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Last update: November 12, 2013.
1

Fireproof Brake Hydraulic System.  

National Technical Information Service (NTIS)

The feasibility of a fireproof two-fluid brake hydraulic system which utilizes nonflammable chlorotrifluoroethylene (CTFE) fluid in a dead ended brake hydraulic system mechanically isolated from the primary MIL-H-5606 hydraulic system was studied. Experim...

S. M. Warren J. R. Kilner

1981-01-01

2

Combined hydraulic and regenerative braking system  

DOEpatents

A combined hydraulic and regenerative braking system and method for an electric vehicle, with the braking system being responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

Venkataperumal, Rama R. (Troy, MI); Mericle, Gerald E. (Mount Clemens, MI)

1981-06-02

3

Combined hydraulic and regenerative braking system  

DOEpatents

A combined hydraulic and regenerative braking system and method for an electric vehicle is disclosed. The braking system is responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

Venkataperumal, R.R.; Mericle, G.E.

1979-08-09

4

49 CFR 570.55 - Hydraulic brake system.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Hydraulic brake system. 570.55 Section...Than 10,000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles with hydraulic brake systems. (a) Brake...

2012-10-01

5

Development of Hydraulic Friction Brake for Railway Rolling Stock  

NASA Astrophysics Data System (ADS)

In this study, a novel hydraulic brake system is proposed in order to increase the reliability of railway brake systems. The reason hydraulic brake systems have not been taken up as a practical railway brake system until now is that the brake pressure control valve inherently has internal leakage and this causes insufficient fail-safe function. Accordingly, We focus on the development of a hydraulic brake pressure control valve (BPC valve) in this study. By virtue of adopting poppet elements in the valve, the braking force is maintained without internal leakage even when the electric power supply fails. The developed BPC valve includes a built-in pressure feedback mechanism and it enables the pressure control function to be maintained when the pressure transducer is broken. The operating principle and wear compensation methods for poppet elements are also examined in this study. The experimental results verify the linearity of static behavior, the stability, and the performance of the valve in maintaining output pressure.

Chenvisuwat, Thum; Park, Sung-Hwan; Kitagawa, Ato

6

Modeling and robust control design for aircraft brake hydraulics  

Microsoft Academic Search

This article describes the modeling of an electrohydraulic pressure servo valve and brake hydraulic system, and the design of an inner-loop controller which can be used with independent anti-skid or auto-brake controllers. The effects of the connecting lines on stability and performance are explicitly taken into account in the control design by using the analytical solutions to 2D viscous compressible

I. Tunay; E. Y. Rodin; A. A. Beck

2001-01-01

7

Combined Braking System for Electric Vehicles: Hydraulic/regenerative braking system permits energy recovery for electric vehicles without compromising the braking performance.  

National Technical Information Service (NTIS)

This citation summarizes a one-page announcement of technology available for utilization. A braking system for electric vehicles combines the advantages of hydraulic and regenerative systems into one. The arrangement retains the conventional action of hyd...

1983-01-01

8

49 CFR 570.55 - Hydraulic brake system.  

Code of Federal Regulations, 2011 CFR

...Brake tubes shall not be flattened or restricted. Brake hoses and tubes shall be attached or supported to prevent damage by vibration or abrasion. Master cylinder shall not show signs of leakage. Hose or tube protective rings or devices shall not be...

2011-10-01

9

The Application of Boolean Algebra in Modelling of Leakage Condition of a Car Hydraulic Braking System  

NASA Astrophysics Data System (ADS)

A general characteristics of a car hydraulic braking system (CHBS) is presented in this publication. A graphical model of properties-component objects is developed for the above-mentioned system. Moreover, four mathematical models in terms of logic, the set theory and the Boolean algebra of Boolean functions are developed. The examination is ended with a general model of the CHBS for n - Boolean variables and the construction and mathematical-technical interpretation of this model is presented.

Idzikowski, A.; Salamon, S.

2013-06-01

10

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

Code of Federal Regulations, 2010 CFR

...intact and functional. Friction facing tearout (complete...Any visible brake fluid or lubricant on the friction surface of the brake...facing. (b) The friction surface of the brake...for leakage of brake fluid or...

2010-10-01

11

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

Code of Federal Regulations, 2010 CFR

...intact and functional. Friction facing tearout (complete...Any visible brake fluid or lubricant on the friction surface of the brake...facing. (b) The friction surface of the brake...for leakage of brake fluid or...

2009-10-01

12

Automotive Brake Systems.  

ERIC Educational Resources Information Center

|This correspondence course, orginally developed for the Marine Corps, is designed to provide mechanics with an understanding of the basic operations of automotive brake systems on military vehicles. The course contains four study units covering hydraulic brakes, air brakes, power brakes, and auxiliary brake systems. A troubleshooting guide for…

Marine Corps Inst., Washington, DC.

13

49 CFR 393.53 - Automatic brake adjusters and brake adjustment indicators.  

Code of Federal Regulations, 2011 CFR

...adjustment indicators. (a) Automatic brake adjusters (hydraulic brake systems). Each commercial motor vehicle manufactured on or after October 20, 1993, and equipped with a hydraulic brake system, shall meet the automatic brake...

2011-10-01

14

49 CFR 393.53 - Automatic brake adjusters and brake adjustment indicators.  

Code of Federal Regulations, 2012 CFR

...adjustment indicators. (a) Automatic brake adjusters (hydraulic brake systems). Each commercial motor vehicle manufactured on or after October 20, 1993, and equipped with a hydraulic brake system, shall meet the automatic brake...

2012-10-01

15

Water Equilibration Studies, Brake Fluids.  

National Technical Information Service (NTIS)

The water absorption characteristics of various types of hydraulic brake fluids were studied at controlled humidities. Three series of tests were conducted using a wide scope of brake fluid types exposed to relative humidities ranging from 20% to 80%. Rat...

E. A. Mains

1967-01-01

16

14 CFR 25.735 - Brakes and braking systems.  

Code of Federal Regulations, 2013 CFR

...any electrical, pneumatic, hydraulic, or mechanical connecting...or if any single source of hydraulic or other brake operating...Fluid lost from a brake hydraulic system following a failure...is insufficient to cause or support a hazardous fire on the...

2013-01-01

17

Accumulator control for hydraulic actuating pressure of automatic transmission friction clutch or brake  

Microsoft Academic Search

This patent describes an accumulator system of an automatic transmission for controlling the time rate of pressure change in an hydraulically actuated friction element. It comprises: a source of line fluid pressure; control means for producing a first control pressure having a magnitude that varies according to a required torque transmitting capacity of the friction element; line modulator valve means

J. S. VanSelous; R. B. Abar

1989-01-01

18

Diagnosing a Dynamic System with (almost) no Observations A case study in off-board diagnosis of the hydraulic circuit of an anti-lock braking system  

Microsoft Academic Search

We present requirements and results of a case study in model-based (off-board-)diagnosis of the hydraulic circuit of an anti-lock braking system. The primary problems to be addressed quite fun- damental: it is impossible to predict the behavior of the system and, additionally, there are no meas- urements of the actual behavior available. Both might be considered fatal for model-based diagno-

Peter Struss; Martin Sachenbacher; Florian Dummert; Robert Bosch

1997-01-01

19

Brakes Specialist. Teacher Edition. Automotive Service Series.  

ERIC Educational Resources Information Center

|This document contains teacher's materials for a course on becoming an automotive brakes specialist, based on the National Institute of Automotive Service Excellence task lists. The course consists of three instructional units: service brake hydraulic system and wheel bearings, service drum brakes, and service disc brakes. Depending on the…

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

20

Fuzzy PID control on combined braking system of tracked vehicle with braking energy recovery system  

Microsoft Academic Search

To realize hydraulic hybrid tracked vehicle brake smoothly, mechanical and regenerative braking systems were present, and both working processes were analyzed. The models of both braking system were founded in AMESim. By using fuzzy PID controller, the braking process of tracked vehicle was co-simulated in MATLAB and AMESim. The output shows that the baking process is smooth, and fuzzy PID

Zhao Guang-jun; Lv Jian-gang

2010-01-01

21

Simulation of hydraulic anti-lock braking system control based on a co-simulation model by AMESim and Simulink  

Microsoft Academic Search

Established a simulation model of automotive of 15 DOF with the software of AMESim and Simulink\\/Stateflow and designed the ABS control method with four independent channel. The simulation was carried on under the low tire-road friction coefficient. The simulation results show that, the co-simulation model and its control method is able to simulate the actual ABS braking process, ensure the

Hui Lin; Chuanxue Song

2011-01-01

22

THE DRILLING DRAW-WORKS BAND BRAKES THERMAL REGIME  

Microsoft Academic Search

Operation systems of the drilling rigs are equipped with drilling draw-workses, which are provided both with mechanical and hydraulic brakes that can run separately or simultaneously. The mechanical brakes are band brake type, and they have the mission to take the biggest part of the braking moment, which appear during the rig operation. Because of the very high loads (up

Niculae Napoleon Antonescu

23

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

ERIC Educational Resources Information Center

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

Hilley, Robert; Scarberry, Terry; Kellum, Mary

24

Hydraulics.  

ERIC Educational Resources Information Center

|This curriculum guide contains a course in hydraulics to train entry-level workers for automotive mechanics and other fields that utilize hydraulics. The module contains 14 instructional units that cover the following topics: (1) introduction to hydraulics; (2) fundamentals of hydraulics; (3) reservoirs; (4) lines, fittings, and couplers; (5)…

Decker, Robert L.; Kirby, Klane

25

Hydraulics.  

ERIC Educational Resources Information Center

|These instructional materials provide an orientation to hydraulics for use at the postsecondary level. The first of 12 sections presents an introduction to hydraulics, including discussion of principles of liquids, definitions, liquid flow, the two types of hydraulic fluids, pressure gauges, and strainers and filters. The second section…

Engelbrecht, Nancy; And Others

26

The braking performance of a vehicle anti-lock brake system featuring an electro-rheological valve pressure modulator  

Microsoft Academic Search

This paper presents the braking performances of a vehicle anti-lock brake system (ABS) featuring an electro-rheological (ER) valve pressure modulator. As a first step, the principal design parameters of the ER valve and hydraulic booster are appropriately determined by considering the Bingham property of the ER fluid and the braking pressure variation during the ABS operation. An ER fluid composed

Seung-Bok Choi; Kum-Gil Sung; Myung-Soo Cho; Yang-Sub Lee

2007-01-01

27

Hydraulics.  

ERIC Educational Resources Information Center

|Designed for use in courses where students are expected to become proficient in the area of hydraulics, including diesel engine mechanic programs, this curriculum guide is comprised of fourteen units of instruction. Unit titles include (1) Introduction, (2) Fundamentals of Hydraulics, (3) Reservoirs, (4) Lines, Fittings, and Couplers, (5) Seals,…

Decker, Robert L.

28

Performance evaluation of a hybrid electric brake system with a sliding mode controller  

Microsoft Academic Search

A new conceptual hybrid electric brake system (HEBS) that combines a contact conventional hydraulic brake system (CBS) and a contactless Eddy current brake (ECB) system is proposed in this paper. An ECB generates brake force from the interaction between an Eddy current and a magnetic flux. However, an ECB cannot generate sufficient torque at low vehicle speeds. Also, the system

Jeonghoon Song

2005-01-01

29

Skin temperature and motorcyclists' braking performance.  

PubMed

16 male and 12 female students who had previous experience with hand-operated lever-braking systems performed braking tests with their hands at normal temperatures (mean hand temperatures 27.8 degrees C) and with their hands cooled to give finger temperatures of 6 degrees C and back of hand temperatures of 14 degrees C. Tasks required subjects, in response to a visual stimulus of a red light, to extend their digits to grip a motorcycle brake and pull it on. Reduced times were measured for (a) responding to the stimulus by grabbing the brake lever and pulling it to full braking pressure in the hydraulic system, (b) extending the digits, and (c) flexing the digits and pulling on the brake. In each case conditions produced a significant decrement in performance. This effect may occur when riding a motorcycle with cold hands, a common occurrence in Northern Europe. PMID:7110872

Parry, M

1982-06-01

30

BRAKE DEVICE  

DOEpatents

A brake device is described for utilization in connection with a control rod. The device comprises a pair of parallelogram link mechanisms, a control rod moveable rectilinearly therebetween in opposite directions, and shoes resiliently supported by the mechanism for frictional engagement with the control rod.

O' Donnell, T.J.

1959-03-10

31

Hydraulics  

NSDL National Science Digital Library

These interactive learning objects, created by instructors from Fox Valley Technical College and other colleges in the Wisconsin Technical College program, focus on concepts that cover a broad-based electromechanical program. Here visitors will find learning objects in Hydraulics with over 25 lessons in Actuators, Relief Valves, Basic Concepts, and Directional Control Valves.

2011-01-03

32

Electronic Motor Braking  

Microsoft Academic Search

Electronic motor brakes (EMB's) can be applied to both new and existing machines to provide a rapid nonmechanical adjustable braking profile. They can also be used to supplement the braking torque of existing brake motors, forming a complete sequential braking system for demanding applications. The EMB stops without friction or wear. It also provides for an adjustable soft stop and

Richard Shemanske

1983-01-01

33

Contact analysis for drum brakes and disk brakes using ADINA  

Microsoft Academic Search

Brakes in cars and trucks are safety parts. Requirements not only in performance but also in comfort, serviceability and working lifetime are high and rising. Optimal design of today’s brake systems is found using additional calculations based on finite element methods. For both types of brake systems, drum brakes and disk brakes, the different parts of brakes, i.e. the brake

C Hohmann; K Schiffner; K Oerter; H Reese

1999-01-01

34

Analysis of the regenerative brake system parameters for concrete mixing truck basded on AMESim  

Microsoft Academic Search

This article describes the concrete truck's hydraulic regenerative braking system structure, working mechanism, matching principle, and the relevant dynamic model. In order to achieve the purpose of simulating regenerative braking system, the software AMESim was used to establish physical model. By the target vehicle torque control strategy, according to the real parameters of the tuck, hydraulic parameters of secondary element

Cui Zhang; Xinhui Liu; Zhan Wang; Qiang Shi

2011-01-01

35

Muzzle Brake Analysis.  

National Technical Information Service (NTIS)

A relatively simple mathematical model, and computer program, has been developed for the purposes of estimating the instantaneous pressure distribution, momentum transfer, and braking force, experienced at the surface of a muzzle brake element exposed to ...

M. T. Soifer

1974-01-01

36

Automotive disc brake squeal  

Microsoft Academic Search

Disc brake squeal remains an elusive problem in the automotive industry. Since the early 20th century, many investigators have examined the problem with experimental, analytical, and computational techniques, but there is as yet no method to completely suppress disc brake squeal. This paper provides a comprehensive review and bibliography of works on disc brake squeal. In an effort to make

N. M. Kinkaid; O. M. O'Reilly; P. Papadopoulos

2003-01-01

37

Automatically resetting safety brake  

US Patent & Trademark Office Database

Antifrictional screws are used to permit the resetting of safety brakes of the type used in hoists. As in prior brakes, centrifugally operated dogs connect braking members, but in the present brakes the dogs also engage actuating members of the antifrictional screws, the screws being rotatable independently of their respective braking members. The dogs can be disengaged from the actuating members by merely operating the usual controls to raise cages of the hoists. The antifrictional screws in one embodiment are then free to be turned automatically independent of the rate of rotation of a braking member by force of usual spring washers disposed between the screws and respective braking members until the brakes are normally released. In modified types, dogs or pawls for controlling the amount of braking continue to engage respective actuating members for controlling rate of rotation of the screws until the cages have been raised sufficiently to release the brakes. For testing purposes, the dogs have easily operated rods associated with them for pushing outwardly the dogs at speeds below the usual speeds required for operation. In heavy-duty hoists, second dogs positioned to clear the actuating members are included to provide a moderate amount of braking in an ascending direction.

1981-03-31

38

Automotive Drum Brakes  

NSDL National Science Digital Library

Do you know when the first car was built? Do you know who built the first automobile? Would you guess, Henry Ford? Try again. Do you know by what means they used to stop that car? We know the brakes on the vehicles we drive today are quite different from those back in the 1800s. While knowing the history of the automobile is interesting, knowing how they work is also interesting. The automotive brake or to be more specific, the drum brake is what this instruction is designed to review. In this instruction, we will begin by briefly looking at the history of automobile brakes and then learn how drum brakes work. While disk brakes can be easier to understand, are becoming more and more popular, especially on the rear tires, drum brakes, to some can be a challenge. The purpose of this lesson is to provide you with resources and encourage you to search more additional resources that will help you gain a mental moving picture of how the drum brake works. OBJECTIVES: In this instructional module, you will: Know a brief history of automobile brakes. Have a minimum of 8 web resources that provide instructions of drum brakes. Develop a mental moving picture of how drum brakes work. MATERIALS: To complete this learning activity, each student will need: Access to a computer with internet connection capabilities. A strong desire ...

Hjorten, Mr.

2006-02-03

39

Brake Fundamentals. Automotive Articulation Project.  

ERIC Educational Resources Information Center

|Designed for secondary and postsecondary auto mechanics programs, this curriculum guide contains learning exercises in seven areas: (1) brake fundamentals; (2) brake lines, fluid, and hoses; (3) drum brakes; (4) disc brake system and service; (5) master cylinder, power boost, and control valves; (6) parking brakes; and (7) trouble shooting. Each…

Cunningham, Larry; And Others

40

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

NASA Astrophysics Data System (ADS)

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

Nguyen, Q. H.; Choi, S. B.

2010-11-01

41

Brake comfort – a review  

Microsoft Academic Search

Several state of the art papers and even books on brake vibration and\\/or noise have been presented in the literature. Many of them have analytically and sharply accounted for the impressive amount of research undertaken on this topic. This state of the art review focuses on the still-open questions that appear crucial from the perspective of a leading brake manufacturer.

Carlo Cantoni; Riccardo Cesarini; Giampiero Mastinu; Gianpiero Rocca; Roberto Sicigliano

2009-01-01

42

Cable Brake and Lock.  

National Technical Information Service (NTIS)

A cable brake and lock device to control the release of a mooring cable comprises a spring-biased piston abutting an elastic brake element, with the cable passing through both. An initial, preselected force is applied by the spring to the piston and the b...

H. P. Feldman

1976-01-01

43

Evaluation of Aircraft Brake Materials  

Microsoft Academic Search

A test program was carried out to evaluate several new high-temperature friction materials for use in aircraft disk brakes. A specially built test apparatus utilizing a disk brake and wheel half from a small jet aircraft was used. The apparatus enabled control of brake pressure, velocity and braking time. Tests were run under both constant and variables velocity conditions and

T. L. Ho; F. E. Kennedy; M. B. Peterson

1979-01-01

44

Vehicle brake testing system  

DOEpatents

This invention relates to a force measuring system capable of measuring forces associated with vehicle braking and of evaluating braking performance. The disclosure concerns an invention which comprises a first row of linearly aligned plates, a force bearing surface extending beneath and beside the plates, vertically oriented links and horizontally oriented links connecting each plate to a force bearing surface, a force measuring device in each link, a transducer coupled to each force measuring device, and a computing device coupled to receive an output signal from the transducer indicative of measured force in each force measuring device. The present invention may be used for testing vehicle brake systems.

Stevens, Samuel S [Harriman, TN; Hodgson, Jeffrey W [Lenoir City, TN

2002-11-19

45

Thermal seizures in automotive drum brakes  

Microsoft Academic Search

In automotive industry, drum brake system is used on two types of wheels: cast and spoke. Brake drum, brake panel and brake drum liner are important components of the brake system. Failures of these components observed during high-g braking on spoke wheels of a motorcycle are reported and systematically analyzed in this paper. The brake drum and the panel were

O. P. Singh; S. Mohan; K. Venkata Mangaraju; M. Jayamathy; R. Babu

2010-01-01

46

Aircraft hydraulic systems. Third edition  

SciTech Connect

The first nine chapters concern hydraulic components including: tubing, hoses, fittings, seals, pumps, valves, cylinders, and motors. General hydraulic system considerations are included in chapters five and nine, while pneumatic systems are covered in chapter ten. Chapters eleven through fifteen are devoted to aircraft-specific systems such as: landing gear, flight controls, brakes, etc. The material is rounded out with excerpts from the Canadair Challenger 601 training guide to illustrate the use of hydraulic systems in a specific aircraft application.

Neese, W.A.

1991-12-31

47

Pneumatic train brake simulation method  

Microsoft Academic Search

The design of new pneumatic brakes for rail vehicles or improvements of existing ones can be made better or more efficient by the use of a simulation method. This paper gives a general presentation of the author’s modelling methods used for solving problems relating to railway pneumatic brakes. The brake models in this paper (slightly different from those of other

Tadeusz Piechowiak

2009-01-01

48

Development of Aircraft Brake Materials.  

National Technical Information Service (NTIS)

The requirements of brake materials were outlined and a survey made to select materials to meet the needs of high temperature brakes. A number of metals and ceramic materials were selected and evaluated in sliding tests which simulated aircraft braking. N...

T. L. Ho M. B. Peterson

1974-01-01

49

Optimal Braking Studies.  

National Technical Information Service (NTIS)

To brake in minimum distance, the tire slip must be controlled to ride the peak of the mu-slip curve so that maximum ground force is developed between tire and pavement. The resulting control system differs from antiskid systems which react to impending w...

J. S. Pazdera

1972-01-01

50

Riser braking clamp apparatus  

SciTech Connect

A riser breaking clamp apparatus is described for use in a floating vessel having a substantially centrally positioned vertical hull opening therethrough. The vessel is provided with well drilling equipment, including an elongated vertical riser. The riser extends in tension down through the hull opening to a point adjacent the ocean floor, and motion-compensating and tensioning means are carried by the vessel operatively connected to the riser for tensioning the riser during normal operations. The invention comprises: riser braking clamp apparatus located substantially within the hull opening through the vessel, the riser braking clamp apparatus comprising: telescopic joint means having a first member and a second member, each member having a lower end and an upper end and axial throughbore, the lower end of the first member operatively connected to the upper end of the riser. The upper end of the first member is slideably engaged with the lower end of the second member, the second member operatively connected to the vessel; and brake means carried by one member of the telescopic joint means, operatively and selectively engageable with the other member of the telescopic joint means, to dampen, arrest, and prevent further movement of the first member relative to the second member of the telescopic joint means.

Langer, C.G.

1986-10-14

51

Effect of braking pressure and braking speed on the tribological properties of C\\/SiC aircraft brake materials  

Microsoft Academic Search

Effects of braking pressure and braking speed on the tribological properties of C\\/SiC aircraft brake materials has been studied using a disk-on-disk type laboratory scale dynamometer. The braking temperature increased with increasing braking speed and was less affected by changes in braking pressure. The friction coefficient increased to the maximum value at 10m\\/s and then fell with the increase of

Shangwu Fan; Litong Zhang; Laifei Cheng; Guanglai Tian; Shangjie Yang

2010-01-01

52

Gasdynamics of Perforated Muzzle Brakes.  

National Technical Information Service (NTIS)

In a study of perforated muzzle brakes, Nagamatsu, Choi, Duffy, and Carofano calculated the three-dimensional steady flow of a perfect gas through one vent hole and used the results to predict overall brake performance. The importance of the gas covolume ...

G. C. Carofano

1988-01-01

53

Friction mechanism in industrial brakes  

Microsoft Academic Search

Mechanical brakes are acting not stochastically but surprisingly determined as the presented results measured on industrial brake systems will show. They help understanding these complex friction systems. An important mechanism is thereby the periodically change of the local friction intensity during the continuous friction process. Another essential influence on the friction properties are the metal particles that originate from the

D. Severin; S. Dörsch

2001-01-01

54

Friction of Polymeric Brake Materials.  

National Technical Information Service (NTIS)

P.T.F.E. (Teflon) in brake material formulations produces a positive slope of coefficient of friction versus speed, on a Chase dynamometer. This sliding speed dependence is different from temperature dependence of friction. Teflon added to the brake formu...

K. C. Ludema

1974-01-01

55

Automatic transmission brake assembly including an overrunning roller brake and a friction brake  

Microsoft Academic Search

This patent describes an overrunning roller brake assembly for a planetary gear unit in an automatic transmission for automobiles, the gear unit having a ring gear, a carrier and a sun gear, the carrier having planet pinions thereon engaging the sun and ring gears; a brake for anchoring a reaction member of the gear unit, at least one other member

V. Premiski; R. Hohnel; C. Premiski

1988-01-01

56

49 CFR 393.52 - Brake performance.  

Code of Federal Regulations, 2010 CFR

...brake system and with no other brake system applied, a motor vehicle...which movement of the emergency brake control begins, that is not...smooth, and free of loose material. (2) The vehicle must...during the test. (d) Vehicle brake performance table: Type...

2009-10-01

57

49 CFR 393.52 - Brake performance.  

Code of Federal Regulations, 2010 CFR

...brake system and with no other brake system applied, a motor vehicle...which movement of the emergency brake control begins, that is not...smooth, and free of loose material. (2) The vehicle must...during the test. (d) Vehicle brake performance table: Type...

2010-10-01

58

Regenerative braking device  

DOEpatents

Disclosed are several embodiments of a regenerative braking device for an automotive vehicle. The device includes a plurality of rubber rollers (24, 26) mounted for rotation between an input shaft (14) connectable to the vehicle drivetrain and an output shaft (16) which is drivingly connected to the input shaft by a variable ratio transmission (20). When the transmission ratio is such that the input shaft rotates faster than the output shaft, the rubber rollers are torsionally stressed to accumulate energy, thereby slowing the vehicle. When the transmission ratio is such that the output shaft rotates faster than the input shaft, the rubber rollers are torsionally relaxed to deliver accumulated energy, thereby accelerating or driving the vehicle.

Hoppie, Lyle O. (Birmingham, MI)

1982-01-12

59

14 CFR 25.735 - Brakes and braking systems.  

Code of Federal Regulations, 2010 CFR

...system, if installed. (f) Kinetic energy capacity â(1) Design landing...The design landing stop brake kinetic energy absorption requirement of each...absorbing not less than this level of kinetic energy throughout the defined wear...

2010-01-01

60

14 CFR 25.735 - Brakes and braking systems.  

Code of Federal Regulations, 2010 CFR

...system, if installed. (f) Kinetic energy capacity â(1) Design landing...The design landing stop brake kinetic energy absorption requirement of each...absorbing not less than this level of kinetic energy throughout the defined wear...

2009-01-01

61

Mountain Plains Learning Experience Guide: Automotive Repair. Course: Brake Systems.  

ERIC Educational Resources Information Center

|One of twelve individualized courses included in an automotive repair curriculum, this course covers theory, operation, and repair of drum brakes, disc brakes, and brake system components. The course is comprised of six units: (1) Fundamentals of Brake Systems, (2) Master Cylinder, (3) Drum Brakes, (4) Disc Brakes, (5) Power Brakes, and (6)…

Schramm, C.; Osland, Walt

62

Variable ratio regenerative braking device  

DOEpatents

Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

Hoppie, Lyle O. (Birmingham, MI)

1981-12-15

63

A Switched Control Strategy for Antilock Braking System With On\\/Off Valves  

Microsoft Academic Search

In this paper, a switched control strategy for an antilock braking system (ABS), which has conventional hydraulic actuators equipped with on\\/off valves, is presented. The investi- gated system contains the continuous dynamics of the vehicle and the inherent discontinuous characteristics of the on\\/off valves. Accordingly, a novel approach based on nonlinear state feedback and a switching strategy renders a controller

Houhua Jing; Zhiyuan Liu; Hong Chen

2011-01-01

64

76 FR 55859 - Federal Motor Vehicle Safety Standards No. 121; Air Brake Systems  

Federal Register 2010, 2011, 2012, 2013

...by the petitioner does not support the conclusion that safety...deactivated. Rather, the data supports the conclusion that removing...trucks and buses equipped with hydraulic brakes), the agency solicited...petitioner provide any, to support this claim. However, we...

2011-09-09

65

Control of Asbestos Exposure during Brake Drum Service.  

National Technical Information Service (NTIS)

Earlier studies of airborne asbestos exposure to mechanics during brake maintenance operations showed overexposure to asbestos fibers during brake servicing, especially brake assembly cleaning. Because an estimated 150,000 brake mechanics and garage worke...

J. W. Sheehy T. C. Cooper D. M. O'Brien J. D. McGlothlin P. A. Froehlich

1989-01-01

66

Dynamic analysis of disc brake and impact law of related parameters on braking torque  

Microsoft Academic Search

A modeling method of parameterized flexible virtual prototype of disc brake was provided by the united application of finite element modeling (FEM) and dynamics analysis method. A virtual prototype of disc brake was created, in which the rotor, backplates and brake pads are flexible parts. A typical dynamics analysis in condition of the fully loaded braking process at the initial

Zhaojun Yang; Changliang Liu; Jixin Wang; Xun Yang

2010-01-01

67

49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.  

Code of Federal Regulations, 2010 CFR

... 6 2010-10-01 2010-10-01 false Vacuum brake assist unit and vacuum brake system. 570.56 Section 570.56 ...GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system....

2010-10-01

68

49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.  

Code of Federal Regulations, 2010 CFR

... 6 2009-10-01 2009-10-01 false Vacuum brake assist unit and vacuum brake system. 570.56 Section 570.56 ...GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system....

2009-10-01

69

Consideration of Materials for Aircraft Brakes.  

National Technical Information Service (NTIS)

An exploratory investigation was conducted concerning materials and their properties for use in aircraft brakes. Primary consideration was given to the heat dissipation and the frictional behavior of materials. Used brake pads and rotors were analyzed as ...

M. B. Peterson T. Ho

1972-01-01

70

Minimal models for disk brake squeal  

NASA Astrophysics Data System (ADS)

Numerous publications on the modeling of disk brake squeal can be found in the literature. Recent publications describe the onset of disk brake squeal as an instability of the trivial solution resulting from the non-conservative friction forces even for a constant friction coefficient. Therefore, a minimal model of disk brake squeal must contain at least two degrees of freedom. A literature review of minimal models shows that there is still a lack of a minimal model describing the basic behavior of disk brake squeal which can easily be associated to an automotive disk brake. Therefore, a new minimal model of a disk brake is introduced here, showing an obvious relation to the technical system. In this model, the vibration of the disk is taken into account, as it plays a dominant role in brake squeal. The model is analyzed with respect to its stability behavior, and consequences in using it in the optimization of disk brake systems are discussed.

von Wagner, Utz; Hochlenert, Daniel; Hagedorn, Peter

2007-05-01

71

Modeling hydraulic regenerative hybrid vehicles using AMESim and Matlab\\/Simulink  

Microsoft Academic Search

This paper presents the overview of the simulation modeling of a hydraulic system with regenerative braking used to improve vehicle emissions and fuel economy. Two simulation software packages were used together to enhance the simulation capability for fuel economy results and development of vehicle and hybrid control strategy. AMESim, a hydraulic simulation software package modeled the complex hydraulic circuit and

Alfred Lynn; Edzko Smid; Moji Eshraghi; Niall Caldwell; Dan Woody

2005-01-01

72

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT IX, AUTOMATIC TRANSMISSIONS--HYDRAULIC SYSTEM (PART I).  

ERIC Educational Resources Information Center

|THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OIL FLOW WITHIN HYDRAULIC TRANSMISSIONS USED ON DIESEL POWERED VEHICLES. TOPICS ARE GENERAL DESCRIPTION, HYDRAULIC CIRCUITS, AND BRAKE HYDRAULIC CIRCUIT AND OPERATION. THE MODULE CONSISTS OF A SELF-INSTRUCTIONAL PROGRAMED TRAINING FILM "LEARNING ABOUT THE ALLISON…

Human Engineering Inst., Cleveland, OH.

73

Temperature and torque determination in brake drums  

Microsoft Academic Search

Simulation of temperature distribution in a brake drum and determination of drum brake torque has been carried out using finite\\u000a element methods. The simulated temperature distribution and the brake torque determined were compared with observations carried\\u000a out using an inertia dynamometer with a data-logging system. There is good agreement between the predicted temperature distribution\\u000a and the brake torque determined with

V T V S Ramachandra Rao; L S Rajaram; K N Seetharamu

1993-01-01

74

Review of automotive brake friction materials  

Microsoft Academic Search

The gradual phasing-out of asbestos in automotive brake friction materials in many parts of the world has sparked the onset of extensive research and development into safer alternatives. As a result, the brake friction industry has seen the birth of different brake pads and shoes in the past decade, each with their own unique composition, yet performing the very same

D Chan; G W Stachowiak

2004-01-01

75

Dynamic thermal behavior of a brake system  

Microsoft Academic Search

A mathematical model is presented to describe the thermal behavior of a brake system that consists of shoe and drum. The model is solved analytically using Green's function method for any type of the stopping braking action. In terms of the obtained solutions, the transient temperature distribution of the brake is described. The thermal behavior is investigated for three specified

Malak Naji; M. Al-Nimr

2001-01-01

76

To brake or not to brake? Is there a question?  

