finishing rooms of factories making boots and shoes by the welted process. This type of leather is tanned by treatment with vegetable extracts, not chrome salts. Although the population of workers involved has diminished over the period of the study there has been no evidence of a decline in incidence of these tumours within it. PMID:7150487

  7. Harvested power and sensitivity analysis of vibrating shoe-mounted piezoelectric cantilevers

    Science.gov (United States)

    Moro, L.; Benasciutti, D.

    2010-11-01

    This paper presents a preliminary investigation on energy harvesting from human walking via piezoelectric vibrating cantilevers. Heel accelerations during human gait are established by correlating data gathered from the literature with direct experimental measurements. All the observed relevant features are synthesized in a typical (standard) acceleration signal, used in subsequent numerical simulations. The transient electromechanical response and the harvested power of a shoe-mounted bimorph cantilever excited by the standard acceleration signal is computed by numerical simulations and compared with measurements on a real prototype. A sensitivity analysis is finally developed to estimate the mean harvested power for a wide range of scavenger configurations. Acceptability criteria based on imposed geometrical constraints and resistance strength limits (e.g. fatigue limit) are also established. This analysis allows a quick preliminary screening of harvesting performance of different scavenger configurations.

  8. Analysis of walking improvement with dynamic shoe insoles, using two accelerometers

    Science.gov (United States)

    Tsuruoka, Yuriko; Tamura, Yoshiyasu; Shibasaki, Ryosuke; Tsuruoka, Masako

    2005-07-01

    The orthopedics at the rehabilitation hospital found that disorders caused by sports injuries to the feet or caused by lower-back are improved by wearing dynamic shoe insoles, these improve walking balance and stability. However, the relationship of the lower-back and knees and the rate of increase in stability were not quantitatively analyzed. In this study, using two accelerometers, we quantitatively analyzed the reciprocal spatiotemporal contributions between the lower-back and knee of patients with left lower-back pain by means of Relative Power Contribution Analysis. When the insoles were worn, the contribution of the left and right knee relative to the left lower-back pain was up to 26% ( panalysis of the left and right knee decreased by up to 67% ( p<0.05). This shows an increase in stability.

  9. Research on Extraction of Bottom of Shoe Pattern Based on Binocular Stereo Vision

    Institute of Scientific and Technical Information of China (English)

    MA Xin-wu; GAN Yi; SUN Fu-jia

    2016-01-01

    In order to quickly and efficiently get the information of the bottom of the shoe pattern and spraying trajectory, the paper proposes a method based on binocular stereo vision .After acquiring target image , edge detection based on the canny algorithm , the paper begins stereo matching based on area and characteristics of algorithm.To eliminate false matching points , the paper uses the principle of polar geometry in computer vision . For the purpose of gaining the 3D point cloud of spraying curve , the paper adopts the principle of binocular stereo vision 3D measurement , and then carries on cubic spline curve fitting .By HALCON image processing software programming , it proves the feasibility and effectiveness of the method .

  10. Product Quality Improvement Using FMEA for Electric Parking Brake (EPB)

    Science.gov (United States)

    Dumitrescu, C. D.; Gruber, G. C.; Tişcă, I. A.

    2016-08-01

    One of the most frequently used methods to improve product quality is complex FMEA. (Failure Modes and Effects Analyses). In the literature various FMEA is known, depending on the mode and depending on the targets; we mention here some of these names: Failure Modes and Effects Analysis Process, or analysis Failure Mode and Effects Reported (FMECA). Whatever option is supported by the work team, the goal of the method is the same: optimize product design activities in research, design processes, implementation of manufacturing processes, optimization of mining product to beneficiaries. According to a market survey conducted on parts suppliers to vehicle manufacturers FMEA method is used in 75%. One purpose of the application is that after the research and product development is considered resolved, any errors which may be detected; another purpose of applying the method is initiating appropriate measures to avoid mistakes. Achieving these two goals leads to a high level distribution in applying, to avoid errors already in the design phase of the product, thereby avoiding the emergence and development of additional costs in later stages of product manufacturing. During application of FMEA method using standardized forms; with their help will establish the initial assemblies of product structure, in which all components will be viewed without error. The work is an application of the method FMEA quality components to optimize the structure of the electrical parking brake (Electric Parching Brake - E.P.B). This is a component attached to the roller system which ensures automotive replacement of conventional mechanical parking brake while ensuring its comfort, functionality, durability and saves space in the passenger compartment. The paper describes the levels at which they appealed in applying FMEA, working arrangements in the 4 distinct levels of analysis, and how to determine the number of risk (Risk Priority Number); the analysis of risk factors and established

  11. Parameter Analysis on Torque Stabilization for the Eddy Current Brake: A Developed Model, Simulation, and Sensitive Analysis

    OpenAIRE

    Quan Zhou; Xuexun Guo; Gangfeng Tan; Xiaomeng Shen; Yifan Ye; Zhaohua Wang

    2015-01-01

    Eddy current brake (ECB) is an attractive contactless brake whereas it suffers from braking torque attenuation when the rotating speed increases. To stabilize the ECB’s torque generation property, this paper introduces the concept of anti-magneto-motive force to develop the ECB model on the fundamental of magnetic circles. In the developed model, the eddy current demagnetization and the influence of temperature which make the braking torque attenuation are clearly presented. Using the develop...

  12. Comparing Variability of Parameters between Roller Bed Brakes Testers and Dynamometric Platform of Ministry Of Transport Facilities

    Directory of Open Access Journals (Sweden)

    Senabre C

    2015-01-01

    Full Text Available This study gives a comparison between which parameters may vary when braking on two different Ministry of Transport (MOT brake testers, such as roller bed brake tester and dynamometric platform. A comparative study between both types of brake testers have been carried out by the mechanical engineering staffs at the mechanical laboratory at the Miguel Hernández University in Elche to determinate which parameters can vary the result of the test.

  13. 77 FR 51649 - Federal Motor Vehicle Safety Standards; Motorcycle Brake Systems

    Science.gov (United States)

    2012-08-24

    ... passenger cars.\\7\\ \\6\\ Response to Petitions for Reconsideration, Motorcycle Brake Systems, 37 FR 11973... braking performance, they have not kept pace with the advancement of modern technologies. The National... reflects the capabilities of current in-use technologies. Updating the standard to reflect...

  14. 49 CFR 571.135 - Standard No. 135; Light vehicle brake systems.

    Science.gov (United States)

    2010-10-01

    ... Federal Motor Vehicle Safety Standards § 571.135 Standard No. 135; Light vehicle brake systems. S1. Scope... driving conditions. S3. Application. This standard applies to passenger cars manufactured on or after... Vehicle No. 105, Hydraulic Brake Systems. S4. Definitions. Adhesion utilization curves means...

  15. 49 CFR 571.122 - Standard No. 122; Motorcycle brake systems.

    Science.gov (United States)

    2010-10-01

    ... conditions. S3. Application. This standard applies to motorcycles. S4. Definitions. Braking interval means... Federal Motor Vehicle Safety Standards § 571.122 Standard No. 122; Motorcycle brake systems. S1. Scope... the sequence specified in S7. Corresponding test procedures of S7 are indicated in parentheses. If...

  16. 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...

