Sample records for hydraulic brakes

  1. Combined hydraulic and regenerative braking system

    DOEpatents

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

    1981-06-02

    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.

  2. Combined hydraulic and regenerative braking system

    SciTech Connect

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

    1981-06-02

    A combined hydraulic and regenerative braking system and method is disclosed for an electric vehicle. 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.

  3. 49 CFR 570.55 - Hydraulic brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 false Hydraulic brake system. 570.55 Section 570...000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles with hydraulic brake systems. (a) Brake system...

  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 570...000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles with hydraulic brake systems. (a) Brake system...

  5. 49 CFR 570.55 - Hydraulic brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 false Hydraulic brake system. 570.55 Section 570...000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles with hydraulic brake systems. (a) Brake system...

  6. 49 CFR 570.55 - Hydraulic brake system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 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...

  7. Disturbance Control of the Hydraulic Brake in a Wind Turbine

    E-print Network

    Yang, Zhenyu

    Disturbance Control of the Hydraulic Brake in a Wind Turbine Frank Jepsen, Anders Søborg brake in a wind turbine. Brake torque is determined by friction coefficient and clamp force; the latter brake is one1 of the two independent brake systems in a wind turbine. As a consequence of the gearing

  8. The study of the wheeled anti-lock hydraulic brake

    Microsoft Academic Search

    Junxia Li; Ziming Kou

    2010-01-01

    Adopting the mechanism of transient working system, the article studies the brake and steady installment of the mine belt conveyor - the wheeled anti-lock hydraulic brake. Using the PLC, software and switch sensor, the installment can make the loose brake process safe and controllable, the supervisory system consisted of the speed sensor and PLC can make the brake control the

  9. Modified hydraulic braking system limits angular deceleration to safe values

    NASA Technical Reports Server (NTRS)

    Briggs, R. S.; Council, M.; Green, P. M.

    1966-01-01

    Conventional spring actuated, hydraulically released, fail-safe disk braking system is modified to control the angular deceleration of a massive antenna. The hydraulic system provides an immediate preset pressure to the spring-loaded brake shoes and holds it at this value to decelerate the antenna at the desired rate.

  10. COUNTERWEIGHT, CONNECTED TO HYDRAULIC BRAKE SYSTEM, IN REAR OF VAULT ...

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

    COUNTERWEIGHT, CONNECTED TO HYDRAULIC BRAKE SYSTEM, IN REAR OF VAULT MOTOR ROOM, LOOKING SOUTHWEST. - Mad River Glen, Single Chair Ski Lift, 62 Mad River Glen Resort Road, Fayston, Washington County, VT

  11. 68 FR 62417 - Federal Motor Vehicle Safety Standards; Hydraulic and Electric Brake Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2003-11-04

    ...105, Hydraulic and electric brake systems, applies...Vehicles and Passenger Car Bodies, prescribes a...process of converting an image of text, such as a scanned...105; Hydraulic and electric braking systems...seat area in passenger cars, multipurpose...

  12. Research on new automobile power hydraulic braking system by vibratory energy

    Microsoft Academic Search

    Ding Zhi-hua; Lei Zheng-bao; Lei Mu-xi

    2011-01-01

    A new automobile power hydraulic braking system by vibratory energy is introduced which includes four vibration dampers, four energy accumulators, hydraulic booster, one storage tank, four wheel cylinders, four electromagnetic one-way valves, brake master cylinder, vacuum booster, brake pedal and loading sensing pressure proportioning valve(LSPV). Vibration damper is composed of nitrogen cavity, piston, piston rod, shell, rebound valve, compression valve,

  13. Hydraulic brake system modeling and control for active control of vehicle dynamics

    Microsoft Academic Search

    M. L. Kuang; M. Fodor; D. Hrovat; M. Tran

    1999-01-01

    Active control of vehicle dynamics has become one of the top competitive features in today's automobiles. Vehicle dynamic control systems include antilock brakes, traction control and yaw control. The realization of these systems relies on the control of hydraulic brakes as well as other vehicle systems. Modeling of the hydraulic brake system is essential to the design of vehicle dynamic

  14. Piezoelectric-hydraulic pump based band brake actuation system for automotive transmission control

    Microsoft Academic Search

    Gi-Woo Kim; K. W. Wang

    2007-01-01

    The actuation system of friction elements (such as band brakes) is essential for high quality operations in modern automotive automatic transmissions (in short, ATs). The current band brake actuation system consists of several hydraulic components, including the oil pump, the regulating valve and the control valves. In general, it has been recognized that the current AT band brake actuation system

  15. Design of a hydraulic anti-lock braking system (ABS) for a motorcycle

    Microsoft Academic Search

    Chun-Kuei Huang; Ming-Chang Shih

    2010-01-01

    This work presents a hydraulic anti-lock braking system (ABS) for a motorcycle. The ABS has a hydraulic modulator and an intelligent\\u000a controller. The hydraulic modulator is analyzed, and then equipped on a scooter for road tests. The intelligent controller\\u000a controls the hydraulic modulator by estimated vehicle velocity to calculate the slip ratio of the wheels in real time. The\\u000a performance

  16. Piezoelectric-hydraulic pump based band brake actuation system for automotive transmission control

    NASA Astrophysics Data System (ADS)

    Kim, Gi-Woo; Wang, K. W.

    2007-04-01

    The actuation system of friction elements (such as band brakes) is essential for high quality operations in modern automotive automatic transmissions (in short, ATs). The current band brake actuation system consists of several hydraulic components, including the oil pump, the regulating valve and the control valves. In general, it has been recognized that the current AT band brake actuation system has many limitations. For example, the oil pump and valve body are relatively heavy and complex. Also, the oil pumps induce inherently large drag torque, which affects fuel economy. This research is to overcome these problems of the current system by exploring the utilization of a hybrid type piezo-hydraulic pump device for AT band brake control. This new actuating system integrates a piezo-hydraulic pump to the input of the band brake. Compared with the current systems, this new actuator features much simpler structure, smaller size, and lower weight. This paper describes the development, design and fabrication of the new stand-alone prototype actuator for AT band brake control. An analytical model is developed and validated using experimental data. Performance tests on the hardware and system simulations utilizing the validated model are performed to characterize the new prototype actuator. It is predicted that with increasing of accumulator pressure and driving frequency, the proposed prototype actuating system will satisfy the band brake requirement for AT shift control.

  17. Model based fault detection of vehicle suspension and hydraulic brake systems

    Microsoft Academic Search

    Marcus Börner; Harald Straky; Thomas Weispfenning; Rolf Isermann

    2002-01-01

    In modern vehicles, mechatronic systems are increasingly used. To improve reliability, safety and economy, an early recognition of small or drifting faults is becoming increasingly important. After a short introduction to methods of model based fault detection and diagnosis, application examples for fault detection of automotive vehicle suspension and hydraulic brake systems are given.

  18. Fault diagnosis of automobile hydraulic brake system using statistical features and support vector machines

    NASA Astrophysics Data System (ADS)

    Jegadeeshwaran, R.; Sugumaran, V.

    2015-02-01

    Hydraulic brakes in automobiles are important components for the safety of passengers; therefore, the brakes are a good subject for condition monitoring. The condition of the brake components can be monitored by using the vibration characteristics. On-line condition monitoring by using machine learning approach is proposed in this paper as a possible solution to such problems. The vibration signals for both good as well as faulty conditions of brakes were acquired from a hydraulic brake test setup with the help of a piezoelectric transducer and a data acquisition system. Descriptive statistical features were extracted from the acquired vibration signals and the feature selection was carried out using the C4.5 decision tree algorithm. There is no specific method to find the right number of features required for classification for a given problem. Hence an extensive study is needed to find the optimum number of features. The effect of the number of features was also studied, by using the decision tree as well as Support Vector Machines (SVM). The selected features were classified using the C-SVM and Nu-SVM with different kernel functions. The results are discussed and the conclusion of the study is presented.

  19. 49 CFR 393.40 - Required brake systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (b) Service brakes —(1) Hydraulic brake systems. Motor vehicles equipped with hydraulic brake systems and manufactured on or after September...failure of service brakes —(1) Hydraulic brake systems. Motor vehicles...

  20. 49 CFR 393.40 - Required brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (b) Service brakes —(1) Hydraulic brake systems. Motor vehicles equipped with hydraulic brake systems and manufactured on or after September...failure of service brakes —(1) Hydraulic brake systems. Motor vehicles...

  1. 49 CFR 393.40 - Required brake systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (b) Service brakes —(1) Hydraulic brake systems. Motor vehicles equipped with hydraulic brake systems and manufactured on or after September...failure of service brakes —(1) Hydraulic brake systems. Motor vehicles...

  2. Automotive Brake Systems.

    ERIC Educational Resources Information Center

    Marine Corps Inst., Washington, DC.

    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…

  3. 49 CFR 393.53 - Automatic brake adjusters and brake adjustment indicators.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...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...

  4. Hydraulic Drivetrain and Regenerative Braking Team 13: Andrew Brown, Karan Desai, Andrew McGrath, Hurst Nuckols, Grant Wilson Adviser: Dr. Andrew Jackson

    E-print Network

    Carpick, Robert W.

    Hydraulic Drivetrain and Regenerative Braking Team 13: Andrew Brown, Karan Desai, Andrew Mc Pressure Reservior Filter Variable Vane Pump Motor/Pump Hydraulic Accumulators Solenoid Valve Relief Valve Suction Line Since their development in 2006, hydraulic drivetrain systems have gained considerable

  5. 49 CFR 393.55 - Antilock brake systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...OPERATION Brakes § 393.55 Antilock brake systems. (a) Hydraulic brake systems. Each truck and bus manufactured on...driveaway-towaway operations), and equipped with a hydraulic brake system, shall be equipped with an antilock...

  6. 49 CFR 393.55 - Antilock brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...OPERATION Brakes § 393.55 Antilock brake systems. (a) Hydraulic brake systems. Each truck and bus manufactured on...driveaway-towaway operations), and equipped with a hydraulic brake system, shall be equipped with an antilock...

  7. 49 CFR 393.55 - Antilock brake systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...OPERATION Brakes § 393.55 Antilock brake systems. (a) Hydraulic brake systems. Each truck and bus manufactured on...driveaway-towaway operations), and equipped with a hydraulic brake system, shall be equipped with an antilock...

  8. 76 FR 7623 - Parts and Accessories Necessary for Safe Operation; Brakes; Application for Exemption From...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-10

    ...self-contained, permanently closed hydraulic brake system'' [Emphasis added...FMCSRs to allow the use of automatic hydraulic inertia brake systems (surge brakes...self-contained, permanently closed hydraulic brake system for trailers that...

  9. Studies of regenerative braking in electric vehicle

    Microsoft Academic Search

    M. K. Yoong; Y. H. Gan; G. D. Gan; C. K. Leong; Z. Y. Phuan; B. K. Cheah; K. W. Chew

    2010-01-01

    Generally the braking system for a car is based on hydraulic braking technology. However, this traditional braking methodology causes a lot of energy wastage since it produces unwanted heat during braking. Thus, the invention of regenerative braking in electric car has overcome these disadvantages moreover it helps in save energy and provides higher efficiency for a car. In regenerative mode,

  10. Combined control of a regenerative braking and antilock braking system for hybrid electric vehicles

    Microsoft Academic Search

    D. Peng; Y. Zhang; C.-L. Yin; J.-W. Zhang

    2008-01-01

    Most parallel hybrid electric vehicles (HEV) employ both a hydraulic braking system and a regenerative braking system to provide\\u000a enhanced braking performance and energy regeneration. A new design of a combined braking control strategy (CBCS) is presented\\u000a in this paper. The design is based on a new method of HEV braking torque distribution that makes the hydraulic braking system\\u000a work

  11. Modeling and Simulation about an Electric Car's Regenerative Braking System

    Microsoft Academic Search

    Zuowu Ding; Dongbiao Zhao; Jianmin Zuo

    2007-01-01

    A kind of regenerative braking system of an electric car is studied in the paper. The car's speed, acceleration, the hydraulic accumulator's pressure and volume are simulated with Matlab while the electric car is braking or accelerating from stop. The hydraulic accumulator can absorb all of the braking energy when braking and the energy stored in the hydraulic accumulator can

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

    SciTech Connect

    VanSelous, J.S.; Abar, R.B.

    1989-07-04

    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 connected to the source of line pressure for producing second control pressure having a magnitude related to the magnitude of the first control pressure; an accumulator having a piston moveable within a cylinder, a first volume located at one side of the piston communicating with second control pressure, and a second volume located at the opposite side of the piston communicating with the line pressure source; accumulator control valve means supplied with fluid from the line pressure source for communicating the line pressure source to the friction element and the second volume; and rate means for controlling the flow rate of fluid from the accumulator control valve means to the second volume.

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

    ERIC Educational Resources Information Center

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

  14. Contactless magnetic brake for automotive applications 

    E-print Network

    Gay, Sebastien Emmanuel

    2009-05-15

    for road and rail vehicles, and carbon fiber for aircraft. The stator comprises shoes (drum brakes) or pads (disc brakes) made of a soft friction material and an actuator, generally a hydraulic piston. Although the principle is the same for drum... and disc brakes, the terminology used from there on refers to disc brakes. The contact between the soft material of the pads and the surface of the rotor is characterized by a high friction coefficient. When braking is commanded by the driver...

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

    ERIC Educational Resources Information Center

    Hilley, Robert; Scarberry, Terry; Kellum, Mary

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

  16. An Instructor's Guide for a Program in Brake Services.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

    The instructor's guide is designed to present an understanding of the automotive hydraulic brake system and to help individuals develop new skills for employment in this specialized field of automotive service. Applicable for secondary or adult education, this guide describes: the brake system, types of brakes, diagnosis and correction of brake

  17. Automobile Brake-by-Wire Control System Design and Analysis

    Microsoft Academic Search

    Weidong Xiang; Paul C. Richardson; Chenming Zhao; Syed Mohammad

    2008-01-01

    The automobile brake-by-wire (BBW) system, which is also called the electromechanical brake system, has become a promising vehicle braking control scheme that enables many new driver interfaces and enhanced performances without a mechanical or hydraulic backup. In this paper, we survey BBW control systems with focuses on fault tolerance design and vehicle braking control schemes. At first, the system architecture

  18. Hydraulics.

    ERIC Educational Resources Information Center

    Decker, Robert L.; Kirby, Klane

    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)…

  19. Comparison between software simulation and HIL simulation of antiskid brake system for aircrafts

    Microsoft Academic Search

    Ki-Chang Lee; Jeong-Woo Jeon; Don-Ha Hwang; Yong-Joo Kim

    2005-01-01

    Today, most fixed-wing aircrafts are equipped with an antiskid brake system (ABS). The ABS can modulate braking moments in the wheels optimally whenever an aircraft lands. So it can reduce landing distance and increase safeties. The ABS for an aircraft is mainly composed of braking moment modulators (hydraulic servo valves) and brake control unit in addition to the conventional hydraulic

  20. Design considerations for an automotive magnetorheological brake Kerem Karakoc, Edward J. Park *, Afzal Suleman

    E-print Network

    Park, Edward

    in automobiles. In other words, the traditional mechanical systems are being re- placed by improved advantages over conventional hydraulic brake (CHB) systems. A CHB system involves the brake pedal, hydraulic such as anti-lock braking system (ABS), vehicle stability control (VSC), electronic parking brake (EPB

  1. Hydraulics.

    ERIC Educational Resources Information Center

    Engelbrecht, Nancy; And Others

    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 identifies…

  2. 78 FR 21189 - Agency Requests for Approval of a New Information Collection: Motor Vehicle Brake Fluids

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-09

    ...brake fluids as well as packagers of hydraulic system mineral oils. The information...requirements for motor vehicle brake fluids and hydraulic system mineral oils. Section 5.2...brake fluids as well as packagers of hydraulic system mineral oils. The...