Microsoft Academic Search

The vehicle following problem in an automated highway is approached from the point of view of safety. In particular the situation where an intervehicle collision is unavoidable and the relative velocity at impact is what determines the safety of the situation, is considered. It is shown, using tools from optimal control, that braking as hard as possible is not the

John Lygeros; El IBI

1996-01-01

77

Modern Carbon Composite Brake Materials  

Microsoft Academic Search

Carbon-carbon composites used in friction systems are becoming increasingly popular in aircrafts owing to their combination of low weight and high performance. Their current acceptance as brake materials is somewhat restrained due to two factors: cost and performance variations. Many manufacturers are taking steps toward improving their cost efficiency by utilizing lower cost precursor fibers and processing methodologies. At the

Christopher Byrne

2004-01-01

78

Rail Brake System Using a Linear Induction Motor for Dynamic Braking  

NASA Astrophysics Data System (ADS)

One type of braking system for railway vehicles is the eddy current brake. Because this type of brake has the problem of rail heating, it has not been used for practical applications in Japan. Therefore, we proposed the use of a linear induction motor (LIM) for dynamic braking in eddy current brake systems. The LIM reduces rail heating and uses an inverter for self excitation. In this paper, we estimated the performance of an LIM from experimental results of a fundamental test machine and confirmed that the LIM generates an approximately constant braking force under constant current excitation. At relatively low frequencies, this braking force remains unaffected by frequency changes. The reduction ratio of rail heating is also approximately proportional to the frequency. We also confirmed that dynamic braking resulting in no electrical output can be used for drive control of the LIM. These characteristics are convenient for the realization of the LIM rail brake system.

Sakamoto, Yasuaki; Kashiwagi, Takayuki; Tanaka, Minoru; Hasegawa, Hitoshi; Sasakawa, Takashi; Fujii, Nobuo

79

Falling Magnets and Electromagnetic Braking  

NASA Astrophysics Data System (ADS)

The slow fall of a rare earth magnet through a copper pipe is a striking example of electromagnetic braking; this remarkable phenomenon has been the subject of a number of scientific paper s [1, 2]. In a pipe having radius R and wall thickness D, the terminal velocity of the falling magnet is proportional to (R?4)/D. It is interesting to ask what happens in the limit as D becomes very large. We report our experimental observations and theoretical predictions of the dependence of the terminal velocity on pipe radius R for large D. [1] Y. Levin, F.L. da Silveira, and F.B. Rizzato, ``Electromagnetic braking: A simple quantitative model''. American Journal of Physics, 74(9): p. 815-817 (2006). [2] J.A. Pelesko, M. Cesky, and S. Huertas, Lenz's law and dimensional analysis. American Journal of Physics, 3(1): p. 37-39. 2005.

Culbreath, Christopher; Palffy-Muhoray, Peter

2009-03-01

80

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

Code of Federal Regulations, 2010 CFR

...activating level that is not less than 50 psi. For vehicles manufactured to conform...activating level that is not less than 60 psi. (4) The governor cut-in pressure shall be not lower than 80 psi, and the cut-out pressure shall be...

2009-10-01

81

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

Code of Federal Regulations, 2010 CFR

...activating level that is not less than 50 psi. For vehicles manufactured to conform...activating level that is not less than 60 psi. (4) The governor cut-in pressure shall be not lower than 80 psi, and the cut-out pressure shall be...

2010-10-01

82

Analysis of a regenerative braking system for Hybrid Electric Vehicles using an ElectroMechanical Brake  

Microsoft Academic Search

The regenerative braking system of the Hybrid Electric Vehicle (HEV) is a key technology that can improve fuel efficiency\\u000a by 20?50%, depending on motor size. In the regenerative braking system, the electronically controlled brake subsystem that\\u000a directs the braking forces into four wheels independently is indispensable. This technology is currently found in the Electronic\\u000a Stability Program (ESP) and in Vehicle

J. K. Ahn; K. H. Jung; D. H. Kim; H. B. Jin; H. S. Kim; S. H. Hwang

2009-01-01

83

A parametric study of perforated muzzle brakes  

NASA Astrophysics Data System (ADS)

A firing test was conducted to study the parameters influencing the recoil efficiency and the blast characteristics of perforated muzzle brakes. Several scaled (20 mm) devices were tested as candidates for the 105 mm Armored Gun System (AGS). Recoil impulse, blast overpressures, muzzle velocity, sequential spark shadowgraphs, and photographs of the muzzle flash were obtained. A total of nine different perforated brakes were tested as well as a scaled M 198 double muzzle brake.

Dillon, Robert E., Jr.; Nagamatsu, H. T.

1993-07-01

84

Asbestos dust exposure during brake repair  

Microsoft Academic Search

About 10,000 tons of chrysotile per year are used in the Federal Republic of Germany for the production of friction materials. During brake repair an unknown number of approximately 300,000 mechanics in automobile service stations are exposed to asbestos dust. In a field study, asbestos fiber concentrations during brake repair were measured. Occupational histories and chest X-rays of brake service

K. J. Roedelsperger; H. Jahn; B. M. Brueckel; J. Manke; R. Paur; H. J. Woitowitz

1986-01-01

85

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

ERIC Educational Resources Information Center

|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…

Tavares, J. M.

2009-01-01

86

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

ERIC Educational Resources Information Center

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…

Tavares, J. M.

2009-01-01

87

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

Microsoft Academic Search

High bandwidth actuation systems that are capable of simultaneously producing relatively large forces and displacements are required for use in automobiles and other industrial applications. Conventional hydraulic actuation mechanisms used in automotive brakes and clutches are complex, inefficient and have poor control robustness. These lead to reduced fuel economy, controllability issues and other disadvantages. This paper involves the design, development,

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

2005-01-01

88

Model Predictive Control of a Two Stage Actuation System using Piezoelectric Actuators for Controllable Industrial and Automotive Brakes and Clutches  

Microsoft Academic Search

High bandwidth actuation systems that are capable of simultaneously producing relatively large forces and displacements are required for use in automobiles and other industrial applications. Conventional hydraulic actuation mechanisms used in automotive brakes and clutches are complex, inefficient and have poor control robustness. These lead to reduced fuel economy, controllability issues and other disadvantages. Recently, a two-stage hybrid actuation mechanism

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

2008-01-01

89

Test Comparison for 20mm Perforated Muzzle Brakes.  

National Technical Information Service (NTIS)

Tests were conducted at the Ballistic Research Laboratory for a 20mm perforated muzzle brake. Six muzzle brake designs were analyzed for their influence on muzzle velocity, blast overpressure, and brake efficiency. The designs were a combination of scaled...

D. S. Savick

1993-01-01

90

49 CFR 570.5 - Service brake system.  

Code of Federal Regulations, 2010 CFR

...are not embossed, the drums and discs shall be within...Friction materials. On each brake the thickness of the lining...bonded linings or pads. Brake linings and pads shall...not impair attachment. Drum brake linings shall be...

2010-10-01

91

49 CFR 570.5 - Service brake system.  

Code of Federal Regulations, 2010 CFR

...are not embossed, the drums and discs shall be within...Friction materials. On each brake the thickness of the lining...bonded linings or pads. Brake linings and pads shall...not impair attachment. Drum brake linings shall be...

2009-10-01

92

49 CFR 570.59 - Service brake system.  

Code of Federal Regulations, 2010 CFR

...vehicles equipped with brake inspection ports or... (b) Disc and drum condition. If the...that time. If the drums and discs are not...materials. On each brake, the thickness of...friction surface. Drum brake linings shall be...

2009-10-01

93

49 CFR 570.59 - Service brake system.  

Code of Federal Regulations, 2010 CFR

...vehicles equipped with brake inspection ports or... (b) Disc and drum condition. If the...that time. If the drums and discs are not...materials. On each brake, the thickness of...friction surface. Drum brake linings shall be...

2010-10-01

94

49 CFR 236.701 - Application, brake; full service.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Application, brake; full service. 236.701 Section 236.701 Transportation ...APPLIANCES Definitions § 236.701 Application, brake; full service. An application of the brakes resulting from a...

2012-10-01

95

49 CFR 236.701 - Application, brake; full service.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Application, brake; full service. 236.701 Section 236.701 Transportation ...APPLIANCES Definitions § 236.701 Application, brake; full service. An application of the brakes resulting from a...

2011-10-01

96

Modeling and Simulation of Automotive Four-Channel Hydraulic ABS Based on AMESim and Simulink\\/Stateflow  

Microsoft Academic Search

Four-wheel automobile co-simulation model with AMESim and Simulink\\/Stateflow was established. Vehicle model was established with AMESim. Also, using AMESim we established a four-channel hydraulic system including ABS hydraulic modulator. The ABS controller model was established with Simulink\\/Stateflow. Co-simulation model simulates the vehicle braking performance on low adhesion road. Simulation result shows that ABS controller can effectively improve the vehicle's braking

Ji Wang; Chuanxue Song; Liqiang Jin

2010-01-01

97

Magnetic braking in cool dwarfs  

NASA Astrophysics Data System (ADS)

The authors discuss the thermocentrifugal wind theory of Mestel (1968) and Mestel and Spruit (1986). The theory is consistent with the vrot ? t-1/2 law, if the coronal temperature increases with rotation velocity as recent observations suggest. The authors present a generalized form for the braking law using the empirical relation Ro = 0.94 t91/2 for the Rossby number, where t9 is the age in units of 109yr, and discuss the observed deviations from this relation. Theoretical models (involving angular-momentum loss) of contact binaries and cataclysmic variables are also compared with this prediction.

Vilhu, Osmi; Moss, David

1986-11-01

98

A-REI Braking Distance  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Suppose that a particular model of car has a braking distance that can be computed as follows: When the car is traveling at $v$ miles per hour, its bra...

99

Temperatures reached in a bimetallic brake drum  

Microsoft Academic Search

A solution is given to permit the determination of the temperature attained at the friction surface of a bimetallic brake drum during a single brake application. No assumptions are made concerning the manner in which heat is shared between the drum and lining. This solution is then compared with those obtained when all the heat generated is assumed to enter

T P Newcomb

1960-01-01

100

Failure analysis of railway brake blocks  

Microsoft Academic Search

Past efforts of the Nigerian Railway Corporation to produce shoe brake blocks locally have proved unsuccessful; the brake blocks produced are defective, and are highly susceptible to brittle (catastrophic) failure. The objective of this work was to undertake failure analysis of locally produced shoe blocks, and to design a metallurgical process to produce efficient ones. To this end, mechanical and

John Ade Ajayi; O. A. Adeleke

1997-01-01

101

NAC Aftermarket Brake Components Project (Secondary Items).  

National Technical Information Service (NTIS)

NAC Aftermarket Brake Components Project -- 'To Promote Full-and- Open Competition' -- Internal Tasker by NAC Director: Fix sole-source brake component issues on HMMWV-ECV based on contractor and Congressional complaints. Objectives established 4Q FY05: R...

L. Miller

2007-01-01

102

Drilling riser braking apparatus and method  

SciTech Connect

A method is described of arresting and preventing further movement of the elements forming the upper end of a riser relative to a floating vessel therethrough. The vessel is provided with well drilling equipment including a derrick with associated drill string lift equipment, an elongated vertical riser provided with a riser brake contact area carried outwardly near the riser upper end thereof, a wellhead connector carried at the lower end of the riser and secured to a wellhead assembly, and adjustable buoyance means formed with the submerged portion of the riser. The riser extends in tension during normal operations down through the hull opening to a point adjacent the wellhead assembly located adjacent the ocean floor. The vessel carrying motion-compensating and tensioning means is operatively connected to the riser upper elements for vertically supporting the riser during normal operations, and provided with riser braking means apparatus. The apparatus includes at least one pair of brake elements carried by braking beams operatively connected to the vessel. The method comprises: moving the brake elements toward the riser brake contact area; engaging the brake elements with the riser brake contact area in order to dampen, arrest, and prevent further movement of the riser upper elements relative to the floating vessel; and remotely disconnecting the wellhead connector at the lower end of the riser from the wellhead assembly.

Langner, C.G.

1986-10-21

103

Electromagnetic braking of the flow of a liquid metal with a free surface  

NASA Astrophysics Data System (ADS)

The electromagnetic braking of liquid metal flowing over a moving boundary is considered. The flow is two dimensional and the upper boundary is a free surface. The main interest of this flow originates from the application of horizontal belt strip casting. In this process, the liquid metal is fed onto a single endless horizontal belt that runs between two rollers. The bottom of the belt is cooled by water and the liquid is fed onto the belt through a slit. This results in a flow that can be modelled as a flat free jet impinging onto a horizontally moving boundary. The flow after the impingement region is analysed using the boundary layer equations. Here, the flow depends on the Reynolds number R, the Froude number F, the Hartman number M, and the ratio of the belt velocity to jet velocity, ?. For ?< F-2/3, we have a supercritical flow which terminates in a hydraulic jump. For ?> F-2/3, there is no hydraulic jump and the film thickness grows smoothly into the final state with constant thickness and uniform velocity. The braking length for the case without hydraulic jump is shown to be of order O( F2/3Ra/2) without magnetic field and of order O( M-2Ra/2) with magnetic field, where a is the jet width. Thus, the magnetic field decreases the braking distance considerably. This result is favourable for both the stability of the flow and for the solidification process in the horizontal belt strip casting process.

Löfgren, Hans B.; Ĺkerstedt, Hans O.

1998-07-01

104

Driver experience with antilock brake systems.  

PubMed

Antilock brakes provide the capability for shorter stopping distances and the ability to steer and maintain control during hard braking, especially on wet and slippery surfaces. Owners of late model cars equipped with antilock brakes were surveyed in North Carolina and Wisconsin regarding their experiences with antilocks. The survey results indicated that more than 50% of the drivers in North Carolina and 40% in Wisconsin incorrectly indicated how to brake a car in an emergency situations on wet and slippery pavements in a way that will effectively activate the antilock feature. More drivers in Wisconsin than in North Carolina reported that their cars' antilock feature had been used, but more than 33% of the Wisconsin drivers and 62% of North Carolina drivers said they had never used the antilock feature of their cars' brakes. PMID:7857495

Williams, A F; Wells, J K

1994-12-01

105

Electrodynamic braking in high?speed rail transport  

Microsoft Academic Search

The paper considers electrodynamic braking of trains, which is of particular importance for high?speed railway transport from theoretical and technical perspectives. Braking methods used for high?speed trains should ensure compatibility and redundancy of braking systems. They include a mechanical method (based on adding frictional disks to wheelsets), as well as magnetic braking, which is being currently implemented and based on

Lionginas Liudvinavi?ius; Leonas Povilas Lingaitis

2007-01-01

106

Reaction times to neon, LED, and fast incandescent brake lamps  

Microsoft Academic Search

Standard incandescent brake lamps have a relatively slow rise time. It takes approximately a quarter of a second for them to reach 90% of asymptotic light output, causing potential delays in responses by following drivers. The present study evaluated reaction times to brake signals from standard incandescent brake lamps and from three alternative brake lamps with substantially faster rise times:

MICHAEL SIVAK; MICHAEL J. FLANNAGAN; TAKASHI SATO; ERIC C. TRAUBE; MASAMI AOKI

1994-01-01

107

Brakes. Auto Mechanics Curriculum Guide. Module 6. Instructor's Guide.  

ERIC Educational Resources Information Center

|This module is the sixth of nine modules in the competency-based Missouri Auto Mechanics Curriculum Guide. Eight units cover: introduction to automotive brake systems; disc and drum brake system components and how they operate; properties of brake fluid and procedures for bleeding the brake system; diagnosing and determining needed repairs on…

Allain, Robert

108

Airborne asbestos exposure during light aircraft brake replacement  

Microsoft Academic Search

Asbestos containing materials are a component of many vehicle brake systems, including those found in some light aircraft. To characterize the asbestos exposure that results from the installation and maintenance of these components, an aircraft fitted with asbestos containing brake pads had brake changes performed while both area and personal air samples were taken. The brake changing process took place

Charles L. Blake; Giffe T. Johnson; Raymond D. Harbison

2009-01-01

109

A Diagnostic System for Air Brakes in Commercial Vehicles  

Microsoft Academic Search

The safe operation of vehicles on roads depends, among other things, on a properly functioning brake system. Air brake systems are widely used in commercial vehicles such as trucks, tractor-trailers, and buses. In these brake systems, compressed air is used as the energy transmitting medium to actuate the foundation brakes mounted on the axles. In this paper, a model-based diagnostic

Shankar C. Subramanian; Swaroop Darbha; K. R. Rajagopal

2006-01-01

110

Temperature field change analysis of brake drums based on ANSYS  

Microsoft Academic Search

In this paper, the ANSYS is used to establish a three- dimensional model of brake drums, and then simulate the process of the brake drums' temperature rising through the forcing of boundary loads and initial conditions. After that the author reveal temperature field distribution of the brake drum brake element model, then verify the accuracy of model by an experiment,

Jingyu Liu; Yuan Feng; Hui Liu; Tao Wang; Xuna Guo; Shuo Zhang

2011-01-01

111

Asbestos dust exposure during brake repair  

SciTech Connect

About 10,000 tons of chrysotile per year are used in the Federal Republic of Germany for the production of friction materials. During brake repair an unknown number of approximately 300,000 mechanics in automobile service stations are exposed to asbestos dust. In a field study, asbestos fiber concentrations during brake repair were measured. Occupational histories and chest X-rays of brake service mechanics are being examined. Ninety dust measurements in 76 service stations were made by phase contrast microscopy and by scanning transmission electron microscopy. By electron microscopy, extremely fine chrysotile fibers with lengths less than 5 microns were identified in brake drum dust. Fibers with lengths greater than or equal to 5 microns constituted less than 1% of all chrysotile fibers counted in brake drum dust. Short-term asbestos dust exposures were measured by light microscopy in 101 personal samples during blowing out of brakes, and grinding and turning of brake linings. During blowing out of car brakes, as well as during grinding of brake linings, the product of fiber concentration with length greater than 5 microns and sampling time amounted to about 4-5 fibers/ml X min corresponding to a concentration of 10(6) fibers/m3 over 4-5 min. For trucks and buses higher amounts of 5-10 X 10(6) fibers/m3 X min were observed during these operations. From occupational histories of 210 vehicle mechanics, an average duration of employment of mean +/- s = 21 +/- 10 years and a mean cumulative fiber dose of mean +/- s = (0.54 +/- 1.1) X 10(6) fibers/m3 X years were calculated.

Roedelsperger, K.J.; Jahn, H.; Brueckel, B.M.; Manke, J.; Paur, R.; Woitowitz, H.J.

1986-01-01

112

Asbestos dust exposure during brake repair.  

PubMed

About 10,000 tons of chrysotile per year are used in the Federal Republic of Germany for the production of friction materials. During brake repair an unknown number of approximately 300,000 mechanics in automobile service stations are exposed to asbestos dust. In a field study, asbestos fiber concentrations during brake repair were measured. Occupational histories and chest X-rays of brake service mechanics are being examined. Ninety dust measurements in 76 service stations were made by phase contrast microscopy and by scanning transmission electron microscopy. By electron microscopy, extremely fine chrysotile fibers with lengths less than 5 microns were identified in brake drum dust. Fibers with lengths greater than or equal to 5 microns constituted less than 1% of all chrysotile fibers counted in brake drum dust. Short-term asbestos dust exposures were measured by light microscopy in 101 personal samples during blowing out of brakes, and grinding and turning of brake linings. During blowing out of car brakes, as well as during grinding of brake linings, the product of fiber concentration with length greater than 5 microns and sampling time amounted to about 4-5 fibers/ml X min corresponding to a concentration of 10(6) fibers/m3 over 4-5 min. For trucks and buses higher amounts of 5-10 X 10(6) fibers/m3 X min were observed during these operations. From occupational histories of 210 vehicle mechanics, an average duration of employment of mean +/- s = 21 +/- 10 years and a mean cumulative fiber dose of mean +/- s = (0.54 +/- 1.1) X 10(6) fibers/m3 X years were calculated. PMID:3017102

Rödelsperger, K; Jahn, H; Brückel, B; Manke, J; Paur, R; Woitowitz, H J

1986-01-01

113

Thermal tribological behaviour of composite carbon metal\\/steel brake  

Microsoft Academic Search

Friction behaviour of carbon brake block\\/brake drum system is studied at high sliding speed (?=2000 tr\\/mn; v=13 m\\/s) under high applied normal load (P=20 Kg). The mean contact temperature is measured by K-thermocouple placed in brake block and in brake drum. The real contact temperature is calculated. Friction behaviour and temperature evolution will be given and discussed versus the brake

H. Zaidi; A Senouci

1999-01-01

114

Control of Asbestos Exposure during Brake Drum Service  

Microsoft Academic Search

An estimated 150,000 brake mechanics and garage workers in the U.S. are potentially exposed to asbestos, a known health hazard. Earlier studies of airborne asbestos exposures to mechanics during brake maintenance operations showed overexposure to asbestos fibers during brake servicing, especially brake assembly cleaning. Most brake service operations are performed by small businesses that lack resources to evaluate control devices.The

John W. Sheehy; Thomas C. Cooper; Dennis M. Obrien; J. D. McGlothlin; P. A. Froehlich

1989-01-01

115

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

NASA Astrophysics Data System (ADS)

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

Tavares, J. M.

2009-07-01

116

Experimental Study of Perforated Muzzle Brakes.  

National Technical Information Service (NTIS)

A firing test was conducted to examine the recoil efficiency and blast characteristics of perforated muzzle brakes fitted to a 20-mm cannon. Recoil impulse blast overpressures, muzzle velocity, sequential spark shadowgraphs, and photographs of the muzzle ...

R. E. Dillon H. T. Nagamatsu

1984-01-01

117

Brake Friction Materials: A Market Survey.  

National Technical Information Service (NTIS)

A composition material developed by National Aeronautics and Space Administration (NASA) may be useful as an improved vehicle brake friction material. To assist NASA in identifying a potential market for this material, the SRI Technology Applications Team...

A. V. Loomis J. P. Wilhelm

1975-01-01

118

14 CFR 23.735 - Brakes.  

Code of Federal Regulations, 2013 CFR

...must not be less than the kinetic energy absorption requirements determined under either...methods: (1) The brake kinetic energy absorption requirements must be based on a conservative...rational analysis, the kinetic energy absorption requirements for each main wheel...

2013-01-01

119

Stored Energy Management for Regenerative Braking Applications.  

National Technical Information Service (NTIS)

The use of regenerative braking devices to conserve energy during repeated speed changes of vehicles is well known. Practical systems based on electrical energy storage in batteries and kinetic energy storage in flywheels have been developed to the commer...

F. M. Russell

1983-01-01

120

Experimental Identification of Brake Pad Material Properties-A Step Towards a Better Prediction of Brake Squeal  

Microsoft Academic Search

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

Sylwia Hornig; Daniel Hochlenert; Utz von Wagner

2010-01-01

121

An experimental study of perforated muzzle brakes  

NASA Astrophysics Data System (ADS)

A firing test was conducted to examine the recoil efficiency and blast characteristics of perforated muzzle brakes fitted to a 20 mm cannon. Recoil impulse blast overpressures, muzzle velocity, sequential spark shadowgraphs, and photographs of the muzzle flash structure were obtained. Three different nuzzle devices were used with one device equipped with pressure transducers to measure the static pressure in the brake. Experimental results are compared with the earlier predictions of Dillon and Nagamatsu.

Dillon, R. E., Jr.; Nagamatsu, H. T.

1984-06-01

122

Brake for counter rotating bladed members  

SciTech Connect

This patent describes a propulsion system including a gas turbine engine having an output shaft and a gear drive having a planetary gear set with a first element connected to the engine output shaft and a second element connected to a first bladed member and a third element connected to a second bladed member whereby the first and second bladed members are rotated in opposite directions by the output shaft. A brake is described comprising, a first transfer shaft supported on a stationary housing for rotation about an axis of the latter, a second transfer shaft supported on the stationary housing for rotation about the axis, gear means between one of the counter rotating bladed members and the first transfer shaft and gear means between the other of the counter rotating bladed members and the second transfer shaft. The brake also includes a selectively operable brake actuator on the housing movable between an extended position and a retracted position, and friction means between the brake actuator and each of first and second transfer shafts operative in the extended position of the brake actuator to simultaneously frictionally retard rotation of each of the first and the second transfer shafts whereby each of the counter rotating bladed members is simultaneously braked.

Cedoz, R.W.

1987-02-10

123

Characterisation of Semi-Metallic Brake Pads using Brake Dynamometer  

NASA Astrophysics Data System (ADS)

Friction materials are complex mix of fibres, modifiers, additives, fillers and a binder resin which holds them together and are composed of between 5 and 20 elements in the composition. Each element has its own function and changing any element or its weight percentage will change the friction material properties. Besides, there is no rule of thumb whereupon the friction and wear performance can be predicted based on physical and mechanical properties. Therefore, each developed formulation needs to be subjected to dynamometer test for screening purpose prior to on-vehicle test to reduce development cost and. In this study, four formulations developed for passenger cars through powder metallurgy technique were subjected to dynamometer tests in accordance with Society of Automotive Engineers standard SAE 2552, dynamometer global brake effectiveness test. Test results show that sample S2 and S8 comply with the minimum requirement under all test segments and hence prototype sample could be prepared for further evaluation by performing on the road performance test.

Talib, R. J.; Othman, E.; Kasiran, R.

2010-03-01

124

Hydraulic Car  

NSDL National Science Digital Library

In this activity, learners build cars using syringes and water-powered hydraulics. Learners construct the car frame out of cardboard and set up a hydraulic system to raise and lower the car. Use this project to introduce learners to incompressible fluids and Pascal's Principle.

Workshop, Watsonville E.

2011-01-01

125

Performance of ceramic enhanced phenolic matrix brake lining materials for automotive brake linings  

Microsoft Academic Search

Despite the number of research studies completed on the mechanism of friction in automotive brake lining materials, the phenomenon is still not fully understood. Complex mechano-chemical processes occurring on the friction interface of a composite friction material make it difficult to understand the correlation between the formulation of brake lining and the frictional performance. This paper concentrates on (i) the

K. W. Hee; P. Filip

2005-01-01

126

Desperately Driven and No Brakes  

PubMed Central

ANDERSEN, S.L. and TEICHER, M.H. Desperately driven and no brakes: Developmental stress exposure and subsequent risk for substance abuse. NEUROSCI BIOBEHAV REV XX(X) XXX-XXX, 2008. Adverse life events are associated with a wide range of psychopathology, including an increased risk for substance abuse. In this review, we focus on the inter-relationship between exposure to adversity and brain development, and relate this to enhanced windows of vulnerability. This review encompasses clinical and preclinical data, drawing evidence from epidemiological studies, morphometric and functional imaging studies, and molecular biology and genetics. The interaction of exposure during a sensitive period and maturational events produces a cascade that leads to the initiation of substance use at younger ages, and increases the likelihood of addiction by adolescence or early adulthood. A stress-incubation/corticolimbic dysfunction model is proposed based on the interplay of stress exposure, development stage, and neuromaturational events that may explain the seeking of specific classes of drugs later in life. Three main factors contribute to this age-based progression of increased drug use: 1) a sensitized stress response system; 2) sensitive periods of vulnerability; and 3) maturational processes during adolescence. Together, these factors may explain why exposure to early adversity increases risk to abuse substances during adolescence.

Andersen, Susan L.; Teicher, Martin H.

2009-01-01

127

Magnetic braking in galactic flows  

SciTech Connect

The nuclear fireworks of active galaxies are believed to derive their power from the kinetic energy of gas falling onto a massive central objects; mass shed from evolving galactic stars is an obvious source of fuel for this process. But this ejected material shares the galactic rotation, and a centrifugal barrier will prevent it from reaching the nucleus, if its angular momentum is not removed. This paper shows that, if the large-scale galactic magnetic field has a strong enough radial component, magnetic torques can act to spin down the infalling matter. Rotation of the interstellar gas induces a toroidal magnetic field, and Maxwell stresses remove angular momentum from the flow; gas can then fall inward to the galactic center. In this way, the monster in the nucleus can be fed on gas from a galaxy's own stars. The magnetic fields in M87 and NGC 1275, giant elliptical galaxies which are accreting from an intracluster medium, appear to be strong enough to allow magnetic braking.

Sparke, L.S.

1982-09-01

128

Development and use of an apparatus for tribological evaluation of ceramic-based brake materials  

Microsoft Academic Search

Automotive braking systems normally employ brake discs made of steel or grey cast iron, which are then paired with composite organic brake pads. These types of materials are suitable for use in braking systems with moderate loads, but car manufacturers are tending to design increasing numbers of prestige and sports-class vehicles that need braking systems with more braking power. As

M. Kermca; M. Kalina; J. Vižintin

2005-01-01

129

14 CFR 23.493 - Braked roll conditions.  

Code of Federal Regulations, 2013 CFR

...CATEGORY AIRPLANES Structure Ground Loads § 23.493 Braked roll conditions. Under braked roll conditions, with the shock absorbers and tires in their static positions, the following apply: (a) The limit vertical load factor must be...

2013-01-01

130

14 CFR 27.493 - Braked roll conditions.  

Code of Federal Regulations, 2013 CFR

...ROTORCRAFT Strength Requirements Ground Loads § 27.493 Braked roll conditions. Under braked roll conditions with the shock absorbers in their static positionsâ (a) The limit vertical load must be based on a load factor of at leastâ...

2013-01-01

131

14 CFR 29.493 - Braked roll conditions.  

Code of Federal Regulations, 2013 CFR

...ROTORCRAFT Strength Requirements Ground Loads § 29.493 Braked roll conditions. Under braked roll conditions with the shock absorbers in their static positionsâ (a) The limit vertical load must be based on a load factor of at leastâ...

2013-01-01

132

Investigation of the Speed Brakes on the S-67 Aircraft.  

National Technical Information Service (NTIS)

Flight tests and computer simulations to evaluate speed brakes for a winged helicopter were conducted. The flight test program established the effectiveness of wing-mounted speed brakes for increasing dive angle, deceleration capability, and maneuverabili...

N. F. K. Kefford

1972-01-01

133

Thermal tribological behaviour of composite carbon metal/steel brake  

NASA Astrophysics Data System (ADS)

Friction behaviour of carbon brake block/brake drum system is studied at high sliding speed ( ?=2000 tr/mn; v=13 m/s) under high applied normal load ( P=20 Kg). The mean contact temperature is measured by K-thermocouple placed in brake block and in brake drum. The real contact temperature is calculated. Friction behaviour and temperature evolution will be given and discussed versus the brake block effusivity/drum brake effusivity ratio and versus Peclet number. Carbon brake block thermal and mechanical damage is observed under high dynamic load (high applied normal load and high sliding speed). The transferred films are analysed and quantified by Scanning Electron Microscopy. The aim of this paper is to present the tribological results versus normal load and sliding speed; and the contact temperature. We will present and discuss thermo-mechanical surface damage analysis of brake block.

Zaidi, H.; Senouci, A.

1999-04-01

134

1. OBLIQUE VIEW OF HOIST, SHOWING CABLE DRUM, WOODEN BRAKE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. OBLIQUE VIEW OF HOIST, SHOWING CABLE DRUM, WOODEN BRAKE SHOES AND BRAKE HANDLE, LOOKING NORTH - Buffalo Coal Mine, Vulcan Cable Hoist, Wishbone Hill, Southeast end, near Moose Creek, Sutton, Matanuska-Susitna Borough, AK

135

30 CFR 57.19017 - Emergency braking for electric hoists.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Emergency braking for electric hoists. 57.19017 Section 57.19017 Mineral... Hoists § 57.19017 Emergency braking for electric hoists. Each electric hoist shall be equipped with a...

2013-07-01

136

49 CFR 238.309 - Periodic brake equipment maintenance.  

Code of Federal Regulations, 2012 CFR

...STANDARDS Inspection, Testing, and Maintenance Requirements...equipment's brake system pneumatic components that contain...equipment and brake cylinders of each DMU or MU...cleaning, repairing, and testing required by this...cleaning, repairing, and testing and maintain an...

2012-10-01

137

49 CFR 232.109 - Dynamic brake requirements.  

Code of Federal Regulations, 2012 CFR

... (1) Conduct an electrical integrity test of...brake to determine if electrical current is being received at the grids on the system; and...brake to determine if electrical current is being received at the grids on the system;...