  17. INVESTIGATION OF ANTILOCK BRAKE SYSTEM EFFECT ON PASSENGER CAR BRAFKING EFFICIENCY

    Directory of Open Access Journals (Sweden)

    I. Davidenko

    2011-01-01

    Full Text Available It has been experimentally proved that in case of emergency braking the constant decelera-tion of passenger cars equipped by antilock brake system exceeds the tabulated statistical data by 7,7–17 % that is recommended to apply at technical expertise at traffic accident causes investigation.

  18. A New Model of Stopping Sight Distance of Curve Braking Based on Vehicle Dynamics

    Directory of Open Access Journals (Sweden)

    Rong-xia Xia

    2016-01-01

    Full Text Available Compared with straight-line braking, cornering brake has longer braking distance and poorer stability. Therefore, drivers are more prone to making mistakes. The braking process and the dynamics of vehicles in emergency situations on curves were analyzed. A biaxial four-wheel vehicle was simplified to a single model. Considering the braking process, dynamics, force distribution, and stability, a stopping sight distance of the curve braking calculation model was built. Then a driver-vehicle-road simulation platform was built using multibody dynamic software. The vehicle test of brake-in-turn was realized in this platform. The comparison of experimental and calculated values verified the reliability of the computational model. Eventually, the experimental values and calculated values were compared with the stopping sight distance recommended by the Highway Route Design Specification (JTGD20-2006; the current specification of stopping sight distance does not apply to cornering brake sight distance requirements. In this paper, the general values and limits of the curve stopping sight distance are presented.

  19. Brake wear from vehicles as an important source of diffuse copper pollution

    NARCIS (Netherlands)

    Hulskotte, J.H.J.; Gon, H.A.C.D. van der; Visschedijk, A.J.H.; Schaap, M.

    2007-01-01

    In this article we show that brake wear from road traffic vehicles is an important source of atmospheric (participate) copper concentrations in Europe. Consequently, brake wear also contributes significantly to deposition fluxes of copper to surface waters. We estimated the copper emission due to br

  20. 49 CFR 232.609 - Handling of defective equipment with ECP brake systems.

    Science.gov (United States)

    2010-10-01

    ... or locomotive equipped with an ECP brake system that is found with inoperative or ineffective brakes...; provided, all applicable provisions of this section are met and the defective car or locomotive is hauled... appliance may be used or hauled without civil penalty under this part to the nearest or nearest...

  1. Evolution of the pulsar inclination angle in the wind braking model

    CERN Document Server

    Kou, F F; Wang, N

    2016-01-01

    In a plasma filled magnetosphere, in addition to providing a torque to brake down the pulsar, the magnetosphere will also generate a torque to align the pulsar magnetic and rotational axes. The evolution of pulsar inclination angle in the wind braking model is calculated. In the wind braking model, the oblique pulsar tends to align. The pulsar alignment will also affect the spin-down behavior. Braking index will increase firstly and then decrease as the pulsar evolving from the magneto-dipole radiation dominated case to the wind braking dominated case. Braking index may be larger than $3$ in the early time. And during the following long time, braking index will be always smaller than $3$. This can explain braking index observations of larger than $3$ and smaller than $3$. Besides, the pulsar will evolve downwards straightly to the death valley after pulsar death in the $P-\\dot{P}$ diagram. This may explain the observed maximum spinning period of pulsars. And the long-term evolution of pulsars in the wind brak...

  2. 78 FR 44189 - Petition for Modification of Single Car Air Brake Test Procedures

    Science.gov (United States)

    2013-07-23

    ..., 2000 (65 FR 19477). Robert C. Lauby, Deputy Associate Administrator for Regulatory and Legislative... Federal Railroad Administration Petition for Modification of Single Car Air Brake Test Procedures In... the Federal Railroad Administration (FRA) per 49 CFR 232.307 to modify the single car air brake...

  3. Dynamic Control Applied to a Laboratory Antilock Braking System

    Directory of Open Access Journals (Sweden)

    Cuauhtémoc Acosta Lúa

    2015-01-01

    Full Text Available The control of an antilock braking system is a difficult problem due to the existence of nonlinear dynamics and uncertainties of its characteristics. To overcome these issues, in this work, a dynamic nonlinear controller is proposed, based on a nonlinear observer. To evaluate its performance, this controller has been implemented on an ABS Laboratory setup, representing a quarter car model. The nonlinear observer reconstructs some of the state variables of the setup, assumed not measurable, to establish a fair benchmark for an ABS system of a real automobile. The dynamic controller ensures exponential convergence of the state estimation, as well as robustness with respect to parameter variations.

  4. Dynamic Braking System of a Tidal Generator: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Muljadi, Eduard; Wright, Alan; Gevorgian, Vahan; Donegan, James; Marnagh, Cian; McEntee, Jarlath

    2016-08-01

    Renewable energy generation has experienced significant cost reductions during the past decades, and it has become more accepted by the global population. In the beginning, wind generation dominated the development and deployment of renewable energy; however, during recent decades, photovoltaic (PV) generation has grown at a very significant pace due to the tremendous decrease in the cost of PV modules. The focus on renewable energy generation has now expanded to include new types with promising future applications, such as river and tidal generation. The input water flow to these types of resources is more predictable than wind or solar generation. The data used in this paper is representative of a typical river or tidal generator. The analysis is based on a generator with a power rating of 40 kW. The tidal generator under consideration is driven by two sets of helical turbines connected to each side of the generator located in between the turbines. The generator is operated in variable speed, and it is controlled to maximize the energy harvested as well as the operation of the turbine generator. The electrical system consists of a three-phase permanent magnet generator connected to a three-phase passive rectifier. The output of the rectifier is connected to a DC-DC converter to match the rectifier output to the DC bus voltage of the DC-AC inverter. The three-phase inverter is connected to the grid, and it is controlled to provide a good interface with the grid. One important aspect of river and tidal generation is the braking mechanism. In a tidal generator, the braking mechanism is important to avoid a runaway condition in case the connection to the grid is lost when there is a fault in the lines. A runaway condition may lead to an overspeed condition and cause extreme stresses on the turbine blade structure and eventual disintegration of the mechanical structure. In this paper, the concept of the dynamic braking system is developed and investigated for normal

  5. MAGNETIC BRAKING AND FIELD DISSIPATION IN THE PROTOSTELLAR ACCRETION PHASE

    Directory of Open Access Journals (Sweden)

    D. Galli

    2009-01-01

    Full Text Available We summarize recent theoretical work addressing the role of magnetic elds in the process of star formation. First, we concentrate on the efficiency of magnetic braking during cloud collapse and its consequences on the formation of centrifugally supported disks around young stars. Then, we relate this issue to the well-known magnetic ux problem of star formation, and we show that the introduction of non-ideal MHD e ects is a necessary step toward the development of self-consistent models for the collapse of molecular clouds and the formation and evolution of accretion disks around young stars.

  6. Auxiliary brakes for trucks : research into the behaviour of a tractor-semi-trailer combination during emergency breaking.

    NARCIS (Netherlands)

    Dijks, A. Blijswijk, W.A.M. van Genugten, J. van Meeke, G.J.M. & Schlösser, L.H.M.