  3. Electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, S.R.

    1995-09-12

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.

  4. Gravity brake

    DOEpatents

    Lujan, Richard E. (Santa Fe, NM)

    2001-01-01

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

  5. Hydraulics.

    ERIC Educational Resources Information Center

    Decker, Robert L.

    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,…

  6. Better Brakes

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Through continuing studies on high-temperature space materials useful for better brake linings, Bendix Corporation worked with Ames Research Center to develop a novel composite. This team worked to fabricate several combinations of composite materials and evaluated results. The one selected increases wear rates and lowers costs. It exhibits constant coefficient of friction at temperatures as high as 650 degrees Fahrenheit, a region where conventional brake linings fade markedly. Other suitable markets include brakes for trucks and industrial equipment such as overhead cranes and hoists. Afterwards brake linings could find successful application in passenger cars.

  7. Braking system

    DOEpatents

    Norgren, D.U.

    1982-09-23

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

  8. Electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, Susan R. (Wixom, MI)

    1995-01-01

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.

  9. 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.

  10. Engine brake control in automatic transmission

    SciTech Connect

    Hayasaki, K.; Sugano, K.

    1988-09-13

    This patent describes an engine braking control for a transmission for an automotive vehicle having an engine, the transmission including an input member drivingly coupled to the engine and an output member subject to load from driving wheels of the automotive vehicle, the transmission also including a first rotary member, a second rotary member, a hydraulically operated clutch selectively establishing a drive connection between the first rotary member and the second rotary member, and a one-way clutch arranged in parallel to the hydraulically operated clutch such that when the hydraulically operated clutch is released, the one-way clutch transmits forward torque from the first rotary member to the second rotary member, but interrupts transmission of revers torque to the first rotary member from the second rotary member, the engine braking control comprising: means for providing an engine braking command fluid pressure signal when demanded by a vehicle operator; a valve means for normally discharging hydraulic fluid from the hydraulically operated clutch to deactivate the hydraulically operated clutch, the valve means being fluidly connected to the hydraulically operated clutch, the engine braking command fluid pressure signal providing means and a drain port. The valve means including a valve spool having a first position where the hydraulically operated clutch is allowed to communicate with the drain port to permit discharge of hydraulic fluid therefrom and thus the hydraulically operated clutch is caused to be deactivated and a second position where the hydraulically operated clutch is disconnected from the drain port and allowed to communicate with the engine braking command fluid pressure signal.

  11. Hydrobus, gyrobus use brake-generated energy

    SciTech Connect

    Scott, D.

    1980-04-01

    M.A.N. of Munich is developing a hydrobus concept, involving hydraulic pressure as the storage medium, and a gyrobus system with flywheel energy storage. Mercedes-Benz is also working on a gyrobus design. The hydraulic storage regenerative-braking design and the flywheel storage in the gyrobus are explained.

  12. 49 CFR 393.45 - Brake tubing and hoses; hose assemblies and end fittings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...contacting the vehicle's exhaust system or any other source of high temperatures...connections for air, vacuum, or hydraulic braking systems shall be installed so as to...affect the performance of the brake system. [70 FR 48050, Aug....

  13. Compression relief engine brake

    SciTech Connect

    Meneely, V.A.

    1987-10-06

    A compression relief brake is described for four cycle internal-combustion engines, comprising: a pressurized oil supply; means for selectively pressurizing a hydraulic circuit with oil from the oil supply; a master piston and cylinder communicating with a slave piston and cylinder via the hydraulic circuit; an engine exhaust valve mechanically coupled to the engine and timed to open during the exhaust cycle of the engine the exhaust valve coupled to the slave piston. The exhaust valve is spring-based in a closed state to contact a valve seat; a sleeve frictionally and slidably disposed within a cavity defined by the slave piston which cavity communicates with the hydraulic circuit. When the hydraulic circuit is selectively pressurized and the engine is operating the sleeve entraps an incompressible volume of oil within the cavity to generate a displacement of the slave piston within the slave cylinder, whereby a first gap is maintained between the exhaust valve and its associated seat; and means for reciprocally activating the master piston for increasing the pressure within the previously pressurized hydraulic circuit during at least a portion of the expansion cycle of the engine whereby a second gap is reciprocally maintained between the exhaust valve and its associated seat.

  14. Fuzzy logic electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, S.R.

    1994-10-25

    An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control. 123 figs.

  15. Fuzzy logic electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, Susan R. (Wixom, MI)

    1994-01-01

    An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control.

  16. Hydraulic drive system prevents backlash

    NASA Technical Reports Server (NTRS)

    Acord, J. D.

    1965-01-01

    Hydraulic drive system uses a second drive motor operating at reduced torque. This exerts a relative braking action which eliminates the normal gear train backlash that is intolerable when driving certain heavy loads.

  17. Research on brake disk modal characteristic of disk brake

    Microsoft Academic Search

    Liya Yao

    2011-01-01

    The brake disk modal characteristic of disk brake is an important factor for braking stability of the whole system. In order to reduce the judder and noise in braking process, the ANSYS software was applied to conduct the modal simulation analysis of brake disk, and a multi-purpose experimental bench was built for modal test of brake disk. The results including

  18. TGV disc brake squeal

    NASA Astrophysics Data System (ADS)

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

    2006-06-01

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

  19. TGV disc brake squeal

    Microsoft Academic Search

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

    2006-01-01

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

  20. Automotive disc brake squeal

    Microsoft Academic Search

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

    2003-01-01

    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

  1. Commercial Motor Vehicle Brake Assessment Tools

    E-print Network

    ability #12;Performance-Based Brake Tester · Assessment of brake efficiency ­ BE = ­ Equivalent performance Total Braking Force Total Vehicle Weight Total Braking Force Total Vehicle Weight #12;Related

  2. Brake Fundamentals. Automotive Articulation Project.

    ERIC Educational Resources Information Center

    Cunningham, Larry; And Others

    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…

  3. Intelligent control for brake systems

    Microsoft Academic Search

    William K. Lennon; Kevin M. Passino

    1999-01-01

    There exist several problems in the control of brake systems including the development of control logic for antilock braking systems (ABS) and “base-braking.” Here, we study the base-braking control problem where we seek to develop a controller that can ensure that the braking torque commanded by the driver will be achieved. In particular, we develop a fuzzy model reference learning

  4. An antilock molecular braking system.

    PubMed

    Sun, Wei-Ting; Huang, Shou-Ling; Yao, Hsuan-Hsiao; Chen, I-Chia; Lin, Ying-Chih; Yang, Jye-Shane

    2012-08-17

    A light-driven molecular brake displaying an antilock function is constructed by introducing a nonradiative photoinduced electron transfer (PET) decay channel to compete with the trans (brake-off) ? cis (brake-on) photoisomerization. A fast release of the brake can be achieved by deactivating the PET process through addition of protons. The cycle of irradiation-protonation-irradiation-deprotonation conducts the brake function and mimics the antilock braking system (ABS) of vehicles. PMID:22853709

  5. Power assisted hydraulic control

    SciTech Connect

    Dauvergne, J.L.R.

    1984-05-22

    The invention provides a power assisted hydraulic control system suitable for actuating clutches and brakes. The system incorporates a master cylinder having a master piston therein defining a control chamber, a hydraulic power assistance unit, and a distributor adapted to connect, by means of a slide valve, the power assistance unit with the hydraulic receiver controlling the brake or clutch unit. The distributor comprises a slide-valve having a plunger one end of which is subjected to the pressure in the control chamber and the other end of which is subjected to the pressure in the receiver. A bypass channel links the control chamber of the master cylinder to the pipeline connecting the operating port of the distributor to the receiver. The bypass channel has a bypass valve controlled by a spring which opens in the event of failure of the power assistance to permit manual operation by the master piston.

  6. A Robust Force Controller for an SRM Based Electromechanical Brake System

    Microsoft Academic Search

    P. Krishnamurthy; W. Lu; F. Khorrami; A. Keyhani

    2005-01-01

    In this paper, we propose a robust nonlinear force controller for a switched reluctance motor (SRM) electromechanical brake system which is a promising replacement for hydraulic brakes in the automotive industry. A detailed model of the motor including current dependent inductance coefficients is used. The load exerted on the motor by the caliper may be modeled as a spring; however,

  7. Brake for rollable platform

    NASA Technical Reports Server (NTRS)

    Morris, A. L.

    1974-01-01

    Frame-mounted brake is independent of wheels and consists of simple lever-actuated foot. Brake makes good contact with surface even though foot pad is at higher or lower level than wheels, this is particularly important when a rollable platform is used on irregular surface.

  8. 29 CFR 1919.22 - Requirements governing braking devices and power sources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...and the efficiency of such means shall be demonstrated. Electric winches, electrohydraulic winches fitted with electromagnetic or hydraulic brakes at the winch, or electric cranes shall be equipped so that a failure of the electric power...

  9. 29 CFR 1919.22 - Requirements governing braking devices and power sources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...and the efficiency of such means shall be demonstrated. Electric winches, electrohydraulic winches fitted with electromagnetic or hydraulic brakes at the winch, or electric cranes shall be equipped so that a failure of the electric power...

  10. Improved Electromagnetic Brake

    NASA Technical Reports Server (NTRS)

    Martin, Toby B.

    2004-01-01

    A proposed design for an electromagnetic brake would increase the reliability while reducing the number of parts and the weight, relative to a prior commercially available electromagnetic brake. The reductions of weight and the number of parts could also lead to a reduction of cost. A description of the commercial brake is prerequisite to a description of the proposed electromagnetic brake. The commercial brake (see upper part of figure) includes (1) a permanent magnet and an electromagnet coil on a stator and (2) a rotor that includes a steel contact plate mounted, with tension spring loading, on an aluminum hub. The stator is mounted securely on a stationary object, which would ordinarily be the housing of a gear drive or a motor. The rotor is mounted on the shaft of the gear drive or motor. The commercial brake nominally operates in a fail-safe (in the sense of normally braking) mode: In the absence of current in the electromagnet coil, the permanent magnet pulls the contact plate, against the spring tension, into contact with the stator. To release the brake, one excites the electromagnet with a current of the magnitude and polarity chosen to cancel the magnetic flux of the permanent magnet, thereby enabling the spring tension to pull the contact plate out of contact with the stator. The fail-safe operation of the commercial brake depends on careful mounting of the rotor in relation to the stator. The rotor/stator gap must be set with a tolerance between 10 and 15 mils (between about 0.25 and about 0.38 mm). If the gap or the contact pad is thicker than the maximum allowable value, then the permanent magnetic field will not be strong enough to pull the steel plate across the gap. (For this reason, any contact pad between the contact plate and the stator must also be correspondingly thin.) If the gap exceeds the maximum allowable value because of shaft end play, it becomes impossible to set the brake by turning off the electromagnet current. Although it may still be possible to set the brake by applying an electromagnet current to aid the permanent magnetic field instead of canceling it, this action can mask an out-of-tolerance condition in the brake and it does not restore the fail-safe function of setting the brake when current is lost.

  11. Braking System for Wind Turbines

    NASA Technical Reports Server (NTRS)

    Krysiak, J. E.; Webb, F. E.

    1987-01-01

    Operating turbine stopped smoothly by fail-safe mechanism. Windturbine braking systems improved by system consisting of two large steel-alloy disks mounted on high-speed shaft of gear box, and brakepad assembly mounted on bracket fastened to top of gear box. Lever arms (with brake pads) actuated by spring-powered, pneumatic cylinders connected to these arms. Springs give specific spring-loading constant and exert predetermined load onto brake pads through lever arms. Pneumatic cylinders actuated positively to compress springs and disengage brake pads from disks. During power failure, brakes automatically lock onto disks, producing highly reliable, fail-safe stops. System doubles as stopping brake and "parking" brake.

  12. Vehicle brake testing system

    DOEpatents

    Stevens, Samuel S. (Harriman, TN); Hodgson, Jeffrey W. (Lenoir City, TN)

    2002-11-19

    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.

  13. From Brake to Syzygy

    E-print Network

    Moeckel, Richard; Venturelli, Andrea

    2011-01-01

    In the planar three-body problem, we study solutions with zero initial velocity (brake orbits). Following such a solution until the three masses become collinear (syzygy), we obtain a continuous, flow-induced Poincar\\'e map. We study the image of the map in the set of collinear configurations and define a continuous extension to the Lagrange triple collision orbit. In addition we provide a variational characterization of some of the resulting brake-to-syzygy orbits and find simple examples of periodic brake orbits.

  14. Control performance of an electrorheological valve based vehicle anti-lock brake system, considering the braking force distribution

    NASA Astrophysics Data System (ADS)

    Choi, S. B.; Lee, T. H.; Lee, Y. S.; Han, M. S.

    2005-12-01

    This paper presents the braking control performance of a vehicle anti-lock brake system featuring an electrorheological (ER) fluid. As a first step, a cylindrical type of ER valve is devised and its pressure controllability is experimentally confirmed. Then, a hydraulic booster for amplifying the field-dependent pressure drop obtained from the ER valve is constructed and its pressure amplification is demonstrated by presenting the pressure tracking control performance. Subsequently, the governing equation of the rear wheel model is derived by considering the braking force distribution, and a sliding mode controller for achieving the desired slip rate is designed. The controller is then realized through the hardware-in-the-loop simulation method and controlled responses are presented in the time domain. In addition, computer animations for the braking performance under unladen and laden conditions are presented, and a comparison of the proportioning valve and the proposed ER valve pressure modulator is made.