2012-10-01

138

49 CFR 232.109 - Dynamic brake requirements.  

Code of Federal Regulations, 2011 CFR

... (1) Conduct an electrical integrity test of...brake to determine if electrical current is being received at the grids on the system; and...brake to determine if electrical current is being received at the grids on the system;...

2011-10-01

139

16 CFR 1512.5 - Requirements for braking system.  

Code of Federal Regulations, 2013 CFR

...SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.5 Requirements...braking system. (a) Braking system. Bicycles shall be equipped with front- and rear-wheel...components. (1) Stopping distance. A bicycle equipped with only handbrakes...

2013-01-01

140

The dynamic braking of induction motors  

NASA Astrophysics Data System (ADS)

The dynamic braking of induction motors is investigated with particular emphasis on the use of zero-sequence connections. The braking performance using both ac and dc supplies is compared. A mathematical model is developed to predict both the transient and steady-state zero-sequence braking performance. To ensure accurate calculations, a model is constructed to allow for the variation of secondary parameters with frequency due to the skin effect. A method for determining the zero-sequence parameters using locked rotor variable frequency data is presented. To measure the transient acceleration torque of the machine, a rotational accelerometer is developed from a small single-phase induction motor. Good correlation between measured and calculated results is achieved during switching transients for both current and torque.

Hickman, B.

1985-03-01

141

Transient thermal behavior of a cylindrical brake system  

NASA Astrophysics Data System (ADS)

A mathematical model is presented to describe the thermal behavior of a brake system which consists of shoe and drum. The model is solved analytically using Green's function method for any type of the stopping braking action. In terms of the obtained solutions, the transient temperature distribution of the brake is described. The thermal behavior is investigated for three specified braking actions which are the impulse, unit step and trigonometric stopping actions.

Naji, M.; Al-Nimr, M.; Masoud, S.

142

Coordinated Control of Four Wheel Braking and Rear Steering  

Microsoft Academic Search

In this paper, we consider a coordinated control of four-wheel independent braking and rear steering. The objective of the control system is to improve the overall vehicle handling performance during combined braking and turning maneuvers. The braking and steering inputs of the driver are interpreted as vehicle deceleration and yaw rate commands, respectively. The control system is designed using the

Mutasim Salman; Zhihong Zhang; Nader Boustany

1992-01-01

143

49 CFR 232.305 - Single car air brake tests.  

Code of Federal Regulations, 2010 CFR

...Tests-Standard Freight Brake Equipment,â and Section 4.0...S-486-04, âCode of Air Brake System Tests for Freight Equipment...on the availability of this material at NARA, call 202-741-6030...shall perform a single car air brake test on a car when:...

2009-10-01

144

49 CFR 232.305 - Single car air brake tests.  

Code of Federal Regulations, 2010 CFR

...Tests-Standard Freight Brake Equipment,â and Section 4.0...S-486-04, âCode of Air Brake System Tests for Freight Equipment...on the availability of this material at NARA, call 202-741-6030...shall perform a single car air brake test on a car when:...

2010-10-01

145

Evaluation of Disc Brake Materials for Squeal Reduction  

Microsoft Academic Search

A nontraditional evaluation tool is introduced to examine the effects of different materials, in practical applications, which are used in fabricating disc brake components for commonly used or special requirements such as heavy duty performance and racing cars. As an extension to earlier FE disc brake models, a detailed FE model of the whole disc brake corner that incorporates wheel

J. Abdo; M. Nouby; D. Mathivanan; K. Srinivasan

2011-01-01

146

On the role of copper in brake friction materials  

Microsoft Academic Search

Copper is a major ingredient in friction materials used for automotive braking. The purpose of this study was to find out how copper contributes to good brake performance properties in addition to providing good thermal conductivity. Microstructural investigations of copper chips at the surfaces of brake pads revealed a zone of severe plastic deformation which provides high hardness, but there

W. Österle; C. Prietzel; H. Kloß; A. I. Dmitriev

2010-01-01

147

Regenerative braking control method and optimal scheme for electric motorcycle  

Microsoft Academic Search

This paper describes an optimal regenerative braking control scheme for a permanent magnet brushless DC motor of an electric motorcycle to achieve dual goals of the electric brake and the maximal power harvest in two cases of the road, downhill and flat, without any additional changes on the hardware. Based on regenerative braking of brushless DC motor in half bridge

Wei Cui; Hang Zhang; Yan-li Ma; Yue-jin Zhang

2011-01-01

148

49 CFR 570.6 - Brake power unit.  

Code of Federal Regulations, 2012 CFR

...570.6 Brake power unit. (a) Vacuum hoses shall not be collapsed, abraded...mounted, or audibly leaking. With residual vacuum exhausted and a constant 25 pound...service brakes several times to destroy vacuum in system. Depress brake pedal with...

2012-10-01

149

Linear eigenvalue analysis of the disc-brake squeal problem  

Microsoft Academic Search

SUMMARY This paper presents a numerical method to calculate the unstable frequencies of a car disc brake and suggests a suitable analysis procedure. The stationary components of the disc brake are modelled using finite elements and the disc as a thin plate. The separate treatments of the stationary components and the rotating disc facilitate the modelling of the disc brake

Q. Cao; H. Ouyang; M. I. Friswell; J. E. Mottershead

2004-01-01

150

49 CFR 232.305 - Single car air brake tests.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Single car air brake tests. 232.305 Section 232.305...and Testing Requirements § 232.305 Single car air brake tests. (a) Single car air brake tests shall be performed by a...

2012-10-01

151

49 CFR 232.305 - Single car air brake tests.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Single car air brake tests. 232.305 Section 232.305...and Testing Requirements § 232.305 Single car air brake tests. (a) Single car air brake tests shall be performed by a...

2011-10-01

152

49 CFR 393.49 - Control valves for brakes.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Control valves for brakes. 393.49 Section 393...OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. ...system so arranged that one application valve must when activated cause all of...

2011-10-01

153

49 CFR 393.49 - Control valves for brakes.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Control valves for brakes. 393.49 Section 393...OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. ...system so arranged that one application valve must when activated cause all of...

2012-10-01

154

Experimental Identification of Brake Pad Material Properties-A Step Towards a Better Prediction of Brake Squeal  

NASA Astrophysics Data System (ADS)

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.

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

2010-09-01

155

Engineering Report. Part 3: Nasa Lightweight Wheel and Brake sub-System. Lightweight Brake Development.  

National Technical Information Service (NTIS)

The development of light weight wheel and brake systems designed to meet the space shuttle type requirements was investigated. The study includes the use of carbon graphite composite and beryllium as heat sink materials and the compatibility of these heat...

L. D. Bok

1973-01-01

156

The effect of aftermarket linings on braking efficiency  

SciTech Connect

Currently there are no adequate standards or regulations that address the performance of aftermarket replacement brake linings to insure that the use of these materials does not degrade vehicle braking performance from the original equipment (OE) design intent level. This paper discusses the results of an evaluation of a large sampling of aftermarket linings available for the rear brake of a specific model passenger car and shows that many of these linings have significantly different performance than the OE material. The paper also shows how this deviation can adversely affect vehicle braking efficiency or the ability of the brake system to utilize available tire/roadway friction without locking wheels and losing control.

Flick, M.A.; Radlinski, R.W.; Kirkbride, R.L.

1987-01-01

157

Muzzle Brake for an Underwater Gun.  

National Technical Information Service (NTIS)

A device for use as a muzzle brake for an underwater gun having a projectile conveying structure with concentric inner and outer cylinders. The inner cylinder has at least one longitudinal slot formed therein. A sealing means joins the projectile conveyin...

I. N. Kirschner G. R. Berlam

1997-01-01

158

An experimental study of perforated muzzle brakes  

Microsoft Academic Search

A firing test was conducted to examine the recoil efficiency and blast characteristics of perforated muzzle brakes fitted to a 20 mm cannon. Recoil impulse blast overpressures, muzzle velocity, sequential spark shadowgraphs, and photographs of the muzzle flash structure were obtained. Three different nuzzle devices were used with one device equipped with pressure transducers to measure the static pressure in

R. E. Dillon Jr.; H. T. Nagamatsu

1984-01-01

159

A parametric study of perforated muzzle brakes  

Microsoft Academic Search

A firing test was conducted to study the parameters influencing the recoil efficiency and the blast characteristics of perforated muzzle brakes. Several scaled (20 mm) devices were tested as candidates for the 105 mm Armored Gun System (AGS). Recoil impulse, blast overpressures, muzzle velocity, sequential spark shadowgraphs, and photographs of the muzzle flash were obtained. A total of nine different

Robert E. Dillon Jr.; H. T. Nagamatsu

1993-01-01

160

Pedestrian injury mitigation by autonomous braking  

Microsoft Academic Search

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

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

2010-01-01

161

Motor Vehicle Brake Fluids Test Report.  

National Technical Information Service (NTIS)

The report includes the procedure and data relative to brake fluid tests performed in November and December of 1968 on the following automobiles: (1) Dodge Charger - Chrysler Part 242 1352 - Hi Temp.; (2) Plymouth Sport Fury - Chrysler Part 293 - 3249; (3...

1969-01-01

162

Hooggeplaatste Remlichten (High-Mounted Brake Lights).  

National Technical Information Service (NTIS)

A literature review is presented of the effects of one or two extra brake lights in or on cars at the height of the rear window. The greatest care should be exercised in the evaluation of the estimated effect. There are some indications that the effect ca...

J. A. G. Mulder

1984-01-01

163

Pedestrian injury mitigation by autonomous braking.  

PubMed

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

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

2010-06-25

164

Model-based analysis of the mechanical subsystem of an air brake system  

Microsoft Academic Search

Most commercial vehicles such as buses and trucks use an air brake system, often equipped with an S-cam drum brake, to reduce\\u000a their speed and\\/or to stop. With a drum brake system, the clearance between the brake shoe\\/pad and the brake drum may increase\\u000a because of various reasons such as wearing of the brake shoe and\\/or brake drum and drum

D. B. Sonawane; K. Narayan; V. S. Rao; S. C. Subramanian

2011-01-01

165

Excitation Method of Linear-Motor-Type Rail Brake without Using Power Sources by Dynamic Braking with Zero Electrical Output  

NASA Astrophysics Data System (ADS)

The eddy current rail brake is a type of braking system used in railway vehicles. Because of problems such as rail heating and problems associated with ensuring that power is supplied when the feeder malfunctions, this braking system has not been used for practical applications in Japan. Therefore, we proposed the use of linear induction motor (LIM) technology in eddy current rail brake systems. The LIM rail brake driven by dynamic braking can reduce rail heating and generate the energy required for self-excitation. In this paper, we present an excitation system and control method for the LIM rail brake driven by “dynamic braking with zero electrical output”. The proposed system is based on the concept that the LIM rail brake can be energized without using excitation power sources such as a feeder circuit and that high reliability can be realized by providing an independent excitation system. We have studied this system and conducted verification tests using a prototype LIM rail brake on a roller rig. The results show that the system performance is adequate for commercializing the proposed system, in which the LIM rail brake is driven without using any excitation power source.

Sakamoto, Yasuaki; Kashiwagi, Takayuki; Hasegawa, Hitoshi; Sasakawa, Takashi; Fujii, Nobuo

166

Hydraulic flywheel  

SciTech Connect

A pair of separable sections forming a hollow structure are coupled to a rotatable shaft. Controlled quantities of hydraulic fluid are introduced into the hollow structure through a passageway within the shaft. One of the sections is selectively slidable along the shaft, for release of fluid from within the structure.

Maxwell, T.J.

1982-06-22

167

Integrated hydraulic system  

SciTech Connect

An integrated hydraulic system is described for a vehicle having a propulsion engine comprising a first fixed capacity or displacement hydraulic pump. A steering mechanism hydraulically operating circuit supplies the hydraulic fluid delivered by the first hydraulic pump into a steering mechanism. It also comprises a second fixed capacity or displacement hydraulic pump. A work implement hydraulically operating circuit selectively supplies the hydraulic fluid delivered by the second hydraulic pump through a pilot operated directional control valve into the steering mechanism hydraulically operating circuit and/or the work implement hydraulically operating circuit.

Karakama, T.

1987-01-06

168

Braking hazards of golf cars and low speed vehicles.  

PubMed

Research and analysis of braking issues for golf cars and other low speed vehicles (LSVs) are reported in this study. It is shown that many such vehicles only provide braking for their rear wheels, which can lead to a driver losing control during travel on typical steep downgrades. The braking performance of a golf car equipped with brakes on two or four wheels was analyzed to determine the effects of two and four wheel brake designs on braking efficiency and vehicle yaw stability. Besides reducing braking efficiency, it is demonstrated that installing brakes on only the rear wheels can lead to directional instability (fishtailing) and rollover when the rear wheels are braked until skidding occurs. The nonexistence of golf course standards and the inadequacy of golf car and LSV standards are noted and a connection between this and the comparatively high level of accidents with such vehicles is inferred. Based on these results, it is advisable to install brakes on all four wheels of golf cars and LSVs. In addition, new safety standards should be considered to reduce the occurrence of golf car accidents on steep downhill slopes. PMID:16806027

Seluga, K J; Ojalvo, I U

2006-06-27

169

Hydraulic systems performance of Army engine oils  

SciTech Connect

A technical evaluation of qualified military specification lubricants was started by the U.S. Army Belvoir Research and Development Center and was performed at the U.S. Army Fuels and Lubricants Research Laboratory (AFLRL) located at Southwest Research Institute. This work was conducted to determine if such lubricants can be used as hydraulic fluids in Army Commercial Construction Equipment (CCE) and Selected Material Handling Equipment (SMHE). Sixteen military specification lubricants were extensively evaluated using twelve selected tests required by equipment manufacturers and one test developed by AFLRL in conjunction with John Deere. From the data developed, lubricants meeting Army specifications passed 88 percent of all the tests. It appears that the Army engine oils are good potential candidates for use as hydraulic and power transmission lubricants within the Army CCE/SMHE systems. Areas of concern include copper corrosion, wet brake/clutch frictional performance, and final drive gear wear.

Marbach, H.W.; Lestz, S.J.

1984-01-01

170

Development of a model for an air brake system with leaks  

Microsoft Academic Search

Brake systems in trucks are crucial for ensuring the safety of vehicles and passengers on the roadways. Most trucks in the US are equipped with S-cam drum brake systems and they are sensitive to maintenance. Brake defects such as leaks are a major cause of accidents involving trucks. Leaks in the air brake systems affect braking performance drastically by decreasing

Srivatsan Ramarathnam; Sandeep Dhar; Swaroop Darbha; K. R. Rajagopal

2009-01-01

171

Prediction of brake friction materials recovery performance using artificial neural networks  

Microsoft Academic Search

The brake friction materials in an automotive brake system are considered as one of the key components for overall braking performance of a vehicle. The sensitivity of friction material performance and accordingly brake performance, versus different operating regimes, has always been an important aspect of its functioning. In this paper, the influences not only on the brake operation conditions but

Dragan Aleksendri?; David C. Barton; Branko Vasi?

2010-01-01

172

Design of a PZT-actuated proportional drum brake  

Microsoft Academic Search

Presents the design of a piezoelectric-ceramic (PZT)-stack-actuated brake that is similar to a magnetic particle brake in dynamic range, size, weight, and cost, while providing a significantly larger bandwidth and requiring significantly less electrical power for a given continuous torque output. The device is essentially a single-pad drum brake that is actuated with a PZT-stack actuator. A significant component of

Michael Gogola; Michael Goldfarb

1999-01-01

173

Tribological performance of brake friction materials containing carbon nanotubes  

Microsoft Academic Search

This study examined brake friction materials containing multi-wall carbon nanotubes (CNTs) to determine their effect on the braking performance. The friction materials were produced using conventional dry mixing methods by substituting barite with CNTs (1.7, 4.7, and 8.5wt.%). Their tribological properties were examined using both a Krauss type tester and a 1\\/5 scale brake dynamometer. The physical and tribological properties

H. J. Hwang; S. L. Jung; K. H. Cho; Y. J. Kim; H. Jang

2010-01-01

174

Tau as a Potential Control Variable for Visually Guided Braking  

ERIC Educational Resources Information Center

|D. N. Lee (1976) described a braking strategy based on optical expansion in which the driver brakes so that the target's time-to-contact declines around a constant slope in the range -0.5 less than or equal to tau less than 0. The present results from a series of braking simulations confirm and extend earlier reports (E. H. Yilmaz & W. H. Warren,…

Rock, Paul B.; Harris, Mike G.

2006-01-01

175

Antimony in brake pads-a carcinogenic component?  

Microsoft Academic Search

Antimony trisulfide (Sb2S3) is used as a lubricant in friction material. X-ray diffraction analysis revealed Sb in 3\\/3 disc brake pads (range 41,000–46,000 mg\\/kg) and in 2\\/2 disc brake dust samples (21,000 and 17,000 mg\\/kg) from trucks. Considerably lower concentrations were found in drum brake pads (3\\/5, 59–6400 mg\\/kg) and in drum brake dust (4\\/18, 78–2800 mg\\/kg). Other toxic metals

Ole von Uexküll; Staffan Skerfving; Reed Doyle; Michael Braungart

2005-01-01

176

49 CFR 238.15 - Movement of passenger equipment with power brake defects.  

Code of Federal Regulations, 2012 CFR

...axles for the purposes of calculating the percentage of operative brakes. Unless otherwise specified by the railroad, the friction braking effort over all other axles shall be considered uniform. (iv) The following brake conditions not in...

2012-10-01

177

49 CFR 238.15 - Movement of passenger equipment with power brake defects.  

Code of Federal Regulations, 2011 CFR

...axles for the purposes of calculating the percentage of operative brakes. Unless otherwise specified by the railroad, the friction braking effort over all other axles shall be considered uniform. (iv) The following brake conditions not in...

2011-10-01

178

30 CFR 75.1403-2 - Criteria-Hoists transporting materials; brakes.  

Code of Federal Regulations, 2010 CFR

...Criteria-Hoists transporting materials; brakes. 75.1403-2 Section...Hoists transporting materials; brakes. Hoists and elevators used to transport materials should be equipped with brakes capable of stopping...

2010-07-01

179

30 CFR 75.1403-2 - Criteria-Hoists transporting materials; brakes.  

Code of Federal Regulations, 2010 CFR

...Criteria-Hoists transporting materials; brakes. 75.1403-2 Section...Hoists transporting materials; brakes. Hoists and elevators used to transport materials should be equipped with brakes capable of stopping...

2009-07-01

180

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

Code of Federal Regulations, 2012 CFR

...Process to introduce new brake system technology. 232.503 Section 232.503... Introduction of New Brake System Technology § 232.503 Process to introduce new brake system technology. (a) Pursuant to the...

2012-10-01

181

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

Code of Federal Regulations, 2012 CFR

... Handling of defective equipment with ECP brake systems. 232.609 Section 232... Electronically Controlled Pneumatic (ECP) Braking Systems § 232.609 Handling of defective equipment with ECP brake systems. (a)...

2012-10-01

182

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

Code of Federal Regulations, 2011 CFR

... Handling of defective equipment with ECP brake systems. 232.609 Section 232... Electronically Controlled Pneumatic (ECP) Braking Systems § 232.609 Handling of defective equipment with ECP brake systems. (a)...

2011-10-01

183

49 CFR 393.45 - Brake tubing and hoses; hose assemblies and end fittings.  

Code of Federal Regulations, 2012 CFR

...false Brake tubing and hoses; hose assemblies and end fittings. 393.45 Section...45 Brake tubing and hoses; hose assemblies and end fittings. (a) General...construction requirements for tubing and hoses, assemblies, and end fittings. All brake...

2012-10-01

184

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

Code of Federal Regulations, 2011 CFR

...Process to introduce new brake system technology. 232.503 Section 232.503... Introduction of New Brake System Technology § 232.503 Process to introduce new brake system technology. (a) Pursuant to the...

2011-10-01

185

49 CFR 229.29 - Air brake system calibration, maintenance, and testing.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Air brake system calibration, maintenance, and testing. 229...Tests § 229.29 Air brake system calibration, maintenance, and testing. (a...locomotive's air brake system shall receive the calibration, maintenance, and testing...

2012-10-01

186

Simulation and test on braking performance of heavy-duty truck with multi-axis braking system  

Microsoft Academic Search

Based on multi-body dynamic method, a combined braking system model with two disc brakes and four drum brakes were built. On the basis of this model, a rigid-flexible coupling model of a heavy-duty truck with full-floating cab mount system, air suspension system with four air springs and taper-leaf-spring system was built. Some simulation calculations were performed in ADAMS software environment

He Hao; Dengfeng Wang; Shuming Chen; Shengqiang Liu; Shaoxian Bu

2010-01-01

187

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

Microsoft Academic Search

The actual regenerative braking force of an integrated starter\\/generator (ISG), which is varied with desired braking deceleration\\u000a and vehicle speed, is calculated based on an analysis of the required deceleration, maximum braking force of ISG, engine braking\\u000a force and state of charge (SOC) of battery. Braking force distribution strategies are presented according to the actual regenerative\\u000a braking force of ISG.

Datong Qin; Ming Ye; Zhenjun Liu

2007-01-01

188

A study on regenerative braking for a parallel hybrid electric vehicle  

Microsoft Academic Search

In this paper, a regenerative braking algorithm is presented and performance of a hybrid electric vehicle (HEV) is investigated.\\u000a The regenerative braking algorithm calculates the available regenerative braking torque by considering the motor characteristics,\\u000a the battery SOC and the CVT speed ratio. When the regenerative braking and the friction braking are applied simultaneously,\\u000a the friction braking torque corresponding to the

Sungwook Jang; Hoon Yeo; Chulsoo Kim; Hyunsoo Kim

2001-01-01

189

Copper leaching from brake wear debris in standard extraction solutions.  

PubMed

Quantification of the copper content of and copper leaching from a disc brake wear debris sample was performed using microwave-assisted acid digestion, the Federal Toxicity Characteristic Leaching Procedure (TCLP), and the State of California Waste Extraction Test (WET). The brake wear debris tested was a composite sample obtained from a brake dynamometer test of one brake pad source material. Comparative digestion studies demonstrated that a modified aqua regia matrix (HNO3:HCl:H2O2 = 1:3:0.5) optimized the digestion effectiveness for determining the total copper content in the brake wear debris. No significant sample heterogeneity within the brake wear debris was observed, based on statistically indistinguishable total copper content results for subsamples with a wide range of sample masses. Upon pooling all subsample results, an overall total copper content for the composite brake wear debris sample was determined to be 10.8% (g/g), with a 95% confidence limit of +/- 0.5% (g/g). Copper leaching increased with decreasing solid-to-liquid ratios in TCLP tests, but was unaffected by the solid-to-liquid ratio in the WET. For a 1:10(4) (g/g) solid-to-liquid ratio, 85% and 99% of the total mass of copper present in the composite brake wear debris sample was leached into solution during the TCLP and WET, respectively. Rate studies also demonstrated that the WET resulted in a faster rate and higher extent of copper leaching relative to the TCLP. Compared to reference copper-containing materials, the composite brake wear debris sample exhibited relatively higher TCLP and WET copper leaching characteristics. The higher copper leaching exhibited by the brake wear debris sample may have resulted from its higher specific surface area and/or from changes in the chemical form of copper that occurred during the braking process. PMID:14587858

Hur, Jin; Yim, Soobin; Schlautman, Mark A

2003-10-01

190

Optical classification for quality and defect analysis of train brakes  

NASA Astrophysics Data System (ADS)

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.

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

2009-06-01

191

From the Kinetic Energy Recovery System to the Thermo-Hydraulic Hybrid Motor Vehicle  

NASA Astrophysics Data System (ADS)

The paper presents some theoretical and experimental results obtained by the Hydraulics and Pneumatics Research Institute INOE 2000-IHP with its partners, regarding the creating of one hydraulic system able to recovering the kinetic energy of the motor vehicles, in the braking phases, and use this recovered energy in the starting and accelerating phases. Also, in the article is presented a testing stand, which was especially designed for testing the hydraulic system for recovery the kinetic energy. Through mounting of the kinetic energy recovering hydraulic system, on one motor vehicle, this vehicle became a thermo-hydraulic hybrid vehicle. Therefore, the dynamic behavior was analyzed for the whole hybrid motor vehicle, which includes the energy recovery system. The theoretical and experimental results demonstrate the possible performances of the hybrid vehicle and that the kinetic energy recovery hydraulic systems are good means to increase energy efficiency of the road motor vehicles and to decrease of the fuel consumption.

Cristescu, Corneliu; Drumea, Petrin; Guta, Dragos; Dumitrescu, Catalin

2011-12-01

192

Development of a co-operative control algorithm during regenerative braking for a fuel cell electric vehicle  

Microsoft Academic Search

In this study, a regenerative braking control algorithm was developed for the fuel cell electric vehicle (FCEV) equipped with the front electronic wedge brake (EWB). A regenerative braking control algorithm was proposed for the regenerative braking and friction braking for the front wheels, and for the friction braking for the rear wheels; and a powertrain model of an FCEV composed

Jiweon Ko; Jungwook Kim; Gaeun Lee; Sunggon Byun; Dongyoon Hyun; Hyunsoo Kim

2011-01-01

193

Hydraulic fracturing-1  

SciTech Connect

This book contains papers on hydraulic fracturing. Topics covered include: An overview of recent advances in hydraulic fracturing technology; Containment of massive hydraulic fracture; and Fracturing with a high-strength proppant.

Not Available

1990-01-01

194

Numerical Simulation and Experimental Test on Muzzle Brake Efficiency  

Microsoft Academic Search

Numerical simulation and firing test of a gun was performed to give the muzzle brake efficiency and pressure of muzzle blast wave for evaluating the muzzle brake performance. Two models of muzzle flow were given respectively with Euler equations ignore initial flow field and Navier-Stokes equations with turbulence model consider initial flow field. Numerical simulation was carried out and simulation

Kun Jiang; Hao Wang

2011-01-01

195

49 CFR 570.6 - Brake power unit.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Brake power unit. 570.6 Section 570.6 Transportation...000 Pounds or Less § 570.6 Brake power unit. (a) Vacuum hoses shall...started, demonstrating integrity of the power assist system. This test is not...

2011-10-01

196

Positive safety brake for oil well pumping apparatus  

Microsoft Academic Search

A safety brake adapted for positively locking the crank and counter-balance weights of oil well pumping apparatus against rotation, particularly for placement and servicing of the pumping unit is described. In the preferred embodiment shown, a cylindrical member is bolted to a brake drum which rotates in combination with the shaft from the gear box carrying the crank and counter-balance

1981-01-01

197

Wear performance and wear debris of semimetallic automotive brake materials  

Microsoft Academic Search

Wear performance of automotive brake material is addressed and debris collected after brake dynamometer test and after ball-milling of identical semimetallic friction lining is characterized using a combination of analytical techniques. The differences between dynamometer wear debris and ball-milled samples are demonstrated. Wear debris is typified by the presence of numerous nanoparticles formed during wear process. Their chemistry resembles the

Jana Kukutschová; Václav Roubí?ek; Miroslav Mašlá?; Dalibor Jan?ík; Václav Slovák; Kate?ina Malachová; Zuzana Pavlí?ková; Peter Filip

2010-01-01

198

Oxygen-diffused titanium as a candidate brake rotor material  

Microsoft Academic Search

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 –

Jun Qu; Peter Julian Blau; Brian C. Jolly

2009-01-01

199

Towards a better understanding of brake friction materials  

Microsoft Academic Search

This work focuses on surface changes induced by repeated brake applications and tries to provide explanations, how such material modifications might affect friction and wear properties of automotive disc brakes. Surface films were investigated locally by transmission electron microscopy (TEM) after having prepared thin cross-sections with a focused ion beam instrument (FIB). Since the observed friction layers revealed a nanocrystalline

W. Österle; H. Kloß; I. Urban; A. I. Dmitriev

2007-01-01

200

Numerical simulation of typical contact situations of brake friction materials  

Microsoft Academic Search

In the paper, a model typical for contact situations of automotive brakes is established based on the method of movable cellular automata. The processes taking place at local contacts in an automotive brake system are analysed. Based on microscopic and micro-analytical observations, the following contact situations were simulated: (i) a couple of ferritic steel against pearlitic steel, both covered by

A. I. Dmitriev; W. Österle; H. Klo?

2008-01-01

201

Research on control for regenerative braking of electric vehicle  

Microsoft Academic Search

The limitation of driving range is the key restriction for the development of EV (electric vehicle), and regenerative braking is an effective approach to extend the driving range of electric vehicle. To protect the battery from broken caused by large charging current during regenerative braking, the control strategy that makes the charging current as control object is proposed in this

Binggang Cao; Zhifeng Bai; Wei Zhang

2005-01-01

202

Fuzzy logic based automatic braking system in trains  

Microsoft Academic Search

This paper focuses on a new approach to braking system in train, by the using the technique of artificial intelligence applied to it. The intelligence for braking is provided by a fuzzy logic controller. The fuzzy logic controller is simulated using Matlab-Simulink fuzzy logic toolbox. Generally the Indian railways use two persons to operate a train and they employ a

G. Sankar; S. Saravana Kumar

2006-01-01

203

A fuzzy logic controller for an ABS braking system  

Microsoft Academic Search

Anti-blocking system (ABS) brake controllers pose unique challenges to the designer: a) For optimal performance, the controller must operate at an unstable equilibrium point, b) Depending on road conditions, the maximum braking torque may vary over a wide range, c) The tire slippage measurement signal, crucial for controller performance, is both highly uncertain and noisy, d) On rough roads, the

Georg F. Mauer

1995-01-01

204

49 CFR 570.58 - Electric brake system.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Electric brake system. 570.58 ...DEPARTMENT OF TRANSPORTATION VEHICLE IN USE INSPECTION STANDARDS Vehicles With GVWR of More Than 10,000 Pounds § 570.58 Electric brake system. (a)...

2012-10-01

205

49 CFR 236.507 - Brake application; full service.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Brake application; full service. 236.507 Section 236.507...Standards § 236.507 Brake application; full service. The automatic train stop or...apparatus shall, when operated, cause a full service application of the...

2012-10-01

206

49 CFR 236.507 - Brake application; full service.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Brake application; full service. 236.507 Section 236.507...Standards § 236.507 Brake application; full service. The automatic train stop or...apparatus shall, when operated, cause a full service application of the...

2011-10-01

207

How Things Work: Front and Rear Bicycle Brakes  

NSDL National Science Digital Library

This site from How Things Work, by Lou Bloomfield, provides an explanation of why it can be hard to stop a bike with the rear brakes alone. The site contains a description of how friction and torque produce a rotation of the bicycle that makes the rear brakes ineffective.

2006-11-08

208

Control of asbestos exposure during brake drum service  

SciTech Connect

Earlier studies of airborne asbestos exposure to mechanics during brake maintenance operations showed overexposure to asbestos fibers during brake servicing, especially brake assembly cleaning. Because an estimated 150,000 brake mechanics and garage workers in the U.S. are potentially exposed to asbestos, a known carcinogen, and the lack of information available on the effectiveness of available controls, an evaluation of these methods was initiated. Detailed field surveys were conducted at five facilities employing five methods for controlling exposure to asbestos during brake repair. These included the use of two commercial enclosure devices with ventilation provided by HEPA filter-equipped vacuum, a HEPA filter-equipped vacuum alone, a brush with recirculating cleaning solution, and cleaning solvents in aerosol cans. These controls were evaluated while servicing brakes to automobiles, pickup trucks, vans, and vehicles with a 4-wheel rear axle. Detailed evaluations of these control measures involved a program consisting of traditional air sampling methods, incorporating phase contrast microscopy (PCM) and transmission electron microscopy (TEM), and a real-time analysis of brake dust exposure. Personal and area air samples were collected during brake repair to each vehicle.

Sheehy, J.W.; Cooper, T.C.; O'Brien, D.M.; McGlothlin, J.D.; Froehlich, P.A.

1989-08-01

209

On the nature of tribological contact in automotive brakes  

Microsoft Academic Search

The tribological contact in automotive brakes involves dry sliding contact at high speeds and high contact forces. The commonly used organic binder-type brake pad friction materials are extremely inhomogeneous and exhibit very low bulk strengths. Despite the low strength, the specific contact surfaces that form during the use render the pads very good friction and wear characteristics. This paper gives

Mikael Eriksson; Filip Bergman; Staffan Jacobson

2002-01-01

210

The antilock braking system anomaly: a drinking driver problem?  