    1976-01-01

    The purpose of the research was to obtain an insight into various secondary braking systems for goods vehicles. Practical tests were carried out with a tractor- semi-trailer combination. The performance of various split braking systems as well as spring brake actuators are shown. With nearly all of

  7. Distribution and Dissipation of Braking Power of Wet Multidisc Brake%湿式多片制动器制动能的分配和耗散

    Institute of Scientific and Technical Information of China (English)

    阎清东; 宿新东

    2000-01-01

    研究湿式多片制动器制动过程制动能的分配和耗散,确定制动器的热负荷及摩擦偶件间热流分布的状况. 结合车辆的制动过程提出制动能四次分配的概念,利用有限元法计算制动能的三次、四次分配. 紧急制动中湿式多片制动器制动能的三次、四次分配主要与摩擦偶件的材料有关;持续制动中制动器吸收的能量主要由冷却润滑油带走. 为研究摩擦副的失效及摩擦材料的适用性提供了依据.%To study the distribution and dissipation of braking power of wet multidisc brake and determine thermal load and thermal flux distribution between mated discs, the concept of distributing brake power four times was put forward. The third and the fourth distribution of brake power were calculated by using finite element(FE) software ANSYS. The third and the fourth distribution of wet multidisc brake are mainly related to material characteristics of discs during emergency braking, while most of the braking power is carried off during continuous braking. Basis is provided for further analysis of disc failure and applicability of different friction materials.

  8. Some effects of grooved runway configurations on aircraft tire braking traction under flooded runway conditions

    Science.gov (United States)

    Byrdsong, T. A.

    1973-01-01

    An experimental investigation was conducted to study the effect of grooved runway configurations on aircraft tire braking traction on flooded runway surfaces. The investigation was performed, utilizing size 49 x 17, type VII, aircraft tires with an inflation pressure of 170 lb per square inch at ground speeds up to approximately 120 knots. The results of this investigation indicate that when the runway is flooded, grooved surfaces provide better braking traction than an ungrooved surface and, in general, the level of braking traction was found to improve as the tire bearing pressure was increased because of an increase in the groove area of either the surface or the tire tread. Rounding the groove edges tended to degrade the tire braking capability from that developed on the same groove configuration with sharp edges. Results also indicate that braking friction coefficients for the test tires and runway surfaces decreased as ground speed was increased because of the hydroplaning effects.

  9. Effect of Road Adhesion Coefficient on Tractor-Semitrailer Cornering Braking Stability

    Science.gov (United States)

    Wang, Wei; Li, Chen; Tang, Geteng; Wang, Cheng

    A dynamic model of tractor-semitrailer cornering braking was established in this paper, and the accuracy of the model was verified by real vehicle test. By model simulation of the cornering braking process, different road adhesion coefficient such as 0.15, 0.3, 0.45, 0.6, 0.75 was chosen to analyzed the changing curve of braking distance, articulation angle, yaw rate and lateral acceleration when initial speed of tractor-semitrailer was 30km h. The result showed that the peak values of articulation angle, yaw rate and lateral acceleration gotten by simulation were the largest. On the road of road adhesion coefficient 0.15, distance of tractor-semitrailer cornering braking was the longest. On the road of road adhesion coefficient 0.75, distance of tractor-semitrailer cornering braking was the shortest and the peak values of articulation angle, yaw rate and lateral acceleration were small relatively.

  10. Study of heat transfer on front– and back-vented brake discs

    Directory of Open Access Journals (Sweden)

    Supachai Lakkam

    2013-12-01

    Full Text Available A brake disc plays an important role in the automotive industry since it concerns directly with safety. In order to develop proper heat ventilation a wide range of brake discs have been designed. Different types of physical brake disc geometries, as front- and back-vented brake discs, affect the heat ventilation directly. This is a vital factor of the brake’s capability. We recognized the importance of this circumstance and therefore attempted to create a test to investigate the temperature gradient of the brake disc in order to evaluate the coefficients of heat convection. The coefficients were modified by the change of temperature distribution in both brake discs under the forced heat convection in steady state conditions. However, the heat radiation value does not take into account that the heat convection is dominated by the physical geometry of the brake disc. To set up the experimental test for investigating the heat transfer by convection the JASO C406 standard is adopted. The experimental results in terms of heat convection coefficients are used in the numerical simulation via the finite element method in order to study the temperature diffusion and heat ventilation of front and back-vented brake discs. Conse-quently, the experimental results reveal that the overall heat convection coefficients of the front-vented brake disc are higher than these of the back-vented one. In other words the simulation yields that the front-vented brake disc allows stronger heat ventilation than its compared object, leading to larger temperature differences between outboard and inboard rotors, resulting in more thermal stress. This makes it more susceptible to be damaged during operation.

  11. 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%.

  12. A nonextensive view of the stellar braking indices

    CERN Document Server

    de Freitas, D B; Soares, B B; Silva, J R P

    2015-01-01

    The present work is based on a description for the angular mometum loss rate due to magnetic braking for main-sequence stars on the relationship between stellar rotation and age. In general, this loss rate denoted by $\\mathrm dJ/\\mathrm dt$ depends on angular velocity $\\Omega$ in the form $\\mathrm dJ/\\mathrm dt\\propto\\Omega^{q}$, where $q$ is a parameter extracted from nonextensive statistical mechanics. Already, in context of stellar rotation, this parameter is greater than unity and it is directly related to the braking index. For $q$ equal to unity, the scenario of saturation of the magnetic field is recovered, otherwise $q$ indicates an unsaturated field. This new approach have been proposed and investigated by de Freitas \\& De Medeiros for unsaturated field stars. In present work, we propose a nonextensive approach for the stellar rotational evolution based on the Reiners \\& Mohanthy model. In this sense, we developed a nonextensive version of Reiners \\& Mohanthy torque and also compare this ...

  13. FES-Assisted Walking with Spring Brake Orthosis: Simulation Studies

    Directory of Open Access Journals (Sweden)

    R. Jailani

    2011-01-01

    Full Text Available This paper presents a simulation of bipedal locomotion to generate stimulation pulses for activating muscles for paraplegic walking with wheel walker using functional electrical stimulation (FES with spring brake orthosis (SBO. A new methodology for paraplegic gait, based on exploiting natural dynamics of human gait, is introduced. The work is a first effort towards restoring natural like swing phase in paraplegic gait through a new hybrid orthosis, referred to as spring brake orthosis (SBO. This mechanism simplifies the control task and results in smooth motion and more-natural like trajectory produced by the flexion reflex for gait in spinal cord injured subjects. SBO can eliminate reliance on the withdrawal reflex and foot-ground clearance without extra upper body effort. The stored energy in the spring of SBO is used to replace stimulation pulses in knee flexion and reduce total required torque for the paraplegic walking with wheel walker. The study is carried out with a model of humanoid with wheel walker using the Visual Nastran (Vn4D dynamic simulation software. Stimulated muscle model of quadriceps is developed for knee extension. Fuzzy logic control (FLC is developed in Matlab/Simulink to regulate the muscle stimulation pulse-width required to drive FES-assisted walking gait and the computed motion is visualised in graphic animation from Vn4D. The simulation results show that SBO can be successfully used with FES for paraplegic walking with wheel walker with all the advantages discussed over the current hybrid orthoses available.