  15. Apply the Brakes

    NSDL National Science Digital Library

    The representation depicts a dot moving across the screen together with two graphs of the dot's motion. An arrow shows the dot's velocity and marks appear at regular time intervals show the dot's position at different clock readings. The dot moves at a constant velocity until the user presses a button marked "Brake," at which point the dot slows to a stop. Sliders allow the user to change the dot's initial velocity and the braking acceleration.

  16. Unidirectional high gain brake stop

    NASA Technical Reports Server (NTRS)

    Lang, David J. (Inventor)

    1987-01-01

    This invention relates to a unidirectional high gain brake arrangement that includes in combination a shaft mounted for rotation within a housing. The shaft is rotatable in either direction. A brake is selectively releasably coupled to the housing and to the shaft. The brake has a first member. An intermittent motion device is respectively coupled through the first member to the housing and through a one-way clutch to the shaft. The brake also has a second member that is mechanically coupled to the first brake member and to the housing. The intermittent motion device causes the brake to be activated by movement imparted to the first brake member after a preset number of revolutions of the shaft in one direction. The brake is released by rotation of the shaft in an opposite direction whereby torque transmitted through the one-way clutch to the first brake member is removed.

  17. Pneumatic train brake simulation method

    Microsoft Academic Search

    Tadeusz Piechowiak

    2009-01-01

    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

  18. Chaos in brake squeal noise

    Microsoft Academic Search

    S. Oberst; J. C. S. Lai

    2011-01-01

    Brake squeal has become an increasing concern to the automotive industry because of warranty costs and the requirement for continued interior vehicle noise reduction. Most research has been directed to either analytical and experimental studies of brake squeal mechanisms or the prediction of brake squeal propensity using finite element methods. By comparison, there is a lack of systematic analysis of

  19. Simulation Of Antilock Braking System

    Microsoft Academic Search

    Imdad A. Rizvi; Dinesh Chawde

    This paper develops the anti-lock braking control system integrated with active suspensions applied to a two wheeler. In emergency, although the braking distance can be reduced by the control torque, the braking time and distance can be further improved if the normal force generated from active suspension systems is considered simultaneously. Finally the future developments on the ABS are dwelt

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

    NASA Astrophysics Data System (ADS)

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

    2007-08-01

    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 of chemically treated starch particles and silicone oil is used. An electrically controllable pressure modulator is then constructed and its pressure controllability is empirically evaluated. Subsequently, a quarter-car wheel slip model is established and integrated with the governing equation of the pressure modulator. A sliding mode controller for slip rate control is designed and implemented via the hardware-in-the-loop simulation (HILS). In order to demonstrate the superior braking performance of the proposed ABS, a full car model is derived and a sliding mode controller is formulated to achieve the desired yaw rate. The braking performances in terms of braking distance and step input steering are evaluated and presented in time domain through full car simulations.

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

    NASA Astrophysics Data System (ADS)

    Sarkar, C.; Hirani, H.

    2013-02-01

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

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

    NASA Astrophysics Data System (ADS)

    Nastasoiu, Mircea; Ispas, Nicolae

    2014-06-01

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

  3. 49 CFR 236.508 - Interference with application of brakes by means of brake valve.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Transportation 4 2012-10-01 2012-10-01 false Interference with application of brakes by means of brake valve. 236...Control and Cab Signal Systems Standards § 236.508 Interference with application of brakes by means of brake...

  4. 49 CFR 236.508 - Interference with application of brakes by means of brake valve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Transportation 4 2010-10-01 2010-10-01 false Interference with application of brakes by means of brake valve. 236...Control and Cab Signal Systems Standards § 236.508 Interference with application of brakes by means of brake...

  5. Robust Force Control of an SRM-Based Electromechanical Brake and Experimental Results

    Microsoft Academic Search

    Prashanth Krishnamurthy; Wenzhe Lu; Farshad Khorrami; Ali Keyhani

    2009-01-01

    In this paper, we propose robust nonlinear force controllers for a switched-reluctance-motor (SRM) electromechanical brake system which is a promising replacement for hydraulic brakes in the automotive industry. A torque-level control law is first designed using robust backstepping. The backstepping proceeds via the force and the velocity states. The voltage-level control laws are obtained from the virtual control law for

  6. Optimization of parallel regenerative braking control strategy

    Microsoft Academic Search

    Zhang Jingming; Song Baoyu; Niu Xiaojing

    2008-01-01

    Regenerative braking system is the own system of electric and hybrid electric vehicle. The system can restore the kinetic energy and potential energy, used during start and accelerating, into battery through electrical machine. The total brake force is composed of friction brake force on front axel, friction brake force on rear axel and regenerative brake force when a vehicle equipped

  7. Experiments with airplane brakes

    NASA Technical Reports Server (NTRS)

    Michael, Franz

    1931-01-01

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

  8. Brake assembly including torque monitor

    SciTech Connect

    Dillmann, C.W.

    1992-07-21

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

  9. Brake Initiation and Braking Dynamics: A HumanCentered Study of Desired ACC Characteristics

    E-print Network

    Goodrich, Michael A.

    Brake Initiation and Braking Dynamics: A Human­Centered Study of Desired ACC Characteristics into conditions which generate active braking and conditions which permit nominal behavior. In words, these set to brake, braking dynamics are characterized by smooth trajectories in perceptual space terminating

  10. Brake Initiation and Braking Dynamics: A Human-Centered Study of Desired ACC Characteristics

    E-print Network

    Goodrich, Michael A.

    Brake Initiation and Braking Dynamics: A Human-Centered Study of Desired ACC Characteristics into conditions which generate active braking and conditions which permit nominal behavior. In words, these set to brake, braking dynamics are characterized by smooth trajectories in perceptual space terminating

  11. Hydraulic control system for automatic transmission

    SciTech Connect

    Sakaguchi, Y

    1989-05-16

    A hydraulic control system is described for an automatic transmission including hydraulic servos for clutches and brakes to engage and disengage components in the transmission gear mechanism and having a forward clutch hydraulic servo and a brake hydraulic servo, and a manual valve, comprising:a modulator valve for adjusting line pressure to a predetermined modulator pressure; a control valve adapted to be shifted in response to signals based on positions of the manual valve and the vehicle running condition; a first oil path connected between the control valve and the manual valve as a line pressure oil path; the control valve including a first port connecting to the forward clutch hydraulic servo; a second oil path connected between the control valve and the brake hydraulic servo; and a shift valve situated in the second oil path, the shift valve not operating during a low speed vehicle condition, the shift valve being adapted to connect the second oil path when the shift valve shifts to a low speed position and to disconnect the oil path when the shift valve shifts to a high speed position.

  12. EXPERIMENTAL MODAL ANALYSIS OF BRAKE SQUEAL NOISE

    Microsoft Academic Search

    MUHAMMAD ZAHIR HASSAN

    Disc brake squeal noise continues to be the major problem concern for the automotive industry. In this paper, the brake squeal phenomenon of brake rotor disc had been investigated using experimental modal analysis (EMA). The modal analysis excitation technique known as impact hammer test has been carried out to obtain modal parameter of brake disc structure namely the natural frequencies

  13. Regenerative braking strategy for electric vehicles

    Microsoft Academic Search

    Jingang Guo; Junping Wang; Binggang Cao

    2009-01-01

    Regenerative braking is an effective approach for electric vehicles to extend their driving range. The control strategy of regenerative braking plays an important role in maintaining the vehicle's stability and recovering energy. In this paper, the main properties that have influence on brake energy regeneration are analyzed. Mathematical model of brake energy regenerating electric vehicles is established. By analyzing the

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

    ERIC Educational Resources Information Center

    Human Engineering Inst., Cleveland, OH.

    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…

  15. Hydraulic system design for full hybrid transmission

    Microsoft Academic Search

    Han Bing; Cai Yixi; Zhang Tong

    2011-01-01

    The design method of hydraulic system of power split full hybrid transmission is studied. Oil volume flow and pressure requirement is confirmed according to the vehicle control strategy. Mechanical gear pump and electric pump are used to supply oil flow for all driving modes. Self-adapted pressure regulation circuit is designed to supply high pressure oil for brake engagement. Dynamic model

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

    ERIC Educational Resources Information Center

    Schramm, C.; Osland, Walt

    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)…

  17. Wheel brakes and their application to aircraft

    NASA Technical Reports Server (NTRS)

    Dowty, G H

    1928-01-01

    The advantages to be gained from braking have not been ignored, and in the search for a suitable method many schemes have been suggested and tried. Some of the methods discussed in this paper include: 1) increasing the height of the landing gear; 2) air brakes of various forms; 3) sprags on tail skid and axle; and 4) wheel brakes. This report focuses on the design of wheel brakes and wheel brake controls.

  18. Single acting translational/rotational brake

    NASA Technical Reports Server (NTRS)

    Allred, Johnny W. (Inventor); Fleck, Jr., Vincent J. (Inventor)

    1996-01-01

    A brake system is provided that applies braking forces on surfaces in both the translational and rotational directions using a single acting self-contained actuator that travels with the translational mechanism. The brake engages a mechanical lock and creates a frictional force on the translational structure preventing translation while simultaneously creating a frictional torque that prevents rotation of the vertical support. The system may include serrations on the braking surfaces to provide increased braking forces.

  19. Brake Stops Both Rotation And Translation

    NASA Technical Reports Server (NTRS)

    Allred, Johnny W.; Fleck, Vincent J., Jr.

    1995-01-01

    Combination of braking and positioning mechanisms allows both rotation and translation before brake engaged. Designed for use in positioning model airplane in wind tunnel. Modified version used to position camera on tripod. Brake fast and convenient to use; contains single actuator energizing braking actions against both rotation and translation. Braking actuator electric, but pneumatic actuator could be used instead. Compact and lightweight, applies locking forces close to load, and presents minimal cross section to airflow.

  20. Regenerative braking device

    DOEpatents

    Hoppie, Lyle O. (Birmingham, MI)

    1982-01-12

    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.

  1. Variable ratio regenerative braking device

    DOEpatents

    Hoppie, Lyle O. (Birmingham, MI)

    1981-12-15

    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.

  2. Experimental Research on Brake Squeal

    NASA Astrophysics Data System (ADS)

    Wallner, Daniel; Bernsteiner, Stefan

    Since many years experimental researches have been performed in order to get an insight into the issue of brake squeal. This work presents an innovative test setup for analyzing friction-excited vibrations and squeal triggering mechanisms. The investigated brake system showed brake squeal issues at certain operating points. The purpose was to analyse the brake system in detail on a test rig. Because the well-known methods of investigation such as laser vibrometer were not possible, the aim was to develop and generate new measuring points, which are close to the contact area of disc and pad. Therefore the brake calliper has been modified; hence the guide are replaced by modified ones. At these pins the friction force can be measured. Because of an optimized shape it is possible to measure the vibration of the friction force. The measured signal correlates with a parallel measured microphone signal. Next the brake disc will be assembled with triaxial accelerometers. Thus it is possible to determine the operating deflection shape of the disc. With the results of this work a new contact algorithm should be developed which can be used e.g. in Finite Element calculations.

  3. Anti-skid brake control system for automotive vehicle with feature of assuring prevention of wheel-locking at any driving condition

    SciTech Connect

    Matsuda, T.

    1989-02-14

    An anti-skid brake control system is described for an automotive vehicle, comprising: a hydraulic brake circuit including wheel cylinders for establishing braking pressure for decelerating vehicular wheels; first and second anti-skid brake control valves, each associated at least one of first and second wheel cylinders which are associated with first and second wheels for adjusting braking pressure therein, each of the anti-skid brake control valves being operable to increase braking pressure in the associated wheel cylinder in a first mode position, and to decrease the braking pressure in the associated wheel cylinder in a second mode position; first sensor for monitoring rotation speed of the first wheel for producing a first wheel speed indicative signal; second sensor for monitoring rotation speed of the second wheel for producing a second wheel speed indicative signal; first means for monitoring wheel slippage at the first and second wheels based on the first and second wheel speed indicative signals and detecting a wheel slippage at one of the first and second wheels when the wheel slippage increases across a given slippage threshold for operating the first and second anti-skid brake control valves in the second mode position; and second means for detecting the first and second wheel speed indicative signals for operating the first and second anti-skid brake control valves in the first mode position when a predetermined brake condition is satisfied while the first and second anti-skid brake control valves are in the second mode position, the second means increasing a rate of braking pressure in the first and second wheel cylinders in response to the detection so that the braking pressure in a third wheel cylinder is increased at a greater increasing rate than that in a fourth wheel cylinder.

  4. Hydraulic control device for automatic transmissions

    SciTech Connect

    Sakaguchi, Y.; Taga, Y.; Kashihara, Y.

    1989-06-20

    This patent describes a hydraulic control device for an automatic transmission including a control unit, a shift gear mechanism, clutches and brakes for controlling the shift gear mechanism, hydraulic servos for actuating the clutches and brakes to control the shift gear mechanism and having hydraulic servo for a forward clutch, and an electronically operated regulating value for regulating pressure according to signals from the control unit. The control device consists of: a selecting value switched by signals indicating stopping and running condition of a vehicle, the selecting valve being connected to the hydraulic servo for the forward clutch for engaging and transmitting torque during the forward running conditon, the selecting valve selectively receiving a line pressure and a control pressure from the regulating valve so that hydraulic pressure just below engaging pressure regulated by the regulating valve is applied to the hydraulic servo for the forward clutch during stopping, and a line pressure is applied to the hydraulic servo for the forward clutch during running.

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

    E-print Network

    Paris-Sud XI, Université de

    are also inferred from these calculations. Keywords: brake squeal noise, stochastic, friction, eigenvalue problem 1. Introduction Brake squeal noise is a real problem for the automotive [1, 2] and railway [3Piecewise polynomial chaos expansion with an application to brake squeal of a linear brake system E

  6. Measuring Braking Indices for Young, Energetic Pulsars

    Microsoft Academic Search

    M. A. Livingstone; V. M. Kaspi; F. P. Gavriil; R. N. Manchester

    2004-01-01

    Pulsar braking indices are only measurable for the very youngest of objects. In all cases, values less than 3 (for magnetic dipole radiation) have been reported. Due in large part to contamination from timing noise, values of the braking index or the second braking index for several of these objects have been called into question. We present an updated timing

  7. Statistical analysis of brake squeal noise

    Microsoft Academic Search

    S. Oberst; J. C. S. Lai

    2011-01-01

    Despite substantial research efforts applied to the prediction of brake squeal noise since the early 20th century, the mechanisms behind its generation are still not fully understood. Squealing brakes are of significant concern to the automobile industry, mainly because of the costs associated with warranty claims. In order to remedy the problems inherent in designing quieter brakes and, therefore, to

  8. Compact, Lightweight Servo-Controllable Brakes

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

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

  9. The dynamics of antilock brake systems

    NASA Astrophysics Data System (ADS)

    Denny, Mark

    2005-11-01

    The nonlinear dynamics of automobile braking are investigated. Nonlinearity arises because of the manner in which the friction coefficient between vehicle tyres and road surface depends upon vehicle speed and wheel angular speed. We show how antilock brake systems approach optimum braking performance.