PubMed

Antilock braking systems (ABS) have held promise for reducing the incidence of accidents because they reduce stopping times on slippery surfaces and allow drivers to maintain steering control during emergency braking. Farmer et al. (Accident Anal. Prevent. 29 (1997) 745) provide evidence that antilock brakes are beneficial to nonoccupants: a set of 1992 model General Motors vehicles equipped with antilock brakes were involved in significantly fewer fatal crashes in which occupants of other vehicles, pedestrians, or bicyclists were killed. But, perversely, the risk of death for occupants of vehicles equipped with antilock brakes increased significantly after adoption. Farmer (Accident Anal. Prevent. 33 (2001) 361) updates the analysis for 1996- 1998 and finds a significant attenuation in the ABS anomaly. Researchers have put forward two hypotheses to explain this antilock brake anomaly: risk compensation and improper operation of antilock brake-equipped vehicles. We provide strong evidence for the improper operation hypothesis by showing that the antilock brake anomaly is confined largely to drinking drivers. Further, we show that the attenuation phenomenon occurs consistently after the first three to four years of vehicle service. PMID:11939362

Harless, David W; Hoffer, George E

2002-05-01

211

DC torque motor actuated anti-lock brake controller  

SciTech Connect

A wheel lock control system is described for limiting the brake pressure applied to the brake of a vehicle wheel traveling over a road surface, the system comprising: an actuator for controlling the brake pressure to the brake of the wheel, the actuator including a torque motor for generating a motor torque in response to motor current to control the applied brake pressure in accordance with the value of the motor torque, the motor torque having a value proportional to the value of the motor current; means for determining the tire torque tending to accelerate the wheel during the application of brake pressure; means for storing the value of motor current corresponding to the maximum determined value of tire torque; means for detecting an incipient wheel lockup condition; and means for establishing the motor current following a detected incipient wheel lockup condition at a value having a predetermined relationship to the stored value of motor current to control the brake pressure at a predetermined braking condition.

Agarwal, P.D.; Kade, A.

1989-02-21

212

Robust control of anti-lock brake system  

Microsoft Academic Search

A robust control algorithm for an anti-lock brake system is proposed. The method used is based on static-state feedback of longitudinal slip and does not involve controller scheduling with changing vehicle speed or road adhesion coefficient estimation. An improvement involving scheduling of longitudinal slip reference with longitudinal acceleration measurement is included. Electromechanical braking actuators are used in simulations, and the

?. Emre Köse; Günay Anla?

2007-01-01

213

Brake Fluid Vapor Lock Temperatures vs Equilibrium Reflux Boiling Points.  

National Technical Information Service (NTIS)

Vapor lock temperatures (VLT) were determined on dry and humidified samples of all brake fluids listed on the Qualified Products List of Federal Specification VV-B-680, Brake Fluid Automotive, and compared to the equilibrium reflux boiling points (ERBP) o...

C. B. Jordan R. G. Jamison

1974-01-01

214

Fueling active galactic nuclei by magnetic braking  

SciTech Connect

Recent detections of massive concentrations of molecular gas near the centers of galaxies hosting active nuclei suggest that these concentrations may be the source of accretion fuel for the nucleus. However, for that to be true, an angular momentum barrier must be overcome before the material in such a cloud can reach the nucleus. It is suggested that magnetic braking of the cloud may remove sufficient angular momentum to permit its material to draw considerably closer to the central object. The mechanism is particularly effective in the limit that the gas becomes self-gravitating because removal of a fraction of the initial angular momentum can lead to dynamical instability and collapse. Any small misalignment between the initial rotation axis of the cloud and the rotation axis of the galaxy can be substantially amplified as a result of the braking. It is argued that mass accretion onto the central object may occur in episodes, in some cases with a constant mass accretion rate during each episode. 32 refs.

Krolik, J.H.; Meiksin, A. (Johns Hopkins Univ., Baltimore, MD (USA))

1990-04-01

215

Optimal design of a hybrid MR brake for haptic wrist application  

NASA Astrophysics Data System (ADS)

In this work, a new configuration of a magnetorheological (MR) brake is proposed and an optimal design of the proposed MR brake for haptic wrist application is performed considering the required braking torque, the zero-field friction torque, the size and mass of the brake. The proposed MR brake configuration is a combination of disc-type and drum-type which is referred as a hybrid configuration in this study. After the MR brake with the hybrid configuration is proposed, braking torque of the brake is analyzed based on Bingham rheological model of the MR fluid. The zero-field friction torque of the MR brake is also obtained. An optimization procedure based on finite element analysis integrated with an optimization tool is developed for the MR brake. The purpose of the optimal design is to find the optimal geometric dimensions of the MR brake structure that can produce the required braking torque and minimize the uncontrollable torque (passive torque) of the haptic wrist. Based on developed optimization procedure, optimal solution of the proposed MR brake is achieved. The proposed optimized hybrid brake is then compared with conventional types of MR brake and discussions on working performance of the proposed MR brake are described.

Nguyen, Quoc Hung; Nguyen, Phuong Bac; Choi, Seung-Bok

2011-03-01

216

Modeling of automotive drum brakes for squeal and parameter sensitivity analysis  

Microsoft Academic Search

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

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

2006-01-01

217

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

Code of Federal Regulations, 2010 CFR

...the lining is so marked, for air drum brakes. The steering axle brake lining...measured at the shoe center for drum brakes); or less than 3.2 mm (1...at the shoe center) for disc or drum brakes. (e) Clamp and...

2009-10-01

218

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

Code of Federal Regulations, 2010 CFR

...the lining is so marked, for air drum brakes. The steering axle brake lining...measured at the shoe center for drum brakes); or less than 3.2 mm (1...at the shoe center) for disc or drum brakes. (e) Clamp and...

2010-10-01

219

Braking technique research on high power permanent magnet brushless motor of aviation  

Microsoft Academic Search

For braking problems of high power BLDCM on aviation, with the characteristics of air power supply, this paper respectively studies the change of phase current in dynamic braking and plug breaking. It compares the speed performance of the different braking methods, and proposes using different phase current detection ways for different braking methods and the phase current control method based

Bo Tan; Ruiqing Ma; Weiguo Liu; Jun Zhao

2010-01-01

220

Design and Control Principles of Hybrid Braking System for EV, HEV and FCV  

Microsoft Academic Search

Due to the introduction of electrical regenerative braking, the structure, design and control of braking system of an electric vehicle (EV), hybrid electrical vehicle (HEV) and fuel cell vehicle (FCV) is quite different from the pure mechanical braking system of conventional vehicles. Desirable braking performance not only guarantee to quickly stop the vehicle and maintain the traveling direction stable and

Yimin Gao; Liang Chu; M. Ehsani

2007-01-01

221

The Reliability Modeling and Analysis on Brake System of Medium-low Speed Maglev Train  

Microsoft Academic Search

The object of the paper is the reliability of the function of the brake system on Beijing S1 line Medium-low Speed Maglev Train. The construction of the brake system and the working principle of the brake system are analyzed, based on which, the reliability of the emergency brake function is analyzed via FTA method after modeling, then the weakness of

Qinglong Tan; Hongfeng Qi; Jiangsuo Li; Ying Tian

2012-01-01

222

Airborne asbestos exposure during light aircraft brake replacement.  

PubMed

Asbestos containing materials are a component of many vehicle brake systems, including those found in some light aircraft. To characterize the asbestos exposure that results from the installation and maintenance of these components, an aircraft fitted with asbestos containing brake pads had brake changes performed while both area and personal air samples were taken. The brake changing process took place in a closed, unventilated aircraft hanger and all operations were performed according to the manufacturer's recommended procedure. Personal air samples did not detect any measurable amount of asbestos fibers during the brake changing or subsequent cleanup procedures. Analysis of personal samples (n=9) using phase contrast microscopy indicated airborne fiber concentrations at or below 0.003f/ml as 8-h time weighted averages (TWAs) and less than 0.069f/ml averaged over 28-30min sampling periods. Airborne chrysotile fibers were detected by two area air samples with fiber concentrations remaining at or below 0.0013f/ml over an 8-h TWA. These results indicate that normal brake changing work practices on aircraft with asbestos containing brake pads does not produce a harmful level of asbestos exposure for aircraft mechanics. PMID:19409949

Blake, Charles L; Johnson, Giffe T; Harbison, Raymond D

2009-05-04

223

Vehicle Hybrid Braking Control Using Sliding Mode Control  

NASA Astrophysics Data System (ADS)

Anti-lock brake system and brake-by-wire are proposed in the vehicle control using a brake, and the braking power is expected to be improved more than ever. The researches such as an application to the ABS of Siliding mode control which considered a actuator dynamics and a hybrid control of the brake using model reference adaptive control are done so far. However, in the former case, speed following that becomes a target exists physically impossible situation by saturation of tire frictional force because only speed following is done. In the latter, the model error is caused because the simulation model and the controller design model are different. Therefore, there is a problem that an accurate follow cannot be done. In this paper, the braking control is performed using the sliding mode control which has high robustness for disturbance that fulfils matching conditions. In so doing, it aims at the achievement of optimal braking control to switch wheel speed following to slip ratio following.

Kasahara, Misawa; Kanai, Yuki; Shiraki, Ryoko; Mori, Yasuchika

224

Braking electric-powered wheelchairs: Effect of braking method, seatbelt, and legrests  

Microsoft Academic Search

Objective: To examine the influence of three electric-powered wheelchair braking conditions and four wheelchair seating conditions on electric-powered wheelchair motion and Hybrid II test dummy motion. This study provides quantitative information related to assessing the safety of electric-powered wheelchair driving.Design: Rehabilitation engineering comparison and ANSI\\/RESNA standards testing. Convenience sample of eight different electric-powered wheelchairs. Within-chair comparisons were conducted.Intervention: Electric-powered wheelchairs

Rory A. Cooper; Michael J. Dvorznak; Thomas J. O'Connor; Michael L. Boninger; Daniel K. Jones

1998-01-01

225

Cycling and wind: does sidewind brake?  

NASA Astrophysics Data System (ADS)

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

Íńiguez-de-la-Torre, I.; Íńiguez, J.

2006-01-01

226

Residual stresses in a cast iron automotive brake disc rotor  

NASA Astrophysics Data System (ADS)

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.

Ripley, Maurice I.; Kirstein, Oliver

2006-11-01

227

Optimal design of a hybrid MR brake for haptic wrist application  

Microsoft Academic Search

In this work, a new configuration of a magnetorheological (MR) brake is proposed and an optimal design of the proposed MR brake for haptic wrist application is performed considering the required braking torque, the zero-field friction torque, the size and mass of the brake. The proposed MR brake configuration is a combination of disc-type and drum-type which is referred as

Quoc Hung Nguyen; Phuong Bac Nguyen; Seung-Bok Choi

2011-01-01

228

Optimal Design of a T-Shaped Drum-Type Brake for Motorcycle Utilizing Magnetorheological Fluid  

Microsoft Academic Search

This research focuses on developing a new configuration and optimal design of magnetorheological (MR)-fluid-based brake (MR brake in short) for a middle-sized motorcycle that can replace conventional drum-type brake. A novel configuration featuring a T-shaped drum and a hybrid concept of magnetic circuit (using both axial and radial magnetic flux) to generate braking force is proposed for the MR brake.

Nguyen Q. Hung; Choi S. Bok

2012-01-01

229

Driver Behavioral Changes through Interactions with an Automatic Brake System for Collision Avoidance  

NASA Astrophysics Data System (ADS)

This paper discusses driver's behavioral changes as a result of driver's use of an automatic brake system for preventing a rear-end collision from occurring. Three types of automatic brake systems are investigated in this study. Type 1 brake system applies a strong automatic brake when a collision is very imminent. Type 2 brake system initiates brake operation softly when a rear-end crash may be anticipated. Types 1 and 2 are for avoidance of a collision. Type 3 brake system, on the other hand, applies a strong automatic brake to reduce the damage when a collision can not be avoided. An experiment was conducted with a driving simulator in order to analyze the driver's possible behavioral changes. The results showed that the time headway (THW) during car following phase was reduced by use of an automatic brake system of any type. The inverse of time to collision (TTC), which is an index of the driver's brake timing, increased by use of Type 1 brake system when the deceleration rate of the lead vehicle was relatively low. However, the brake timing did not change when the drivers used Type 2 or 3 brake system. As a whole, dangerous behavioral changes, such as overreliance on a brake system, were not observed for either type of brake system.

Itoh, Makoto; Fujiwara, Yusuke; Inagaki, Toshiyuki

230

49 CFR 232.109 - Dynamic brake requirements.  

Code of Federal Regulations, 2010 CFR

...the controlling (lead) position of a consist unless the locomotive has the capability of: (1) Controlling the dynamic braking effort in trailing locomotives in the consist that are so equipped; and (2) Displaying to the locomotive...

2009-10-01

231

49 CFR 232.109 - Dynamic brake requirements.  

Code of Federal Regulations, 2010 CFR

...the controlling (lead) position of a consist unless the locomotive has the capability of: (1) Controlling the dynamic braking effort in trailing locomotives in the consist that are so equipped; and (2) Displaying to the locomotive...

2010-10-01

232

Perforated Brake Efficiency Measurements Using a 20-mm Cannon.  

National Technical Information Service (NTIS)

Over the past few years, several field experiments have been performed using 105-mm and 120-mm cannons having perforated muzzle brakes. Significant differences in impulse reduction and gasdynamic efficiency have been reported in tests using the same 105-m...

G. C. Carofano

1993-01-01

233

Tau as a potential control variable for visually guided braking.  

PubMed

D. N. Lee (1976) described a braking strategy based on optical expansion in which the driver brakes so that the target's time-to-contact declines around a constant slope in the range -0.5 < or = tau < 0. The present results from a series of braking simulations confirm and extend earlier reports (E. H. Yilmaz & W. H. Warren, 1995) that performance is broadly compatible with the tau hypothesis. However, performance was not enhanced in situations that favored the estimation of tau, and unlike in earlier reports, performance deteriorated in the absence of a ground plane that provided information about speed and target distance. This finding suggests that the tau hypothesis does not provide a complete account of braking control. PMID:16634669

Rock, Paul B; Harris, Mike G

2006-04-01

234

Improved Service Life of Urban Transit Coach Brakes.  

National Technical Information Service (NTIS)

The program was concerned with finding the causes and evaluating pragmatic solutions for observed instances of reduced brake lining wear life in newly designed Advanced Design Buses (ADB). Based on a survey of six transit authorities, ADB's exhibited an a...

A. T. Hopper J. Hoess S. A. Barber

1986-01-01

235

6. DETAIL OF THE BRAKE SHOE ON THE EAST DRUM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. DETAIL OF THE BRAKE SHOE ON THE EAST DRUM AT THE STEWARD MINE, LOOKING EAST. THE EAST DRUM WAS UNDER SHOT, THE WEST OVERSHOT - Butte Mineyards, Stewart Mine, Intersection of Main & Woolman Streets, Butte, Silver Bow County, MT

236

Evaluation of Materials and Design Modifications for Aircraft Brakes.  

National Technical Information Service (NTIS)

A test program is described which was carried out to evaluate several proposed design modifications and several high-temperature friction materials for use in aircraft disk brakes. The evaluation program was carried out on a specially built test apparatus...

F. E. Kennedy M. B. Peterson T. L. Ho

1975-01-01

237

Rendezvous Terminal Phase Automatic Braking Sequencing and Targeting.  

National Technical Information Service (NTIS)

The purpose of the rendezvous terminal phase braking program is to provide the means of automatically bringing the primary orbiter within desired station keeping boundaries relative to the target satellite. A detailed discussion is presented on the brakin...

P. M. Kachmar

1973-01-01

238

49 CFR 393.55 - Antilock brake systems.  

Code of Federal Regulations, 2011 CFR

...CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR... (d) ABS malfunction circuits and signals for air braked...equipped with an electrical circuit that is capable of signaling...equipped with an electrical circuit that is capable of...

2011-10-01

239

49 CFR 393.42 - Brakes required on all wheels.  

Code of Federal Regulations, 2011 CFR

...co-driver. (6) Loaded housemoving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and similar motor vehicles are not required to be equipped with brakes, provided the speed at which the combination...

2011-10-01

240

17. LOWER OIL ROOM DIABLO POWERHOUSE: BRAKE AIR TANKS AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. LOWER OIL ROOM DIABLO POWERHOUSE: BRAKE AIR TANKS AND VERTICAL AIR COMPRESSORS, 1989. - Skagit Power Development, Diablo Powerhouse, On Skagit River, 6.1 miles upstream from Newhalem, Newhalem, Whatcom County, WA

241

Metals associated with stormwater-relevant brake and tire samples  

PubMed Central

Properly apportioning the loads of metals in highway stormwater runoff to the appropriate sources requires accurate data on source composition, especially regarding constituents that help to distinguish among sources. Representative tire and brake samples were collected from privately owned vehicles and aqueous extracts were analyzed for twenty-eight elements. Correlation principal components analysis (PCA) revealed that tires were most influenced by Zn, Pb, and Cu, while brakes were best characterized by Na and Fe followed by Ba, Cu, Mg, Mn, and K; the latter three may be due to roadside soil contributions. Notably elevated Cd contributions were found in several brake samples. A targeted Cd-plated brake rotor was sampled, producing results consistent with the elevated levels found in the larger sample population. This enriched source of Cd is of particular concern due to high toxicity of Cd in aquatic ecosystems.

McKenzie, Erica R.; Money, Jon E.; Green, Peter G.; Young, Thomas M.

2009-01-01

242

49 CFR 393.44 - Front brake lines, protection.  

Code of Federal Regulations, 2012 CFR

...apply the brakes may be located forward of the driver's seat as long as it can be operated manually by the driver when the driver is properly restrained by any seat belt assembly provided for use. Every bus shall meet...

2012-10-01

243

49 CFR 393.44 - Front brake lines, protection.  

Code of Federal Regulations, 2011 CFR

...apply the brakes may be located forward of the driver's seat as long as it can be operated manually by the driver when the driver is properly restrained by any seat belt assembly provided for use. Every bus shall meet...

2011-10-01

244

Silicone Brake Fluids: One-Year Field Test.  

National Technical Information Service (NTIS)

A study is being conducted to evaluate the performance of silicone brake fluids in military vehicles operating under various climatic conditions. These fluids are being field tested in vehicles operating at the Tropic Test Center (TTC), Panama Canal Zone;...

J. H. Conley R. Jamison C. B. Jordan

1975-01-01

245

Differential Braking for Limited-Authority Lateral Maneuvering.  

National Technical Information Service (NTIS)

This IDEA project designed a differential (side-to-side) braking system for limited authority lateral maneuvering that can support active ITS vehicle control systems aimed at preventing unintended road departure events. The vehicle is steered left or righ...

C. C. MacAdam R. D. Erin

2000-01-01

246

16 CFR 1512.5 - Requirements for braking system.  

Code of Federal Regulations, 2010 CFR

...in § 1512.18(d)(2)(vi). (2) Hand lever access. Hand lever mechanisms shall be located on the handlebars in...maximum outside dimension between the brake hand lever and the handlebars in the plane containing the...

2010-01-01

247

16 CFR 1512.5 - Requirements for braking system.  

Code of Federal Regulations, 2010 CFR

...in § 1512.18(d)(2)(vi). (2) Hand lever access. Hand lever mechanisms shall be located on the handlebars in...maximum outside dimension between the brake hand lever and the handlebars in the plane containing the...

2009-01-01

248

49 CFR 570.58 - Electric brake system.  

Code of Federal Regulations, 2011 CFR

...wiring shall not be frayed. Wiring clips or brackets shall not be broken or missing. Terminal connections shall be clean. Conductor wire gauge shall not be below the brake manufacturer's minimum recommendation. (1) Inspection procedure....

2011-10-01

249

49 CFR 393.42 - Brakes required on all wheels.  

Code of Federal Regulations, 2012 CFR

...co-driver. (6) Loaded housemoving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and similar motor vehicles are not required to be equipped with brakes, provided the speed at which the combination...

2012-10-01

250

ElectroMechanical Friction Disc, Ring and Drum Brakes  

Microsoft Academic Search

\\u000a In an E-M BBW AWB conversion mechatronic control system, electronic control units (ECU) and electrical wiring replace fluidical lines and equipment and E-M actuators replace fluidic pistons. When the driver\\u000a steps on the brake foot pedal, a computer sends information to a control box, which converts the electrical signals into an\\u000a electrical command: the E-M actuators on the brake disc,

B. T. Fijalkowski

251

Wear mechanisms of the C\\/SiC brake materials  

Microsoft Academic Search

The C\\/SiC brake materials were fabricated by chemical vapor infiltration combined with liquid melt infiltration. The wear mechanisms of C\\/SiC brake materials were investigated. The main wear mechanisms were grain-abrasion, oxidation-abrasion, fatigue wear, and adhesive wear. These wear mechanisms always occurred simultaneously , and showed mutual enhancing effects between them. Grain-abrasion mainly was the result of hard SiC grain action.

Shangwu Fan; Litong Zhang; Laifei Cheng; Jianxin Zhang; Shangjie Yang; Heyi Liu

2011-01-01

252

Driver sensitivity to brake pulse duration and magnitude  

Microsoft Academic Search

Adaptive cruise control (ACC) requires that the driver intervene in situations that exceed the capability of ACC. A brake pulse might provide a particularly compatible means of alerting the driver to situations in which the acceleration authority of the ACC has been exceeded. This study examined the sensitivity of the driver to brake pulses of five different amplitudes (0.01–0.025 g) and

J. D. Lee; D. V. Mcgehee; T. L. Brown; J. Nakamoto

2007-01-01

253

Nonlocal extremum seeking control for active braking control systems  

Microsoft Academic Search

A non-local extremum seeking control approach for active braking control systems is proposed. The typical design objective in electronic Anti-lock Braking Systems is to regulate the wheel slip as close as possible to the peak of the friction curve in any road condition. Accordingly, this control problem naturally fits the extremum seeking framework, as the output-to-reference map exhibits a global

Mara Tanelli; Alessandro Astolfi; Sergio M. Savaresi

2006-01-01

254

Brake Induced Vibration in Mountain Bikes (P112)  

Microsoft Academic Search

Mountain biking design continues to evolve towards more sophisticated systems including frame structures, suspension strategies,\\u000a and braking components. Frames become lighter with directionally designed stiffness. Suspensions are designed and tuned to\\u000a respond to diverse riding scenarios including large and small bump compliance, high and low speed compression and rebound\\u000a damping, and pedal feedback\\/suspension bob. Braking components are getting more powerful,

Robin C. Redfield

255

Gain-scheduled wheel slip control in automotive brake systems  

Microsoft Academic Search

A wheel slip controller is developed and experimentally tested in a car equipped with electromechanical brake actuators and a brake-by-wire system. A gain scheduling approach is taken, where the vehicle speed is viewed as a slowly time-varying parameter and the model is linearized about the nominal wheel slip. Gain matrices for the different operating conditions are designed using an LQR

Tor A. Johansen; Idar Petersen; Jens Kalkkuhl; Jens Ludemann

2003-01-01

256

A Road Test Comparison of Reaction Times Using an Operational Combined Brake-Accelerator Pedal and the Conventional Brake Pedal.  

National Technical Information Service (NTIS)

The experiment was conducted to compare road test reaction times obtained from a dual-function pedal that was completely integrated into an automobile's accelerating and braking systems. The resultant mean reaction times, measured from seventeen subjects ...

H. W. Higginbotham J. A. Frost

1972-01-01

257

Intelligently Controllable Walker with Magnetorheological Fluid Brake  

NASA Astrophysics Data System (ADS)

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.

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

258

Calibrating hydraulic network models  

Microsoft Academic Search

Although calibration should always be included in any hydraulic analysis, it is often neglected or done haphazardly. As a result, inappropriate data may be used or data errors may be overlooked, so the resulting hydraulic model is of limited value. The novice may see calibrating a hydraulic network model as a task as daunting as climbing Mt. Everest. This article

Lindell E. Ormsbee; Srinivasa Lingireddy

1997-01-01

259

An analysis of the annual probability of failure of the waste hoist brake system at the Waste Isolation Pilot Plant (WIPP)  

SciTech Connect

The Environmental Evaluation Group (EEG) previously analyzed the probability of a catastrophic accident in the waste hoist of the Waste Isolation Pilot Plant (WIPP) and published the results in Greenfield (1990; EEG-44) and Greenfield and Sargent (1993; EEG-53). The most significant safety element in the waste hoist is the hydraulic brake system, whose possible failure was identified in these studies as the most important contributor in accident scenarios. Westinghouse Electric Corporation, Waste Isolation Division has calculated the probability of an accident involving the brake system based on studies utilizing extensive fault tree analyses. This analysis conducted for the U.S. Department of Energy (DOE) used point estimates to describe the probability of failure and includes failure rates for the various components comprising the brake system. An additional controlling factor in the DOE calculations is the mode of operation of the brake system. This factor enters for the following reason. The basic failure rate per annum of any individual element is called the Event Probability (EP), and is expressed as the probability of failure per annum. The EP in turn is the product of two factors. One is the {open_quotes}reported{close_quotes} failure rate, usually expressed as the probability of failure per hour and the other is the expected number of hours that the element is in use, called the {open_quotes}mission time{close_quotes}. In many instances the {open_quotes}mission time{close_quotes} will be the number of operating hours of the brake system per annum. However since the operation of the waste hoist system includes regular {open_quotes}reoperational check{close_quotes} tests, the {open_quotes}mission time{close_quotes} for standby components is reduced in accordance with the specifics of the operational time table.

Greenfield, M.A. [Univ. of California, Los Angeles, CA (United States); Sargent, T.J.

1995-11-01

260

Thermophysical Properties of Automotive Metallic Brake Disk Materials  

NASA Astrophysics Data System (ADS)

The temperature distribution, the thermal deformation, and the thermal stress of automotive brake disks have quite close relations with car safety; therefore, much research in this field has been performed. However, successful and satisfactory results have not been obtained because the temperature-dependent thermophysical properties of brake disk materials are not sufficiently known. In this study, the thermophysical properties (thermal diffusivity, the specific heat, and the coefficient of thermal expansion) of three kinds of iron alloy series brake disk materials, FC250, FC170, and FCD50, and two kinds of aluminum alloy series brake disk materials, Al MMC and A356, were measured in the temperature range from room temperature to 500 °C, and the thermal conductivity was calculated using the measured thermal diffusivity, specific heat capacity, and density. As expected, the results show that the two series have significant differences in respect of the thermophysical properties, and to reduce the thermal deformation of the brake disk, the aluminum alloys with a high thermal conductivity and the iron alloys with low thermal expansion are recommended.

Kim, S. W.; Park, K.; Lee, S. H.; Kang, K. H.; Lim, K. T.

2008-12-01

261

Investigation of the Effects of Braking System Configurations on Thermal Input to Commuter Car Wheels.  

National Technical Information Service (NTIS)

A heat transfer model, previously developed to estimate wheel rim temperatures during tread braking of MU power cars and validated by comparison with operational test results, is extended and applied to cases involving several different blended brake syst...

J. E. Gordon O. Orringer

1996-01-01

262

A Simple Method for Predicting Muzzle Brake Effectiveness and Baffle-Surface Pressure.  

National Technical Information Service (NTIS)

The objective of this work is to produce a simple method for calculating load distributions on muzzle brake baffles during the firing process. With the load distribution known, the muzzle-brake effectiveness expression can be obtained and easily evaluated...

K. S. Fansler

1981-01-01

263

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

Code of Federal Regulations, 2012 CFR

...time. (1) Vehicle speed. (2) Brake pedal force. (3) Angular velocity at each wheel. ...differentiation of the vehicle speed. (h) Speed channel...time: (1) Vehicle speed. (2) Brake pedal force. (3) Angular velocity at each wheel....

2012-10-01

264

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

Code of Federal Regulations, 2011 CFR

...time. (1) Vehicle speed. (2) Brake pedal force. (3) Angular velocity at each wheel. ...differentiation of the vehicle speed. (h) Speed channel...time: (1) Vehicle speed. (2) Brake pedal force. (3) Angular velocity at each wheel....

2011-10-01

265

Bus, Truck, Tractor-Trailer Braking System Performance. Volume 2-Appendices and References.  

National Technical Information Service (NTIS)

The volume is comprised of the following appendicies: Test vehicles--data and specifications; Test procedures and instrumentation; Tire-road interface tests; Truck and tractor-trailer braking performance model; Braking performance diagram calculation prog...

R. W. Murphy R. Limpert L. Segel

1971-01-01

266

Bus, Truck, Tractor-Trailer Braking System Performance. Volume 1: Research Findings.  

National Technical Information Service (NTIS)

The objectives of the study were to determine the range of braking performance currently exhibited by buses, trucks, and tractor-trailers and to establish the maximum braking performance capabilities of these vehicles based upon full utilization of the te...

R. W. Murphy R. Limpert L. Segel

1971-01-01

267

Hydraulic Brake Hose Test Fmvss 106 Manufactured by Wagner-Lockheed.  

National Technical Information Service (NTIS)

The report pertains to tests conducted by an independent contractor as part of the National Highway Safety Bureau compliance testing program to determine whether or not motor vehicles and items of motor vehicle equipment comply with applicable Federal Mot...

1969-01-01

268

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

Code of Federal Regulations, 2011 CFR

...disengaged) when the vehicle speed decreases to 20 mph. S6.5Engine. Engine idle speed and ignition timing settings...with an adjustable engine speed governor, it is adjusted...and 100 °F. S6.8Wind velocity. The wind velocity...

2011-10-01

269

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

Code of Federal Regulations, 2012 CFR

...disengaged) when the vehicle speed decreases to 20 mph. S6.5Engine. Engine idle speed and ignition timing settings...with an adjustable engine speed governor, it is adjusted...and 100 °F. S6.8Wind velocity. The wind velocity...

2012-10-01

270

Regenerative braking device with rotationally mounted energy storage means  

DOEpatents

A regenerative braking device for an automotive vehicle includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (30) and an output shaft (32), clutches (50, 56) and brakes (52, 58) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. In a second embodiment the clutches and brakes are dispensed with and the variable ratio transmission is connected directly across the input and output shafts. In both embodiments the rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft rotates faster or relative to the output shaft and are torsionally relaxed to deliver energy to the vehicle when the output shaft rotates faster or relative to the input shaft.

Hoppie, Lyle O. (Birmingham, MI)

1982-03-16

271

Measurement of the disc-pad friction coefficient for mechanical brakes using direct and indirect methods  

Microsoft Academic Search

It is necessary to guarantee the proper brake force to stop a train safely in a limited distance and o adjust its speed. Currently,\\u000a most trains are run by electrical power and have a combined electrical and mechanical (friction) braking system. The mechanical\\u000a brake force is determined by many parameters, such as the friction coefficient of the brake disc and

Y.-G. Kim; S.-W. Kim; C.-K. Park; T.-W. Park; Y.-M. Kim

2011-01-01

272

Study on Reliability Test for Brake Control Execution Unit of Rail Transit Vehicle  

Microsoft Academic Search

The brake system is the safety-critical subsystem of rail transit vehicle. However, the reliability test technology related to rail transportation equipments is much needed in China. In this paper, a certain Chinese computer-controlled electro-pneumatic brake system was selected to conduct reliability analysis by FMEA and BCEU (Brake Control Execution Unit) was determined the weak link of the brake system. Then,

Luo Min; Wu Meng-lin; Wang Xiao-yan

2010-01-01

273

Real-Time Dynamic Brake Assessment Proof of Concept Final Report  

Microsoft Academic Search

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

Mary Beth Lascurain; Oscar Franzese; Gary J Capps

2011-01-01

274

Periodic brake orbits in the planar isosceles three-body problem  

NASA Astrophysics Data System (ADS)

A brake orbit is an orbit that starts with zero initial velocity. The purpose of this paper is to find periodic brake orbits in the isosceles three-body problem. We use various shooting arguments; we follow a curve of brake initial conditions under the flow until it reaches a suitable surface, and show that the image curve includes a point that corresponds to a periodic orbit. As a result, we prove the existence of six types of periodic brake orbits.

Chen, Nai-Chia

2013-10-01

275

Three-dimensional simulation of muzzle brake flowfields  

NASA Astrophysics Data System (ADS)

A three-dimensional numerical inviscid model of the time-dependent near field of multi-element muzzle brakes has been developed. The model includes the effect of the free air blast, the exhaust of the barrel air ahead of the shell, shell ejection and flight, and the exhausting of the propellant gases. Detailed calculations of this flow sequence are compared with pressure measurements on the frontal surfaces and top plate of a 20 mm cannon double baffle muzzle brake tested by Gion and Faller. Relative agreement between the calculated and measured peak overpressure on these surfaces is shown.

Buell, J. C.; Widhopf, G. F.

1984-06-01

276

Transient analysis of thermoelastic contact problem of disk brakes  

NASA Astrophysics Data System (ADS)

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 established and the Von Mises stresses in the disk, the contact pressure distribution in pads. The results are satisfactory compared to those found in the literature.