  14. Big brake singularity is accommodated as an exotic quintessence field

    Science.gov (United States)

    Chimento, Luis P.; Richarte, Martín G.

    2016-02-01

    We describe a big brake singularity in terms of a modified Chaplygin gas equation of state p =(γm-1 )ρ +α γmρ-n, accommodate this late-time event as an exotic quintessence model obtained from an energy-momentum tensor, and focus on the cosmological behavior of the exotic field, its kinetic energy, and the potential energy. At the background level the exotic field does not blow up, whereas its kinetic energy and potential both grow without limit near the future singularity. We evaluate the classical stability of this background solution by examining the scalar perturbations of the metric along with the inclusion of entropy perturbation in the perturbed pressure. Within the Newtonian gauge, the gravitational field approaches a constant near the singularity plus additional regular terms. When the perturbed exotic field is associated with α >0 the perturbed pressure and contrast density both diverge, whereas the perturbed exotic field and the divergence of the exotic field's velocity go to zero exponentially. When the perturbed exotic field is associated with α <0 the contrast density always blows up, but the perturbed pressure can remain bounded. In addition, the perturbed exotic field and the divergence of the exotic field's velocity vanish near the big brake singularity. We also briefly look at the behavior of the intrinsic entropy perturbation near the singular event.

  15. Digital Sliding Mode Control of Anti-Lock Braking System

    Directory of Open Access Journals (Sweden)

    MITIC, D. B.

    2013-02-01

    Full Text Available The control of anti-lock braking system is a great challenge, because of the nonlinear and complex characteristics of braking dynamics, unknown parameters of vehicle environment and system parameter variations. Using some of robust control methods, such as sliding mode control, can be a right solution for these problems. In this paper, we introduce a novel approach to design of ABS controllers, which is based on digital sliding mode control with only input/output measurements. The relay term of the proposed digital sliding mode control is filtered through digital integrator, reducing the chattering phenomenon in that way, and the additional signal of estimated modelling error is introduced into control algorithm to enhance the system steady-state accuracy. The given solution was verified in real experimental framework and the obtained results were compared with the results of implementation of two other digital sliding mode control algorithms. It is shown that it gives better system response, higher steady-state accuracy and smaller chattering.

  16. Structure Analysis at the Micro Iron Pour at Gray Brake

    Directory of Open Access Journals (Sweden)

    Melya D. Sebayang

    2012-01-01

    Full Text Available The use of gray cast iron brake drum as the material is the most appropriate choice, because it has properties which have good heat conductivity, hardness, toughness, good friction properties and the ability to absorb vibration. The purpose of this study to determine the ratio of the microstructure on both original material drum that is new and original drum ex-wear. With the aim of analysis is expected to be used as basis in planning the development of better vehicle brakes. Of all the test results it can be mentioned chemical composition of test results with the main alloying elements, to drum new original: C 4:13%, 2:51% Si, 0.15% S, 0.65% Mn, 0.0054% P, and the original drum ex-wear: C 4:13%, 2:17% Si, 0.15% S, 0.53% Mn, 0.0054% P. So the comparison of properties of the resulting structure after the testing process on each drum is the hardness and resistance to wear and tear on a new original drum better when compared with the original drum ex-wear.

  17. 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 ...

  18. Influence of Optimizing Brake Pads Structure on Brake Disc Temperature and Thermal Stress%优化结构闸片对制动盘温度及热应力的影响

    Institute of Scientific and Technical Information of China (English)

    农万华; 符蓉; 韩晓明

    2012-01-01

    为了研究列车制动产生摩擦热对制动盘的耐热疲劳性能的影响,分析了摩擦热流分布与闸片结构的关系,提出一种优化闸片摩擦块固定位置,达到改善制动盘摩擦热分布的方法,采用有限元软件ABAQUS对优化前后的闸片制动过程进行了数值模拟,结果表明:与闸片优化前相比,闸片优化后制动盘最高温度和热应力分别下降的17%和23%,沿制动盘径向分布更均匀.%In order to study the effects of friction heat generation on thermal fatigue performance of brake disc during train braking, the relationship between friction heat flux distribution and brake pad structure was discussed , and a method of optimizing the brake pad friction blocks to improve the distribution of friction heat on brake disc was proposed. By finite element software ABAQUS, the braking process using the optimized brake pads and non-optimized brake pads was simulated respectively. The results show that the temperature of the optimized brake disc brake pads are decreased and the radial distribution of the thermal stress is more uniform along the brake disc. The results show thai compared with the brake pads before optimization, the highest temperature and thermal stress of the optimized brake discs brake pads are decreased by 17% and 23% respectively.

  19. 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.

  20. Plugging Braking of Two-PMSM Drive in Subway Applications with Fault-Tolerant Operation

    Directory of Open Access Journals (Sweden)

    Adel A. obed

    2016-06-01

    Full Text Available The Permanent Magnet Synchronous Motor (PMSM is commonly used as traction motors in the electric traction applications such as in subway train. The subway train is better transport vehicle due to its advantages of security, economic, health and friendly with nature. Braking is defined as removal of the kinetic energy stored in moving parts of machine. The plugging braking is the best braking offered and has the shortest time to stop. The subway train is a heavy machine and has a very high moment of inertia requiring a high braking torque to stop. The plugging braking is an effective method to provide a fast stop to the train. In this paper plugging braking system of the PMSM used in the subway train in normal and fault-tolerant operation is made. The model of the PMSM, three-phase Voltage Source Inverter (VSI controlled using Space Vector Pulse Width Modulation technique (SVPWM, Field Oriented Control method (FOC for independent control of two identical PMSMs and fault-tolerant operation is presented. Simulink model of the plugging braking system of PMSM in normal and fault tolerant operation is proposed using Matlab/Simulink software. Simulation results for different cases are given.

  1. Evaluation the course of the vehicle braking process in case of hydraulic circuit malfunction

    Science.gov (United States)

    Szczypiński-Sala, W.; Lubas, J.

    2016-09-01

    In the paper, the results of the research were discussed, the aim of which was the evaluation of the vehicle braking performance efficiency and the course of this process with regard to the dysfunction which may occur in braking hydraulic circuit. As part of the research, on-road tests were conducted. During the research, the delay of the vehicle when braking was measured with the use of the set of sensors placed in the parallel and the perpendicular axis of the vehicle. All the tests were conducted on the same flat section of asphalt road with wet surface. Conditions of diminished tire-to-road adhesion were chosen in order to force the activity of anti-lock braking system. The research was conducted comparatively for the vehicle with acting anti-lock braking system and subsequently for the vehicle without the system. In both cases, there was a subsequent evaluation of the course of braking with efficient braking system and with the dysfunction of hydraulic circuit.

  2. Analisis Strategi Pemasaran Pada Usaha Sepatu Dan Sandal Kulit Skala Mikro (Studi Pada Usaha Dagang Boenoet Shoes)

    OpenAIRE

    Marpaung, Vandi Jufri

    2014-01-01

    Formulation and implementation of a marketing strategy is not only intended for large-scale effort. At the micro-scale business is actually very requires the formulation of marketing strategies in order to compete and constantly evolving. However, most micro-scale businesses have not paid special attention to this, one of which is UD. Boenoet Shoes. This business has been established since 1993, but until now has not been able to grow significantly as it has problems surrounding the formulati...