  10. The dynamics of antilock brake systems

    Microsoft Academic Search

    Mark Denny

    2005-01-01

    The nonlinear dynamics of automobile braking are investigated. Nonlinearity arises because of the manner in which the friction coefficient between vehicle tyres and road surface depends upon vehicle speed and wheel angular speed. We show how antilock brake systems approach optimum braking performance.

  11. An Antilock-Braking Algorithm for an Eddy-Current-Based Brake-By-Wire System

    Microsoft Academic Search

    Sohel Anwar; Bing Zheng

    2007-01-01

    This paper presents a nonlinear sliding-mode-type controller for slip regulation in a braking event for an electromagnetic brake-by-wire (BBW)-system-equipped automobile. The electromagnetic BBW system under consideration consists of a set of eddy current brakes (ECBs) attached to the automobile wheels. The antilock-braking controller modifies the brake torque command generated by a supervisory controller which, in turn, is based on the

  12. ENVIRONMENTAL HYDRAULICS

    EPA Science Inventory

    The thermal, chemical, and biological quality of water in rivers, lakes, reservoirs, and near coastal areas is inseparable from a consideration of hydraulic engineering principles: therefore, the term environmental hydraulics. In this chapter we discuss the basic principles of w...

  13. Bidirectional drive and brake mechanism

    NASA Technical Reports Server (NTRS)

    Swan, Scott A. (inventor)

    1991-01-01

    A space transport vehicle is disclosed as including a body which is arranged to be movably mounted on an elongated guide member disposed in outer space and driven therealong. A drive wheel is mounted on a drive shaft and arranged to be positioned in rolling engagement with the elongated guide carrying the vehicle. A brake member is arranged on the drive shaft for movement into and out of engagement with an adjacent surface of the drive wheel. An actuator is mounted on the body to be manually moved back and forth between spaced positions in an arc of movement. A ratchet-and-pawl mechanism is arranged to operate upon movements of the actuator in one direction between first and second positions for coupling the actuator to the drive wheel to incrementally rotate the wheel in one rotational direction and to operate upon movements of the actuator in the opposite direction for uncoupling the actuator from the wheel. The brake member is threadedly coupled to the drive shaft in order that the brake member will be operated only when the actuator is moved on beyond its first and second positions for shifting the brake member along the drive shaft and into frictional engagement with the adjacent surface on the drive wheel.

  14. Minimal models for squealing of railway block brakes

    Microsoft Academic Search

    Utz von Wagner; Gottfried Spelsberg-Korspeter

    2011-01-01

    Block brakes have been used to brake railway vehicles for approximately 200 years. During the last 40 years, disk brakes have\\u000a replaced the block brakes at passenger cars but block brakes are still used for all freight wagons. One problem of block brakes\\u000a is that they show an enormous tendency to squeal. Although the block brake is a very common and old

  15. Hydraulics Lectures

    NSDL National Science Digital Library

    Pytel, Jim

    This page from the WindTech TV project provides a link to lectures created by Jim Pytel for his hydraulics course at Columbia Gorge Community College. The lectures consist of live videos and screen capture style presentations and may be viewed free of charge. Clicking on the video link in the center of the page will lead users to a YouTube page with 31 lectures. Topics include hydraulics math, hydraulic safety, basic hydraulic schematics, viscosity, piston pumps, actuators, troubleshooting and more. These lectures would be extremely useful for technical and community college students taking a fundamental hydraulics course. Flash is required to view the videos.

  16. Electromagnetic braking for Mars spacecraft

    SciTech Connect

    Holt, A.C.

    1986-01-01

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

  17. Basics of Automotive Vehicle Braking

    Microsoft Academic Search

    B. T. Fijalkowski

    \\u000a It is necessary to have knowledge of the technology correlated with contemporary auto-motive vehicles’ BBW AWB dispulsion\\u000a to understand the wheel-tyre to on\\/off-road interface, vehicle dynamics during braking, and the components of a BBW AWB dispulsion\\u000a mechatronic control system. This section examines these issues to enhance the level of that knowledge.

  18. Braking performance of heavy U. S. vehicles

    SciTech Connect

    Radlinski, R.W.

    1987-01-01

    This paper provides a synthesis of the information available describing the braking performance of heavy (on-highway) vehicles in the U.S. and contrasts the braking performance of heavy vehicles with that of passenger cars. It discusses the unique demands that are placed on heavy vehicle brake systems and shows that it is difficult to optimize braking performance for all operating conditions without adding complexity to the system. As designed, U.S. heavy vehicles do not perform as well as cars. In addition, heavy vehicle brake performance can degrade significantly from the design-intent level if proper maintenance is not performed. The brake maintenance situation in the U.S. leaves something to be desired.

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

    Microsoft Academic Search

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

    2009-01-01

    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

  20. Engine brake control apparatus and method

    SciTech Connect

    Stepper, M.R.; White, G.R.; Seger, J.P.; Van Klompenburg, D.; Green, J.H.; Ling, R.

    1992-06-16

    This patent describes a compression brake controller for use with a vehicle having an engine, a clutch, a transmission, a compression brake apparatus having a brake input and activated in response to signals supplied to the brake input, and a throttle control device. It comprises fuel metering means for controlling fuel delivery to the engine; throttle position sensor means for sensing the position of the throttle control device; pressure sensor means in fluid communication with the intake manifold of the engine; control circuit means for supplying a fueling signal to the fuel signal input in accordance with the throttle signal; RPM sensor means for producing an RPM signal corresponding to engine RPM; and brake circuit means for supplying a braking signal to the brake input of the compression brake apparatus in accordance with concurrence of the following conditions. This patent also describes a method for activating and deactivating a compression brake in an internal combustion having a throttle control. It comprises detecting a throttle control position below a predetermined throttle limit; detecting an intake manifold pressure below a predetermined pressure limit; detecting an engine speed above a predetermined RPM limit; detecting a fuel metering signal corresponding to a fueling rate below a predetermined fueling limit.

  1. Clutches and brakes: Design and selection

    SciTech Connect

    Orthwein, W.C.

    1986-01-01

    Clutches and Brakes brings together formulas for the design and selection of a variety of brakes and clutches. Formulas for the torque that may be expected from each of the brake or clutch configurations and the force, pressure, or current required to obtain this torque are derived and their application demonstrated by example. Derivations are included to show explicitly the assumptions made and to delineate the role of each parameter in these governing relations so that the designer can more skillfully select parameters to meet the demands of the problem at hand. Clutches and Brakes also gives attention to the calculation of acceleration, temperature, and heat dissipation.

  2. 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...

  3. Performance of a disc brake friction material

    Microsoft Academic Search

    Pradnya Kosbe; Chittaranjan More

    2010-01-01

    The friction materials used in brakes are required to provide a stable coefficient of friction and a lower wear rate at various operating speeds, pressures, temperatures and environmental conditions. These friction materials must also be compatible with the rotor material in order to reduce its extensive wear, vibration and noise during braking. All of these requirements need to be achieved

  4. BRAKE SQUEAL NOISE: FINITE ELEMENT ANALYSIS

    Microsoft Academic Search

    MUHAMMAD ZAHIR HASSAN

    This paper investigated the brake disc squeal phenomenon using finite element analysis (FEA). The modal analysis has been used in this work to determine the natural frequency and mode shape pattern. The study on four different types of material properties is carried out to shows the effect of vibration mode and natural frequency as the source of brake squeal contribution.

  5. TMV Technology Capabilities Brake Stroke Monitor

    E-print Network

    TMV Technology Capabilities Brake Stroke Monitor Brake monitoring systems are proactive maintenance This technology allows for CMV operators to have knowledge of their steer, drive, and tandem axle group weights setup is required. Current Safety/Enforcement Technologies EOBR (electronic on-board recorder) On

  6. Study on regenerative braking of electric vehicle

    Microsoft Academic Search

    Zhang Chuanwei; Bai Zhifeng; Cao Binggang; Li Jingcheng

    2004-01-01

    This paper discusses the regenerative braking system for electric vehicle (EV) that performs regenerative energy recovery based on analytical deduction of several regenerative braking systems with the microscopic view of pulse width modulation (PWM) driving, a constant regenerative current control scheme is proposed, thereby providing improved performance and the energy recovery efficiency at minimum cost. Experimental results of EV show

  7. Method and apparatus for electromagnetically braking a motor

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  8. Some wear studies on aircraft brake systems

    NASA Technical Reports Server (NTRS)

    Ho, T. L.

    1975-01-01

    An initial investigation of worn surfaces in friction pads and steel rotors used in current aircraft brakes was carried out using electron microprobe and X-ray diffraction analysis. It consists of the topographical study and the analysis of chemical element distribution. Based upon this initial examination, two approaches, microscopic and macroscopic have been conducted to interpret and formulate the wear mechanism of the aircraft brake materials. Microscopically, the wear particles were examined. The initiation and growth of surface cracks and the oxidation were emphasized in this investigation. Macroscopically, it has been found that, for the current copper based brake material sliding against 17-22 AS steel in a caliper brake, the surface temperature raised due to frictional heat is nonlinearly proportional to the load applied and slide time with speed at 1750 rpm. The wear of brake materials is then proportional to this temperature and is also a function of the melting temperature for copper.

  9. 49 CFR 229.57 - Foundation brake gear.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Transportation 4 2010-10-01 2010-10-01 false Foundation brake gear. 229.57 Section 229.57 Transportation...STANDARDS Safety Requirements Brake System § 229.57 Foundation brake gear. A lever, rod, brake beam, hanger, or...

  10. Why Brake-By-Wire (BBW) ? Advantages of BBW

    E-print Network

    Yao, Bin

    at wheel] #12;Sectional Drawing of the Electromechanically Actuated Disk Brake From ITT Brake Pads Caliper Brake Disk Rim Contour 0.032[m] Pad Support [Sectional Drawing of the Continental Teves (formerly ITTWhy Brake-By-Wire (BBW) ? Advantages of BBW Shorter Stopping Distances & Optimized Stability

  11. Fleet Study Evaluation of an Advance Brake Warning System

    Microsoft Academic Search

    David Shinar

    2000-01-01

    The advance brake warning system (ABWS) is a mechanism that activates the brake lights in response to a rapid disengagement of the gas pedal, before the driver's foot reaches the brake pedal. Two previous studies showed that (a) such rapid releases of the gas pedal are typically followed by brake activation, and (b) the ABWS can prevent a high percentage

  12. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Front brake lines, protection. 393.44 ...Brakes § 393.44 Front brake lines, protection. On every...that in the event any brake line to any of the front wheels...restrained by any seat belt assembly provided for use. Every...

  13. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Front brake lines, protection. 393.44 ...Brakes § 393.44 Front brake lines, protection. On every...that in the event any brake line to any of the front wheels...restrained by any seat belt assembly provided for use. Every...

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

    ERIC Educational Resources Information Center

    Allain, Robert

    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…

  15. 49 CFR 229.47 - Emergency brake valve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Emergency brake valve. 229.47 Section 229.47 Transportation...Brake System § 229.47 Emergency brake valve. (a) Except for locomotives with...locomotive shall be equipped with a brake pipe valve that is accessible to a member of...

  16. 49 CFR 229.47 - Emergency brake valve.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Emergency brake valve. 229.47 Section 229.47 Transportation...Brake System § 229.47 Emergency brake valve. (a) Except for locomotives with...locomotive shall be equipped with a brake pipe valve that is accessible to a member of...

  17. 49 CFR 229.47 - Emergency brake valve.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Emergency brake valve. 229.47 Section 229.47 Transportation...Brake System § 229.47 Emergency brake valve. (a) Except for locomotives with...locomotive shall be equipped with a brake pipe valve that is accessible to a member of...

  18. 49 CFR 229.47 - Emergency brake valve.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Emergency brake valve. 229.47 Section 229.47 Transportation...Brake System § 229.47 Emergency brake valve. (a) Except for locomotives with...locomotive shall be equipped with a brake pipe valve that is accessible to a member of...

  19. 49 CFR 229.47 - Emergency brake valve.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Emergency brake valve. 229.47 Section 229.47 Transportation...Brake System § 229.47 Emergency brake valve. (a) Except for locomotives with...locomotive shall be equipped with a brake pipe valve that is accessible to a member of...

  20. 49 CFR 229.57 - Foundation brake gear.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Transportation 4 2014-10-01 2014-10-01 false Foundation brake gear. 229.57 Section 229.57 Transportation...STANDARDS Safety Requirements Brake System § 229.57 Foundation brake gear. A lever, rod, brake beam, hanger, or...

  1. 49 CFR 229.57 - Foundation brake gear.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Transportation 4 2012-10-01 2012-10-01 false Foundation brake gear. 229.57 Section 229.57 Transportation...STANDARDS Safety Requirements Brake System § 229.57 Foundation brake gear. A lever, rod, brake beam, hanger, or...

  2. 49 CFR 229.57 - Foundation brake gear.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Transportation 4 2013-10-01 2013-10-01 false Foundation brake gear. 229.57 Section 229.57 Transportation...STANDARDS Safety Requirements Brake System § 229.57 Foundation brake gear. A lever, rod, brake beam, hanger, or...

  3. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Front brake lines, protection. 393.44 ...Brakes § 393.44 Front brake lines, protection. On every...that in the event any brake line to any of the front wheels...restrained by any seat belt assembly provided for use. Every...

  4. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Front brake lines, protection. 393.44 ...Brakes § 393.44 Front brake lines, protection. On every...that in the event any brake line to any of the front wheels...restrained by any seat belt assembly provided for use. Every...

  5. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Front brake lines, protection. 393.44 ...Brakes § 393.44 Front brake lines, protection. On every...that in the event any brake line to any of the front wheels...restrained by any seat belt assembly provided for use. Every...