Belhocine, Ali; Bouchetara, Mostefa

2013-06-01

277

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

Code of Federal Regulations, 2010 CFR

...designed to contain compressed air or brake fluid (excluding failure of a component of...determined in S5.6.3.4, and all air and fluid pressures in the vehicle's braking systems...designed to contain compressed air or brake fluid (consistent with the parenthetical...

2009-10-01

278

Research of Speed Model and Simulation Based on Vehicle Braking Tyre Imprint  

Microsoft Academic Search

For accurately calculating the former speed of vehicle braking, by analyzing the vehicle wheels braking-forces, and considering the changing position of gravity center and the speed changing of braking-force during time increasing, constructing the vehicle speed calculating models which is based on tyre imprint. Considering the variety types of tyre printing on accident site and the requirements for quickly and

Wang Shuda; Xiao Jingyang; Han Xuena

2009-01-01

279

The Cooling Device of Drum Brake System by Using Thermoelestic Cooling Module  

Microsoft Academic Search

The research is presented a kind of cooling device for a vehicleˇ¦s drum brake cooling system, which comprises a thermoelectric cooling (TEC) chip and a heat exchange system. After inputting electric power, the TEC chip provides one cooling surface which is stick on the brake system and absorbs the heat from the brake pads or shoes. The other surface releases

M.-H. Hsueh

2012-01-01

280

TEMPERATURE AND THERMAL STRESSES IN A BRAKE DRUM SUBJECTED TO CYCLIC HEATING  

Microsoft Academic Search

For the optimized design of a brake drum, it appears to be very important to examine the transient temperature and thermal stress distributions in the brake drum. In the direct measurement, of them, however, a number of difficulties are involved In this study, in order to examine the initiation mechanism of the thermal crack in the brake drum, the temperature

Khairul Fuad; M. Daimaruya; H. Kobayashi

1994-01-01

281

A study on the friction characteristics and durability of band brakes  

Microsoft Academic Search

A band brake is often used as a braking device in an automatic transmission because it fits around the clutch drum and does not require additional space. Its friction characteristics vary depending on the oil film between the brake band and the drum. Less friction force occurs under lower pressure and greater lubrication. In this study, the relationship between friction

Yasushi Mori; Yoshiaki Kato; Ryoukou Akasaka

1995-01-01

282

Numerical simulation and analysis for transient thermal field of a drum brake based on the test  

Microsoft Academic Search

Three-dimensional finite element model of a drum brake is built in this paper. According to test conditions of brake heat fade and other relevant national standards, using ANSYS Workbench, brake drum thermal field is simulated and studied. Through several simulation methods revised about initial conditions, to achieve fitting of the simulation curve and test curve. The boundary conditions for temperature

Ma Xun; Zhang Jiwei

2010-01-01

283

The onset of squeal vibrations in drum brake systems resulting from a coupled mode instability  

Microsoft Academic Search

In the last two decades there has been a great deal of research done to model, predict and understand brake squeal in both disc and drum brakes. The goal of this study was to build a sufficiently accurate analytical model that can be used to predict brake squeal and to gain a better understanding of some of the mechanisms responsible

Brian Kent Servis

2000-01-01

284

Frictional behavior of automotive brake materials under wet and dry conditions  

Microsoft Academic Search

The purpose of this effort was to develop an improved understanding of the relationship between the structure and frictional behavior of materials in the disc brake\\/rotor interface with a view toward improving the performance of automotive disc brakes. The three tasks involved in this Cooperative Research and Development Agreement (CRADA) were as follows: Task 1. Investigation of Brake Pads and

P. J. Blau; R. L. Martin; M. H. Weintraub; Ho Jang; W. Donlon

1996-01-01

285

49 CFR 232.103 - General requirements for all train brake systems.  

Code of Federal Regulations, 2010 CFR

...pressure. (k) The maximum brake pipe pressure shall not be greater...Performance Specification for Freight Brakes,â contained in the AAR Manual...on the availability of this material at NARA, call 202-741-6030...C of this part experiences a brake pipe air flow of greater...

2010-10-01

286

Wear mechanism in automotive brake materials, wear debris and its potential environmental impact  

Microsoft Academic Search

A model semi-metallic brake lining was subjected to full-scale automotive brake dynamometer tests. The structural properties and surface topography of brake linings were analyzed at different stages of wear testing and correlated to frictional performance. Characteristics of released wear particles were also addressed. A combination of abrasive and adhesive wear with oxidative processes dominated the friction process. Formation of a

J. Kukutschová; V. Roubí?ek; K. Malachová; Z. Pavlí?ková; R. Holuša; J. Kuba?ková; V. Mi?ka; D. MacCrimmon; P. Filip

2009-01-01

287

49 CFR 232.103 - General requirements for all train brake systems.  

Code of Federal Regulations, 2010 CFR

...pressure. (k) The maximum brake pipe pressure shall not be greater...Performance Specification for Freight Brakes,â contained in the AAR Manual...on the availability of this material at NARA, call 202-741-6030...C of this part experiences a brake pipe air flow of greater...

2009-10-01

288

A Cost-Effective Method of Electric Brake With Energy Regeneration for Electric Vehicles  

Microsoft Academic Search

This paper proposes a simple but effective method of electric brake with energy regeneration for a brushless DC motor of an electric vehicle (EV). During the braking period, the proposed method only changes the switching sequence of the inverter to control the inverse torque so that the braking energy will return to the battery. Compared with the presented methods, the

Ming-Ji Yang; Hong-Lin Jhou; Bin-Yen Ma; Kuo-Kai Shyu

2009-01-01

289

Airborne asbestos concentration from brake changing does not exceed permissible exposure limit  

Microsoft Academic Search

The use in the past, and to a lesser extent today, of chrysotile asbestos in automobile brake systems causes health concerns among professional mechanics. Therefore, we conducted four separate tests in order to evaluate an auto mechanic’s exposure to airborne asbestos fibers while performing routine brake maintenance. Four nearly identical automobiles from 1960s having four wheel drum brakes were used.

Charles L. Blake; Drew R. Van Orden; Marek Banasik; Raymond D. Harbison

2003-01-01

290

Application of Adaptive Sliding Mode Control for Regenerative Braking Torque Control  

Microsoft Academic Search

In air hybrid vehicles, there are two independent braking systems: frictional and regenerative. Since the regenerative braking torque is proportional to the parameters such as tank pressure and engine speed, a controller is needed for the control of the regenerative braking torque generated by internal combustion engine, based on the driver preference. In this work, a nonlinear control approach based

Amir Fazeli; Meysar Zeinali; Amir Khajepour

2012-01-01

291

Compact MR-brake with serpentine flux path for haptics applications  

Microsoft Academic Search

This research explores a new approach to shape the magnetic flux path in a MR brake. Magnetically conductive and non-conductive elements were stacked to weave the magnetic flux through the rotor and the outer shell of the brake. This approach enabled design of a more compact and powerful MR brake. In addition, a ferro-fluidic sealing technique was developed to prevent

Doruk Senkal; Hakan Gurocak

2009-01-01

292

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

Code of Federal Regulations, 2010 CFR

...a parking brake of a friction type with a solely mechanical...and so that disc brake friction lining thickness may...without removing the pads. S5.2Service brake...linings from the shoes or pad, detachment or fracture...stops are made with the clutch disengaged....

2009-10-01

293

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

Code of Federal Regulations, 2010 CFR

...a parking brake of a friction type with a solely mechanical...and so that disc brake friction lining thickness may...without removing the pads. S5.2Service brake...linings from the shoes or pad, detachment or fracture...stops are made with the clutch disengaged....

2010-10-01

294

Evaluation of a sudden brake warning system: Effect on the response time of the following driver  

Microsoft Academic Search

This study used a video-based braking simulation dual task to carry out a preliminary evaluation of the effect of a sudden brake warning system (SBWS) in a leading passenger vehicle on the response time of the following driver. The primary task required the participants (N=25, 16 females, full NZ license holders) to respond to sudden braking manoeuvres of a lead

Robert B. Isler; Nicola J. Starkey

2010-01-01

295

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

Code of Federal Regulations, 2010 CFR

...freight cars equipped with stand-alone ECP brake systems unless: (1) The...that are equipped with stand-alone ECP brake systems provided all of the following...freight cars equipped with stand-alone ECP brake systems; and (3) The...

2009-10-01

296

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

Code of Federal Regulations, 2010 CFR

...freight cars equipped with stand-alone ECP brake systems unless: (1) The...that are equipped with stand-alone ECP brake systems provided all of the following...freight cars equipped with stand-alone ECP brake systems; and (3) The...

2010-10-01

297

Effect of cellular telephone conversations and other potential interference on reaction time in a braking response  

Microsoft Academic Search

This experiment studied the effect of phone conversations and other potential interference on reaction time (RT) in a braking response. Using a laboratory station which simulated the foot activity in driving, 22 research participants were requested to release the accelerator pedal and depress the brake pedal as quickly as possible following the activation of a red brake lamp. Mean reaction

William Consiglio; Peter Driscoll; Matthew Witte; William P. Berg

2003-01-01

298

Hydraulic fracture design optimization  

SciTech Connect

This research and development investigation, sponsored by US DOE and the oil and gas industry, extends previously developed hydraulic fracture geometry models and applied energy related characteristic time concepts towards the optimal design and control of hydraulic fracture geometries. The primary objective of this program is to develop rational criteria, by examining the associated energy rate components during the hydraulic fracture evolution, for the formulation of stimulation treatment design along with real-time fracture configuration interpretation and control.

Lee, Tae-Soo; Advani, S.H.

1992-01-01

299

Hydraulic fracture design optimization  

SciTech Connect

This research and development investigation, sponsored by US DOE and the oil and gas industry, extends previously developed hydraulic fracture geometry models and applied energy related characteristic time concepts towards the optimal design and control of hydraulic fracture geometries. The primary objective of this program is to develop rational criteria, by examining the associated energy rate components during the hydraulic fracture evolution, for the formulation of stimulation treatment design along with real-time fracture configuration interpretation and control.

Lee, Tae-Soo; Advani, S.H.

1992-06-01

300

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

NASA Astrophysics Data System (ADS)

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

Retzer, H.; Mishra, R.; Ball, A.; Schmidt, K.

2012-05-01

301

A Laboratory Activity on the Eddy Current Brake  

ERIC Educational Resources Information Center

|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…

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

2012-01-01

302

Neutron star dynamics, braking indices and energy dissipation  

NASA Astrophysics Data System (ADS)

Models of pulsar glitches and postglich relaxation are reviewed. Implications for braking indices due to internal torques in the neutron star, and energy dissipation by internal torques are discussed. All recent observations of pulsars with large (Vela pulsar like) glitches and second derivatives are seen to fit with the same glitch dynamics that the Vela pulsar exhibits.

Alpar, M. A.

303

Study of Braking Operations Using a Locomotive Simulator.  

National Technical Information Service (NTIS)

The Volpe Center is currently supporting the Federal Railroad Administration in developing revisions to the safety standards for train air brakes. As part of the program, one of the tasks was to evaluate the effects certain operating parameters have on th...

Y. H. Tang

1994-01-01

304

Driver Behavior and Situation Aware Brake Assistance for Intelligent Vehicles  

Microsoft Academic Search

This paper deals with the development of Human-Centric Intelligent Driver Assistance Systems. Rear-end collisions account for a large portion of traffic accidents. To help mitigate this problem, predictive braking systems and adaptive cruise control systems have been developed. However, these types of systems usually rely solely on the vehicle and vehicle surround sensors, either ignoring the human component of driving

Joel C. McCall; Mohan M. Trivedi

2007-01-01

305

Oxygen-Diffused Titanium as a Candidate Brake Rotor Material  

SciTech Connect

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.

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

2009-01-01

306

The unbalanced signal measuring of automotive brake drum  

Microsoft Academic Search

For the purpose of the research and development of automatic balancing system by mass removing, the dissertation deals with the measuring method of the unbalance signal, the design the automatic balance equipment and the software. This paper emphases the testing system of the balancer of automotive brake drum. The paper designs the band-pass filter product with favorable automatic follow of

Xiao-Dong Wang; Sheng-Hua Ye; Bang-Cheng Zhang

2005-01-01

307

Brakes Specialist. Teacher Edition. Automotive Service Series. Second Edition.  

ERIC Educational Resources Information Center

|This curriculum guide for automatic brakes service is one in a series of automotive service speciality publications that is based on the National Institute of Automotive Service Excellence task lists. The curriculum is composed of four units. Each unit of instruction may contain some or all of the following components: objective sheet, suggested…

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

308

TRANSIENT ANALYSIS OF THERMOELASTIC CONTACT BEHAVIORS IN COMPOSITE MULTIDISK BRAKES  

Microsoft Academic Search

The transient analyses of the thermoelastic contact problem are performed for carbon–carbon composite multidisk brakes subject to mechanical and frictionally excited thermal loads. The finite element method, based on the coupled theory in which displacement and temperature fields are mutually affected, is applied for the numerical simulations. In the present study, to improve the accuracy of computations and stabilize the

Ji-Hoon Choi; Jae-Hung Han; In Lee

2004-01-01

309

Long term high energy clutch\\/braking technique  

Microsoft Academic Search

A wet clutching\\/braking mechanism has been designed to operate as prescribed in a patent issued to R.A. Iverson in 1982. A key element in this design is to allow high radial oil flow rates through the clutch plate stack to carry the heat generated during power absorption away from the clutch disks. A continuously variable transmission incorporating this new clutch

D. A. Renfroe; R. A. Iverson

1986-01-01

310

Magnetic braking revisited: an activity for How science works  

NASA Astrophysics Data System (ADS)

The National Curriculum for 14-16 year old students in England contains a mandatory element called How science works. Included in this material is interpretation of data, collecting data from primary sources, using ICT tools, and developing an argument and drawing conclusions. What follows is an activity, based on magnetic braking, which allows students to develop these areas and more.

Ireson, Gren; Twidle, John

2008-09-01

311

Performance and evaluation of eco-friendly brake friction materials  

Microsoft Academic Search

Eco-friendly brake friction materials were formulated without copper, lead, tin, antimony trisulfide, and whisker materials, to minimize their potential negative environmental impacts. A combination of scanning electron microscopy with energy dispersive microanalysis, profilometry, and thermogravimetry allows successful analysis of friction surface and thermal stability of friction materials. Extension evaluation method was applied to rank the friction materials using multi-parameter criteria,

Rongping Yun; Peter Filip; Yafei Lu

2010-01-01

312

Electromagnetic brake for a camshaft phase change device  

SciTech Connect

This patent describes a phase change device. It comprises a first shaft; an input member supported for rotation on the first shaft; an output member fixed to the first shaft; advancing means interconnecting the input and output members, the advancing means being operative upon axial movement to effect limited relative rotation between the input and output members; drum means supported for rotation on the first shaft and engaged with the advancing means to effect the axial movement of the advancing means when a retarding force is applied to the drum means; and actuating means operable to apply the retarding force; the improvement wherein the actuating means comprises an electromagnetic brake assembly, the electromagnetic brake assembly comprising an annular housing defining pole pieces of the electromagnet, a magnetic coil received in the housing, a nonmagnetic plate member enclosing the housing, friction material adhered to the plate member, a brake disc surface formed on the drum, and means for mounting the housing on the first shaft in juxtaposition with the brake disc surface in a substantially fixed angular position while permitting limited axial movement relative to the disc surface.

Muir, D.J.; Brune, J.E.; Van Deusen, B.K.; Day, J.K.

1991-07-16

313

Fuzzy Logic Based Automatic Braking System in Trains  

Microsoft Academic Search

This paper focuses a new way of approach to find the solution for the artificial intelligent braking system in train using the fuzzy logic controller. Here we are designing the fuzzy logic controller using fuzzy logic tool box in mat lab software. The main function of the fuzzy logic controller used here is to automatically stop the train in each

G. Sankar; S. Saravana Kumar

2006-01-01

314

5. FLOOR 3; SHOWS BRAKE LEVER, BLOCK FORMERLY USED TO ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. FLOOR 3; SHOWS BRAKE LEVER, BLOCK FORMERLY USED TO RAISE IT AND HOOK WHICH KEPT IT IN THE 'OFF' POSITION; ALSO SEEN ARE THE LARGE BLOCKS SUSPENDED FROM THE CAP FRAME WHICH HOLD THE TRUCK WHEELS TO CENTER THE CAP - Hayground Windmill, Windmill Lane, East Hampton, Suffolk County, NY

315

22. INTERIOR OF BRIDGE TENDER'S HOUSE SHOWING CLUTCH AND BRAKE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. INTERIOR OF BRIDGE TENDER'S HOUSE SHOWING CLUTCH AND BRAKE HANDLES, AIR VALVE FOR RAIL LOCKS, AND MOTOR CONTROLLER FOR TURNING MACHINERY, LOOKING N. PHOTOGRAPHER: SARAH J. DENNETT & ROBERT A. RYAN - Keokuk & Hamilton Bridge, Spanning Mississippi River, Keokuk, Lee County, IA

316

An EAC Based Braking Resistor Approach for Transient Stability Improvement  

Microsoft Academic Search

In this paper, a new braking resistor approach using the equal area criterion (EAC) is presented to improve the transient stability of power systems. A conventional and a fuzzy logic controller have been developed and compared. The proposed approach was tested on a single machine system, and then on the IEEE WSCC multimachine test system. Simulation results indicate that the

Yuning Chen; M. E. El-Harway

2006-01-01

317

Bud development and hydraulics  

PubMed Central

The distal zone of one-year-old apple (Malus domestica) shoots was studied on five cultivars for bud size and composition (number of appendages) and hydraulic conductance before bud burst. Our hypothesis was that bud development was related to hydraulic conductance of the sap pathway to the bud independent of an acrotonic (proximal vs. distal) effect. Bud size and composition, and hydraulic conductance, were highly variable for all cultivars. A positive correlation was demonstrated between both the number of cataphylls and green-leaf primordia and hydraulic conductance. Cultivar and bud size affected the intercept of these relationships more than the slope suggesting similar scaling between these variables but different hydraulic efficiencies. A great proportion of small buds were also characterized by null values of hydraulic conductance. Our study suggests that hydraulically mediated competitions exist between adjacent buds within a same branching zone prefiguring the variability of lateral types in the following growing season. It is hypothesized that this developmental patterning is driven by hydraulic characteristics of the whole-metamer, including the subtending leaf, during bud development.

Cochard, Herve

2008-01-01

318

Hydraulics of pipelines  

Microsoft Academic Search

This text\\/reference addresses all hydraulic aspects of pipeline design. Incorporates many real-life examples from the author's experience in the design and operation of pipelines. Topics covered include basic equations necessary to pipeline design, how to conduct a feasibility study and perform economic analysis, design considerations for pumps and valves, how to suppress cavitation, hydraulic transients, trapped air, and methods of

Tullis

1989-01-01

319

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

NASA Astrophysics Data System (ADS)

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

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

2005-05-01

320

Downhole hydraulic seismic generator  

DOEpatents

A downhole hydraulic seismic generator system for transmitting energy wave vibrations into earth strata surrounding a borehole. The system contains an elongated, unitary housing operably connected to a well head aboveground by support and electrical cabling, and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a hydraulic oscillator containing a double-actuating piston whose movement is controlled by an electro-servovalve regulating a high pressure hydraulic fluid flow into and out of upper and lower chambers surrounding the piston. The spent hydraulic fluid from the hydraulic oscillator is stored and pumped back into the system to provide high pressure fluid for conducting another run at the same, or a different location within the borehole.

Gregory, Danny L. (Corrales, NM); Hardee, Harry C. (Albuquerque, NM); Smallwood, David O. (Albuquerque, NM)

1992-01-01

321

Downhole hydraulic seismic generator  

DOEpatents

A downhole hydraulic seismic generator system for transmitting energy wave vibrations into earth strata surrounding a borehole. The system contains an elongated, unitary housing operably connected to a well head aboveground by support and electrical cabling, and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a hydraulic oscillator containing a double-actuating piston whose movement is controlled by an electro-servovalve regulating a high pressure hydraulic fluid flow into and out of upper and lower chambers surrounding the piston. The spent hydraulic fluid from the hydraulic oscillator is stored and pumped back into the system to provide high pressure fluid for conducting another run at the same, or a different location within the borehole. 4 figs.

Gregory, D.L.; Hardee, H.C.; Smallwood, D.O.

1990-12-31

322

Downhole hydraulic seismic generator  

DOEpatents

A downhole hydraulic seismic generator system for transmitting energy wave vibrations into earth strata surrounding a borehole. The system contains an elongated, unitary housing operably connected to a well head aboveground by support and electrical cabling, and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a hydraulic oscillator containing a double-actuating piston whose movement is controlled by an electro-servovalve regulating a high pressure hydraulic fluid flow into and out of upper and lower chambers surrounding the piston. The spent hydraulic fluid from the hydraulic oscillator is stored and pumped back into the system to provide high pressure fluid for conducting another run at the same, or a different location within the borehole. 4 figs.

Gregory, D.L.; Hardee, H.C.; Smallwood, D.O.

1990-01-01

323

Guidelines for numerical vibration and acoustic analysis of disc brake squeal using simple models of brake systems  

NASA Astrophysics Data System (ADS)

Brake squeal has become of increasing concern to the automotive industry but guidelines on how to confidently predict squeal propensity are yet to be established. While it is standard practice to use the complex eigenvalue analysis to predict unstable vibration modes, there have been few attempts to calculate their acoustic radiation. Here guidelines are developed for numerical vibration and acoustic analysis of brake squeal using models of simplified brake systems with friction contact by considering (1) the selection of appropriate elements, contact and mesh; (2) the extraction of surface velocities via forced response; and (3) the calculation of the acoustic response itself. Results indicate that quadratic tetrahedral elements offer the best option for meshing more realistic geometry. A mesh has to be sufficiently fine especially in the contact region to predict mesh-independent unstable vibration modes. Regarding the vibration response, only the direct, steady-state method with a pressurised pad and finite sliding formulation (allowing contact separation) should be used. Comparison of different numerical methods suggest that a obroadband fast multi-pole boundary element method with the Burton-Miller formulation would efficiently solve the acoustic radiation of a full brake system. Results also suggest that a pad lift-off can amplify the acoustic radiation similar to a horn effect. A horn effect is also observed for chamfered pads which are used in practice to reduce the number and strength of unstable vibration modes. These results highlight the importance of optimising the pad shape to reduce acoustic radiation of unstable vibration modes.

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

2013-04-01

324

An evaluation of the historical exposures of mechanics to asbestos in brake dust.  

PubMed

This article presents a historical analysis of published data regarding the exposure of brake mechanics to asbestos as a result of doing brake work. Concerns about this possible hazard were first raised in the late 1960s. This analysis focuses on 30 years of data collected during the brake repair event (e.g., a brake job) and 8-hour time-weighted average (TWA) personal samples. A brake job TWA represents the average concentration a mechanic experienced during brake servicing, rather than throughout the workday, and an 8-hour TWA represents the average airborne concentration of asbestos for the entire workday (which would involve brake work and other activities). Nearly 200 brake job and 8-hour TWA airborne asbestos samples were analyzed to assess how asbestos concentrations varied by type of vehicle serviced, country in which mechanics worked, time period, and brake-cleaning method. To facilitate comparisons, brake job TWAs were converted to estimated 8-hour TWAs using the durations and number of brake jobs performed per mechanic each day. Estimated and measured 8-hour TWAs for mechanics servicing automobiles and light trucks ranged from <0.002 to 0.68 f/cc, with a mean of 0.04 f/cc. In contrast, the 8-hour TWAs for mechanics servicing heavy trucks and buses ranged from 0.002 to 1.75 f/cc, with a mean of 0.2 f/cc, suggesting that these mechanics experienced higher daily asbestos exposures than automobile and light truck mechanics. Brake job and 8-hour TWAs for brake mechanics worldwide were found to be similar during the same time periods, and they were consistently below contemporaneous occupational health standards in the United States. The increased use of brake-dust control measures in some garages resulted in at least a 10-fold decrease in the TWA airborne concentrations of asbestos from the 1970s to the late 1980s. PMID:12959890

Paustenbach, Dennis J; Richter, Richard O; Finley, Brent L; Sheehan, Patrick J

2003-10-01

325

Anti-lock brake system: an assessment of training on driver effectiveness.  

PubMed

When activated correctly, Anti-Lock Brake Systems (ABS) can provide drivers with the ability to stop a vehicle in shorter distances and allow for more vehicle control under heavy braking than conventional brake systems. This is especially true under wet or icy road conditions. However, it is believed that many drivers are either unaware of the correct method of activation or they revert back to the old method of pumping the brakes when they are faced with a hard braking situation. This paper examines the effectiveness of implementing low-cost training methods for alerting drivers to the correct brake activation technique. A 4-page, color training pamphlet was developed and subjects were given a short period of time to read it over before being asked to drive on an icy test track. Results indicated that those subjects who received the training were able to stop in shorter distances in a straight line braking event and more often used the correct brake activation technique than those subjects who did not receive the training. However, the stopping distance benefits were not realized in the curved and surprise braking events. These results suggest that the transfer of verbal knowledge may have value as a means for solving the apparent problem of improper ABS usage. However, some additional research should be done to validate these results. Since this experiment was conducted directly after the material was read, the possibility exists that without reinforcement, the trained braking techniques might become extinct in a short period of time. PMID:9110044

Mollenhauer, M A; Dingus, T A; Carney, C; Hankey, J M; Jahns, S

1997-01-01

326

Investigation of a Combined Slip Control Braking and Closed Loop Four Wheel Steering System for an Automobile During Combined Hard Braking and Severe Steering  

Microsoft Academic Search

Conventional anti-lock braking systems (ABS) permit automobiles to achieve short stopping distance with good directional control and stability during moderate manuevers. However, during emergency maneuvers where hard braking is combined with severe steering, normally stable (i.e., understanding) cars, even those equipped with ABS, can spin out due to a change to an unstable oversteer condition. In this work, a new

Saied Taheri; E. Harry Law

1990-01-01

327

IOSDL Seasoar Hydraulic Unit.  

National Technical Information Service (NTIS)

A series of static and dynamic laboratory measurements taken on five IOSDL (Institute of Oceanographic Sciences Deacon Laboratory) SeaSoar hydraulic units is reported. Their operation, the test equipment and the test methods used are described. Analysis o...

T. J. P. Gwilliam D. Grohmann R. F. Wallace

1992-01-01

328

Investigations of Hydraulic Turbines.  

National Technical Information Service (NTIS)

Contents: Effects of the initial degree of turbulence on the hydrodynamic coefficients of the blade systems of axial hydraulic turbines; Accuracy of determining the flow around straight blade cascades; Application of Stanitz and Prian's approximate theory...

G. A. Svinarev

1969-01-01

329

Hydraulic System Acoustical Diagnostics.  

National Technical Information Service (NTIS)

This project is a continuation of previous acoustics studies conducted to determine if the vibration signature of hydraulic components could provide information concerning the operational health of the system. The concept of using internally produced nois...

R. Inoue R. K. King

1980-01-01

330

Plasma Jet Braking: Energy Dissipation and Nonadiabatic Electrons  

SciTech Connect

We report in situ observations by the Cluster spacecraft of wave-particle interactions in a magnetic flux pileup region created by a magnetic reconnection outflow jet in Earth's magnetotail. Two distinct regions of wave activity are identified: lower-hybrid drift waves at the front edge and whistler-mode waves inside the pileup region. The whistler-mode waves are locally generated by the electron temperature anisotropy, and provide evidence for ongoing betatron energization caused by magnetic flux pileup. The whistler-mode waves cause fast pitch-angle scattering of electrons and isotropization of the electron distribution, thus making the flow braking process nonadiabatic. The waves strongly affect the electron dynamics and thus play an important role in the energy conversion chain during plasma jet braking.

Khotyaintsev, Yu. V.; Cully, C. M.; Vaivads, A.; Andre, M.; Owen, C. J. [Swedish Institute of Space Physics, Uppsala (Sweden); Mullard Space Science Laboratory, University College London, Dorking (United Kingdom)

2011-04-22

331

Hydraulic motor for cars  

SciTech Connect

A hydraulic motor for a car is described comprising, in combination, an automotive vehicle engine for travel self-propulsion, including a block, a plurality of cylinders in the block, a piston slidable in each cylinder, a crankshaft in the block, a piston rod connected between the crankshaft and each of the pistons, a power take-off gear on the crankshaft for the travel self-propulsion, and the engine including a hydraulic means for driving the pistons in the cylinders.

Gagnon, D.C.

1986-09-02

332

Three-dimensional simulation of muzzle brake flowfields  

Microsoft Academic Search

A three-dimensional numerical inviscid model of the time-dependent near field of multi-element muzzle brakes has been developed. The model includes the effect of the free air blast, the exhaust of the barrel air ahead of the shell, shell ejection and flight, and the exhausting of the propellant gases. Detailed calculations of this flow sequence are compared with pressure measurements on

J. C. Buell; G. F. Widhopf

1984-01-01

333

Energy Efficiency in Heavy Vehicle Tires, Drivetrains, and Braking Systems  

SciTech Connect

This document was prepared to support the primary goals of the Department of Energy, Office of Heavy Vehicle Technologies. These were recently stated as follows: ''Develop by 2004 the enabling technologies for a class 7-8 truck with a fuel efficiency of 10 mpg (at 65 mph) which will meet prevailing emission standards. For Class 3-6 trucks operating on an urban driving cycle, develop by 2004 commercially viable vehicles that achieve at least double the fuel economy of comparable current vehicles (1999), and as a research goal, reduce criteria pollutants to 30% below EPA standards. Develop by 2004 the diesel engine enabling technologies to support large-scale industry dieselization of Class 1 and 2 trucks, achieving a 35 % fuel efficiency improvement over comparable gasoline-fueled trucks, while meeting applicable emissions standards.'' The enabling technologies for improving the fuel efficiency of trucks, include not only engine technologies but also technologies involved with lowering the rolling resistance of tires, reducing vehicle aerodynamic drag, improving thermal management, and reducing parasitic frictional losses in drive train components. Opportunities also exist for making better use of the energy that might ordinarily be dissipated during vehicle braking. Braking systems must be included in this evaluation since safety in truck operations is vital, and braking requirements are greater for vehicles having lowered resistance to rolling. The Office of Heavy Vehicle Technologies has initiated a program to improve the aerodynamics of heavy vehicles through wind tunnel testing, computational modeling, and on-road evaluations. That activity is described in a separate multi-year plan; therefore, emphasis in this document will be on tires, drive trains, and braking systems. Recent, dramatic fluctuations in diesel fuel prices have emphasized the importance of effecting savings in truck fuel economy by implementing new component designs and materials.

Peter J. Blau

2000-04-26

334

Tribological properties of brake friction materials with steel fibers  

Microsoft Academic Search

The tribological properties of brake friction materials with and without steel fibers were investigated. The focus of this\\u000a study was determining the effect of steel fibers on the speed sensitivity of the friction coefficient. The speed sensitivity\\u000a of the friction coefficient is closely associated with the stick-slip phenomenon. The results indicate that the friction material\\u000a containing steel filbers was more

Sung Bin Park; Keun Hyung Cho; Sola Jung; Ho Jang

2009-01-01

335

Friction and wear behavior of carbon fiber reinforced brake materials  

Microsoft Academic Search

A new composite brake material was fabricated with metallic powders, barium sulphate and modified phenolic resin as the matrix\\u000a and carbon fiber as the reinforced material. The friction, wear and fade characteristics of this composite were determined\\u000a using a D-MS friction material testing machine. The surface structure of carbon fiber reinforced friction materials was analyzed\\u000a by scanning electronic microscopy (SEM).

Du-qing Cheng; Xue-tao Wang; Jian Zhu; Dong-hua Qiu; Xiu-wei Cheng; Qing-feng Guan

2009-01-01

336

Analytical Investigation on Squeal Phenomena Generated in Bicycle Disc Brakes  

Microsoft Academic Search

The squeal phenomenon is often generated in bicycle disc brakes. This paper deals analytically with the generation mechanism and the criterion of whether or not the squeal occurs. According to the experimental studies, it has been made clear that the squeal is mainly in-plane vibration in the direction of disc surface with the frequency about 1kHz caused by frictional characteristics

Takashi Nakae; Atsuo Sueoka; Takahiro Ryu

2010-01-01

337

Fuzzy throttle and brake control for platoons of smart cars  

Microsoft Academic Search

Additive fuzzy systems can control the velocity and the gap between cars in single-lane platoons. The overall system consists of throttle and brake controllers. We first designed and tested a throttle-only fuzzy system on a validated car model and then with a real car on highway 1–15 in California. We used this controller to drive the “smart” car on the

Hyun Mun Kim; Julie Dickerson; Bart Kosko

1996-01-01

338

Estimation of Driving Phase by Modeling Brake Pressure Signals  

Microsoft Academic Search

\\u000a It is important for a driver-assist system to know the phase of the driver, that is, safety or danger. This paper proposes\\u000a two methods for estimating the driver’s phase by applying machine learning techniques to the sequences of brake signals. One\\u000a method models the signal set with a mixture of Gaussians, where a Gaussian corresponds to a phase. The other

Hiroki Mima; Kazushi Ikeda; Tomohiro Shibata; Naoki Fukaya; Kentarou Hitomi; Takashi Bando

2009-01-01

339

An unusual intraorbital foreign body: A brake lever  

PubMed Central

Orbital trauma usually affects the bony parts of the orbit; however, in rare cases foreign bodies are found within the orbit. In this report, we introduce a case with unusual large intraorbital foreign bodies (two parts of a brake lever) after a motorcycle accident. Although one of the foreign bodies was located in the posterior orbit, they required only one simple operation for retrieval. We will discus the management strategy.