  3. Characterisation of Q and T steel pole shoes manufactured by sand casting; Charakterisierung mit Sandguss hergestellter Polschuhe aus verguetetem Stahl

    Energy Technology Data Exchange (ETDEWEB)

    Asensio-Lozano, J.; Alvarez-Antolin, J.F. [Oviedo Univ. (Spain). Dept. of Materials Science and Metallurgical Engineering; Panta-Mesones, J.T. [National Univ. of Trujillo, La Libertad (Peru). Faculty of Mines, Metallurgy and Materials; Vander-Voort, G.F. [Buehler Ltd., Lake Bluff, IL (United States)

    2008-04-15

    This paper presents a study of the microstructural and mechanical characterization of the GS 35 CrMoV 10 4 alloy employed in the manufacture of sand-cast pole shoes for 4-pole synchronous electric power generators working at a frequency of 60 Hz. In addition, the most appropriate treatment for ensuring compliance with the technical specifications defined in DIN Standard No. 1.7755 has been designed. (orig.)

  4. The Effect of Shoe Sole Tread Groove Depth on the Gait Parameters during Walking on Dry and Slippery Surface

    Directory of Open Access Journals (Sweden)

    SF Tabatabai Ghomshe

    2013-01-01

    Full Text Available Background: Prevention of slipping accidents requires provision of adequate friction through the use of suitable combinations of footwear and underfoot surfaces. Shoe sole tread groove is one of the important factors on friction coefficient during walking.Objective: To measure the effect of different shoe sole tread groove depths and different surfaces on the required quotient of friction (Q, heel strike velocity and occurrence time of ground reaction forces (GRF in stance phase during walking on slippery and dry surfaces.Methods: In this semi-experimental study, 22 healthy men were studied under different conditions. The studied independent variables were shoe groove depths (included 1, 2.5 and 5 mm and type of walking surface (dry and slippery. Biomechanical gait analysis was carried out with 396 single steps. Data were collected by motion analysis system and two force platform.Results: The occurrence time of GRF was significantly faster on dry surface than slippery surface (p<0.01. Q was significantly lower on slippery surface and with groove depths of 1 and 2.5 mm. The highest value of Q was observed with the deepest groove depth of 5 mm. Heel strike velocity did not differ significantly in the 6 conditions tested.Conclusion: Tread groove depth is a significant factor affecting the Q at the shoes-surface interface on dry and slippery floors. It seems that deeper groove is more appropriate for maintaining the stability during walking. The walking surface affects the occurrence time of GRF; the force components occur sooner on the dry than slippery surface.

  5. Then & Now:Fifty years after Zamosky’s article "Shoe modifications in lower-extremity orthotics"

    OpenAIRE

    Jaap J. Van Netten, PhD; Klass Postema, MD, PhD

    2013-01-01

    The art and science of correcting foot deformities is still a mixture of tradition, artisan skill, clinical experience, and the prescribing doctor’s professional convictions” [1]. Zamosky’s 1964 article on various shoe modifications in lower-extremity orthotics starts with this observation [1]. Reflecting on 50 years of development in this field, we ask ourselves, Have the ingredients of this mixture changed?

  6. Detection of visually unrecognizable braking tracks using Laser-Induced Breakdown Spectroscopy, a feasibility study

    Science.gov (United States)

    Prochazka, David; Bilík, Martin; Prochazková, Petra; Brada, Michal; Klus, Jakub; Pořízka, Pavel; Novotný, Jan; Novotný, Karel; Ticová, Barbora; Bradáč, Albert; Semela, Marek; Kaiser, Jozef

    2016-04-01

    Identification of the position, length and mainly beginning of a braking track has proven to be essential for determination of causes of a road traffic accident. With the introduction of modern safety braking systems and assistance systems such as the Anti-lock Braking System (ABS) or Electronic Stability Control (ESC), the visual identification of braking tracks that has been used up until the present is proving to be rather complicated or even impossible. This paper focuses on identification of braking tracks using a spectrochemical analysis of the road surface. Laser-Induced Breakdown Spectroscopy (LIBS) was selected as a method suitable for fast in-situ element detection. In the course of detailed observations of braking tracks it was determined that they consist of small particles of tire treads that are caught in intrusions in the road surface. As regards detection of the "dust" resulting from wear and tear of tire treads in the environment, organic zinc was selected as the identification element in the past. The content of zinc in tire treads has been seen to differ with regard to various sources and tire types; however, the arithmetic mean and modus of these values are approximately 1% by weight. For in-situ measurements of actual braking tracks a mobile LIBS device equipped with a special module was used. Several measurements were performed for 3 different cars and tire types respectively which slowed down with full braking power. Moreover, the influence of different initial speed, vehicle mass and braking track length on detected signal is discussed here.

  7. Position control optimization of aerodynamic brake device for high-speed trains

    Science.gov (United States)

    Zuo, Jianyong; Luo, Zhuojun; Chen, Zhongkai

    2014-03-01

    The aerodynamic braking is a clean and non-adhesion braking, and can be used to provide extra braking force during high-speed emergency braking. The research of aerodynamic braking has attracted more and more attentions in recent years. However, most researchers in this field focus on aerodynamic effects and seldom on issues of position control of the aerodynamic braking board. The purpose of this paper is to explore position control optimization of the braking board in an aerodynamic braking prototype. The mathematical models of the hydraulic drive unit in the aerodynamic braking system are analyzed in detail, and the simulation models are established. Three control functions—constant, linear, and quadratic—are explored. Two kinds of criteria, including the position steady-state error and the acceleration of the piston rod, are used to evaluate system performance. Simulation results show that the position steady state-error is reduced from around 12-2 mm by applying a linear instead of a constant function, while the acceleration is reduced from 25.71-3.70 m/s2 with a quadratic control function. Use of the quadratic control function is shown to improve system performance. Experimental results obtained by measuring the position response of the piston rod on a test-bench also suggest a reduced position error and smooth movement of the piston rod. This implies that the acceleration is smaller when using the quadratic function, thus verifying the effectiveness of control schemes to improve to system performance. This paper proposes an effective and easily implemented control scheme that improves the position response of hydraulic cylinders during position control.

  8. Generation of Nanoparticles from Friction between Railway Brake Disks and Pads.

    Science.gov (United States)

    Namgung, Hyeong-Gyu; Kim, Jong-Bum; Woo, Sang-Hee; Park, Sechan; Kim, Minhae; Kim, Min-Soo; Bae, Gwi-Nam; Park, Duckshin; Kwon, Soon-Bark

    2016-04-01

    In this study, we measured the size distribution of particles ranging in size from 5.6 to 560 nm that were emitted between brake disks and pads under various braking conditions to observe and analyze changes to the resulting particle size distribution over braking time. A peak of 178-275 nm (200 nm peak) was observed in all braking conditions. However, the generation of spherical particles of a 10 nm range was observed only when the disk speed and brake force were above certain levels and intensified only when speed and brake force further increased. The total number concentration of ultrafine particles (no larger than 0.1 μm; PM0.1) generated was found to correlate with disk speed and brake force. Thus, the generation of nanoparticles resulting from disk speed and brake force was attributable primarily to increases in the contact surface temperature. The critical temperature for the generation of nanoparticles of a 10 nm range was found to be about 70 °C, which is the average temperature between the surface and the inside of the disk. If the speed or brake force was higher, that is, the temperature of the contact surface reached a certain level, evaporation and condensation took place. Vapor then left the friction surface, met with the air, and quickly cooled to form nanoparticles through nucleation. When the newly generated particles became highly concentrated, they grew through coagulation to form agglomerates or the vapor condensed directly onto the surface of existing particles of about 200 nm (formed by mechanical friction).