  6. Energy Management for Regenerative Brakes on a DC Feeding System

    Microsoft Academic Search

    Yuruki Okada; Takafumi Koseki; Satoru Sone

    Recently, regenerative brakes are implemented in trains at DC fed electric railways in Japan. Regenerative braking system converts kinetic energy to electrical energy. And other powering trains at the identical feeding circuit must consume the electrical energy. Therefore, when the electrical loads are not sufficient at feeding circuit, braking trains must squeeze regenerative power. The problem is that such braking

  7. Brake wear particle emissions: a review.

    PubMed

    Grigoratos, Theodoros; Martini, Giorgio

    2015-02-01

    Traffic-related sources have been recognized as a significant contributor of particulate matter particularly within major cities. Exhaust and non-exhaust traffic-related sources are estimated to contribute almost equally to traffic-related PM10 emissions. Non-exhaust particles can be generated either from non-exhaust sources such as brake, tyre, clutch and road surface wear or already exist in the form of deposited material at the roadside and become resuspended due to traffic-induced turbulence. Among non-exhaust sources, brake wear can be a significant particulate matter (PM) contributor, particularly within areas with high traffic density and braking frequency. Studies mention that in urban environments, brake wear can contribute up to 55 % by mass to total non-exhaust traffic-related PM10 emissions and up to 21 % by mass to total traffic-related PM10 emissions, while in freeways, this contribution is lower due to lower braking frequency. As exhaust emissions control become stricter, relative contributions of non-exhaust sources-and therefore brake wear-to traffic-related emissions will become more significant and will raise discussions on possible regulatory needs. The aim of the present literature review study is to present the state-of-the-art of the different aspects regarding PM resulting from brake wear and provide all the necessary information in terms of importance, physicochemical characteristics, emission factors and possible health effects. PMID:25318420

  8. Modeling regenerative braking and storage for vehicles

    SciTech Connect

    Wicks, F.; Donnelly, K. [Union Coll., Schenectady, NY (United States)

    1997-12-31

    The fuel savings benefits of regenerative braking and storage for vehicles are often described but not quantified. For example, the federal government and automobile manufacturers are sponsoring a Program for a New Generation of Vehicles (PGNV) with a goal of obtaining a performance of 80 mpg in a family size car. It is typically suggested that such a vehicle will be a hybrid engine and electric drive with regenerative braking. The authors note that while regenerative braking has the potential of saving fuel, it may also do more harm than good as a result of additional weight, less than ideal charge/discharge efficiency on the batteries or storage flywheels and the limited portion of the entire driving cycle when regenerative braking can be utilized. The authors also noted that if regenerative braking can have a net benefit, it would be on a heavy vehicle such as a municipal bus because of the frequent stop and go requirements for both traffic light and passengers. Thus the authors initiated a study of regenerative braking on such a vehicle. The resulting analysis presented in this paper includes data following municipal buses to define the driving cycle, modeling the bus power requirements from weight, aerodynamics and rolling resistance, and then calculating the fuel saving that could result from an ideal regenerative braking system.

  9. Asbestos dust exposure during brake repair

    SciTech Connect

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

    1986-01-01

    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.

  10. Statistical analysis of brake squeal noise

    NASA Astrophysics Data System (ADS)

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

    2011-06-01

    Despite substantial research efforts applied to the prediction of brake squeal noise since the early 20th century, the mechanisms behind its generation are still not fully understood. Squealing brakes are of significant concern to the automobile industry, mainly because of the costs associated with warranty claims. In order to remedy the problems inherent in designing quieter brakes and, therefore, to understand the mechanisms, a design of experiments study, using a noise dynamometer, was performed by a brake system manufacturer to determine the influence of geometrical parameters (namely, the number and location of slots) of brake pads on brake squeal noise. The experimental results were evaluated with a noise index and ranked for warm and cold brake stops. These data are analysed here using statistical descriptors based on population distributions, and a correlation analysis, to gain greater insight into the functional dependency between the time-averaged friction coefficient as the input and the peak sound pressure level data as the output quantity. The correlation analysis between the time-averaged friction coefficient and peak sound pressure data is performed by applying a semblance analysis and a joint recurrence quantification analysis. Linear measures are compared with complexity measures (nonlinear) based on statistics from the underlying joint recurrence plots. Results show that linear measures cannot be used to rank the noise performance of the four test pad configurations. On the other hand, the ranking of the noise performance of the test pad configurations based on the noise index agrees with that based on nonlinear measures: the higher the nonlinearity between the time-averaged friction coefficient and peak sound pressure, the worse the squeal. These results highlight the nonlinear character of brake squeal and indicate the potential of using nonlinear statistical analysis tools to analyse disc brake squeal.

  11. Performance of an aircraft tire under cyclic braking and of a currently operational antiskid braking system

    NASA Technical Reports Server (NTRS)

    Tanner, J. A.

    1972-01-01

    An experimental investigation was conducted to study the performance of an aircraft tire under cyclic braking conditions and to study the performance of a currently operational aircraft antiskid braking system. Dry, damp, and flooded runway surface conditions were used in the investigation. The results indicated that under cyclic braking conditions the braking and cornering-force friction coefficients may be influenced by fluctuations in the vertical load, flexibility in the wheel support, and the spring coupling between the wheel and the tire-pavement interface. The cornering capability was shown to be negligible at wheel slip ratios well below a locked-wheel skid under all test surface conditions. The maximum available brake-force friction coefficient was shown to be dependent upon the runway surface condition, upon velocity, and, for wet runways, upon tire differences. Moderate reductions in vertical load and brake system pressure did not significantly affect the overall wet-runway performance of the tire.

  12. Wear studies on aircraft brake materials

    NASA Technical Reports Server (NTRS)

    Ho, T. L.

    1977-01-01

    An investigation of both worn surfaces of friction pads and steel rotors which are being applied in current aircraft brakes has been carried out by employing an X-ray diffraction technique. It consists of the analysis of chemical element distribution in the surface layers. The wear particles were also examined by using the scanning electron microscope. The initiation and growth of surface cracks and the oxidation were emphasized in this investigation. A wear model was proposed for the current aircraft brake materials. Essentially this model proposed that cracks are formed in the surface layer of the brake material due to the normal and frictional stresses. It is primarily surface temperature dependent.

  13. Optimal design and selection of magneto-rheological brake types based on braking torque and mass

    NASA Astrophysics Data System (ADS)

    Nguyen, Q. H.; Lang, V. T.; Choi, S. B.

    2015-06-01

    In developing magnetorheological brakes (MRBs), it is well known that the braking torque and the mass of the MRBs are important factors that should be considered in the product’s design. This research focuses on the optimal design of different types of MRBs, from which we identify an optimal selection of MRB types, considering braking torque and mass. In the optimization, common types of MRBs such as disc-type, drum-type, hybrid-type, and T-shape types are considered. The optimization problem is to find an optimal MRB structure that can produce the required braking torque while minimizing its mass. After a brief description of the configuration of the MRBs, the MRBs’ braking torque is derived based on the Herschel-Bulkley rheological model of the magnetorheological fluid. Then, the optimal designs of the MRBs are analyzed. The optimization objective is to minimize the mass of the brake while the braking torque is constrained to be greater than a required value. In addition, the power consumption of the MRBs is also considered as a reference parameter in the optimization. A finite element analysis integrated with an optimization tool is used to obtain optimal solutions for the MRBs. Optimal solutions of MRBs with different required braking torque values are obtained based on the proposed optimization procedure. From the results, we discuss the optimal selection of MRB types, considering braking torque and mass.

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

    NASA Astrophysics Data System (ADS)

    Tavares, J. M.

    2009-07-01

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

  15. 30 CFR 36.29 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...OF MINING PRODUCTS APPROVAL REQUIREMENTS FOR PERMISSIBLE MOBILE DIESEL-POWERED TRANSPORTATION EQUIPMENT Construction and Design Requirements § 36.29 Brakes. All mobile diesel-powered transportation equipment shall be equipped...

  16. 30 CFR 36.29 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...OF MINING PRODUCTS APPROVAL REQUIREMENTS FOR PERMISSIBLE MOBILE DIESEL-POWERED TRANSPORTATION EQUIPMENT Construction and Design Requirements § 36.29 Brakes. All mobile diesel-powered transportation equipment shall be equipped...

  17. An engine air-brake integration study

    E-print Network

    Mulchandani, Hiten

    2011-01-01

    The feasibility of operating an engine air-brake (EAB) integrated with a pylon duct bifurcation in a realistic aircraft engine environment has been analyzed. The EAB uses variable exit guide vanes downstream of a high ...

  18. Effect of frictional heating on brake materials

    NASA Technical Reports Server (NTRS)

    Ho, T.-L.; Peterson, M. B.; Ling, F. F.

    1974-01-01

    An exploratory study of the properties of aircraft brake materials was made to determine ways of improving friction and wear behavior while minimizing surface temperatures. It is found that frictional variation at high temperature involves material softening and metal transfer, formation of oxides, and surface melting. The choice of proper materials to combat these effects is discussed. Minimum surface temperatures are found to result from use of materials with large density-specific heat and density-specific heat-conductivity factors, use of a higher load-lower friction system, and maximization of the contact area. Some useful trade-off criteria for the size of brake disks against weight considerations are suggested. Additional information on material behavior and peak braking temperatures was gathered from an inspection of used brake pads and rotor disks.

  19. Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions

    Microsoft Academic Search

    Gi-Woo Kim; K. W. Wang

    2009-01-01

    In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in

  20. Hydraulic system for a ratio change transmission

    DOEpatents

    Kalns, Ilmars (Northville, MI)

    1981-01-01

    Disclosed is a drive assembly (10) for an electrically powered vehicle (12). The assembly includes a transaxle (16) having a two-speed transmission (40) and a drive axle differential (46) disposed in a unitary housing assembly (38), an oil-cooled prime mover or electric motor (14) for driving the transmission input shaft (42), an adapter assembly (24) for supporting the prime mover on the transaxle housing assembly, and a hydraulic system (172) providing pressurized oil flow for cooling and lubricating the electric motor and transaxle and for operating a clutch (84) and a brake (86) in the transmission to shift between the two-speed ratios of the transmission. The adapter assembly allows the prime mover to be supported in several positions on the transaxle housing. The brake is spring-applied and locks the transmission in its low-speed ratio should the hydraulic system fail. The hydraulic system pump is driven by an electric motor (212) independent of the prime mover and transaxle.

  1. Rotary Speed Sensor for Antilocking Brakes

    NASA Technical Reports Server (NTRS)

    Berdahl, C. M.

    1986-01-01

    Sensor based on fluidic principles produces negative pressure approximately proportional to rotational speed. Sensor developed as part of antilocking brake system for motorcycles. Uses inlet pressure rather than outlet pressure as braking-control signal, eliminating pressure pulsations caused by pump vanes and ensuring low-noise signal. Sensor is centrifugal air pump turned by one of motorcycle wheels. Air enters pump through orifice plates, and suction taken off through port in pump inlet plenum.

  2. An experimental study of perforated muzzle brakes

    NASA Astrophysics Data System (ADS)

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

    1984-06-01

    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.

  3. Method and apparatus for wind turbine braking

    DOEpatents

    Barbu, Corneliu (Laguna Hills, CA); Teichmann, Ralph (Nishkayuna, NY); Avagliano, Aaron (Houston, TX); Kammer, Leonardo Cesar (Niskayuna, NY); Pierce, Kirk Gee (Simpsonville, SC); Pesetsky, David Samuel (Greenville, SC); Gauchel, Peter (Muenster, DE)

    2009-02-10

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

  4. Power-Factor Controller With Regenerative Braking

    NASA Technical Reports Server (NTRS)

    Nola, F. J.

    1982-01-01

    Modified power-factor motor-control circuit operates motor as a phase-controlled generator when load attempts to turn at higher than synchronous speed. An induction motor is required to act at times as a brake. Circuit modification allows power-factor controller to save energy in motoring mode and convert automatically to an induction-generator controller in generating, or braking, mode.

  5. Parker Hybrid Hydraulic Drivetrain Demonstration

    SciTech Connect

    Collett, Raymond; Howland, James; Venkiteswaran, Prasad

    2014-03-31

    This report examines the benefits of Parker Hannifin hydraulic hybrid brake energy recovery systems used in commercial applications for vocational purposes. A detailed background on the problem statement being addressed as well as the solution set specific for parcel delivery will be provided. Objectives of the demonstration performed in high start & stop applications included opportunities in fuel usage reduction, emissions reduction, vehicle productivity, and vehicle maintenance. Completed findings during the demonstration period and parallel investigations with NREL, CALSTART, along with a literature review will be provided herein on this research area. Lastly, results identified in the study by third parties validated the savings potential in fuel reduction of on average of 19% to 52% over the baseline in terms of mpg (Lammert, 2014, p11), Parker data for parcel delivery vehicles in the field parallels this at a range of 35% - 50%, emissions reduction of 17.4% lower CO2 per mile and 30.4% lower NOx per mile (Gallo, 2014, p15), with maintenance improvement in the areas of brake and starter replacement, while leaving room for further study in the area of productivity in terms of specific metrics that can be applied and studied.

  6. Constraining the Braking Indices of Magnetars

    E-print Network

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

    2015-01-01

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

  7. Consideration of Materials for Aircraft Brakes

    NASA Technical Reports Server (NTRS)

    Peterson, M. B.; Ho, T.

    1972-01-01

    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 part of the investigation. A simple analysis was conducted in order to determine the most significant factors which affect surface temperatures. It was found that where size and weight restrictions are necessary, the specific heat of the material, and maintaining uniform contact area are the most important factors. A criterion was suggested for optimum sizing of the brake disks. Bench friction tests were run with brake materials. It was found that there is considerable friction variation due to the formation and removal of surface oxide films. Other causes of friction variations are surface softening and melting. The friction behavior at high temperature was found to be more characteristic of the steel surface rather than the copper brake material. It is concluded that improved brake materials are feasible.

  8. Characterisation of Semi-Metallic Brake Pads using Brake Dynamometer

    NASA Astrophysics Data System (ADS)

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

    2010-03-01

    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.

  9. Modeling hydraulic regenerative hybrid vehicles using AMESim and Matlab/Simulink

    NASA Astrophysics Data System (ADS)

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

    2005-05-01

    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 component hardware and was interlinked with a Matlab/Simulink model of the vehicle, engine and the control strategy required to operate the vehicle and the hydraulic hybrid system through various North American and European drive cycles.

  10. Hydraulic flywheel

    SciTech Connect

    Maxwell, T.J.

    1982-06-22

    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.