Nowroozzadeh, Mohammad Hosein

2009-01-01

340

Molecular brake systems controlled by light and heat  

Microsoft Academic Search

Machines at a molecular level are in perpetual Brownian motion even at an ambient temperature. One of the representative issues\\u000a of researches on molecular machines is a development of technology, which can control Brownian motion. This review presents\\u000a our efforts to achieve the first rationally designed molecular brake systems of threading\\/dethreading motions, a shuttling\\u000a motion, and a rocking motion that

Keiji Hirose

2010-01-01

341

Positive safety brake for oil well pumping apparatus  

SciTech Connect

A safety brake adapted for positively locking the crank and counter-balance weights of oil well pumping apparatus against rotation, particularly for placement and servicing of the pumping unit is described. In the preferred embodiment shown, a cylindrical member is bolted to a brake drum which rotates in combination with the shaft from the gear box carrying the crank and counter-balance weights. The cylindrical member has a plurality of holes disposed about its periphery. A movable engaging bar is rotatably carried on a shaft mounted to a bracket adapted for connection to the bearing cap on the gear box adjacent the brake drum. The bar contains a locking tongue for engaging the holes in the cylindrical member. The bar is rotatable from a position engaged with the cylindrical member and a position removed therefrom. A spring bias is provided to hold the bar in either of the two positions. Additionally, a jerk bar, having a hammer weight thereon and a handle portion, is provided for striking the lock bar to forceably disengage the locking tongue from a hole of the cylindrical member when under rotational force.

Delaney, G.

1981-06-30

342

Engine shut-off system with flywheel braking  

SciTech Connect

A system is disclosed for quickly stopping the internal combustion engine of a powered implement having a deadman control normally biased toward a first position and acutable by the implement operator to a second position and having an operator actuable engine starting mechanism. The engine has a flywheel coupled thereto for rotation with the engine crankshaft and that flywheel is provided with an annular friction surface disposed generally in a plane normal to the axis of rotation of the flywheel. A braking member having a second friction surface is normally biased into engagement with the annular friction surface of the flywheel and coupled to the deadman control so that the two friction surfaces will be disengaged upon movement of the deadman control to a second or operational position by the implement operator. An arrangement for disabling the engine starting mechanism while the friction surfaces are engaged and an arrangement for disabling the engine ignition system when the deadman control is released are disclosed. The braking member may move into engagement by pivotal movement, movement perpendicular to the flywheel annular friction surface, or by moving generally parallel to the flywheel annular surface and into engagement with a ramp forcing the braking member toward the flywheel surface.

Kyonich, P.G.; Ayendt, D.R.

1983-07-26

343

Motion control of passive mobile robot with multiple casters based on feasible braking force and moment  

Microsoft Academic Search

We introduce a passive mobile robot called CPRP (Caster-type Passive Robot Porter). This robot consists of multiple casters with servo brakes and a controller. C-PRP employs passive dynamics with respect to the force applied by a human. Its appropriate motion is controlled using the servo brakes. In this paper, we derive and analyze a feasible braking force\\/moment that can be

Masao Saida; Yasuhisa Hirata; Kazuhiro Kosuge

2010-01-01

344

Microstructure and frictional properties of C\\/SiC brake materials with sandwich structure  

Microsoft Academic Search

C\\/SiC brake materials with a sandwich structure were prepared by three step process, chemical vapor infiltration, slurry infiltration and liquid silicon infiltration process. The fabricated brake materials consist of a C-fiber rich main body and two SiC-rich frictional layers on the surface. The microstructure and frictional properties of C\\/SiC brake materials were investigated. The results indicated that the density and

Shangwu Fan; Litong Zhang; Laifei Cheng; Shangjie Yang

2011-01-01

345

Development of Brake-by-Wire Hardware-in-Loop Simulation Bench  

Microsoft Academic Search

This paper mainly describes a PC-based Brake-By-Wire Hardware-In-Loop-simulation Bench which has high efficiency and applicability. System architecture, hardware configuration, and software model of this bench are presented in details. The electric braking controllers collect, process and transfer all kinds of information, and generate simultaneous control codes according to the control algorithm, then drive electromechanical actuator and braking parts. For improving

Jun Liu; Yongling Fu; Zhanlin Wang; Juan Chen

2012-01-01

346

Development of Brake-By-Wire Hardware-In-Loop Simulation Bench  

Microsoft Academic Search

This paper mainly describes a PC-based Brake-By-Wire Hardware-In-Loop-simulation Bench which has high efficiency and applicability. System architecture, hardware configuration, and software model of this bench are presented in details. The electric braking controllers collect, process and transfer all kinds of information, and generate simultaneous control codes according to the control algorithm, then drive electromechanical actuator and braking parts. For improving

Jun Liu; Yongling Fu; Zhanlin Wang; Juan Chen

2012-01-01

347

Wear mechanism of disc-brake block material for new type of drilling rig  

Microsoft Academic Search

To improve friction and wear performance and service life of the disc-brake pair material of a drilling rig, a new type of\\u000a asbestos-free frictional material with better performance for disc-brake blocks is developed, and its wear mechanism is investigated\\u000a by friction and wear experiments. Topography and elementary components of the brake block’s wear surface are analyzed by employing\\u000a SEM and

Xinhua Wang; Simin Wang; Siwei Zhang; Deguo Wang

2008-01-01

348

Exposure to Asbestos During Brake Maintenance of Automotive Vehicles by Different Methods  

Microsoft Academic Search

Asbestos concentrations were measured during the different operations of brake maintenance of passenger cars, trucks and buses in 24 Finnish workplaces. The estimated average asbestos exposure during the workday (8-hr time-weighted average) was 0.1–0.2 fibers\\/cm during brake repair of trucks or buses, and under 0.05?f\\/cm during repair of passenger car brakes when the background concentration was not included in the

TIMO KAUPPINEN; KARI KORHONEN

1987-01-01

349

Braking Energy Regeneration System of Buses Based on Compressed Air Energy Storage  

Microsoft Academic Search

Brake energy regeneration is an electrical current management technology that ensures intelligent generation of electric power\\u000a by restricting production to the engine overrun phases and the application of the brakes. Compressed air energy storage is\\u000a a technically feasible and economically attractive method for load management. This work proposed a brake energy regeneration\\u000a system based on electric-controlled compressed air energy storage

Wei-gang Zhang; Ying-duo Han; Feng-ling Li

2007-01-01

350

Identification of brake wear particles and derivation of a quantitative tracer for brake dust at a major road  

NASA Astrophysics Data System (ADS)

Traffic-generated air pollutant emissions can be classified into exhaust and non-exhaust emissions. Increased attention is focussing on non-exhaust emissions as exhaust emissions are progressively limited by regulations. To characterise metal-rich emission from abrasion processes, size-segregated analysis of atmospheric aerosol particles sampled with micro-orifice uniform deposit impactors (MOUDI) in March 2007 in London was performed. The samples were collected at a roadside and a background site and were analysed for Al, Ba, Cu, Fe, Sb, Ti, V, Zn, Ca 2+, K +, Mg 2+, Na +, and NH 4+. Most components showed a clear roadside increment, which was evident as a higher mass concentration and a change in the size distribution. In particular, Fe, Cu, Ba, and Sb correlated highly, indicative of a common traffic-related source. Using complementary information on the fleet composition, vehicle number and average speed, the brake wear emission was calculated using the EMEP/CORINAIR emission database. The total PM 10 and barium emission of the traffic was determined by ratio to NO x whose source strength was estimated from published emission factors. Barium was found to comprise 1.1% of brake wear (PM 10) particles from the traffic fleet as a whole, allowing its use as a quantitative tracer of brake wear emissions at other traffic-influenced sites.

Gietl, Johanna K.; Lawrence, Roy; Thorpe, Alistair J.; Harrison, Roy M.

2010-01-01

351

Optimal design of a novel hybrid MR brake for motorcycles considering axial and radial magnetic flux  

NASA Astrophysics Data System (ADS)

This work presents an optimal solution of a new type of motorcycle brake featuring different smart magnetorheological (MR) fluids. In this study, typical types of commercial MR fluid are considered there for the design of a motorcycle MR brake; MRF-122-2ED (low yield stress), MRF-132-DG (medium yield stress) and MRF-140-CG (high yield stress). As a first step, a new configuration featuring a T-shaped drum MR brake is introduced and a hybrid concept of magnetic circuit (using both axial and radial magnetic flux) to generate braking force is analyzed based on the finite element method. An optimal design of the MR brake considering the required braking torque, the temperature due to friction of the MR fluid, the mass of the brake system and all significant geometric dimensions is then performed. For the optimization, the finite element analysis (FEA) is used to achieve principal geometric dimensions of the MR brake. In addition, the size, mass and power consumption of three different MR motorcycle brakes are quantitatively analyzed and compared.

Nguyen, Q. H.; Choi, S. B.

2012-05-01

352

A new structure of a magnetorheological brake with the waveform boundary of a rotary disk  

NASA Astrophysics Data System (ADS)

This paper presents a novel magnetorheological (MR) brake design incorporating a rotary disk with a waveform boundary that generates a resistance force based on the effects of a material deformation process. This force is transmitted from an external agent and creates the necessary energy for breaking the structure of the hardened MR fluid. Its minimum destructive ability is proportional to the variable stiffness of an MR fluid in a magnetic field. In this design, the waveform wall of a rotary disk crushes the particles chains (fibrils) of the MR fluid together instead of breaking them via strain in a conventional MR brake. The resistance forces and braking torques generated by this crush action are stronger than those produced by strain action. To verify our proposed MR brake, the proposed and conventional MR brakes are designed using similar magnetic circuits and material parameters. We compared the performance of our novel MR brake to the performance of a conventional MR brake, and demonstrated that the measured resistance torque of the proposed MR brake is approximately 600% greater than resistance torques generated by conventional brakes.

Hai Nam, Tran; Ahn, Kyoung Kwan

2009-11-01

353

WHY DO THE BRAKING INDICES OF PULSARS SPAN A RANGE OF MORE THAN 100 MILLIONS?  

SciTech Connect

Here we report that the observed braking indices of the 366 pulsars in the sample of Hobbs et al. range from about -10{sup 8} to about +10{sup 8} and are significantly correlated with their characteristic ages. Using the model of magnetic field evolution we developed previously based on the same data, we derive an analytical expression for the braking index which agrees with all the observed statistical properties of the braking indices of the pulsars in the sample of Hobbs et al. Our model is, however, incompatible with the previous interpretation that magnetic field growth is responsible for the small values of braking indices (<3) observed for ''baby'' pulsars with characteristic ages of less than 2 Multiplication-Sign 10{sup 3} yr. We find that the ''instantaneous'' braking index of a pulsar may be different from the ''averaged'' braking index obtained from fitting the data over a certain time span. The close match between our model-predicted ''instantaneous'' braking indices and the observed ''averaged'' braking indices suggests that the time spans used previously are usually smaller than or comparable to their magnetic field oscillation periods. Our model can be tested with the existing data by calculating the braking index as a function of the time span for each pulsar. In doing so, one can obtain for each pulsar all the parameters in our magnetic field evolution model, and may be able to improve the sensitivity of using pulsars to detect gravitational waves.

Zhang Shuangnan; Xie Yi, E-mail: zhangsn@ihep.ac.cn [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

2012-12-20

354

A parametric study of golf car and personal transport vehicle braking stability and their deficiencies.  

PubMed

This paper describes research and parametric analyses of braking effectiveness and directional stability for golf cars, personal transport vehicles (PTVs) and low speed vehicles (LSVs). It is shown that current designs, which employ brakes on only the rear wheels, can lead to rollovers if the brakes are applied while traveling downhill. After summarizing the current state of existing safety standards and brake system designs, both of which appear deficient from a safety perspective, a previously developed dynamic simulation model is used to identify which parameters have the greatest influence on the vehicles' yaw stability. The simulation results are then used to parametrically quantify which combination of these factors can lead to yaw induced rollover during hard braking. Vehicle velocity, steering input, path slope and tire friction are all identified as important parameters in determining braking stability, the effects of which on rollover propensity are presented graphically. The results further show that when vehicles are equipped with front brakes or four-wheel brakes, the probability of a yaw induced rollover is almost entirely eliminated. Furthermore, the parametric charts provided may be used as an aid in developing guidelines for golf car and PTV path design if rear brake vehicles are used. PMID:19540974

Seluga, Kristopher J; Baker, Lowell L; Ojalvo, Irving U

2009-05-12

355

Real-Time Dynamic Brake Assessment Proof of Concept Final Report  

SciTech Connect

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 30 mph). Data was collected at 10 Hz. Standard and stepped-pressure performance-based brake tests with brake pressure transducers were performed for each loading condition. The stepped-pressure test included the constant-pressure intervals of brake application at 15, 20, 25, and 30 psi. The PBBT data files included 10 Hz streaming data collected during the testing of each axle. Two weeks of real-world duty cycle (driving and braking) data was also collected at 10 Hz. Initial analysis of the data revealed that the data collected in the field (i.e., day-to-day operations) provided the same information as that obtained from the controlled tests. Analysis of the data collected revealed a strong linear relationship between brake application pressure and deceleration for given GVWs. As anticipated, initial speed was not found to be a significant factor in the deceleration-pressure relationship, unlike GVW. The positive results obtained from this proof of concept test point to the need for further research to expand this concept. A second phase should include testing over a wider range of speeds and include medium brake application pressures in addition to the low pressures tested in this research. Testing on multiple vehicles would also be of value. This future phase should involve testing to determine how degradation of braking performance affects the pressure-deceleration relationship.

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

2011-11-01

356

NHTSA (National Highway Traffic Safety Administration) Heavy Duty Vehicle Brake Research Program Report No. 4 - Stopping Capability of Hydraulically Braked Vehicles. Volume 5. Appendices I-M.  

National Technical Information Service (NTIS)

The volume contains Appendices I, J, K, L and M to the technical report (Volume I). Each appendix includes all of the test data collected for a particular vehicle that was evaluated in the test program along with photographs, vehicle information sheets, a...

R. L. Kirkbride R. W. Radlinski

1985-01-01

357

NHTSA (National Highway Traffic Safety Administration) Heavy Duty Vehicle Brake Research Program Report No. 4 - Stopping Capability of Hydraulically Braked Vehicles. Volume 2. Appendices A-C.  

National Technical Information Service (NTIS)

The volume contains Appendices A, B and C to the technical report (Volume I). Each appendix includes all of the test data collected for a particular vehicle that was evaluated in the test program along with photographs, vehicle information sheets, and sum...

R. L. Kirkbride R. W. Radlinski

1985-01-01

358

TU Delft: Hydraulic Engineering  

NSDL National Science Digital Library

Given the Dutch reputation for water management, it's no surprise that one of their leading technical institutes, The Technische Universiteit Delft, offers a program in Hydraulic Engineering. The website, in both Dutch and English, describes their program as an attempt "to bridge the gap between basic sciences (fluid mechanics and soil mechanics in particular) and practical engineering applications in the design, construction, maintenance, management and eventually the demolition of hydraulic structures." The Education section of the website posts MSc theses completed by their students. The research section describes current and recently completed research projects and includes a listing of publications, some of which are available to download. The website also has a link to a Hydraulic Engineering portal, which offers various publication databases (some in Dutch only), and the Civil Engineering Knowledge Centre, which provides library access and discussion forums for students and staff of Civil Engineering.

359

What Is Hydraulic Fracturing?  

NSDL National Science Digital Library

Hydraulic fracturing is a process used in nine out of 10 natural gas wells in the United States, where millions of gallons of water, sand and chemicals are pumped underground to break apart the rock and release the gas. Scientists are worried that the chemicals used in fracturing may pose a threat either underground or when waste fluids are handled and sometimes spilled on the surface. This poster presentation illustrates the under surface process of hydraulic fracking and the distribution flow to the market.

2012-01-01

360

Laboratory Determination of Hydraulic Conductivity  

NSDL National Science Digital Library

From D.B. McWhorterand D. K. Sunda's 1977 Ground-Water Hydrology and Hydraulics, this two page excerpt outlines and details Laboratory Determination of Hydraulic Conductivity. Here, visitors will find illustrations and formula to understand the concept.

2008-02-07

361

Development of Lightweight Hydraulic Supports.  

National Technical Information Service (NTIS)

After evaluating preceding studies and designs of lightweight supports, the all-hydraulic and the hydromechanical concepts were selected for detailed design and fabrication. Further analysis and testing showed that the all-hydraulic design was economicall...

P. T. Alexander

1982-01-01

362

Preliminary Survey Report: Evaluation of Brake Drum Service Controls at Pennsylvania Bureau of Vehicle Management, Vehicle Maintenance Division, Harrisburg, Pennsylvania.  

National Technical Information Service (NTIS)

Exposure to asbestos (1332214) during the servicing of brakes on state owned vehicles at the Bureau of Vehicle Management Maintenance Division (SIC-7538), Harrisburg, Pennsylvania, was investigated as part of a study of control technologies. Brakes had be...

H. D. Van Wagenen

1987-01-01

363

Rotational Resonance of Nonaxisymmetric Magnetic Braking in the KSTAR Tokamak  

NASA Astrophysics Data System (ADS)

One of the important rotational resonances in nonaxisymmetric neoclassical transport has been experimentally validated in the KSTAR tokamak by applying highly nonresonant n=1 magnetic perturbations to rapidly rotating plasmas. These so-called bounce-harmonic resonances are expected to occur in the presence of magnetic braking perturbations when the toroidal rotation is fast enough to resonate with periodic parallel motions of trapped particles. The predicted and observed resonant peak along with the toroidal rotation implies that the toroidal rotation in tokamaks can be controlled naturally in favorable conditions to stability, using nonaxisymmetric magnetic perturbations.

Park, J.-K.; Jeon, Y. M.; Menard, J. E.; Ko, W. H.; Lee, S. G.; Bae, Y. S.; Joung, M.; You, K.-I.; Lee, K.-D.; Logan, N.; Kim, K.; Ko, J. S.; Yoon, S. W.; Hahn, S. H.; Kim, J. H.; Kim, W. C.; Oh, Y.-K.; Kwak, J.-G.

2013-08-01

364

Dynamic calibration of mechanically, air- and electromagnetically braked cycle ergometers.  

PubMed

In this study we measured the accuracy of the following types of cycle ergometer against the criterion of a dynamic calibration rig (DCR): 35 friction-braked (Monark), 5 research-grade air-braked (Repco) and 5 electromagnetically braked (2 Siemens, 1 Elema-Schonander, 1 Ergoline, 1 Warren E. Collins). Monark ergometer power outputs over the range 58.9-353.2 W significantly (P < 0.001) underestimated those registered by the DCR with mean accuracies of 91.7-97.8%. The least accurate individual reading for each of the six up-scale (0-353.2 W) power outputs ranged from 81.6 to 91.6%; corresponding down-scale (353.2-0 W) accuracies were 85.1-92.5%. A hysteresis effect was furthermore evident for this ergometer in that up-scale measurements were significantly (P < 0.05) greater than down-scale ones. In addition, when the oldest [mean (SD): 11.3 (2.3) years old] and newest [1.4 (0.8) years old] eight ergometers were compared, the latter were significantly (P < 0.05) more accurate over the range 117.7-294.3 W. Apart from the two lowest power outputs of 47 W (62.2-96.0% accuracy) and 127 W (88.0-97.7% accuracy), the individual up-scale and down-scale accuracies of the Repco ergometers ranged from 98.0 to 104.2% for power outputs of 272.7-1137.8 W and the means were not significantly different from those of the DCR. There was also no evidence of hysteresis. Except for the initial power output of 50 W (40 rev/min: 83.8-99.2% accuracy; 60 rev/min: 93.2-122.6% accuracy), the individual accuracies of the electromagnetically braked ergometers ranged from 89.3 to 101.4% over the up-scale range of 100-400 W, and none of the means were significantly different from those of the DCR. The variability of individual errors for the preceding data emphasises that all cycle ergometers should be validated against the criterion of a DCR if accurate power outputs are required. PMID:9754975

Maxwell, B F; Withers, R T; Ilsley, A H; Wakim, M J; Woods, G F; Day, L

1998-09-01

365

Tachyon cosmology, supernovae data, and the big brake singularity  

SciTech Connect

We compare the existing observational data on type Ia supernovae with the evolutions of the Universe predicted by a one-parameter family of tachyon models which we have introduced recently [Phys. Rev. D 69, 123512 (2004)]. Among the set of the trajectories of the model which are compatible with the data there is a consistent subset for which the Universe ends up in a new type of soft cosmological singularity dubbed big brake. This opens up yet another scenario for the future history of the Universe besides the one predicted by the standard {lambda}CDM model.

Keresztes, Z.; Gergely, L. A.; Gorini, V.; Moschella, U.; Kamenshchik, A. Yu. [Department of Theoretical Physics, University of Szeged, Tisza Lajos krt 84-86, Szeged 6720 (Hungary); Department of Experimental Physics, University of Szeged, Dom Ter 9, Szeged 6720 (Hungary); Department of Theoretical Physics, University of Szeged, Tisza Lajos krt 84-86, Szeged 6720 (Hungary); Department of Experimental Physics, University of Szeged, Dom Ter 9, Szeged 6720 (Hungary); Department of Applied Science, London South Bank University, 103 Borough Road, London SE1 OAA (United Kingdom); Dipartimento di Scienze Fisiche e Mathematiche, Universita dell'Insubria, Via Valleggio 11, 22100 Como (Italy); INFN, sezione di Milano, Via Celoria 16, 20133 Milano (Italy); Dipartimento di Fisica and INFN, via Irnerio 46, 40126 Bologna (Italy); L. D. Landau Institute for Theoretical Physics, Russian Academy of Sciences, Kosygin street 2, 119334 Moscow (Russian Federation)

2009-04-15

366

46 CFR 28.880 - Hydraulic equipment.  

Code of Federal Regulations, 2010 CFR

...Hydraulic equipment. (a) Each hydraulic system must be so designed and installed...operating pressure. (c) Each hydraulic system must be equipped with at least... (d) All material in a hydraulic system must be suitable for use...

2009-10-01

367

46 CFR 28.405 - Hydraulic equipment.  

Code of Federal Regulations, 2010 CFR

...Hydraulic equipment. (a) Each hydraulic system must be so designed and installed...operating pressure. (c) Each hydraulic system must be equipped with at least... (d) All material in a hydraulic system must be suitable for use...

2009-10-01

368

46 CFR 28.880 - Hydraulic equipment.  

Code of Federal Regulations, 2010 CFR

...Hydraulic equipment. (a) Each hydraulic system must be so designed and installed...operating pressure. (c) Each hydraulic system must be equipped with at least... (d) All material in a hydraulic system must be suitable for use...

2010-10-01

369

Freewheeling hydraulic power mills  

Microsoft Academic Search

Components of free-wheeling power plants that use the hydraulic forces of winds or water currents are described. Fore and aft cones to increase throughput, multiple impellers driving a single rotor, swivel mounts to support nacelles, dc electrolytic cells for the production of H2 and O2, and cryogenic storage systems for the gases are the principle elements in the power mill

F. F. Hall

1979-01-01

370

Hydraulic type starting clutch  

Microsoft Academic Search

This patent describes a hydraulic type starting clutch comprising: an input shaft; an input rotating member arranged for rotation in unison with the input shaft; an output shaft; an output rotating member arranged for rotation in unison with the output shaft; friction plates interposed between the input rotating member and the output rotating member for engagement to transmit torque from

K. Ohzono; K. Hayashi; M. Saito; M. Kato; Y. Yoshida

1987-01-01

371

Water Treatment Technology - Hydraulics.  

ERIC Educational Resources Information Center

|One of twelve water treatment technology units, this student manual on hydraulics provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: head loss in pipes in series, function loss in…

Ross-Harrington, Melinda; Kincaid, G. David

372

Integration in Hydraulics.  

ERIC Educational Resources Information Center

|This paper presents an application of integration to the field of hydraulics. An integral relation for the time required to drop the fluid contained in a cylindrical tank from one level to another using a hole in the tank wall is derived. Procedures for constructing the experimental equipment and procedures for determining the coefficient of…

Sworder, Steven C.

373

Hydraulic fracturing process  

Microsoft Academic Search

A process is described for hydraulically fracturing a permeable subterranean formation in which the fracture faces are treated to reduce their permeability to the fracturing fluid. Propping agent is placed in the fracture in a conventional manner whereby the bulk of the propping agent is deposited in the fracture at a location remote from the well. Thereafter the fracture faces

Pye

1973-01-01

374

Hydraulic fracturing propping agent  

SciTech Connect

A high strength propping agent for use in hydraulic fracturing of subterranean formations comprising solid, spherical particles having an alumina content of between 40 and 60%, a density of less than 3.0 gm/cc and an ambient temperature permeability of 100,000 or more millidarcies at 10,000 psi.

Lunghofer, E. P.

1985-06-11

375

Hydraulic fracturing technique  

Microsoft Academic Search

This improved hydraulic fracturing method consists of injecting into previously formed fractures filled with a very viscous fluid, a relatively nonviscous fluid containing sand or other propping agent material. The low viscosity fluid fingers through the high viscosity fluid in radial channels and when the fingers containing the propping agent reach the extremity of the highly viscous fluid, they mushroom

1965-01-01

376

Hydraulic fracturing propping agent  

Microsoft Academic Search

A high strength propping agent for use in hydraulic fracturing of subterranean formations comprising solid, spherical particles having an alumina content of between 40 and 60%, a density of less than 3.0 gm\\/cc and an ambient temperature permeability of 100,000 or more millidarcies at 10,000 psi.

Lunghofer

1985-01-01

377

Blast Field Produced by a Cannon Having a Perforated Muzzle Brake.  

National Technical Information Service (NTIS)

In a study of perforated muzzle brakes, Nagamatsu, Choi, Duffy, and Carofano calculated the three-dimensional steady flow through one vent hole and used the results to predict overall brake performance. In the present study, the analysis is extended to th...

G. C. Carofano

1988-01-01

378

Effects of inertial load and velocity on the braking process of voluntary limb movements  

Microsoft Academic Search

The aim of this study has been to identify, in humans, the braking process underlying voluntary forearm movements performed at various velocities and amplitudes and against different inertial loads. The procedure used to estimate the parameters of the braking process involved kinematic analysis of the movement and measurement of alpha-motoneural input to flexor and extensor muscles by recording electromyographic (EMG)

F. Lestienne

1979-01-01

379

Analysis of braking operations in present-day electric drives with asynchronous motors  

Microsoft Academic Search

The extensive use of microprocessors and electronic devices in electrical drives allows realization of easily improved braking operation with asynchronous motors. This paper presents a fast braking technique for a complete stop of induction motors. This technique is validated by simulation tests under different operating conditions

M. Covino; M. L. Grassi; E. Pagano

1997-01-01

380

Selection and cost of brakes for horizontal axis stall regulated wind turbines. Appendices.  

National Technical Information Service (NTIS)

This report is intended to provide an understanding of how an electrodynamic brake can be used as the primary braking system is a fixed pitch, horizontal axis wind turbine with an induction generator. The work is based on theoretical and experimental rese...

N. La White

1993-01-01

381

Calibration, Information, and Control Strategies for Braking to Avoid a Collision  

ERIC Educational Resources Information Center

|This study explored visual control strategies for braking to avoid collision by manipulating information about speed of self-motion. Participants watched computer-generated displays and used a brake to stop at an object in the path of motion. Global optic flow rate and edge rate were manipulated by adjusting eyeheight and ground-texture size.…

Fajen, Brett R.

2005-01-01

382

Gap variation in a brake mechanism with an automatically controlled crank  

Microsoft Academic Search

The mathematical description of gap variation in brake gear of drum type intended for truck vehicle with invariant automatic\\u000a control lever has been presented. It is examined the impact of the adjustment gap, brake shoes wear, and drum temperature\\u000a expansion.

Yu. A. Golubev

2009-01-01

383

THERMOELASTO-PLASTIC STRESSES AND THERMAL DISTORTIONS IN A BRAKE DRUM  

Microsoft Academic Search

Most analyses of thermal stresses generated in a brake drum are studies within either an elastic or a plastic region with constant yield strength. As a matter of fact, however, a severe brake application will create a thermal environment on the friction surface with an excessively high surface temperature. At a high temperature, the degradation of yield strength of a

Masashi Daimaruya; Hidetoshi Kobayashi; Khairul Fuad

1997-01-01

384

Modeling, sensitivity analysis, and design optimization of automotive brakes for squeal reduction  

Microsoft Academic Search

A numerical modeling approach is developed for an automotive drum brake system for squeal prediction, a sensitivity analysis is presented to analyze the influences of parameters on system stability, and structural optimization is performed to find the optimal solution for squeal reduction. ^ The brake system model is based on the component modal information, which is found by Finite Element

Jinchun Huang

2005-01-01

385

Modeling and control design for a computer-controlled brake system  

Microsoft Academic Search

The brake subsystem is one of the most significant parts of a vehicle with respect to safety. A computer-controlled brake system has the capability of acting faster than the human driver during emergencies, and therefore has the potential of improving safety of the vehicles used in the future intelligent transportation systems (ITSs). In this paper we consider the problem of

Humair Raza; Zhigang Xu; Bingen Yang; Petros A. Ioannou

1997-01-01

386

An Assessment of the Dunlop Maxaret Anti-Locking Braking System Fitted to an Articulated Vehicle.  

National Technical Information Service (NTIS)

Jack-knifing of articulated vehicles is usually caused by the locking of the tractor rear wheels when brakes are applied. A method of preventing jack-knifing is to use an anti-locking braking system to ensure that these wheels do not lock. This report des...

H. A. Wilkins

1968-01-01

387

Aircraft Braking Friction Trials on a Coarse Open Graded Macadam Runway Surface.  

National Technical Information Service (NTIS)

Accelerate-brake trials were made on a coarse open graded macadam runway surface, with a Scimitar Mk.1 aircraft to measure braking friction in wet conditions. For comparison, trials were also made on grooved and ungrooved asphalt surfaces. The grooving wa...

E. J. Key E. M. Minter

1969-01-01

388

Reassessment of the Wear of Cooper-Based Brake Material at Elevated Temperatures.  

National Technical Information Service (NTIS)

In a comprehensive study of copper-based brake material sliding against 1722-AS steel, as used in aircraft, Ho and Peterson concluded that the wear Delta W of brake material was proportional to surface temperature relative to the melting point T sub m of ...