  9. The Effect of Shoe Outsole Containing Nanoclay Particles on Knee Joint Power during the Stance Phase of Running

    Directory of Open Access Journals (Sweden)

    Zahra Bassiri

    2014-10-01

    Full Text Available The popularity of running and consequently of running injuries has increased tends to develop shoe sole constructions aiming at preventing different injuries. The purpose of this study was to investigate the effect of shoe outsole containing nanoclay particles on knee joint power during stance phase of running. Fourteen healthy male shod runners run 3 times at 3.5 m.s-1 under three shoe conditions manufactured by polyurethane (PU, 1% Polyurethanes-clay nano-composites (NPU1 and 2% Polyurethanes-clay nano-composites (NPU2. The joint power (Pj was calculated by multiplying the joint moment (Mj and the joint angular velocity (ωj. Knee joint peak power in the three dimensional planes were compared between the shod conditions during the stance phase of running using repeated measurement ANOVA (P< 0.05. The results showed that the negative peak of knee joint power in sagittal plane was significantly different between the PU and NPU2 conditions. No significant differences were noted in other positive and negative peaks. It is concluded that using Polyurethanes-clay nano-composites can change shock absorbing ability of knee joint​.

  10. A Molecular Brake in the Kinase Hinge Region Regulates the Activity of Receptor Tyrosine Kinases

    Energy Technology Data Exchange (ETDEWEB)

    Chen,H.; Ma, J.; Li, W.; Eliseenkova, A.; Xu, C.; Neubert, T.; Miller, W.; Mohammadi, M.

    2007-01-01

    Activating mutations in the tyrosine kinase domain of receptor tyrosine kinases (RTKs) cause cancer and skeletal disorders. Comparison of the crystal structures of unphosphorylated and phosphorylated wild-type FGFR2 kinase domains with those of seven unphosphorylated pathogenic mutants reveals an autoinhibitory 'molecular brake' mediated by a triad of residues in the kinase hinge region of all FGFRs. Structural analysis shows that many other RTKs, including PDGFRs, VEGFRs, KIT, CSF1R, FLT3, TEK, and TIE, are also subject to regulation by this brake. Pathogenic mutations activate FGFRs and other RTKs by disengaging the brake either directly or indirectly.

  11. Design and Development of Hydraulic Disc Brake Systems for Well Servicing Rig Drawworks

    Institute of Scientific and Technical Information of China (English)

    Gao xiangqian; Zhou Yongxia

    1996-01-01

    @@ The conventional band brakes have been known to be important but also the most unlnerable part in servicing rig deawworks.. The failures in braking and releasing operations haven't well been avoided. There have evidently existed the problems of difficult operation and inconvenient maintenance in this connection. The use of power-assisted hydraulic cylinders or pneumatic cylinders can not meet the requirements of operations either. Since the late 1980s, we have cooperated with Shengli oilfields and others in the successful design and development of PST25 hydraulic disc brake systems for well servicing rig in a fully closed working state.

  12. RESEARCH ON DESIGN METHOD OF A MULTIPLE DISC WET BRAKE IN LUBRICATED ENVIRONMENT

    Institute of Scientific and Technical Information of China (English)

    Qin Datong; Sun Dongye

    2003-01-01

    The rmomechanical phenomena occurring between friction pairs greatly change the distributions of lining pressure and friction surface temperature of a multiple disc wet brake. It has become one of the main causes of brake failure. In order to understand these thermomechanical phenomena, several design and mate rial factors that have great influence on thermomechanical phenomena, such as heat transfer coefficient, friction factor, sliding velocity, initial lining pressure and so on, are analyzed. An isothermal design method is proposed for designing a multiple disc wet brake.

  13. 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.

  14. Braking indices of pulsars obtained in the presence of an effective force

    CERN Document Server

    Magalhaes, N S; Frajuca, C

    2016-01-01

    Braking indices of pulsars present a scientific challenge as their theoretical calculation is still an open problem. In this paper we report results of a study regarding such calculation which adapts the canonical model (which admits that pulsars are rotating magnetic dipoles) basically by introducing a compensating component in the energy conservation equation of the system. This component would correspond to an effective force that varies with the first power of the tangential velocity of the pulsar's crust. We test the proposed model using data available and predict braking indices values for different stars. We comment on the high braking index recently measured of the pulsar J1640-4631.

  15. A laboratory activity on the eddy current brake

    Science.gov (United States)

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

    2012-05-01

    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 electromagnetic properties of the magnet on the magnetic drag force. This video-based experiment is ideal for the study of kinematic graphs and the application of Newton's laws. Video motion analysis software enables students to make precise measurements of the magnet's position at incremental times during its motion, thus allowing them to quantify electromagnetic induction phenomena. The equipment needed for this experiment and data collection software are present in most physics teaching laboratories or are inexpensive and available.

  16. Atmospheric testing of wind turbine trailing edge aerodynamic brakes

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-31

    An experimental investigation was conducted using an instrumented horizontal-axis wind turbine that incorporated variable span trailing-edge aerodynamic brakes. A primary goal was to directly compare study results with (infinite-span) wind tunnel data and to provide information on how to account for device span effects during turbine design or analysis. Comprehensive measurements were utilized to define effective changes in the aerodynamic coefficients, as a function of angle of attack and control deflection, for three device spans and configurations. Differences in the lift and drag behavior are most pronounced near stall and for device spans of less than 15%. Drag performance is affected only minimally (<70%) for 15% or larger span devices. Interestingly, aerodynamic controls with characteristic vents or openings appear most affected by span reductions and three-dimensional flow.

  17. CONTRIBUTIONS TO THE DETERMINATION OF A MOULDING MATERIALS OTHER THAN STIFFENERS AND SHOES INSOLES

    Directory of Open Access Journals (Sweden)

    LUCA Cornelia

    2015-05-01

    Full Text Available The footwear insoles and heel counter stiffeners are made using fibrous structure materials. The spatial forming of these parts is made in moulds. After forming, the parts must have the same spatial dimensions with those of the shoe lasts used in the footwear manufacturing. During the forming process, the fibrous structure materials have an elastic-plastic behavior. So, for the moulds dimensioning, it is important to know the percentage of plastic deformation from the total deformation of the stressed material; this means to know the value of these materials forming subscript. The paper presents some theoretical and experimental contributions in finding of the forming subscript of the materials used in the footwear industry, for the footwear insoles and heel counter stiffeners manufacturing. Experiments were made on installations and experimental moulds sphere, cylinder and central angle. Experimental results shows that the forming subscript depends on the mould shape and the sample humidity when the stress is cancel. So, the deformations have a high rate, the sphere surfaces having the, highest forming subscript. In the case of sample forming which use cylinder moulds the value of the forming subscript on these surfaces is the lowest. In the case of the center angle occurs a a high level of plastic deformation. The results will be applied at the designing of the insoles and heel counter stiffeners moulds used for the pre-moulding.