  11. Hydraulic plant

    Microsoft Academic Search

    1983-01-01

    The plant described resolves the problem of recovering the energy generated by heat engines under test, acceptance trials or experimental tests by the generation of alternating electrical current for which the alternator is always connected to the supply network even in the absence of mechanical energy produced by said engines under test, there being provided hydraulic pumping dynamometric units which

  12. Experimental analysis of brake squeal noise on a laboratory brake setup

    Microsoft Academic Search

    Oliviero Giannini; Adnan Akay; Francesco Massi

    2006-01-01

    The present paper is the first of two papers dealing with brake squeal instability. An experimental setup is specifically designed for this purpose and is characterized by a simple design to aid measurements and modeling. This first paper describes the experimental setup called “laboratory brake” and presents the measurements performed on it to characterize its dynamical behavior and its squeal

  13. Brake squeal reduction of vehicle disc brake system with interval parameters by uncertain optimization

    NASA Astrophysics Data System (ADS)

    Lü, Hui; Yu, Dejie

    2014-12-01

    An uncertain optimization method for brake squeal reduction of vehicle disc brake system with interval parameters is presented in this paper. In the proposed method, the parameters of frictional coefficient, material properties and the thicknesses of wearing components are treated as uncertain parameters, which are described as interval variables. Attention is focused on the stability analysis of a brake system in squeal, and the stability of brake system is investigated via the complex eigenvalue analysis (CEA) method. The dominant unstable mode is extracted by performing CEA based on a linear finite element (FE) model, and the negative damping ratio corresponding to the dominant unstable mode is selected as the indicator of instability. The response surface method (RSM) is applied to approximate the implicit relationship between the unstable mode and the system parameters. A reliability-based optimization model for improving the stability of the vehicle disc brake system with interval parameters is constructed based on RSM, interval analysis and reliability analysis. The Genetic Algorithm is used to get the optimal values of design parameters from the optimization model. The stability analysis and optimization of a disc brake system are carried out, and the results show that brake squeal propensity can be reduced by using stiffer back plates. The proposed approach can be used to improve the stability of the vehicle disc brake system with uncertain parameters effectively.

  14. Active Regenerative Braking: Braking of Induction Machine Traction Drive with Maximum Torque in High Speeds

    Microsoft Academic Search

    Zdenek Peroutka; Karel Zeman; Jiri Flajtingr

    2006-01-01

    This paper deals with the problem of the transmission of the energy to the dc trolley wire during the regenerative braking of the tram drive in case of the braking with increased dc-link voltage. The contribution presents new strategy called \\

  15. Simultaneous hydraulic fracturing

    Microsoft Academic Search

    Uhri

    1989-01-01

    A process is described for simultaneous hydraulic fracturing of a hydrocarbonaceous fluid-bearing formation comprising: (a) determining a hydraulic pressure necessary to fracture the formation from at least two wells which penetrate the formation; (b) injecting a hydraulic fracturing fluid into both wells under the determined hydraulic pressure; and (c) applying simultaneously the determined hydraulic pressure to the hydraulic fluid contained

  16. Electromagnetic brake/clutch device

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (inventor)

    1994-01-01

    An electromagnetic brake/clutch device includes a drive shaft supported by at least one bearing for transmitting torque, a housing, affixed to prevent its rotation, surrounding the drive shaft, and an electromagnetically activated device within the housing to selectively prevent and allow rotation of the drive shaft. The electromagnetically activated device includes a plurality of cammed rollers to prevent counter-clockwise rotation of the drive shaft. The drive shaft includes a circumferential disk and the housing includes a reaction ring for engagement with the plurality of cammed rollers. The plurality of cammed rollers are released from engagement with the circumferential disk and the reaction ring by a plurality of tripping mechanisms within the housing. The tripping action uses the locking force to act as a release force merely by changing the boundary conditions of the roller interface angles. The tripping mechanisms include trippers for disengaging the plurality of cammed rollers and an anvil shaped portion for providing lateral movement of the trippers. The plurality of cammed rollers is preloaded to engagement with the circumferential disk and reaction ring by a spring, and is located with respect to an adjacent tripping mechanism with another spring.

  17. Airborne wear particles railway research group FEM Simulation of train disc brake behavior

    E-print Network

    Haviland, David

    a modern train disc brake with brake caliper and high speed pads. During braking, a considerable amount of heat is generated in the contact patch and transfer into both of the brake disc and brake pad. Figure1 Airborne wear particles railway research group FEM Simulation of train disc brake behavior

  18. Regenerative Braking Algorithm for a HEV with CVT Ratio Control During Deceleration

    Microsoft Academic Search

    Hoon Yeo; Donghyun Kim; Sungho Hwang; Hyunsoo Kim

    A regenerative braking algorithm is proposed to make maximum use of regenerative brake for improvement of fuel consumption. In the regenerative braking algorithm, the regenerative torque is determined by considering the motor capacity, battery SOC and vehicle velocity. The regenerative braking force is calculated from the brake control unit by comparing the demanded brake force(torque) and the motor torque available.

  19. Motion capture of a pad measured with accelerometers during squeal noise in a real brake system

    NASA Astrophysics Data System (ADS)

    Renaud, Franck; Chevallier, Gaël; Dion, Jean-Luc; Taudière, Guillaume

    2012-11-01

    The operating deflection shape of a pad during squeal noise is measured on a real brake system with three-axis accelerometers. A time-frequency analysis is performed that highlights the dependency of squeal on the hydraulic pressure of the system and shows that squeal occurs simultaneously with harmonic components. The operating deflection shape of this pad before and during squeal is then visualized using interpolation, showing the predominance of bending motion. Finally, the pad motions observed are compared to the real modal basis of a detailed Finite Element model.

  20. Hydropneumatic energy reservoir for accumulating the braking energy recovered on a vehicle

    SciTech Connect

    Michel, R.

    1985-06-04

    Hydropneumatic energy reservoir for accumulating the braking energy recovered on a vehicle by means of a hydrostatic energy recovery-restoration device, combined or not with the vehicle transmission and working between a high-pressure accumulator and a low-pressure accumulator, characterized in that it comprises several oblong cylindrical hydropneumatic accumulators connected hydraulically in parallel and placed side by side inside a single casing of small height, the space included between the said casing and the said accumulators forming the low-pressure accumulator.

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

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

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

  2. 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

  3. Vehicle transfer gear and drive line brake mechanism

    SciTech Connect

    Richards, D.L.; Windish, W.E.

    1986-03-25

    This patent describes a vehicle transfer gear and drive line brake mechanism including a depending gear transfer train and a drive line brake assembly for respectively propelling and stopping movement of a vehicle. The gear transfer train has an output gear connected to an output shaft disposed on a lower axis and the drive line brake assembly is connected to the output shaft and disposed on the lower axis. The improvement described here consists of: housing means for defining an enclosed compartment containing the gear transfer train and the drive line brake assembly in juxtaposed relation and a common lubrication fluid. The housing means includes a main case defining an opening on the lower axis. The drive line brake assembly includes a brake body releasably secured to the case in closing relationship to the opening and annular plates and discs, the drive line brake assembly being modularized and being removable with the brake body from the output shaft independent of the output gear.

  4. 14 CFR 23.493 - Braked roll conditions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...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...

  5. 14 CFR 29.493 - Braked roll conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

  6. 14 CFR 27.493 - Braked roll conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  7. 14 CFR 23.493 - Braked roll conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...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...

  8. 14 CFR 23.493 - Braked roll conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...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...

  9. 14 CFR 27.493 - Braked roll conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

  10. 14 CFR 29.493 - Braked roll conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

  11. 14 CFR 29.493 - Braked roll conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  12. 14 CFR 27.493 - Braked roll conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

  13. Development of Diagnostic Algorithms for Air Brakes in Trucks

    E-print Network

    Dhar, Sandeep

    2011-10-21

    (T ) = 0:051 mm) for \\type 20" brake cham- ber estimated using the scheme : : : : : : : : : : : : : : : : : : : : : 76 41 Pushrod stroke (z1 bc(T ) = 0:061 mm) for \\type 30" brake cham- ber estimated using the scheme...

  14. 30 CFR 77.1401 - Automatic controls and brakes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Personnel Hoisting § 77.1401 Automatic controls and brakes. Hoists and elevators shall be equipped with overspeed, overwind, and automatic stop controls and with brakes capable of stopping the elevator when fully...

  15. 30 CFR 77.1401 - Automatic controls and brakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Personnel Hoisting § 77.1401 Automatic controls and brakes. Hoists and elevators shall be equipped with overspeed, overwind, and automatic stop controls and with brakes capable of stopping the elevator when fully...

  16. 30 CFR 77.1401 - Automatic controls and brakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Personnel Hoisting § 77.1401 Automatic controls and brakes. Hoists and elevators shall be equipped with overspeed, overwind, and automatic stop controls and with brakes capable of stopping the elevator when fully...

  17. 30 CFR 77.1401 - Automatic controls and brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Personnel Hoisting § 77.1401 Automatic controls and brakes. Hoists and elevators shall be equipped with overspeed, overwind, and automatic stop controls and with brakes capable of stopping the elevator when fully...

  18. 30 CFR 77.1401 - Automatic controls and brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Personnel Hoisting § 77.1401 Automatic controls and brakes. Hoists and elevators shall be equipped with overspeed, overwind, and automatic stop controls and with brakes capable of stopping the elevator when fully...

  19. 49 CFR 396.25 - Qualifications of brake inspectors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... INSPECTION, REPAIR, AND MAINTENANCE § 396.25 Qualifications of brake inspectors...maintenance, repairs or service to...brake inspector qualifications of paragraph...maintenance, service or repairs of any...

  20. Nonlinear stability analysis of a disk brake model

    Microsoft Academic Search

    Daniel Hochlenert

    2009-01-01

    It has become commonly accepted by scientists and engineers that brake squeal is generated by friction-induced self-excited\\u000a vibrations of the brake system. The noise-free configuration of the brake system loses stability through a flutter-type instability\\u000a and the system starts oscillating in a limit cycle. Usually, the stability analysis of disk brake models, both analytical\\u000a as well as finite element based,

  1. Improvements in the inspection procedure of brake disc warping

    Microsoft Academic Search

    D. García-Pozuelo; A. Gauchía; B. L. Boada; V. Díaz

    2009-01-01

    \\u000a Abstract  The warping of brake discs and ovality of brake drums is one of the main causes of vibration and noise during the braking\\u000a of a vehicle and of diminishing brake efficiency. Nowadays, the International Motor Vehicle Inspection Committee (CITA) demands\\u000a an inspection of the warping and ovality during the Periodic Motor Vehicle Inspection (PMVI). However, the measurement is\\u000a not always

  2. Vehicle Lateral Control and Yaw Stability Control through Differential Braking

    Microsoft Academic Search

    Chenming Zhao; Weidong Xiang; P. Richardson

    2006-01-01

    This paper examines the effectiveness of a brake-by-wire system with the uses of differential brake torque for lateral control and yaw stability control in the context of intelligent vehicle highway systems. Differential braking easily realized by the brake-by-wire system can generate the vehicle yaw moment. The resulting yaw moment affects vehicle lateral position and yaw rate, thereby providing a limited

  3. A mechatronic conception of a new intelligent braking system

    Microsoft Academic Search

    G. L Gissinger; C Menard; A Constans

    2003-01-01

    This paper describes a new intelligent braking system for motor vehicles. A mechatronic approach helped to avoid some of the drawbacks found in conventional systems. The brake was designed according to the so-called “full contact disc brake” principle, which means that the classic pads are replaced by the whole discs and that—for maximum performance—the brake is controlled continuously and not

  4. Power conditions and control of a regenerative brake

    Microsoft Academic Search

    Vladimir Blasko

    1998-01-01

    Braking capability is typically accomplished by adding a dynamic\\/resistive brake (DB) module to a standard drive. Regenerating energy is dissipated in the braking resistor creating heat and decreasing the overall efficiency of the drive. To overcome the shortcomings of the DB solution, a regenerative brake (RB) was developed. The RB is a stand-alone, add-on unit to the drive. It operates

  5. Car brake system modeling for longitudinal control design

    Microsoft Academic Search

    G. Celentano; R. Iervolino; S. Porreca; V. Fontana

    2003-01-01

    The brake system is one of the most critical car sub-systems for what concerns safety issues. Modern automobiles are equipped with anti-lock braking systems (ABS), which have improved passengers and driver security by automatically adjusting the braking force during braking in potentially dangerous conditions. For model-based control design techniques of ABS algorithms, satisfactory improvements may be achieved if a sufficiently

  6. Brake squeal: Linear and nonlinear numerical approaches

    NASA Astrophysics Data System (ADS)

    Massi, Francesco; Baillet, Laurent; Giannini, Oliviero; Sestieri, Aldo

    2007-08-01

    "Brake squeal" groups a large set of high-frequency sound emissions from brake systems. They are generated during the braking phase and are characterized by a harmonic spectrum. The onset of squeal is due to an unstable behaviour occurring in linear conditions during the braking phase, and a general approach used by several authors to determine the system instabilities is the complex eigenvalues analysis. When the brake begins to squeal, the response of the system reaches a new limit cycle where the linear models cannot be used anymore. This paper presents the integration of two different numerical procedures to identify the mechanism bringing to squeal instability and to analyse its dynamics. The first approach is a finite element modal analysis of the brake system and is used to identify its eigenvalues and to relate them to the squeal occurrence. The second one is a specific finite element programme, Plast3, appropriate for nonlinear dynamic analyses in the time domain and is particularly addressed to study contact problems with friction between deformable bodies. This programme computes the contact stresses and permits to determine the dynamics of the system along the contact surface, both in the linear and nonlinear fields. The two models are compared and the onset of squeal is predicted both in the frequency domain by the linear model and in the time domain by the nonlinear one. The instability predictions, obtained by the two models, are discussed. To simplify the dynamics of its components, the study is carried out on a simple model, made of a disc, a small friction pad and a beam supporting the pad. The geometry of the model is related to an experimental set-up used to validate the models and to compare the numerical results with the experiments.

  7. Predictive model of squeal noise occurring on a laboratory brake

    Microsoft Academic Search

    Oliviero Giannini; Aldo Sestieri

    2006-01-01

    This paper on brake squeal instability presents a reduced order model of a laboratory brake considered in a previous paper, and presents a description of the squeal mechanism occurring during experiments.The model uses the modal parameters of the laboratory brake components, the disc and the caliper, when they are not in contact between them. Successively, the caliper and the disc

  8. Multidisciplinary design optimization of an automotive magnetorheological brake design

    E-print Network

    Park, Edward

    : Magnetorheological fluid; Automotive brake; Finite element analysis; Computational fluid dynamics; Multidisciplinary This paper presents the development of a new electromechanical brake system using magnetorheological (MR) fluid. The proposed brake system consists of rotating disks immersed in a MR fluid and enclosed

  9. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 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...

  10. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 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...

  11. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...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...

  12. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 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...

  13. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...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...

  14. 49 CFR 238.315 - Class IA brake test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Class IA brake test. 238.315 Section 238...Passenger Equipment § 238.315 Class IA brake test. (a) Except as provided...this section, either a Class I or a Class IA brake test shall be performed:...

  15. 49 CFR 238.315 - Class IA brake test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Class IA brake test. 238.315 Section 238...Passenger Equipment § 238.315 Class IA brake test. (a) Except as provided...this section, either a Class I or a Class IA brake test shall be performed:...

  16. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 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...

  17. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 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...

  18. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...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...