F. F. Ling M. B. Peterson

1985-01-01

389

Compositional effects of the brake friction material on creep groan phenomena  

Microsoft Academic Search

Creep groan (low frequency frictional vibration in the range of 200–500Hz during braking at a very low vehicle speed) was studied by changing the relative amounts of ingredients in a brake friction material containing 12 ingredients. Twenty-nine friction material specimens with different relative amounts of the ingredients were manufactured according to a constrained mixture design. The difference (??) between kinetic

H. Jang; J. S. Lee; J. W. Fash

2001-01-01

390

Effects of water films and sliding speed on the frictional behavior of truck disc brake materials  

Microsoft Academic Search

Friction materials for car and truck disc brake pads are typically complex composites containing metals, ceramics, and polymers that are designed to provide stable frictional performance over a range of vehicle operating conditions, exhibit acceptable wear life, and produce minimal noise and vibration. Despite the fact that brakes must operate under a variety of environmental conditions, most standardized and developmental

P. J. Blau; J. C. McLaughlin

2003-01-01

391

Effects of moisture adsorption on laboratory wear measurements of brake friction materials  

Microsoft Academic Search

As is the case for tribological systems in general, the wear of brake friction materials, sliding against brake discs or drums, is influenced by many factors. This dependency requires very complicated test matrices in order to characterize the range of lining wear properties. Furthermore, the wear rate is very low under normal operating conditions, and thus a substantial amount of

Kwangjin Lee; Peter J. Blau; John J. Truhan

2007-01-01

392

Wear of truck brake lining materials using three different test methods  

Microsoft Academic Search

Frictional stability and wear resistance are key performance requirements for heavy truck brake linings. Lining-counterface friction affects the rate of vehicle deceleration, but wear also affects stopping characteristics because uneven or high wear can alter the contact geometry of the lining, change the pattern of frictional heat generation, and degrade the response of the braking system. Inertia dynamometer wear tests

Peter J. Blau; Brian C. Jolly

2005-01-01

393

Nonlinear Analysis of Chatter Phenomena Generated in a Bicycle Disc Brake  

Microsoft Academic Search

Squeal and chatter phenomena are often generated in bicycle disc brakes. The squeal is in-plane unstable vibration along the disc surface caused by dry friction with negative slope with respect to the relative velocity. The squeal is generated in the vibrating system including the brake unit, spokes and hub. According to experiments, the chatter is generated in a certain limited

Takashi Nakae; Takahiro Ryu; Atsuo Sueoka

2010-01-01

394

Research on braking of battery-supplied interior permanent magnet motor driving system  

Microsoft Academic Search

This paper focuses on the braking of interior permanent magnet synchronous machine (IPMSM) driving system. IPMSM motor has strong rotor saliency and extended constant power operating range and is widely used in the field of electrical traction. In the battery-supplied electric drive system, energy saving becomes critical because of the limited energy. Proper braking must be done to feed back

Guangzhao Luo; Zhe Chen; Yantao Deng; Manfeng Dou; Weiguo Liu

2009-01-01

395

Regenerative-braking sliding mode control of electric vehicle based on neural network identification  

Microsoft Academic Search

Aiming at the main problems of electric vehicle (EV): short driving range, short life of batteries, and variation of model parameters, based on constructing the main circuit diagram of the EVpsilas control system, the mathematical model of regenerative-braking process was established, and a novel regenerative-braking controller was designed, which combined neural network (NN) with traditional sliding mode controller (SMC). The

Jianbo Cao; Binggang Cao; Peng Xu; Zhifeng Bai

2008-01-01

396

Toxic effects of brake wear particles on epithelial lung cells in vitro  

Microsoft Academic Search

BACKGROUND: Fine particulate matter originating from traffic correlates with increased morbidity and mortality. An important source of traffic particles is brake wear of cars which contributes up to 20% of the total traffic emissions. The aim of this study was to evaluate potential toxicological effects of human epithelial lung cells exposed to freshly generated brake wear particles. RESULTS: An exposure

Michael Gasser; Michael Riediker; Loretta Mueller; Alain Perrenoud; Fabian Blank; Peter Gehr; Barbara Rothen-Rutishauser

2009-01-01

397

Antilock brakes and risk of front and rear impact in two-vehicle crashes  

Microsoft Academic Search

While antilock brakes (ABS) have been convincingly demonstrated to enhance test track braking performance, their effect on crash risk in actual driving has been less clear. This research was conducted to seek clear associations between ABS and risk of involvement in one particular class of crashes, namely, two-vehicle crashes, particularly on wet roads. Police reported crashes in which a following

Leonard Evans; Peter H. Gerrish

1996-01-01

398

Application of AMESim software to the device producing fluctuant load for vehicle braking system  

Microsoft Academic Search

In order to improve controlling quantity of ABS, this paper presents a method to study the characteristics of the device producing fluctuant load for vehicle braking system, which is a new system to improve vehicle security and investigate the brake performance, through commercial software. The first part introduces the configurations of the device producing fluctuant load. In the second part,

Hongxing Deng; Xianbin Wang; Wenhui Zhang

2010-01-01

399

A linear eddy current braking system defined by finite element method  

Microsoft Academic Search

The authors propose in this paper the modelling and computing of a linear eddy current braking system by the finite element method. This braking system will be used in a high speed train. They study this device in 2D and 3D taking into account nonlinearities such as saturation and the displacement of the train. The authors present many results detailing

M. Hecquet; P. Brochet; Lee Sang Jin; P. Delsalle

1999-01-01

400

Asbestos Fibre Concentrations in the Lungs of Brake Workers: Another Look  

Microsoft Academic Search

Objective: To reanalyse data on the lung content of asbestos fibres among brake mechanics. Methods: I re-analysed data published by Butnor, Roggli and colleagues on the lung content of chrysotile and tremolite asbestos fibres among brake mechanics and controls. Statistics of the distributions were estimated by maximum likelihood to accommodate observations below the detection limit. Mean concentrations were compared by

MURRAY M. FINKELSTEIN

2008-01-01

401

A customized hand cycle brake system to improve safety and performance for quadriplegic users  

Microsoft Academic Search

Quadriplegic hand cycles currently on the market possess brakes that are located in areas that create a safety hazard due to the user's limited hand functionality. The customized mechanical and electronic braking system presented here will allow for enhanced performance, eliminating this safety issue. To ensure the effectiveness of the system, a minimum force test was performed on the mechanical

Paige Armstrong; Kate Cox; Cindy Hassler; Danielle Sack

2011-01-01

402

Class 8 Mack Straight Emulating a Refuse Hauler: Braking Improvement Study.  

National Technical Information Service (NTIS)

The effect of higher output foundation brakes were determined for a Class 8, Mack 6x4 MR-688-S straight truck which emulated a McNeilus refuse hauler. Four brake types studied included: original hybrid S-cam drums, big S-cam drums, hybrid disc, and all-di...

R. L. Hoover T. R. Van Buskirk W. R. Garrott

2013-01-01

403

Investigation of Health Hazards in Brake Lining Repair and Maintenance Workers Occupationally Exposed to Asbestos.  

National Technical Information Service (NTIS)

There are several sources of asbestos exposure to garage mechanics and automobile repairmen. First, of course, is that the asbestos exposure from the debris of brake or clutch lining wear, particulary when the brake or clutch housing are cleaned using a h...

W. J. Nicholson S. M. Daum W. V. Lorimer H. Velez R. Lilis

1982-01-01

404

Preliminary survey report: control technology for brake lining at Northwest Local School District, Cincinnati, Ohio  

Microsoft Academic Search

A walk-through survey of control technology for reducing asbestos exposure during maintenance and repair of vehicular brakes was conducted at Northwest Local School District, Cincinnati, Ohio in January, 1986. The primary method for controlling and collecting dust during brake servicing was a wet-washing technique and good work practices, ensuring that exposure to hazardous physical or chemical agents was reduced or

T. C. Cooper; J. D. McGlothlin; F. W. Godbey; J. W. Sheehy; D. M. OBrien

1986-01-01

405

Situation Assessment of an Autonomous Emergency Brake for Arbitrary Vehicle-to-Vehicle Collision Scenarios  

Microsoft Academic Search

The autonomous emergency brake (AEB) is an active safety function for vehicles which aims to reduce the severity of a collision. An AEB performs a full brake when an accident becomes unavoidable. Even if this system cannot, in general, avoid the accident, it reduces the energy of the crash impact and is therefore referred to as a collision mitigation system.

Nico Kaempchen; Bruno Schiele; Klaus Dietmayer

2009-01-01

406

Calibration of Resolver Sensors in Electromechanical Braking Systems: A Modified Recursive Weighted Least-Squares Approach  

Microsoft Academic Search

Resolver sensors are utilized as absolute position transducers to control the position and speed of actuators in many industrial applications. The accuracy and convergence of the position and speed measurements provided by resolvers in electromechanical braking system (EMB) designs directly contribute to the braking performance and vehicle safety. In practice, the dc drifts, amplitudes, and phase shift of the resolver

Reza Hoseinnezhad; Alireza Bab-Hadiashar; Peter Harding

2007-01-01

407

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

Federal Register 2010, 2011, 2012, 2013

...FRA-2013-0064] Petition for Modification of Single Car Air Brake Test Procedures In accordance...per 49 CFR 232.307 to modify the single car air brake test procedures located in AAR...System Tests for Freight Equipment-- Single Car Test, and required pursuant to 49 CFR...

2013-07-23

408

76 FR 34801 - Petition for Modification of Single Car Air Brake Test Procedures  

Federal Register 2010, 2011, 2012, 2013

...FRA-2010-0174] Petition for Modification of Single Car Air Brake Test Procedures In accordance...FRA) grant a modification of the single car air brake test procedures as prescribed...FRA-2010-0174. PATH operates a fleet of 25 flat cars in consist with revenue cars utilized...

2011-06-14

409

A Test of the Tau-Dot Hypothesis of Braking Control in the Real World  

ERIC Educational Resources Information Center

A controlled experiment used instrumented vehicles in a real-world driving task to compare D. N. Lee's (1976) tau-dot hypothesis of braking control with an alternative based on the direct estimation and control of ideal deceleration (T. Yates, M. Harris, & P. Rock, 2004). Drivers braked to stop as closely as possible to a visual target from…

Rock, Paul B.; Harris, Mike G.; Yates, Tim

2006-01-01

410

Chemical and microstructural changes induced by friction and wear of brakes  

Microsoft Academic Search

The chemical and microstructural changes occurring during braking simulation tests at the surface of a conventional brake pad material were investigated mainly by scanning and transmission electron microscopy and surface analytical techniques. It can be shown that patches of a third body material develop, comprising a compositional mix of all constituents of the pad and iron oxides from the disk.

W. Österle; M. Griepentrog; Th. Gross; I. Urban

2001-01-01

411

A STUDY ON THE SQUEAL OF A DRUM BRAKE WHICH HAS SHOES OF NON-UNIFORM CROSS-SECTION  

Microsoft Academic Search

A stability analysis of a drum brake, which has shoes of non-uniform cross-section, is performed to find a simple and effective method of reducing the squeal of the drum brake by partially changing the shapes of the shoes. The squeal is considered as a noise induced by the self-excited vibration of the drum brake which makes the brake unstable. Shoes

J. M. LEE; S. W. YOO; J. H. KIM; C. G. AHN

2001-01-01

412

a Study on the Squeal of a Drum Brake which has Shoes of Non-Uniform Cross-Section  

Microsoft Academic Search

A stability analysis of a drum brake, which has shoes of non-uniform cross-section, is performed to find a simple and effective method of reducing the squeal of the drum brake by partially changing the shapes of the shoes. The squeal is considered as a noise induced by the self-excited vibration of the drum brake which makes the brake unstable. Shoes

J. M. Lee; S. W. Yoo; J. H. Kim; C. G. Ahn

2001-01-01

413

On the dry and wet sliding performance of potentially new frictional brake pad materials for automotive industry  

Microsoft Academic Search

In this work, dry and wet continuous sliding performances of newly developed four different non-commercial frictional brake pad materials (NF1, NF2, NF4, and NF5) were evaluated and compared with other two chosen commercial brake pad materials (CMA and CMB) using a small-scale tribo-tester of pad-on-disc type.Results showed that under dry continuous braking, friction coefficients for all non-commercial brake pad materials

N. S. M. EL-Tayeb; K. W. Liew

2009-01-01

414

Anti-lock brake system control for buses based on fuzzy logic and a sliding-mode observer  

Microsoft Academic Search

In this paper, an anti-lock brake system (ABS) for commercial buses is proposed based on a fuzzy-logic controller and a sliding-mode\\u000a observer of the vehicle speed. The brake controller generates pulse width modulated (PWM) control inputs to the solenoid valve\\u000a of each brake, as a function of the estimated wheel slip ratio. PWM control inputs at the brakes significantly reduce

Jong Hyeon Park; Dong Hee Kim; Yong Ju Kim

2001-01-01

415

Hydraulic charcterization of carbonatic rock  

Microsoft Academic Search

The hydraulic conductivity, K(theta), and the water retention, theta(h), are needed to predict the flow of water and solute transport in unsaturated porous media. During recent decades methods have been developed to determine these hydraulic properties for rock. We have developed a methodology, based on Wind's evaporation method for soils, to measure in the laboratory the water retention and hydraulic

M. C. Caputo; A. Basile; R. de Mascellis; J. R. Nimmo; M. Vurro; N. Walsh

2003-01-01

416

75: Determining Soil Hydraulic Properties  

Microsoft Academic Search

Hydraulic properties are required for modeling water and solute transport in unsaturated soils. The bottleneck for the successful application of numerical simulation models lays usually in their parameter estimation requirements. Methods to determine hydraulic properties can be classified into indirect and direct approaches. Indirect methods encompass the estimation of hydraulic properties by pedotransfer functions from more easily measured soil properties,

WOLFGANG DURNER; KAI LIPSIUS

2005-01-01

417

Computer simulation of hydraulic fractures  

Microsoft Academic Search

We provide a brief historical background of the development of hydraulic fracturing models for use in the petroleum and other industries. We discuss scaling laws and the propagation regimes that control the growth of hydraulic fractures from the laboratory to the field scale. We introduce the mathematical equations and boundary conditions that govern the hydraulic fracturing process, and discuss numerical

J. Adachi; E. Siebrits; A. Peirce; J. Desroches

2007-01-01

418

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

NASA Astrophysics Data System (ADS)

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

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

2012-06-01

419

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

SciTech Connect

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.

Blau, PJ

2001-10-22

420

Design of permanent magnet eddy current brake for a small scaled electromagnetic launch model  

NASA Astrophysics Data System (ADS)

A variable pole-pitch double-sided permanent magnet (PM) linear eddy current brake (LECB) is proposed for a small scaled electromagnetic launch model. A two-dimensional (2D) analytical steady state model is presented for the double-sided PM-LECB, and the expression for the braking force is derived. Based on the analytical model, the material and eddy current skin effect of the conducting plate are analyzed. Moreover, a variable pole-pitch double-sided PM-LECB is proposed for the effective braking of the moving plate. In addition, the braking force is predicted by finite element (FE) analysis, and the simulated results are in good agreement with the analytical model. Finally, a prototype is presented to test the braking profile for validation of the proposed design.

Zhou, Shigui; Yu, Haitao; Hu, Minqiang; Huang, Lei

2012-04-01

421

In-depth survey report: evaluation of brake-drum service controls at Cincinnati Bell Maintenance Facility, Fairfax, Ohio  

Microsoft Academic Search

The effectiveness of vacuum units (Nilfisk Asbestos-Clene System) equipped with high efficiency particulate air filters in limiting exposure to asbestos during the servicing of automotive brakes was evaluated. Brake servicing of seven vehicles at the Cincinnati Bell Fairfax Garage was studied. Phase contrast microscope (PCM) analyses of personal air samples, collected for the duration of a single brake job or

J. W. Sheehy; W. F. Todd; T. C. Cooper; H. D. Van Wagenen

1987-01-01

422

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

PubMed

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 (p<0.05). By performing clustering analysis on two kinematic parameters, two different strategies of the volunteers were identified. They were not related to the braking scenarios. A relation of the clusters with the initial posture represented by the elbow angle was revealed (p<0.05). It is concluded that autonomous 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. PMID:23036398

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

2011-08-26

423

Mesothelioma among brake mechanics: an expanded analysis of a case-control study.  

PubMed

The U.S. Environmental Protection Agency has begun discussions to consider its assessment of asbestos toxicity related to mineral form and fiber size. Brake workers are typically exposed to short chrysotile fibers. To explore the mesothelioma risk among brake workers, considering other occupational exposures to asbestos, data from a study that was published previously were obtained and the analysis was extended. The National Cancer Institute provided data from a case-control study of mesothelioma. Because many participants with a history of brake work also had employment in other asbestos-related occupations, mesothelioma cases and controls were compared for a history of brake work, controlling for employment in eight occupations with potential asbestos exposure. A stratified analysis was also performed excluding those with any of the eight occupations. Possible interactions between brake work and other occupational exposures related to risk of mesothelioma were also examined. The odds ratio (OR) for employment in brake installation or repair was 0.71 (95% CI: 0.30-1.60) when controlled for insulation or shipbuilding. When a history of employment in any of the eight occupations with potential asbestos exposure was controlled, the OR was 0.82 (95% CI: 0.36-1.80). ORs did not increase with increasing duration of brake work. Exclusion of those with any of the eight exposures resulted in an OR of 0.62 (95% CI: 0.01-4.71) for occupational brake work. There was no evidence of an interaction between brake work and other occupational exposures. These latter analyses were based on small numbers of exposed cases. The results are consistent with the existing literature indicating that brake work does not increase the risk of mesothelioma and adds to the evidence that fiber type and size are important determinants of mesothelioma risk. PMID:15209929

Hessel, Patrick A; Teta, M Jane; Goodman, Michael; Lau, Edmund

2004-06-01

424

Differential Rotation in Neutron Stars: Magnetic Braking and Viscous Damping  

NASA Astrophysics Data System (ADS)

Differentially 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 gas has no viscosity and the star resides in an exterior vacuum. We treat numerically cases in which the gas has internal viscosity and the star is embedded in an exterior, low-density, conducting medium. Our evolution calculations are presented to stimulate more realistic MHD simulations in full 3+1 general relativity. They serve to identify some of the key physical and numerical parameters, scaling behavior, and competing timescales that characterize this important process.

Shapiro, Stuart L.

2000-11-01

425

Wind turbine trailing-edge aerodynamic brake design  

SciTech Connect

This report describes the design of a centrifugally actuated aerodynamic-overspeed device for a horizontal-axis wind turbine. The device will meet the following criteria; (1) It will be effective for airfoil angles of attack 0{degrees} to 45{degrees}. (2) It will be stowed inside the blade profile prior to deployment. (3) It will be capable of offsetting the positive torque produced by the overall blade. (4) Hinge moments will be minimized to lower actuator loads and cost. (5) It will be evaluated as a potential power modulating active rotor-control system. A literature review of aerodynamic braking devices was conducted. Information from the literature review was used to conceptualize the most effective devices for subsequent testing and design. Wind-tunnel test data for several braking devices are presented in this report. Using the data for the most promising configuration, a preliminary design was developed for a MICON 65/13 wind turbine with Phoenix 7.9-m rotor blades.

Quandt, G.

1996-01-01

426

Hydraulic manipulator research at ORNL  

SciTech Connect

Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL`s flexible/prismatic test stand.

Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States); Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States)

1997-03-01

427

Hydraulic waste energy recovery  

SciTech Connect

Water distribution systems are typically a municipality's largest consumer of energy and greatest expense. The water distribution network has varying pressure requirements due to the age of the pipeline and topographical differences. Certain circumstances require installation of pressure reducing devices in the pipeline to lower the water pressure in the system. The consequence of this action is that the hydraulic energy supplied by the high lift or booster pumps is wasted in the process of reducing the pressure. A possible solution to capture the waste hydraulic energy is to install an in-line electricity generating turbine. Energy recovery using in-line turbine systems is an emerging technology. Due to the lack of technical and other relevant information on in-line turbine system installations, questions of constructability and legal issues over the power service contract have yet to be answered. This study seeks to resolve these questions and document the findings so that other communities may utilize this information. 10 figs.

Lederer, C.C.; Thomas, A.H.; McGuire, J.L. (Detroit Buildings and Safety Engineering Dept., MI (USA))

1990-12-01

428

Hydraulic Arm Challenge  

NSDL National Science Digital Library

Students design and build a mechanical arm that lifts and moves an empty 12-ounce soda can using hydraulics for power. Small design teams (1-2 students) design and build a single axis for use in the completed mechanical arm. One team designs and builds the grasping hand, another team the lifting arm, and a third team the rotation base. The three design groups must work to communicate effectively through written and verbal communication and sketches.

The Tufts Center For Engineering Educational Outreach

429

Modeling of automotive drum brakes for squeal and parameter sensitivity analysis  

NASA Astrophysics Data System (ADS)

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.

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

2006-01-01

430

Frictional and heat resistance characteristics of coconut husk particle filled automotive brake pad  

NASA Astrophysics Data System (ADS)

The objective of this study was to determine the friction and heat resistance characteristics of automotive brake pad composed with different sizes and percentages of coconut husk particle. The materials used were phenolic resin (phenol formaldehyde) as binder, copper, graphite and brass as friction producer/modifiers, magnesium oxide as abrasive material, steel and barium sulfate as reinforcement while coconut husk particle as filler. To obtain particle, the coconut husk was ground and dried to 3% moisture content. Then the coconut husk particle was screened using 80 mesh (to obtain coarse dust) and 100 mesh (to obtain fine dust). Different percentages of particle, such as 10 and 30% were used in the mixture of brake pad materials. Then the mixture was hot-pressed to produce brake pad. Chase machine was used to determine the friction coefficient in friction resistance testing, while thermogravimetric analyzer (TGA) machine was used to determine the heat decomposition values in heat resistance testing. Results showed that brake pad with 100 mesh and 10% composition of coconut husk particle showed the highest friction coefficient. For heat resistance, brake pad with 100 mesh and 30% composition of coconut husk dust showed the highest decomposition temperature, due to the high percentage of coconut husk particle in the composition, thus increased the thermal stability. As a comparison, brake pad composed with coconut husk particle showed better heat resistance results than commercial brake pad.

Bahari, Shahril Anuar; Chik, Mohd Syahrizul; Kassim, Masitah Abu; Som Said, Che Mohamad; Misnon, Mohd Iqbal; Mohamed, Zulkifli; Othman, Eliasidi Abu

2012-06-01

431

Frictional behavior of automotive brake materials under wet and dry conditions  

SciTech Connect

The purpose of this effort was to develop an improved understanding of the relationship between the structure and frictional behavior of materials in the disc brake/rotor interface with a view toward improving the performance of automotive disc brakes. The three tasks involved in this Cooperative Research and Development Agreement (CRADA) were as follows: Task 1. Investigation of Brake Pads and Rotors. Characterize surface features of worn brake pads and rotors, with special attention to the transfer film which forms on them during operation. Ford to supply specimens for examination and other supporting information. Task 2. Effects of Atmosphere and Repeated Applications on Brake Material Friction. Conduct pin-on-disk friction tests at ORNL under controlled moisture levels to determine effects of relative humidity on frictional behavior of brake pad and rotor materials. Conduct limited tests on the characteristics of friction under application of repeated contacts. Task 3. Comparison of Dynamometer Tests with Laboratory Friction Tests. Compare ORNL friction data with Ford dynamometer test data to establish the degree to which the simple bench tests can be useful in helping to understand frictional behavior in full-scale brake component tests. This final report summarizes work performed under this CRADA.

Blau, P.J.; Martin, R.L. [Oak Ridge National Lab., TN (United States); Weintraub, M.H.; Jang, Ho; Donlon, W. [Ford Motor Co., Dearborn, MI (United States)

1996-12-15

432

Exposure to asbestos during brake maintenance of automotive vehicles by different methods  

SciTech Connect

Asbestos concentrations were measured during the different operations of brake maintenance of passenger cars, trucks and buses in 24 Finnish workplaces. The estimated average asbestos exposure during the workday (8-hr time-weighted average) was 0.1-0.2 fibers/cm/sup 3/ during brake repair of trucks or buses, and under 0.05 f/cm/sup 3/ during repair of passenger car brakes when the background concentration was not included in the calculations. The background concentration was estimated to be less than 0.1 f/cm/sup 3/. During brake maintenance of buses and trucks, heavy exposure, 0.3-125 (mean 56) f/cm/sup 3/, was observed during machine grinding of new brake linings if local exhaust was not in use. Other short-term operations during which the concentration exceeded 1 f/cm/sup 3/ were the cleaning of brakes with a brush, wet cloth or compressed air jet. During brake servicing of passenger cars, the concentration of asbestos exceeded 1 f/cm/sup 3/ only during compressed air blowing without local exhaust. The different methods of decreasing the exposure and the risk of asbestos-related diseases among car mechanics are discussed.

Kauppinen, T.; Korhonen, K.

1987-05-01

433

Airborne asbestos concentration from brake changing does not exceed permissible exposure limit.  

PubMed

The use in the past, and to a lesser extent today, of chrysotile asbestos in automobile brake systems causes health concerns among professional mechanics. Therefore, we conducted four separate tests in order to evaluate an auto mechanic's exposure to airborne asbestos fibers while performing routine brake maintenance. Four nearly identical automobiles from 1960s having four wheel drum brakes were used. Each automobile was fitted with new replacement asbestos-containing brake shoes and then driven over a predetermined public road course for about 2253 km. Then, each car was separately brought into a repair facility; the brakes removed and replaced with new asbestos-containing shoes. The test conditions, methods, and tools were as commonly used during the 1960s. The mechanic was experienced in brake maintenance, having worked in the automobile repair profession beginning in the 1960s. Effects of three independent variables, e.g., filing, sanding, and arc grinding of the replacement brake shoe elements, were tested. Personal and area air samples were collected and analyzed for the presence of fibers, asbestos fibers, total dust, and respirable dust. The results indicated a presence in the air of only chrysotile asbestos and an absence of other types of asbestos. Airborne chrysotile fiber exposures for each test remained below currently applicable limit of 0.1 fiber/ml (eight-hour time-weighted average). PMID:12878055

Blake, Charles L; Van Orden, Drew R; Banasik, Marek; Harbison, Raymond D

2003-08-01

434

Exposure to asbestos during brake maintenance of automotive vehicles by different methods.  

PubMed

Asbestos concentrations were measured during the different operations of brake maintenance of passenger cars, trucks and buses in 24 Finnish workplaces. The estimated average asbestos exposure during the workday (8-hr time-weighted average) was 0.1-0.2 fibers/cm3 during brake repair of trucks or buses, and under 0.05 f/cm3 during repair of passenger car brakes when the background concentration was not included in the calculations. The background concentration was estimated to be less than 0.1 f/cm3. During brake maintenance of buses and trucks, heavy exposure, 0.3-125 (mean 56) f/cm3, was observed during machine grinding of new brake linings if local exhaust was not in use. Other short-term operations during which the concentration exceeded 1 f/cm3 were the cleaning of brakes with a brush, wet cloth or compressed air jet. During brake servicing of passenger cars, the concentration of asbestos exceeded 1 f/cm3 only during compressed air blowing without local exhaust. The different methods of decreasing the exposure and the risk of asbestos-related diseases among car mechanics are discussed. PMID:3591672

Kauppinen, T; Korhonen, K

1987-05-01

435

Preliminary survey report: control technology for brake lining at Northwest Local School District, Cincinnati, Ohio  

SciTech Connect

A walk-through survey of control technology for reducing asbestos exposure during maintenance and repair of vehicular brakes was conducted at Northwest Local School District, Cincinnati, Ohio in January, 1986. The primary method for controlling and collecting dust during brake servicing was a wet-washing technique and good work practices, ensuring that exposure to hazardous physical or chemical agents was reduced or eliminated. Also available was an enclosed-type brake assembly cleaner designed to be connected to the shop air and a vacuum system. The brake assembly cleaner did not have a viewing port to examine the area being cleaned. The operator had to remove the unit to inspect the cleaned area potentially exposing himself to any dust remaining on the brake shoes or hub. The unit itself was a potential dust source as it was designed to fit 16-inch wheels and did not form a tight seal on the smaller 15-inch wheels of the newer buses. The authors conclude that the wet wash technique is an excellent method for controlling asbestos emissions during brake maintenance. The vacuum brake-assembly cleaner is inadequate and potentially hazardous. An in-depth survey of the wet technique is recommended.

Cooper, T.C.; McGlothlin, J.D.; Godbey, F.W.; Sheehy, J.W.; O'Brien, D.M.

1986-05-01

436

Mechanical-hydraulic integration modeling and simulation of hydraulic support  

Microsoft Academic Search

Based on Virtual Prototyping Technology, the co-simulation technology for mining machinery has been studied and applied. Hydraulic support is used as an example and the whole virtual prototype model of hydraulic ramming device was established, the co-simulation between mechanical system and control system is realized by means of software ADAMS and EASY5. The response of hydraulic support's mechanical system and

Lirong Wan; Xiaowang Wu; Chenglong Wang; Xin Zhang

2010-01-01

437

The unbalanced signal measuring of automotive brake drum  

NASA Astrophysics Data System (ADS)

For the purpose of the research and development of automatic balancing system by mass removing, the dissertation deals with the measuring method of the unbalance signal, the design the automatic balance equipment and the software. This paper emphases the testing system of the balancer of automotive brake drum. The paper designs the band-pass filter product with favorable automatic follow of electronic product, and with favorable automatic follow capability, filtration effect and stability. The system of automatic balancing system by mass removing based on virtual instrument is designed in this paper. A lab system has been constructed. The results of contrast experiments indicate the notable effect of 1-plane automatic balance and the high precision of dynamic balance, and demonstrate the application value of the system.

Wang, Xiao-Dong; Ye, Sheng-Hua; Zhang, Bang-Cheng

2005-04-01

438

A laboratory activity on the eddy current brake  

NASA Astrophysics Data System (ADS)

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.

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

2012-05-01

439

TOR-driven aging: speeding car without brakes.  

PubMed

This article discusses that the traditional analogy of an aging organism with a rusting (albeit self-repairing) car is misleading. The true analogy is a speeding car that enters a low-speed zone and damages itself because it does not and cannot slow down. For such a car without brakes (and actually without a driver), aging from rusting never occurs. Using simple analogies (although turning gerontology upside down), this article discusses the origin of aging, how overactivation of the mTOR (Target of Rapamycin) pathway causes aging, why aging causes damage (organ damage) not damage causes aging, the link between aging and age-related diseases, slow aging versus aging tolerance and suppression of aging with rapamycin. PMID:19923900

Blagosklonny, Mikhail V

2009-12-09

440

Development of an MR-brake-based haptic device  

NASA Astrophysics Data System (ADS)

This paper describes the design, testing and modelling of a magneto-rheological (MR) fluid brake as well as its application in a haptic device. The MR device, in disc shape, is composed of a rotary shaft and plate, an electromagnetic coil, MR fluids, and casings. The working principle of the actuator is discussed and the transmitted torque equation employed by using the Bingham plastic model. The optimal dimensions of the actuator were obtained by finite-element analysis using the COSMOSEMS package. Following manufacturing and fabrication of the actuator prototype, the steady-state performance of the MR actuator was measured using a force gauge. The experimental results show that the actuator exhibits hysteresis behaviour. A sub-hysteresis model was then proposed and the model parameters were identified. Example applications of this actuator in virtual reality are demonstrated.

Liu, B.; Li, W. H.; Kosasih, P. B.; Zhang, X. Z.

2006-12-01

441

Magnetic braking and the evolution of cataclysmic binaries  

NASA Astrophysics Data System (ADS)

The authors study the evolution and the period distribution of cataclysmic variables using a magnetic braking law proposed recently by Mestel & Spruit (1987). The application of this law gives a predicted period distribution that matches the observed one. The authors also show that the observed accumulation of AM Her systems with periods in the range 114 - 115 min can be explained in terms of evolution, as a result of the adiabatic expansion of the secondary when accretion resumes at the end of the period gap provided that the masses of the white dwarfs in AM Her systems are in a restricted range. The authors examine finally the recent claim by Lamb & Melia (1987) that when the magnetic white dwarf synchronizes with the orbit, the system detaches, and enters a prolonged gap. They show that the proposed mechanism does not work, and that synchronization has a relatively small effect on the evolution of these systems.

Hameury, J. M.; King, A. R.; Lasota, J. P.; Ritter, H.

1988-03-01

442

Fracture Analysis and Material Improvement of Brake Discs  

NASA Astrophysics Data System (ADS)

Using a steel material for forging, development of new discs for the next Shinkansen had been started. However, a fracture in a forged disc occurred in a durability test. Subsequently, from the viewpoint of higher fracture toughness, material improvement to an extent sufficient to withstand such a fracture due to tensile residual stress accumulation became the goal of further development. Among the candidate materials, modified AISI 4330 was selected and evaluated in laboratory and field tests. Following the subsequent durability test in the field, modification for bolt sticking and forging formability was conducted. This new brake disc, which proved to be satisfactory for Shinkansen vehicles, is capable of running at high speeds of more than 270km/h and therefore suitable for current vehicles such as the Nozomi and Tsubasa.

Sakamoto, Haruo; Hirakawa, Kenji

443

Self-excited brake noise investigation using the technique of classical holographic interferometry  

NASA Astrophysics Data System (ADS)

The development of a systematic, whole body, visual recording process and its application to the study of disc brake noise and its recent adaptation to investigate drum brake noise is discussed. It is demonstrated that amplitude and vibration phase information my be obtained using classical double pulsed holographic techniques. Additionally it is demonstrated that details of a moving mode of vibration may be obtained in a rotating body. The application to drum brake noise show how low frequency noise (1 kHz) is related to backplate excitation whereas higher frequency noise (6 kHz) relates to drum excitation.

Fieldhouse, J. D.; Newcomb, T. P.

1994-09-01

444

Vibration control of an artificial muscle manipulator with a magnetorheological fluid brake  

NASA Astrophysics Data System (ADS)

Recently, proposed applications of robots require them to contact human safely. Therefore, we focus on pneumatic rubber artificial muscle. This actuator is flexible, light, and has high-power density. However, because the artificial muscle is flexible, it vibrates when there is a high load. Therefore, we paid attention to the magnetorheological (MR) fluid. We propose a control method of the MR brake considering energy of the manipulator system. By this control method, MR brake dissipates energy leading to vibration of the manipulator. In this paper, we calculated the energy and controlled the MR brake. And, we deliberated the proposal method by simulation using the dynamic model of the manipulator, and experiment.