  18. Water Level Gauging in a Tube by Using a Special Ultrasonic Shoe in an Immersion Tank

    International Nuclear Information System (INIS)

    An ultrasonic pulse travels through the thickness of a material, then finally it is reflected by the back or inside surface, and it can be returned to a transducer. In most applications this time interval is only a few microseconds or less. The measured two-way transit time is divided by two to account for the down-and-back travel path, and then multiplied by the velocity of the sound in a test material. The result is expressed by a well-known relationship as equation. In this experiment, a residual water level measurement in a bellow tube is obtained by using an immersion ultrasonic technique and a special UT probe attachment. This system was designed and fabricated for a convenient control in a water tank, which has a combination of a sensor and a position control function. The shoes are specially made with Lusite material which has the same shape as the bellows tube and then the immersion transducers are controlled by a 3-axis position control system, and it can be operated within a moving distance as small as 0.5mm. Certain specialized applications such as an underwater testing require a long cable between the transducer and the ultrasonic gauging target in an immersion tank

  19. A miniature shoe-mounted orientation determination system for accurate indoor heading and trajectory tracking

    Science.gov (United States)

    Zhang, Shengzhi; Yu, Shuai; Liu, Chaojun; Liu, Sheng

    2016-06-01

    Tracking the position of pedestrian is urgently demanded when the most commonly used GPS (Global Position System) is unavailable. Benefited from the small size, low-power consumption, and relatively high reliability, micro-electro-mechanical system sensors are well suited for GPS-denied indoor pedestrian heading estimation. In this paper, a real-time miniature orientation determination system (MODS) was developed for indoor heading and trajectory tracking based on a novel dual-linear Kalman filter. The proposed filter precludes the impact of geomagnetic distortions on pitch and roll that the heading is subjected to. A robust calibration approach was designed to improve the accuracy of sensors measurements based on a unified sensor model. Online tests were performed on the MODS with an improved turntable. The results demonstrate that the average RMSE (root-mean-square error) of heading estimation is less than 1°. Indoor heading experiments were carried out with the MODS mounted on the shoe of pedestrian. Besides, we integrated the existing MODS into an indoor pedestrian dead reckoning application as an example of its utility in realistic actions. A human attitude-based walking model was developed to calculate the walking distance. Test results indicate that mean percentage error of indoor trajectory tracking achieves 2% of the total walking distance. This paper provides a feasible alternative for accurate indoor heading and trajectory tracking.

  20. A miniature shoe-mounted orientation determination system for accurate indoor heading and trajectory tracking.

    Science.gov (United States)

    Zhang, Shengzhi; Yu, Shuai; Liu, Chaojun; Liu, Sheng

    2016-06-01

    Tracking the position of pedestrian is urgently demanded when the most commonly used GPS (Global Position System) is unavailable. Benefited from the small size, low-power consumption, and relatively high reliability, micro-electro-mechanical system sensors are well suited for GPS-denied indoor pedestrian heading estimation. In this paper, a real-time miniature orientation determination system (MODS) was developed for indoor heading and trajectory tracking based on a novel dual-linear Kalman filter. The proposed filter precludes the impact of geomagnetic distortions on pitch and roll that the heading is subjected to. A robust calibration approach was designed to improve the accuracy of sensors measurements based on a unified sensor model. Online tests were performed on the MODS with an improved turntable. The results demonstrate that the average RMSE (root-mean-square error) of heading estimation is less than 1°. Indoor heading experiments were carried out with the MODS mounted on the shoe of pedestrian. Besides, we integrated the existing MODS into an indoor pedestrian dead reckoning application as an example of its utility in realistic actions. A human attitude-based walking model was developed to calculate the walking distance. Test results indicate that mean percentage error of indoor trajectory tracking achieves 2% of the total walking distance. This paper provides a feasible alternative for accurate indoor heading and trajectory tracking. PMID:27370490

  1. Communicating Sustainable Shoes to Mainstream Consumers: The Impact of Advertisement Design on Buying Intention

    Directory of Open Access Journals (Sweden)

    Mirjam Visser

    2015-06-01

    Full Text Available Traditionally, marketing of sustainable products addresses green buyers, thus missing out on the mainstream consumers and volume necessary to cover the potentially higher cost of more sustainable materials. However, how to effectively communicate more sustainable products to mainstream consumers and to increase their buying intention is still underexplored. Combining personal and environmental benefits, called double benefit theory, is promoted as an effective green marketing strategy but so far not supported by quantitative research as being effective to reach mainstream consumers. We studied the effect of advertisement elements (layout color, benefit type, and heritage on the products’ perceived sustainability, quality and fashion image, and buying intentions of mainstream consumers. Two hundred adults participated in a study that was based on a 2 (red vs. green layout × 2 (personal vs. environmental benefit × 2 (local vs. global heritage between-subjects factorial design of a sustainable shoe advertisement. The impact of these independent variables on product image as well as on buying intention was analyzed by means of three-way ANOVAs. In line with the double benefit theory, combining a personal benefit with a green layout led to the highest buying intention. Moreover, a mediation analysis revealed the effect of emphasizing a personal benefit on buying intention was mediated by fashion image but not by sustainability. Sustainability, however, did have a positive effect on buying intentions independent of benefit type.

  2. The Comparative Analysis and Evaluation of Ecological Characteristics of Drum and Disk Wheel Brakes

    Directory of Open Access Journals (Sweden)

    Aleksandr Revin

    2011-04-01

    Full Text Available It is well-known that automobile transport as well as industry are the main sources of air pollution. In addition to exhaust gases, the flow of traffic releases a cloud of dust, consisting of over 60% of micro- and ultramicroscopic particles with radius of 10.0–0.25 µm, which are formed due to wheel abrasion (caused by the road grip of a tyre and the use of the brake blocks (in braking. The products formed in the process of wearing of the wheel brake pads are also the sources of the mass of fine dispersed particles over an urban highway. The authors analyse and evaluate ecological characteristics of drum and disk wheel brakes of vehicles.Article in Russian

  3. ANALYSIS OF POSSIBILITY TO AVOID A RUNNING-DOW ACCIDENT TIMELY BRAKING

    Directory of Open Access Journals (Sweden)

    Sarayev, A.

    2013-06-01

    Full Text Available Such circumstances under which the drive can stop the vehicle by applying timely braking before reaching the pedestrian crossing or decrease the speed to the safe limit to avoid a running-down accident is considered.

  4. Development and Analysis of Train Brake Curve Calculation Methods with Complex Simulation

    Directory of Open Access Journals (Sweden)

    Bela Vincze

    2006-01-01

    Full Text Available This paper describes an efficient method using simulation for developing and analyzing train brake curve calculation methods for the on-board computer of the ETCS system. An application example with actual measurements is also presented.

  5. Development of an Engine Air-Brake for Quiet Drag Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel quiet engine air-brake is proposed in response to NASA's solicitation for concepts for active and passive control of noise sources for conventional and...

  6. Mobile Acoustical Bat Monitoring Annual Summary Report CY 2012 to 2015 - Morgan Brake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These reports summarize bat calls collected along transects at Morgan Brake National Wildlife Refuge between 2012 and 2015. Calls were classified using Bat Call ID...