  19. Eddy Current Brakes for Haptic Interfaces: Design, Identification, and Control

    Microsoft Academic Search

    Andrew H. C. Gosline; Vincent Hayward

    2008-01-01

    We describe the design of an eddy current brake for use as programmable viscous damper for haptic interfaces. Unlike other types of programmable brakes, eddy current brakes can provide linear, programmable physical damping that can be modulated at high frequency. These properties makes them well suited as dissipative actuators for haptic interfaces. We overview the governing physical relationships, and describe

  20. Evaluation of Disc Brake Materials for Squeal Reduction

    Microsoft Academic Search

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

    2011-01-01

    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

  1. Regenerative braking system for a hybrid electric vehicle

    Microsoft Academic Search

    S. R. Cikanek; K. E. Bailey

    2002-01-01

    This paper discusses a regenerative braking system (RBS) for a parallel hybrid electric vehicle (PHEV) that performs regenerative energy recovery based on vehicle attributes, thereby providing improved performance, efficiency and reliability at minimal additional cost. A detailed description of the regenerative braking algorithm is presented along with simulation results from a dynamic model of the PHEV exhibiting the regenerative braking

  2. Development and modelling of an electropneumatic brake system

    Microsoft Academic Search

    P. Karthikeyan; Shankar C. Subramanian

    2009-01-01

    The brake system is the primary system in an automobile which ensures its safety on the road. The ideal brake system should operate with the least effort from the driver and should stop the vehicle within the minimum possible distance. This paper deals with the air brake system which is widely used in commercial vehicles such as trucks, buses and

  3. Development of co-operative control algorithm for parallel HEV with electric booster brake during regenerative braking

    Microsoft Academic Search

    Jungwook Kim; Sungyeon Ko; Gaeun Lee; Hoon Yeo; Pilgu Kim; Hyunsoo Kim

    2011-01-01

    In this study, a co-operative regenerative braking control algorithm for the HEV with an electric booster brake was proposed and its performance was evaluated. A dynamic model for the electric booster brake system was derived to develop the electric booster brake performance simulator and its performance was investigated. In addition, a dynamic model for the 6-speed AT-based hybrid vehicle was

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

    NASA Astrophysics Data System (ADS)

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

    2010-09-01

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

  5. The design of aircraft brake systems, employing cooling to increase brake life

    NASA Technical Reports Server (NTRS)

    Scaringe, R. P.; Ho, T. L.; Peterson, M. B.

    1975-01-01

    A research program was initiated to determine the feasibility of using cooling to increase brake life. An air cooling scheme was proposed, constructed and tested with various designs. Straight and curved slotting of the friction material was tested. A water cooling technique, similar to the air cooling procedure, was evaluated on a curved slotted rotor. Also investigated was the possibility of using a phase-change material within the rotor to absorb heat during braking. Various phase-changing materials were tabulated and a 50%, (by weight) LiF - BeF2 mixing was chosen. It was shown that corrosion was not a problem with this mixture. A preliminary design was evaluated on an actual brake. Results showed that significant improvements in lowering the surface temperature of the brake occurred when air or water cooling was used in conjunction with curved slotted rotors.

  6. Hydraulic clutch

    SciTech Connect

    Ohkubo, M.

    1986-11-18

    This patent describes a hydraulic clutch comprising: an input member, an output member rotatable coaxially with the input member; friction means provided between the input and output members for selectively engaging and disengaging the members from each other; an annular hydraulic piston slidably mounted on one of the members for selectively actuating the friction means, and having an axially directed back face and an annular coned disc spring interposed between the piston and the friction means, the spring having a radially inner peripheral end, a radially outer peripheral end, and a piston-contacting portion radially intermediate inner and outer peripheral ends. The inner peripheral end is supported on the piston-mounting member at a position apart from the piston, the spring having a cross-sectional shape such that the piston contacting portion is axially closest to the back face of the piston relative to both the inner peripheral end and the outer peripheral end. The piston-contacting portion move gradually radially outwardly with increasing contact pressure by the piston.

  7. Measurements of radio pulsar braking indices

    NASA Astrophysics Data System (ADS)

    Chukwude, A. E.; Baiden, A. A.; Onuchukwu, C. C.

    2010-06-01

    A quantitative analysis of radio pulsar timing noise is presented. Our analysis employs the recently reported strong correlation (with correlation coefficient r = 0.95) between the observed second time derivative of the pulse rotation frequency (ddot?obs), obtained from fully phase-coherent timing analyses, and a timing noise statistic (?R23), used to quantify the amount of pulsar rotational fluctuations absorbed by the coefficient of the cubic term, to isolate the presumed deterministic braking index from the effects attributable to pulsar timing activity. Application of this method to a sample of 27 radio pulsars, whose timing data span 9-13 years, reveals that (i) for 22 pulsars, a sensible braking index measurement was impossible: with numerical values of the braking index either appreciably less than the corresponding uncertainty or anomalously large; (ii) save for the relatively large uncertainties, the braking index appears to be significantly measured in five pulsars. Current results are discussed in the context of the prevailing standard model for radio pulsar spin-down.

  8. A parametric study of perforated muzzle brakes

    Microsoft Academic Search

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

    1993-01-01

    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

  9. Coordinated control for regenerative braking system

    Microsoft Academic Search

    Zhang Junzhi; Lu Xin; Chen Shanglou; Zhang Pengjun

    2008-01-01

    This paper presents a design of regenerative braking system (RBS) for hybrid electric vehicles using hierarchical control structure and method. The hierarchical model is mainly composed of three modules for driver intent identification, energy management and coordinated control based on components control. As a consequence, RBS, a complicated hybrid dynamic system, is successfully decomposed by several simple modules. The control

  10. Modeling regenerative braking and storage for vehicles

    Microsoft Academic Search

    F. Wicks; K. Donnelly

    1997-01-01

    The fuel saving benefits of regenerative braking and storage for vehicles are often described but not quantified. For example, the federal government and automobile manufacturers are sponsoring a Program for a New Generation of Vehicles (PGNV) with a goal of obtaining a performance of 80 mpg in a family size car. It is typically suggested that such a vehicle will

  11. Cutting vehicle emissions with regenerative braking

    Microsoft Academic Search

    Peter Clarke; Tariq Muneer; Kevin Cullinane

    2010-01-01

    This paper presents an analysis of vehicle regenerative braking systems as a quick and relatively easy means of achieving higher overall fuel efficiency and lowering carbon emissions. The system involves the installation of an additional electric motor\\/generator in parallel to the vehicle’s internal combustion engine and is used in conjunction with a DCDC converter and ultracapacitor. The system is used

  12. Fuzzy Automated Braking System for Collision Prevention

    Microsoft Academic Search

    Piero P. Bonissone; Kareem S. Aggour

    2001-01-01

    Many automobile accidents could be avoided if the correct amount of brake pressure had been applied at the proper time. In this paper we propose the use of a fuzzy control system that could be embedded in an automobile to remove the driver's reaction time from the situation. The system, consisting of two fuzzy controllers connected in cascade, analyzes possible

  13. Use of elastomers in regenerative braking systems

    NASA Astrophysics Data System (ADS)

    The storage of potential energy as strain energy in elastomers was investigated. The evolution of the preferred stressing scheme is described, and test results on full-size elastomeric energy storage units sized for an automotive regenerative braking system application are presented. The need for elastomeric material improvements is also discussed.

  14. Adaptive brake warning system for automobiles

    Microsoft Academic Search

    P. Thammakaroon; P. Tangamchit

    2008-01-01

    We present an adaptive brake warning system in order to help a driver keep a safe distance from the cars in front to avoid rear-end collisions. The safe distance continuously varies according to the carpsilas velocity, driving events, and road conditions. Three sensors, an ECU reader, a camera, and a laser range finder, are used to collect the vehicular velocity,

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

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

    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.

  16. Analysis Of The Friction Brake Lining Including Heat Transfer System And Thermal Analysis

    Microsoft Academic Search

    Osman KOÇ

    2009-01-01

    Kinetic energy during braking of the moving mass is converted into heat energy through friction. This heat energy cause brake pads to be exposed to excessive temperature. The breaking efficiency reduces in time and in this case some problems (reducing in brake performance, defect run ning, rapid brake pad wear and noise) occur. Five different brake pad materials were subjected

  17. Effect of lateral run-out on calliper drag in automotive disc brakes

    Microsoft Academic Search

    S. H. Masood; Lakhwinder Singh

    2007-01-01

    Efficiency of an automotive disc brake system is affected by several factors such as lateral run out (LRO), caliper housing stiffness, lining compressibility, seal\\/groove design, brake fluid, and pad material. A minor deviation in any of these factors may lead to problems like brake noise, vibration and off-brake caliper drag in the brake system. This paper presents an experimental study

  18. 49 CFR 238.15 - Movement of passenger equipment with power brake defects.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...power brake defect at the time a Class I or IA brake test is performed. Except as provided...become defective en route after a Class I or IA brake test was performed), a commuter...brake defect at the time that a Class I or IA brake test (or, for Tier II trains,...

  19. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Steering axle brakes. The brake lining/pad thickness on the steering axle...drum brakes. The steering axle brake lining/pad thickness shall not be less than...vehicle shall not be operated with brake lining/pad thickness less than 6.4...

  20. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Steering axle brakes. The brake lining/pad thickness on the steering axle...drum brakes. The steering axle brake lining/pad thickness shall not be less than...vehicle shall not be operated with brake lining/pad thickness less than 6.4...

  1. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Steering axle brakes. The brake lining/pad thickness on the steering axle...drum brakes. The steering axle brake lining/pad thickness shall not be less than...vehicle shall not be operated with brake lining/pad thickness less than 6.4...

  2. Speed gradient approach to longitudinal control of heavy-duty vehicles equipped with variable compression brake

    Microsoft Academic Search

    Maria Druzhinina; Anna G. Stefanopoulou; Lasse Moklegaard

    2002-01-01

    This paper considers a longitudinal speed control problem for heavy-duty vehicles equipped with variable compression brake. The use of compression brake reduces the wear of the conventional friction brakes, and it is a preferred way of controlling the vehicle speed during a steady descent or non-critical braking maneuvers. To perform more aggressive braking maneuvers or control vehicle speed during large

  3. A novel brake control strategy for electric vehicles based on slip trial method

    Microsoft Academic Search

    Zhou Lei; Luo Yugong; Yang Diange; Li Keqiang; Lian Xiaomin

    2007-01-01

    Regenerative braking plays an important role in improving the efficiency of electric vehicles. But excessive regenerative torque may affect the anti-lock brake control. The paper presents a novel brake control strategy for electric vehicles which integrates the regenerative brake control and anti-lock brake control. The strategy is designed based on a novel idea called \\

  4. Optimal brake torque distribution for a four-wheeldrive hybrid electric vehicle stability enhancement

    Microsoft Academic Search

    D-H Kim; J-M Kim; S-H Hwang; H-S Kim

    2007-01-01

    Vehicle stability control logic for a four-wheel-drive hybrid electric vehicle is proposed using the regenerative braking of the rear motor and an electrohydraulic brake (EHB). To obtain the optimal brake torque distribution between the regenerative braking and the EHB torque, a genetic algorithm is used. The genetic algorithm calculates the optimal regenerative braking torque and the optimal EHB torque for

  5. Modeling and simulation of automobile braking system based on kinetic energy conversion

    Microsoft Academic Search

    Wenjuan Li; Xudong Wang; Xue Leng; Meng Wang

    2008-01-01

    Fatal traffic accidents are related with the overlength braking distance and sideslip when the automobile is braked in an emergency. It is very important to study and improve the braking ability of the automobile. The anti-lock braking system (ABS) is the active method of increasing the braking ability. The ABS controller is the key to ABS. The modeling and simulation

  6. Composite hydraulic system

    SciTech Connect

    Williamson, W.A.

    1987-03-17

    A composite hydraulic system is described for a work vehicle having an implement hydraulic circuit and a steering hydraulic circuit comprising a first pump which supplies the implement hydraulic circuit primarily, a second pump which supplies the steering hydraulic circuit primarily, a third pump which is operable also as a motor and which transfers hydraulic fluid between the implement and the steering hydraulic circuits, an engine which operates the three pumps simultaneously, and servo system means whereby the third pump under at least one condition of operation operates as a motor to provide regeneration.

  7. Brake and speed responsive controlled transmission

    SciTech Connect

    Maezono, M.; Shimizu, T.; Ishikawa, K.

    1987-02-24

    A control apparatus is described for multi-speed, oil pressure operated vehicle transmission having an oil pressure operated clutch for each speed drive train, a lowest and a highest speed drive train, and a one-way clutch in the lowest speed drive train. The apparatus comprises means for detecting a brake actuated condition and a stopped condition of the vehicle including means responsive to the throttle opening and governor of the vehicle engine. It also includes means responsive to the detecting means for supplying oil pressure to the clutch for the highest speed drive train during the continuance of either the brake actuated or stopped vehicle condition for minimizing the torque transmitted through the transmission.

  8. Wind turbine trailing edge aerodynamic brakes

    SciTech Connect

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

    1995-04-01

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

  9. Hydraulic pump

    SciTech Connect

    Polak, P.R.; Jantzen, D.E.

    1984-05-15

    This invention relates to an improved pump jack characterized by a hollow piston rod which telescopes down over the sucker rod to which it is clamped for reciprocating motion. The cylinder, in turn, is fastened in fixed position directly to the upper exposed end of the well casing. As fluid is introduced into the lower end of the cylinder it raises the piston into engagement with a pushrod housed in the upper cylinder head that lifts switch-actuating means associated therewith into a position operative to actuate a switch located adjacent thereto thereby causing the latter to change state and actuate a multi-function solenoid valve so as to cut off fluid flow to the cylinder. As gravity lowers the sucker rod and piston exhausting the hydraulic fluid therebeneath, an adjustable stop engages the pushrod from above so as to return it together with the switch-actuating means associated therewith to their original positions thereby resetting the switch to complete the operating cycle.