Tomori, H.; Midorikawa, Y.; Nakamura, T.

2013-02-01

445

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

SciTech Connect

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.

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

2007-01-01

446

Dual-purpose hydraulic fluid  

US Patent & Trademark Office Database

A synthetic dual-purpose fluid for use as a hydraulic fluid and in metal cutting operations, particularly where hydraulic fluid leakage cannot be tolerated in hydraulically operated machines designed for metal cutting purposes. The fluid contains in combination 50-70% of an alkylene glycol, 10 to 25% of an alkanol amine, up to 10% boric acid, and 2 to 25% of a phosphate-modified condensation product of a fatty acid and a dialkanolamine.

1980-06-24

447

Fluid Power/Basic Hydraulics. Instructor's Guide.  

ERIC Educational Resources Information Center

|This guide is designed to assist industrial vocational instructors in teaching a course on fluid power and basic hydraulics. Covered in the unit on the basics of fluid power and hydraulics are the following topics: the fundamentals of fluid power and hydraulics, basic hydraulic circuits, and servicing a hydraulic jack. The second unit, consisting…

Stanbery, Richard

448

110. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

110. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (109), LSB (BLDG. 770) ACCUMULATOR FOR MAST RETRACTION ON LEFT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

449

128. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

128. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751). PUMP ON RIGHT; ACCUMULATOR FOR MAST RETRACTION ON LEFT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

450

Power hydraulics - switched mode control of hydraulic actuation  

Microsoft Academic Search

This paper is concerned with the application of switching technology to hydraulic actuation. Over the last 50 years with advances in power electronics, faster and faster static switches have been developed and applied to the control of motors. Hydraulic technology evolved in the opposite direction: switching control was not considered, and more and more accurate proportional flow\\/pressure control devices (servovalves

Emanuele Guglielmino; Claudio Semini; Helmut Kogler; Rudolf Scheidl; Darwin G. Caldwell

2010-01-01

451

Development of Car/Trailer Handling and Braking Standards. Volume I: Executive Summary.  

National Technical Information Service (NTIS)

This report summarizes the development of handling and braking performance requirements for passenger cars towing trailers. These requirements are based on the results of over 2000 combination-vehicle tests with eight trailers and three rear wheel drive t...

R. H. Klein H. T. Szostak

1979-01-01

452

Analysis of the Crash Experience of Vehicles Equipped with Antilock Braking Systems (ABS).  

National Technical Information Service (NTIS)

NHTSA's National Center for Statistics and Analysis has recently completed an intial analysis of the crash experience of passenger cars (PCs) and light trucks and vans (LTVs) equipped with antilock braking systems (ABS). Separate analyses were conducted f...

D. M. Johnson

1995-01-01

453

Analysis of Braking Behavior of Train Drivers to Detect Unusual Driving  

NASA Astrophysics Data System (ADS)

The safety devices for train systems are activated in emergency situations when a risk becomes obvious, and the emergency brake is applied. If such systems are faulty, the drivers' operating errors may cause immediate accidents. So it is necessary to evaluate potential risks by detecting improper driving behavior before overt risks appear. This study analyzes the driving behavior of train drivers using a train-driving simulator. We focus on braking behavior when approaching a station. Two methods for detecting unusual braking operation are examined by giving drivers mental calculation problems as a mental workload. The first is a method monitoring the driver's brake handle operation, and the second is a method measuring vehicle deceleration. These methods make it possible to detect unusual driving.

Marumo, Yoshitaka; Tsunashima, Hitoshi; Kojima, Takashi; Hasegawa, Yasushi

454

A Fuzzy Logic Controlled Braking Resistor Scheme for Damping Shaft Torsional Oscillations  

NASA Astrophysics Data System (ADS)

This paper presents a fuzzy logic switching for the thyristor controlled braking resistor to damp turbine-generator shaft torsional oscillations. Following a major disturbance in electric power system, variable rotor speed of the generator is measured, and then the current through the braking resistor is controlled by the firing-angle of the thyristor switch which is controlled by the fuzzy logic. Thus the braking resistor controls the accelerating power in generators and damps the shaft torsional oscillations. The effects of the fault occurring time on turbine shaft torsional torques have also been investigated. Simulations are performed by using EMTP (Electro-Magnetic Transients Program). Through the simulation results of various multi-phase faults in a single machine connected to an infinite bus system, the effectiveness of the proposed fuzzy logic controlled braking resistor in damping shaft torsional oscillations is demonstrated.

Ali, Mohd. Hasan; Mikami, Takumi; Murata, Toshiaki; Tamura, Junji

455

MERCURY EMISSIONS FROM BRAKE WEAR ASSOCIATED WITH ON-ROAD VEHICLES  

EPA Science Inventory

This paper will focus on brake wear emissions of mercury and trace metals collected from 16 in-use light-duty vehicles (14 gasoline and 2 diesel) on a chassis dynamometer over the course of urban drive cycles....

456

49 CFR 236.502 - Automatic brake application, initiation by restrictive block conditions stopping distance in...  

Code of Federal Regulations, 2012 CFR

...restrictive block conditions stopping distance in advance. 236.502 Section 236...restrictive block conditions stopping distance in advance. An automatic train-stop...automatic brake application at least stopping distance from the entrance to a block,...

2012-10-01

457

49 CFR 236.502 - Automatic brake application, initiation by restrictive block conditions stopping distance in...  

Code of Federal Regulations, 2011 CFR

...restrictive block conditions stopping distance in advance. 236.502 Section 236...restrictive block conditions stopping distance in advance. An automatic train-stop...automatic brake application at least stopping distance from the entrance to a block,...

2011-10-01

458

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

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Standard No. 135; Light vehicle brake systems. 571.135 Section 571...DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE SAFETY STANDARDS Federal Motor Vehicle Safety Standards § 571.135 Standard...

2010-10-01

459

Preliminary Survey Report: Control Technology for Brake Lining at Northwest Local School District, Cincinnati, Ohio.  

National Technical Information Service (NTIS)

A walk through survey of control technology for reducing asbestos (1332214) exposure during maintenance and repair of vehicular brakes was conducted at Northwest Local School District (SIC-3211), Cincinnati, Ohio in January, 1986. The primary method for c...

T. C. Cooper J. D. McGlothlin F. W. Godbey J. W. Sheehy D. M. O'Brien

1986-01-01

460

Applications of magnetorheological brakes in manual control of lifting devices and manipulators  

NASA Astrophysics Data System (ADS)

The article is aimed to design and testing of joystick with force feedback used in direct, human control of lifting device. The paper starts with the basic description of designed and tested by us MR rotary brake. Some initial laboratory investigations results of such brakes are presented. The usage of MR brakes in 2 axis joystick is proposed. Such, built by as joystick, is described. It was used as Human-Machine Interface in active control of lifting device. The designed and built 2 axis manipulator with electrohydraulic drive is described. In the paper, the based on PC with input/output card, control system of mentioned above joystick with MR brake and manipulator is described. Finally the control algorithm is proposed.

Chciuk, M.; Milecki, A.; Myszkowski, A.

2009-02-01

461

49 CFR 232.103 - General requirements for all train brake systems.  

Code of Federal Regulations, 2011 CFR

...instruction required in this paragraph shall take into account winter weather conditions as they relate to throttle position and reverser...Locomotives PSI (1) Minimum brake pipe air pressure: Road Service 90 Switch Service 60 (2) Minimum...

2011-10-01

462

Determining the frequency of asbestos use in automotive brakes from a fleet of on-road California vehicles.  

PubMed

Asbestos is a known human carcinogen, and recent regulation in California limits asbestiform fibers in brakes to trace levels beginning in 2014, although there is no corresponding federal requirement. In order to gauge the current prevalence of asbestos use in automotive brake applications, the California Air Resources Board tested brake linings from 137 light- and medium-duty vehicles and 54 heavy-duty vehicles. Only about 3% of the light- and medium-duty vehicle brake linings contained chrysotile asbestos. All of those brake linings were drum-type shoes, which are generally being phased out. No asbestos was found in low mileage vehicles presumed to have their original stock linings from the vehicle manufacturer. Additionally, no asbestos was found in the heavy-duty vehicle brake shoe linings sampled. Given the small percentage of vehicle brake linings with asbestos observed, it appears that the prior federal ban that was subsequently overturned, in combination with a threat of litigation, has reduced asbestos use in brake linings. However, our study was limited in scope and without a national ban, the current and future prevalence of asbestos in brakes is uncertain, suggesting the need for continued monitoring of materials released as toxic air contaminants in normal braking operations. PMID:22191788

De Vita, Joseph; Wall, Stephen; Wagner, Jeff; Wang, Zhong-Min; Rao, Leela E

2012-01-13

463

Dual hydraulic safety valve  

SciTech Connect

This patent describes a subsurface well safety valve for controlling the fluid flow through a well conduit and including a housing having a bore and a valve closure member moving between open and closed positions for controlling the fluid flow through the bore, a tubular member telescopically moving in the housing for controlling the movement of the valve closure member. The improvement in fluid actuating means for actuating the valve closure member comprising, a first piston and cylinder assembly in the housing adapted to be connected to a hydraulic control line, the first assembly connected to the tubular member, a second piston and cylinder assembly in the housing adapted to be connected to a hydraulic control line, the second assembly disconnected from the tubular member, and means for disconnecting the first assembly from the tubular member and connecting the second assembly to the tubular member. The method of operating a subsurface well safety valve for controlling the fluid flow through a well conduit in which the valve includes a housing having a bore and a valve closure member moving between open and closed positions for controlling the fluid flow through the bore.

Leismer, D.D.; Blizzard, W.A. Jr.

1989-06-13

464

Study on the stability of drum brake non-linear low frequency vibration model  

Microsoft Academic Search

A 5-DOF non-linear model is presented to simulate the vibration of a drum brake at low frequency in the course of applying\\u000a the brake. Analysis and calculation are carried out to illuminate that even when the friction coefficient is constant, the\\u000a vibration and instability can occur with the combination of some specific parameters. And the stable-unstable area on the\\u000a parameter

Minggang Zhou; Yong Wang; Qibai Huang

2007-01-01

465

Characteristics and morphology of wear particles from laboratory testing of disk brake materials  

Microsoft Academic Search

The geometrical characteristics and morphology of wear particles generated from brake materials are important for environmental and tribological reasons. Low- and high-speed, pin-on-disk friction and wear testing of a commercial truck brake pad material against cast iron was conducted in which wear debris was collected. The sliding speed was held constant either at 0.275 or at 5m\\/s, and the nominal

Mohsen Mosleh; Peter J Blau; Delia Dumitrescu

2004-01-01

466

Characteristics of wear particles produced during friction tests of conventional and unconventional disc brake materials  

Microsoft Academic Search

Recent attention to the improvement of line-haul truck brake effectiveness, to compensate for lowered aerodynamic drag and to increase road safety, has prompted the US Department of Energy to support several projects aimed at the development of lightweight, high-performance friction materials. Using a specially designed, sub-scale disc brake testing system, a series of experiments was conducted to study the friction,

Peter J. Blau; Harry M. Meyer

2003-01-01

467

Microstructure and tribological properties of advanced carbon\\/silicon carbide aircraft brake materials  

Microsoft Academic Search

The structural characteristics of carbon\\/silicon carbide (C\\/SiC) aircraft brake materials were studied by means of optical microscopy, SEM, XRD and TEM, and their frictional properties were investigated using a full-size aircraft wheel and brake assembly on a full-scale dynamometer. The materials were composed of layers of non-woven fiber cloth, short fiber web, and needle fibers. SiC and Si were mostly

Shangwu Fan; Litong Zhang; Yongdong Xu; Laifei Cheng; Guanglai Tian; Shaochang Ke; Fang Xu; Haiping Liu

2008-01-01

468

A through-process model of an A356 brake caliper for fatigue life prediction  

Microsoft Academic Search

The demand for low-cost, high strength-to-weight ratio components continues to drive the development of aluminum alloy castings\\u000a for new applications. The automotive brake caliper, which has traditionally been made from cast iron, is one such component\\u000a where aluminum alloys are being considered. The fatigue performance of the brake caliper is an important consideration in\\u000a evaluating new designs. The use of

D. M. Maijer; Y. X. Gao; P. D. Lee; T. C. Lindley; T. Fukui

2004-01-01

469

Antioxidative responses to arsenic in the arsenic-hyperaccumulator Chinese brake fern ( Pteris vittata L.)  

Microsoft Academic Search

This study measured antioxidative responses of Chinese brake fern (Pteris vittata L.) upon exposure to arsenic (As) of different concentrations. Chinese brake fern was grown in an artificially-contaminated soil containing 0 to 200 mg As kg?1 (Na2HAsO4) for 12 weeks in a greenhouse. Soil As concentrations at ?20 mg kg?1 enhanced plant growth, with 12–71% biomass increase compared to the

Xinde Cao; Lena Q. Ma; Cong Tu

2004-01-01

470

Target slip tracking using gain-scheduling for antilock braking systems  

Microsoft Academic Search

In this paper, a gain-scheduling scheme is proposed for optimal target slip tracking of an antilock braking system. The study is based on the fact that for certain road surface condition, the tire force characterization, i.e. the force-slip curve, is indeed varying with respect to different vehicle forward speed. The optimal slip at which the braking force achieves its maximum

Yong Liul; Jing Sun

1995-01-01

471

Effect of Carbon Nanotubes on Tribo-Performance of Brake Friction Materials  

NASA Astrophysics Data System (ADS)

Brake friction composites filled with multiwalled carbon nanotubes have been fabricated and evaluated for their tribo-performance. The tribological behavior of the frictional composites has been evaluated on a krauss testing machine as per the ECE regulations. The friction performance (?P), frictions fade (?F) and friction recovery (?R) gets enhanced with the addition of carbon nanotubes. The wear performance and brake pad thickness loss of the composites decreased with the increase in carbon nanotubes.

Singh, Tej; Patnaik, Amar; Satapathy, Bhabani K.

2011-12-01

472

Deconstructing a state-of-the-art review of the asbestos brake industry.  

PubMed

State of the art is a legal concept that describes what was known as knowable by experts including manufacturer's state of knowledge about the potential hazards of their product(s) at a point in time. In 2004, Paustenbach et al. published a state-of-the-art review that describes the development of knowledge about asbestos hazards to brake mechanics performing asbestos brake installation and maintenance. Paustenbach et al.'s review, however, omits important pieces of corporate knowledge, dismisses several historical scientific conclusions and ignores the way experts have applied the results of scientific research to protect workers and consumers handling asbestos brakes. By taking their state-of-the-art review out of the legal liability context, Paustenbach et al. create a misleading version of events that fails to properly address the question of what asbestos brake manufacturers knew or should have known about the potential hazards of their brakes to mechanics over time. Without proper presentation of this information, judges and juries cannot adequately assess whether these companies had a duty to warn or take other action to prevent injury to those exposed to their asbestos brakes. PMID:22202589

Egilman, David Steven; Ardolino, Emily Laura; Howe, Samantha; Bird, Tess

2011-01-01

473

Dancers with patellar tendinopathy exhibit higher vertical and braking ground reaction forces during landing.  

PubMed

Dancers are exposed to the effects of repetitive jumping and leaping as are other athletes that tend to develop patellar tendinopathy. Greater vertical ground reaction forces occur during landing from a dance leap than during takeoff and during other common athletic activities. The purposes of this study were: (1) to compare the landing ground reaction force profiles of participants with and without clinically diagnosed patellar tendinopathy, and (2) to determine the strength of the relationship between landing angle, and braking impulse. Eighteen elite pre-professional dancers (12 healthy, 6 with patellar tendinopathy; both groups 50% male) performed sauts de chat for kinetic and kinematic analysis. Dancers with patellar tendinopathy demonstrated greater peak vertical ground reaction force and impulse (36% and 15% greater, respectively). Dancers with patellar tendinopathy demonstrated greater peak braking ground reaction force and impulse (82% and 126% greater, respectively). Landing angle explained 67% of the braking impulse. Dancers with patellar tendinopathy exhibited greater vertical and braking impulses than healthy dancers. Braking impulse was strongly correlated with landing angle. While there was no difference between groups in landing angle, dancers with patellar tendinopathy exhibited greater braking impulse than their non-tendinopathic counterparts, even at similar landing angles. PMID:22758398

Fietzer, Abbigail Lynn; Chang, Yu-Jen; Kulig, Kornelia

2012-07-04

474

Vehicle speed affects both pre-skid braking kinematics and average tire/roadway friction.  

PubMed

Vehicles decelerate between brake application and skid onset. To better estimate a vehicle's speed and position at brake application, we investigated how vehicle deceleration varied with initial speed during both the pre-skid and skidding intervals on dry asphalt. Skid-to-stop tests were performed from four initial speeds (20, 40, 60, and 80 km/h) using three different grades of tire (economy, touring, and performance) on a single vehicle and a single road surface. Average skidding friction was found to vary with initial speed and tire type. The post-brake/pre-skid speed loss, elapsed time, distance travelled, and effective friction were found to vary with initial speed. Based on these data, a method using skid mark length to predict vehicle speed and position at brake application rather than skid onset was shown to improve estimates of initial vehicle speed by up to 10 km/h and estimates of vehicle position at brake application by up to 8 m compared to conventional methods that ignore the post-brake/pre-skid interval. PMID:15203360

Heinrichs, Bradley E; Allin, Boyd D; Bowler, James J; Siegmund, Gunter P

2004-09-01

475

Design Considerations and Experimental Verification of a Rail Brake Armature Based on Linear Induction Motor Technology  

NASA Astrophysics Data System (ADS)

This paper describes the design considerations and experimental verification of an LIM rail brake armature. In order to generate power and maximize the braking force density despite the limited area between the armature and the rail and the limited space available for installation, we studied a design method that is suitable for designing an LIM rail brake armature; we considered adoption of a ring winding structure. To examine the validity of the proposed design method, we developed a prototype ring winding armature for the rail brakes and examined its electromagnetic characteristics in a dynamic test system with roller rigs. By repeating various tests, we confirmed that unnecessary magnetic field components, which were expected to be present under high speed running condition or when a ring winding armature was used, were not present. Further, the necessary magnetic field component and braking force attained the desired values. These studies have helped us to develop a basic design method that is suitable for designing the LIM rail brake armatures.

Sakamoto, Yasuaki; Kashiwagi, Takayuki; Hasegawa, Hitoshi; Sasakawa, Takashi; Fujii, Nobuo

476

14 CFR 25.1435 - Hydraulic systems.  

Code of Federal Regulations, 2013 CFR

...designed to use any suitable hydraulic fluid specified by the...must be conducted on the hydraulic system(s...failure conditions, and to support or validate element design. (3) The complete hydraulic system(s)...

2013-01-01

477

14 CFR 25.1435 - Hydraulic systems.  

Code of Federal Regulations, 2010 CFR

...designed to use any suitable hydraulic fluid specified by the...must be conducted on the hydraulic system(s...failure conditions, and to support or validate element design. (3) The complete hydraulic system(s)...

2010-01-01

478

14 CFR 25.1435 - Hydraulic systems.  

Code of Federal Regulations, 2010 CFR

...designed to use any suitable hydraulic fluid specified by the...must be conducted on the hydraulic system(s...failure conditions, and to support or validate element design. (3) The complete hydraulic system(s)...

2009-01-01

479

14 CFR 29.1435 - Hydraulic systems.  

Code of Federal Regulations, 2010 CFR

...systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each element of the hydraulic system must be designed to withstand... (2) Each element of the hydraulic system must be designed to...

2010-01-01

480

HYDRAULIC CONTROL ROD DRIVE MECHANISM  

Microsoft Academic Search

The hydraulic control rod drive mechanism described is housed in a ; thimble attached to and extending outward from the reactor vessel. The drive ; mechanism uses reactor coolant medium as the hydraulic fluid. Within the housing ; there are two concentrically arranged hollow, cylindrically shaped members to one ; of which the piston is attached. One of the two

Kumpf

1963-01-01

481

POLYCRYSTALLINE DIAMOND COMPACT BIT HYDRAULICS  

Microsoft Academic Search

It is well understood and documented that bottomhole hydraulics plays an important role in conventional diamond bit performance. Recent industry experience has shown a similar importance with the new synthetic diamond compact bits. Certain types of polycrystalline diamond compact bits have cutters arranged in a reverse spiral mode. For optimum performance bit hydraulic design should be tailored to that reverse

R. H. Knowlton; Hsin Huang; B. Iversen

1982-01-01

482

Wind powered hydraulic heating system  

Microsoft Academic Search

A heating apparatus is described which includes a circulation system for hydraulic fluid, a pump for pumping the fluid, a windmill for driving the pump, an adjustable pressure responsive relief valve for restricting the flow of hydraulic fluid in the circulation system and establishing therein an adjustable fluid pressure reduction, a sensor responsive to the wind velocity encountered by the

1978-01-01

483

Hydraulics. FOS: Fundamentals of Service.  

ERIC Educational Resources Information Center

|This manual on hydraulics is one of a series of power mechanics texts and visual aids for training in the servicing of agricultural and industrial machinery. Focus is on oil hydraulics. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and laymen. The twelve chapters focus…

John Deere Co., Moline, IL.

484

Tractor Hydraulics. A Teaching Reference.  

ERIC Educational Resources Information Center

|The manual was developed to help provide a better understanding of how and why hydraulic principles serve the purposes of weight reduction, increase of physical effort, and more precise control to machines of all types. The four components that are necessary to have a workable hydraulic system--a reservoir, a pump, a valve, and a motor (cylinder)…

American Association for Vocational Instructional Materials, Athens, GA.

485

VORTICITY IN HYDRAULIC POWER EQUIPMENT  

Microsoft Academic Search

The paper presents a numerical simulation and analysis of the flow inside a hydraulic poppet valve and hydraulic control valve. This paper summarizes the successful application of Computational Fluid Dynamics (CFD) analysis to study the effect of spool slot configuration on spool and cavitation generation inside both the poppet valve and control valve. The hidrodynamic field inside in the valve

Romeo F. SUSAN-RESIGA

486

Superheater Hydraulic Model Test Plan.  

National Technical Information Service (NTIS)

The plan for conducting a hydraulic test on a full scale model of the AI Steam Generator Module design is presented. The model will incorporate all items necessary to simulate the hydraulic performance characteristics of the superheater but will utilize m...

M. Gabler R. M. Oliva

1973-01-01

487

Hydraulically actuated well shifting tool  

SciTech Connect

This patent describes a hydraulically actuated shifting tool for actuating a sliding member in a well tool. It comprises: a housing having a hydraulic fluid bore therein; shifting dog means positioned on the housing for movement away and toward the housing; locking dog means positioned on the housing for movement away and toward the body; shifting dog hydraulic actuating means in fluid communication with the bore for causing engagement of the shifting dogs with the sliding member; locking dog hydraulic actuating means in communication with the bore for causing engagement of the locking dogs with the locking means; and hydraulic shifting means in communication with the bore for causing relative movement between the shifting dog means and the locking dog means for shifting the sliding sleeve.

Roth, B.A.

1992-10-20

488

Hydraulic fracture analysis method  

SciTech Connect

A method of determining the orientation of a hydraulic fracture plane in the earth is described, consisting of: positioning an array of sensors for measuring seismic ground motion above a region which includes the fracture, providing a well bore having fluid therein communicating with the fracture to be defined, perturbing the fluid to cause transient pressure or flow oscillations in the fluid column in the well bore, measuring seismic ground motion induced by the transient pressure and flow oscillations in the fracture, calculating, using theory of wave propagation, the ground motion expected of fractures of different orientations, comparing the measured ground motion with the calculated ground motion patterns representing fractures of different orientations, selecting the fracture orientation that yields calculated seismic ground motions most closely resembling the measured seismic ground motions as the most probable fracture orientation, and calculating a probable fracture orientation based on the seismic motion of the ground.

Holzhausen, G.R.; St. Lawrence, W.

1989-01-31

489

High temperature hydraulic seals  

NASA Astrophysics Data System (ADS)

This program investigated and evaluated high temperature hydraulic sealing technology, including seals, fluids, and actuator materials. Test limits for fluid pressure and temperature were 8000 psi and 700 F respectively. The original plan to investigate CTFE fluid at 350 F as well as other fluids at higher temperatures was reduced in scope to include only the higher temperature investigation. Seals were obtained from 11 manufacturers. Design requirements including materials, dimensions, clearances, and tolerances were established and test modules were constructed from the detail designs which were produced. Nine piston seals and one rod seal were tested at temperatures ranging from -65 to +600 F and pressures to 6000 psi. Fluid performance under these conditions was evaluated. Details of this activity and results of the effort are summarized in this report.

Williams, K. R.

1993-05-01

490

Preliminary survey report: evaluation of brake-drum service controls at Louisville Gas and Electric Company, Louisville, Kentucky  

Microsoft Academic Search

A survey of technology for controlling exposure to asbestos during brake-drum service operators was conducted. The major component of the engineering-control system was a Nilfisk Asbestos\\/Clene system that removed asbestos fibers generated while servicing the brakes. Each system consisted of a filtered dust collector and a brake-encapsulation cylinder. The workers were encouraged to use good work practices, such as completely

Godbey

1985-01-01

491

Tribological Properties of Short Fiber C\\/SiC Brake Materials and 30CrSiMoVA Mate  

Microsoft Academic Search

In this study, the short fiber C\\/SiC brake materials were prepared by a combined process of the fibers dipped with resin,\\u000a chopping, warm pressing, pyrolyzing, and the liquid silicon infiltration process. The tribological properties of short fiber\\u000a C\\/SiC brake materials and 30CrSiMoVA mate were investigated. The results indicated that the average friction coefficient decreased\\u000a with the increase of braking speed

Shangwu Fan; Junzhan Zhang; Litong Zhang; Laifei Cheng; Guanglai Tian; Haiping Liu

492

Microstructure and frictional properties of 3D needled C\\/SiC brake materials modified with graphite  

Microsoft Academic Search

The 3D needled C\\/SiC brake materials modified with graphite were prepared by a combined process of the chemical vapor infiltration, slurry infiltration and liquid silicon infiltration process. The microstructure and frictional properties of the brake materials were investigated. The density and open porosity of the materials as-received were about (2.1±0.1) g\\/cm3 and (5±1)%, respectively. The brake materials were composed of

Jian-xin ZHANG; Shang-wu FAN; Li-tong ZHANG; Lai-fei CHENG; Shang-jie YANG; Guang-lai TIAN

2010-01-01

493

Macroautophagy can press a brake on presynaptic neurotransmission  

PubMed Central

The mechanistic target of rapamycin (MTOR) has been implicated in regulating synaptic plasticity and neurodegeneration, but MTOR’s role in modulating presynaptic function through autophagy is unexplored. We studied presynaptic function in ventral dopamine neurons, a system from which neurotransmitter release can be measured directly by cyclic voltammetry. We generated mutant mice that were specifically deficient for macroautophagy in dopaminergic neurons by deleting the Atg7 gene in cells that express the dopamine uptake transporter. Dopamine axonal profiles in the mutant dorsal striatum were ~one third larger in the mutant mice, released ~50% more stimulus-evoked dopamine release, and exhibited more rapid presynaptic recovery than controls. Rapamycin reduced dopamine neuron axon profile size by ~30% in control mice, but had no effect on macroautophagy deficient axons. Acute rapamycin decreased dopaminergic synaptic vesicle density by ~25% and inhibited evoked dopamine release by ~25% in control mice, but not in the Atg7 deficient mutants. Thus, both basal and induced macroautophagy can provide a brake on presynaptic activity in vivo, perhaps by regulating the turnover of synaptic vesicles, and further regulates terminal volume and the kinetics of transmitter release.

Torres, Ciara A.; Sulzer, David

2012-01-01

494

Hydraulic design of Three Gorges right bank powerhouse turbine for improvement of hydraulic stability  

NASA Astrophysics Data System (ADS)

This paper presents the hydraulic design of Three Gorges Right Bank Powerhouse turbine for improvement of hydraulic stability. The technical challenges faced in the hydraulic design of the turbine are given. The method of hydraulic design for improving the hydraulic stability and particularly for eliminating the upper part load pressure pulsations is clarified. The final hydraulic design results of Three Gorges Right Bank Powerhouse turbine based on modern hydraulic design techniques are presented.

Shi, Q.

2010-08-01

495

Toxic effects of brake wear particles on epithelial lung cells in vitro  

PubMed Central

Background Fine particulate matter originating from traffic correlates with increased morbidity and mortality. An important source of traffic particles is brake wear of cars which contributes up to 20% of the total traffic emissions. The aim of this study was to evaluate potential toxicological effects of human epithelial lung cells exposed to freshly generated brake wear particles. Results An exposure box was mounted around a car's braking system. Lung cells cultured at the air-liquid interface were then exposed to particles emitted from two typical braking behaviours („full stop“ and „normal deceleration“). The particle size distribution as well as the brake emission components like metals and carbons was measured on-line, and the particles deposited on grids for transmission electron microscopy were counted. The tight junction arrangement was observed by laser scanning microscopy. Cellular responses were assessed by measurement of lactate dehydrogenase (cytotoxicity), by investigating the production of reactive oxidative species and the release of the pro-inflammatory mediator interleukin-8. The tight junction protein occludin density decreased significantly (p < 0.05) with increasing concentrations of metals on the particles (iron, copper and manganese, which were all strongly correlated with each other). Occludin was also negatively correlated with the intensity of reactive oxidative species. The concentrations of interleukin-8 were significantly correlated with increasing organic carbon concentrations. No correlation was observed between occludin and interleukin-8, nor between reactive oxidative species and interleukin-8. Conclusion These findings suggest that the metals on brake wear particles damage tight junctions with a mechanism involving oxidative stress. Brake wear particles also increase pro-inflammatory responses. However, this might be due to another mechanism than via oxidative stress.

2009-01-01

496

Electrokinetic high pressure hydraulic system  

SciTech Connect

A compact high pressure hydraulic pump having no moving mechanical parts for converting electric potential to hydraulic force. The electrokinetic pump, which can generate hydraulic pressures greater than 2500 psi, can be employed to compress a fluid, either liquid or gas, and manipulate fluid flow. The pump is particularly useful for capillary-base systems. By combining the electrokinetic pump with a housing having chambers separated by a flexible member, fluid flow, including high pressure fluids, is controlled by the application of an electric potential, that can vary with time.

Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA)

2000-01-01

497

Design of hydraulic output Stirling engine  

Microsoft Academic Search

A hydraulic output system for the RE-1000 free piston stirling engine (FPSE) was designed. The hydraulic output system can be readily integrated with the existing hot section of RE-1000 FPSE. The system has two simply supported diaphragms which separate the engine gas from the hydraulic fluid, a dynamic balance mechanism, and a novel, null center band hydraulic pump. The diaphragms

W. M. Toscano; A. C. Harvey; K. Lee

1983-01-01

498

The Virtual Laboratory of Machine Tool Hydraulics  

NSDL National Science Digital Library

The Virtual Laboratory of Machine Tool Hydraulics is an interactive, web-based graphic animation of machine tool hydraulics. It includes fundamentals, troubleshooting, problem-solving, and interactive demonstrations of hydraulic circuits and components. This is a great interactive activity for those interested in learning the fundamental concepts of hydraulic systems.

Song, Xueshu

2009-10-29

499

Electroslag Welding on Hydraulic Machinery.  

National Technical Information Service (NTIS)

The use of consumable guide electroslag welding process with components for hydraulic machinery having curved and profiled seams is described. Tests were carried out to optimize the welding parameters and the mechanical properties of welding joints with c...

E. Schorer F. J. Edel A. Borontschuk

1983-01-01

500

Low energy consumption hydraulic techniques  

NASA Astrophysics Data System (ADS)

This report documents the efforts to develop and test low energy consumption hydraulic techniques. Included is a discussion of the efforts to select and analyze a baseline hydraulic system (Phase 1) and conduct trade studies on various candidate design approaches which could reduce weight and power consumption (Phase 2). In addition, the report discusses the development of a test plan (Phase 3) and the results of an endurance test (Phase 4). This program was directed at 8000 psi hydraulic system technology using a nonflammable hydraulic fluid chlorotrifluoroethylene (CTFE) although the concepts developed could be applied to any fluid at any system pressure. The concepts selected for test were variable system pressure, flow augmentation with load recovery valves and overlapped main valves.

Greene, J. B.; Jeffrey, J. R.; Lohe, S. N.; Pehowski, S. E.; Pierce, N. J.

1988-08-01