  7. Mobile Acoustical Bat Monitoring Annual Summary Report CY 2012 to 2015 - Mathews Brake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These reports summarize bat calls collected along transects at Mathews Brake National Wildlife Refuge between 2012 and 2015. Calls were classified using Bat Call ID...

  8. Development of an Engine Air-Brake for Quiet Drag Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel quiet engine air-brake (EAB) is proposed in response to NASA's solicitation for active and passive noise control concepts for conventional and advanced...

  9. Environmental Assessment of the Proposed Opening of Mathews Brake National Wildlife Refuge to Fishing

    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...

  10. Dynamic Analysis of a Floating Vertical Axis Wind Turbine Under Emergency Shutdown Using Hydrodynamic Brake

    DEFF Research Database (Denmark)

    Wang, K.; Hansen, Martin Otto Laver; Moan, T.

    2014-01-01

    axis wind turbine were carried out for emergency shutdown cases over a range of environmental conditions based on correlated wind and wave data. When generator failure happens, a brake should be applied to stop the acceleration of the rotor to prevent the rotor from overspeeding and subsequent disaster....... In addition to the traditional mechanical brake, a novel hydrodynamic brake was presented to apply to the shutdown case. The effects of the hydrodynamic brake on the platform motions and structural loads under normal operating conditions and during the emergency shutdown events were evaluated. The use of both......Emergency shutdown is always a challenge for an operating vertical axis wind turbine. A 5-MW vertical axis wind turbine with a Darrieus rotor mounted on a semi-submersible support structure was examined in this study. Coupled non-linear aero-hydro-servo-elastic simulations of the floating vertical...

  11. Mathews Brake National Wildlife Refuge Deer Harvest Records from 2011 Season

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These harvest data are from Mathews Brake during the 2011 deer season. They measure weight, antler size, prevalence of milk, and number of deer harvested.

  12. Morgan Brake National Wildlife Refuge Deer Harvest Records from 2011 Season

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These harvest data are from Morgan Brake during the 2011 deer season. They measure weight, antler size, prevalence of milk, and number of deer harvested.

  13. Upper Ouachita and Handy Brake National Wildlife Refuge: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan CCP was written to guide management on Upper Ouachita and Handy Brake NWRs for the next 15 years. This plan outlines the...

  14. Deer Harvest Records for Morgan Brake National Wildlife Refuge from 1995 to 2005

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These Deer Harvest Records show raw data for muzzleloader hunts collected from check in stations at Morgan Brake National Wildlife Refuge from 1995-2001 and 2005

  15. A method to model anticipatory postural control in driver braking events

    NARCIS (Netherlands)

    Osth, J.; Eliasson, E.; Happee, R.; Brolin, K.

    2014-01-01

    Human body models (HBMs) for vehicle occupant simulations have recently been extended with active muscles and postural control strategies. Feedback control has been used to model occupant responses to autonomous braking interventions. However, driver postural responses during driver initiated brakin

  16. Tribology of a Combined Yaw Bearing and Brake for Wind Turbines

    DEFF Research Database (Denmark)

    Poulios, Konstantinos

    that are affected by the tendency for building larger units, is the yaw system of horizontal axis wind turbines. State of the art wind turbine yaw systems consist of either a large roller element bearing or a corresponding segmented sliding bearing that connects the wind turbine nacelle and tower. An additional...... disc brake is typically included as an independent system. However, the increasing size of wind turbines makes roller element bearings an economically costly option. Moreover, the additional brake system increases complexity and consequently adds further production and maintenance costs. One...... of the innovations aiming at reducing complexity in the yaw system consists in combining a segmented sliding bearing and a brake into a single system. This thesis studies the tribological implications of such a hybrid sliding bearing and brake for the yaw system of wind turbines. Based to a large extent...

  17. STUDY ON THE CONTROL SYSTEM OF HYDRAULIC MOMENT-ADJUSTED BRAKE FOR DOWNWARD BELT CONVEYOR

    Institute of Scientific and Technical Information of China (English)

    孟国营; 徐志强; 霍森; 方佳雨

    1997-01-01

    Having analyzed the drawbacks on the design of control system of hydraulic momentadjusted brake system, the author presents a closed loop control system in the process of start and braking of the conveyer. On the basis of the concept of the critical time and the critical acceleration and its deductions, the working mode of the conveyer can be identified and controlled in feedback, furthermore, thus realize the process of soft start. In the deceleration process, the author points out the problems that exist in the present control system and sets forward the control process that acted by the combined function of brake moment of motor and the drag torque of hydraulic brake at the beginning of deceleration, it will further improved reliability of conveyor system.

  18. Application Research on Self-healing Technology with Microcapsules for Automobile Brake Pad

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; DONG Xiuping; ZHANG Heng

    2009-01-01

    In order to improve the performance of non-asbestos composite auto brake pads that are composed of matrix resin, reinforced material and fillers, a novel method with new technology of self-heal microcapsules was proposed. Nano reinforced fillers' effects were also considered in the experiment project. Five recipe designs for new composite auto brake pads were carried out and cor-responding samples were prepared as well. The friction coefficient and wearing properties at certain temperature, impact intensity and hardness were comparatively studied. Investigations indicate that properties of such composite auto brake pads meet the requirements of the national standards while microcapsule's weight content varies from 5.5wt%-1.09wt% of matrix resin and microcapsule's loca-tion varies in the pads. Nano reinforced fillers have the effects of increasing composites' impact in-tensity and hardness. Application of self-healing microcapsules in auto brake pads is feasible.

  19. An analysis of the friction mechanism on brake gear of railway rolling stock

    Directory of Open Access Journals (Sweden)

    J. H. Barnard

    1985-03-01

    Full Text Available Friction energy dissipation at an interface involves a wide range of interdisciplinary concepts. As the demand for higher operating speeds increased, the limitations of cast iron as the traditional friction material for rail transport brakes became more apparent. Only through an intensive analysis of the interfacial interaction between the brake block and brake path could the problems encountered with other promising friction materials be solved. The article deals with the difficulties pertaining to the early composite materials, and indicates how these were overcome by the understanding and implementation of new techniques not previously associated with conventional systems connected with railway braking. Two composite materials, that is 840/N for locomotives and freight wagons where mass oriented momentum dominates, and high friction composite 655/C for passenger vehicles with a predominantly speed-oriented momentum, are presently used.

  20. Theoretical and experimental study of an energy-reinforced braking radiation photon beam

    International Nuclear Information System (INIS)

    This research thesis reports the theoretical study of a photon beam raised towards high energies, its experimental implementation, the definition of a gamma spectrometry method which aimed at checking various hypotheses used in the beam theoretical study. After a presentation of the theory of phenomena of electron braking radiation, of materialisation of photons into positon-negaton pair, and of issues related to multiple Coulomb diffusion, the author reports the study of the different solutions which allow a photon beam to be obtained. A braking radiation of mono-kinetic electron has been used. This braking radiation is reinforced by absorption of low energy protons in a column of lithium hydride. The author describes how the beam is built up, and the experimental approach. He describes how raw data are processed to get rid of the influence of the multiple Coulomb diffusion and of the braking radiation. Experimental results are compared with those obtained by convolution of photon spectra and differential cross section