  10. Magnetic braking of the Earth's rotation

    Microsoft Academic Search

    Henry Oman

    1989-01-01

    The Earth's rotation is decelerating at a rate of 8.8×10 exp-20 rad\\/s. Thus, a leap second is added to the year every two to four years. This deceleration is small, but the Earth weighs 6×10 exp 24 kg. A prony brake that achieves this deceleration would release 5.14×10 exp 11 kW, the equivalent of 514,000 1-GW nuclear power plants. Tides,

  11. Evaluation of Corrosion Failure in Tractor-Trailer Brake System

    Microsoft Academic Search

    2002-01-01

    As reported to ORNL, concomitant with the introduction of different deicing and anti-icing compounds, there was an increase in the brake failure rate of tractor-trailer trucks. A forensic evaluation of a failed brake system was performed. Optical and scanning electron microscopic evaluation showed corrosion to be mostly confined to the brake table\\/lining interface. The corrosion is non-uniform as is to

  12. Predicting the Braking Indices of Nulling and Intermittent Pulsars

    NASA Astrophysics Data System (ADS)

    Rusul, Abdujappar; Zheng, Xiao-Ping; Esamdin, Ali

    2014-04-01

    The braking index is an important factor when examining the pulsar braking mechanism. Measuring braking indices requires measuring the pulsar period and its first and second derivatives. Among them, the second derivative is easily contaminated by timing noise and an unresolved glitch effect. The absence of data bounding a given transition into (or out of) a radio-on phase is another disadvantage in measuring the second derivatives of intermittent pulsars, as was recently demonstrated by Young and coworkers. But, the observed period first derivatives, in the "on" and "off" states of the intermittent pulsars, give us a possible way to predict their braking indices even though they are hard to observe. In this paper, we will give a simple and useful method to study the braking indices of intermittent pulsars. As an application of our method, we will calculate the possible braking indices of three intermittent pulsars and one nulling pulsar, namely, PSR B1931 + 24, PSR J1841 - 0500, PSR J1832 + 0029 and PSR B0823 + 26, under three different magnetospheric conditions, which include polar cap size variation, charge density variation and the combination of the above two cases. We have found that all the braking indices we predicted are almost within the observed domain. It is concluded that, in a relatively short observation period, in which the variation of the braking index can be ignored, we can accurately predict the braking indices of intermittent pulsars, under a specific magnetosphere model, by using the observed "on" and "off" state period first derivatives.

  13. Evaluation of materials and design modifications for aircraft brakes

    NASA Technical Reports Server (NTRS)

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

    1975-01-01

    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 utilizing a disk brake and wheel half from a small het aircraft. The apparatus enabled control of brake pressure, velocity, and braking time. Tests were run under both constant and variable velocity conditions and covered a kinetic energy range similar to that encountered in aircraft brake service. The results of the design evaluation program showed that some improvement in brake performance can be realized by making design changes in the components of the brake containing friction material. The materials evaluation showed that two friction materials show potential for use in aircraft disk brakes. One of the materials is a nickel-based sintered composite, while the other is a molybdenum-based material. Both materials show much lower wear rates than conventional copper-based materials and are better able to withstand the high temperatures encountered during braking. Additional materials improvement is necessary since both materials show a significant negative slope of the friction-velocity curve at low velocities.

  14. Fall during a wheelchair transfer: a case of mismatched brakes.

    PubMed

    Kirby, R L; Smith, C

    2001-04-01

    We report the case of a patient who had a transtibial amputation and whose wheelchair had been inadvertently fitted with a push-to-lock brake on one side and a pull-to-lock brake on the other. During a standing-pivot transfer from bed to wheelchair, during which the patient thought that she had applied both brakes, the wheelchair turned away from the patient toward the side of the unlocked brake and the patient fell to the floor. This case report has implications for wheelchair design, wheelchair system management, and for user training. PMID:11277138

  15. 49 CFR 236.554 - Rate of pressure reduction; equalizing reservoir or brake pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Rate of pressure reduction; equalizing reservoir or brake pipe. 236.554 Section 236... Rate of pressure reduction; equalizing reservoir or brake pipe. The equalizing-reservoir pressure or brake-pipe pressure...

  16. 49 CFR 236.554 - Rate of pressure reduction; equalizing reservoir or brake pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Rate of pressure reduction; equalizing reservoir or brake pipe. 236.554 Section 236... Rate of pressure reduction; equalizing reservoir or brake pipe. The equalizing-reservoir pressure or brake-pipe pressure...

  17. 49 CFR 236.554 - Rate of pressure reduction; equalizing reservoir or brake pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Rate of pressure reduction; equalizing reservoir or brake pipe. 236.554 Section 236... Rate of pressure reduction; equalizing reservoir or brake pipe. The equalizing-reservoir pressure or brake-pipe pressure...

  18. 49 CFR 232.609 - Handling of defective equipment with ECP brake systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Handling of defective equipment with ECP brake systems. 232.609 Section 232.609 Transportation...DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER...Electronically Controlled Pneumatic (ECP) Braking Systems § 232.609 Handling of...

  19. 49 CFR 232.609 - Handling of defective equipment with ECP brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Handling of defective equipment with ECP brake systems. 232.609 Section 232.609 Transportation...DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER...Electronically Controlled Pneumatic (ECP) Braking Systems § 232.609 Handling of...

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Handling of defective equipment with ECP brake systems. 232.609 Section 232.609 Transportation...DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER...Electronically Controlled Pneumatic (ECP) Braking Systems § 232.609 Handling of...

  1. 49 CFR 232.609 - Handling of defective equipment with ECP brake systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Handling of defective equipment with ECP brake systems. 232.609 Section 232.609 Transportation...DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER...Electronically Controlled Pneumatic (ECP) Braking Systems § 232.609 Handling of...

  2. 49 CFR 232.503 - Process to introduce new brake system technology.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...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...

  3. 49 CFR 232.503 - Process to introduce new brake system technology.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...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...

  4. 49 CFR 232.503 - Process to introduce new brake system technology.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...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...

  5. 49 CFR 232.503 - Process to introduce new brake system technology.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...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...

  6. 49 CFR 232.503 - Process to introduce new brake system technology.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...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...

  7. Optimal design of a novel configuration of MR brake with coils placed on the side housings

    NASA Astrophysics Data System (ADS)

    Nguyen, Quoc Hung; Nguyen, Ngoc Diep; Choi, Seung-Bok

    2014-03-01

    It is well known that in design of traditional magneto-rheological brake (MRB), coils are placed on the cylindrical housing of the brake. In this study, a new configuration of MR brake with coils placed on the side housings of the brake is proposed and analyzed. After briefly explaining the operating principle of the proposed configuration, the braking torque of the MR brake is analyze based on Bingham-plastic rheological model of MR fluid. The optimization of the proposed and conventional MR brakes is then performed considering maximum braking torque and mass of the brake. Based on the optimal results, a comparison between the proposed MR brakes and the conventional ones is undertaken. In addition, experimental test of the MR brakes is conducted and the results are presented in order to validate the performance characteristics of the proposed MR brake.

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

    Microsoft Academic Search

    Datong Qin; Ming Ye; Zhenjun Liu

    2007-01-01

    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.

  9. A study on regenerative braking for a parallel hybrid electric vehicle

    Microsoft Academic Search

    Sungwook Jang; Hoon Yeo; Chulsoo Kim; Hyunsoo Kim

    2001-01-01

    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

  10. Copper leaching from brake wear debris in standard extraction solutions.

    PubMed

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

    2003-10-01

    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

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

    NASA Astrophysics Data System (ADS)

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

    2009-06-01

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

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

    Microsoft Academic Search

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

    2011-01-01

    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

  13. Surface modification of brake discs to reduce squeal problems

    Microsoft Academic Search

    Lars Hammerström; Staffan Jacobson

    2006-01-01

    Noise and squeal from brakes is a problem in the automotive industry and large efforts are made to reduce the squeal tendencies. The approach taken is mainly to improve the design of the caliper, to fine-tune the brake pad material and finally to trim by introducing shims on the backside of the pads. Despite these efforts still no general solutions

  14. Judder vibration in disc brakes excited by thermoelastic instability

    Microsoft Academic Search

    Oscar Altuzarra; Enrique Amezua; Rafael Avilés; Alfonso Hernández

    2002-01-01

    Friction vibrations and noises which are common in brakes, have attracted a great deal of attention lately. This paper analyses low frequency vibrations in disc brakes excited at high car speed. This vibration, called judder, has a frequency in the range 10 to 300 Hz and usually comes in association with hum noises. The dynamic phenomenon shows two principal components,

  15. Thermally induced roughness of tread-braked railway wheels

    Microsoft Academic Search

    T Vernersson

    1999-01-01

    Roughness (corrugation, waviness) on the tread of a rolling railway wheel leads to vibrations in wheels, bogies and superstructure and also in rails, sleepers and roadbed. These vibrating components radiate noise to the surroundings. A lowering of the noise levels from tread-braked freight cars is of utmost importance for the future of rail traffic. The thermomechanical interaction between brake block

  16. STABILITY ANALYSIS OF DISC BRAKE SQUEAL CONSIDERING TEMPERATURE EFFECT

    Microsoft Academic Search

    Abd Rahim; Abu Bakar; Mohd Kameil Abdul Hamid; Afandi Dzakaria; Badri Abdul Ghani; Maziah Mohamad

    2006-01-01

    Passenger cars have become one of the main transportations for people travelling from one place to another. Indeed, vehicle quietness and passenger comfort issues are a major concern. One of vehicle components that occasionally generate unwanted vibration and unpleasant noise is the brake system. Brake squeal noise is the most troublesome and irritant one to both car passenger and the

  17. Thermally induced roughness of tread braked railway wheels

    Microsoft Academic Search

    T. Vernersson

    1999-01-01

    Roughness (corrugation, waviness) on the tread of a rolling railway wheel leads to vibrations in wheels, bogies and superstructure and also in rails, sleepers and roadbed. These vibrating components radiate noise to the surroundings. A lowering of the noise levels from tread braked freight cars is of utmost importance for the future of rail traffic. The thermomechanical interaction between brake

  18. Suppression of Brake Squeal Noise Applying Viscoelastic Damping Insulator

    Microsoft Academic Search

    Jun Hou; Xuexun Guo; Guohui Sun; Jie Zhang

    2009-01-01

    Squeal noise in vehicle disc brakes is perceived by consumers as both annoying and warranty cost. Among the methods that have been used to control squeal noise, increasing the system damping has been shown to be very effective. The most commonly used method to increase system damping consists of attaching multi-layer laminates on the back of the brake pads. As

  19. A diagnostic system for air brakes in commercial vehicles 

    E-print Network

    Coimbatore Subramanian, Shankar Ram

    2007-09-17

    to maintenance and hence they require frequent inspections. Current inspection techniques require an inspector to go underneath a vehicle to check the brake system for possible faults, such as leaks, worn brake pads, out-of-adjustment of push rods, etc...

  20. A pressure control scheme for air brakes in commercial vehicles 

    E-print Network

    Bowlin, Christopher Leland

    2007-04-25

    This research is focused on developing a control scheme for regulating the pressure in the brake chamber of an air brake system found in most commercial vehicles like trucks, tractor-trailers and buses. Such a control scheme can be used...

  1. Electric propulsion and braking system for automotive vehicles

    Microsoft Academic Search

    Preikschat

    1982-01-01

    An electric propulsion and braking system which includes a plurality of high-speed, dc commutatorless motors each coupled to a wheel of an automotive vehicle through an associated fixedratio mechanical transmission. Each motor includes a field winding, an armature winding, and a commutation circuit for the armature winding. During propulsion, each commutation circuit is enabled and, during braking, each commutation circuit

  2. On the nature of tribological contact in automotive brakes

    Microsoft Academic Search

    Mikael Eriksson; Filip Bergman; Staffan Jacobson

    2002-01-01

    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

  3. Metal-bending brake facilitates lightweight, close-tolerance fabrication

    NASA Technical Reports Server (NTRS)

    Ercoline, A. L.; Wilton, K. B.

    1964-01-01

    A lightweight, metal bending brake ensures very accurate bends. Features of the brake that adapt it for making complex reverse bends to close tolerances are a pronounced relief or cutaway of the underside of the bodyplate combined with modification in the leaf design and its suspension.

  4. Compressed gas system operates semitrailer brakes during winching operation

    NASA Technical Reports Server (NTRS)

    Tupper, W. E.

    1964-01-01

    To move van-type semi-trailers into and out of confined spaces, an auxiliary braking system is mounted on a standard dolly converter. Compressed nitrogen is used to actuate the brakes which are used in conjunction with a power winch.

  5. Motion Control of Passive Intelligent Walker Using Servo Brakes

    Microsoft Academic Search

    Yasuhisa Hirata; Asami Hara; Kazuhiro Kosuge

    2007-01-01

    We propose a new intelligent walker based on passive robotics that assists the elderly, handicapped people, and the blind who have difficulty in walking. We developed a prototype of the robot technology walker (RT walker), a passive intelligent walker that uses servo brakes. The RT walker consists of a support frame, two casters, two wheels equipped with servo brakes, and

  6. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...procedure. Insert a low range (0 to 25 amperes for most 2- and 4-brake systems and 0 to 40 amperes for a 6-brake system) d.c. ammeter into...full off” and observe return to zero amperes. Divide the maximum ammeter reading...

  7. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...procedure. Insert a low range (0 to 25 amperes for most 2- and 4-brake systems and 0 to 40 amperes for a 6-brake system) d.c. ammeter into...full off” and observe return to zero amperes. Divide the maximum ammeter reading...

  8. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...procedure. Insert a low range (0 to 25 amperes for most 2- and 4-brake systems and 0 to 40 amperes for a 6-brake system) d.c. ammeter into...full off” and observe return to zero amperes. Divide the maximum ammeter reading...

  9. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...procedure. Insert a low range (0 to 25 amperes for most 2- and 4-brake systems and 0 to 40 amperes for a 6-brake system) d.c. ammeter into...full off” and observe return to zero amperes. Divide the maximum ammeter reading...

  10. Jumps and Synchronization in Anti-lock Brake Algorithms

    E-print Network

    Paris-Sud XI, Université de

    : Traction and Brake Control, Tire Property, Modeling and Simulation Technology. INTRODUCTION conditions, tyre pressure, tem- perature, etc. They should thus be assumed to be unknown. 1.2 Wheel velocity will assume that during ABS braking the clutch pedal is kept en- gaged, and thus neglect the engine torque. 1

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

    DOEpatents

    Norgren, Duane U. (Orinda, CA)

    1984-01-01

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

  12. 49 CFR 238.313 - Class I brake test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...apply and remain applied on each car in the train until a release of...brakes has been initiated on each car in response to train line electric, pneumatic, or other signals...verification that each side of each car's brake system responds...

  13. 49 CFR 238.313 - Class I brake test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...apply and remain applied on each car in the train until a release of...brakes has been initiated on each car in response to train line electric, pneumatic, or other signals...verification that each side of each car's brake system responds...

  14. 49 CFR 238.313 - Class I brake test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...apply and remain applied on each car in the train until a release of...brakes has been initiated on each car in response to train line electric, pneumatic, or other signals...verification that each side of each car's brake system responds...

  15. ORNL/Pub40701 Heavy and Overweight Vehicle Brake

    E-print Network

    ORNL/Pub40701 Heavy and Overweight Vehicle Brake Testing: Combination Five-Axle Tractor- Flatbed and Transportation Science Division HEAVY AND OVERWEIGHT VEHICLE BRAKE TESTING: COMBINATION FIVE-AXLE TRACTOR .................................................................................1 1.3 PURPOSE OF TRACTOR-FLATBED TESTING

  16. Method and apparatus for braking a derrick winch

    SciTech Connect

    Falcon, J.F.

    1989-09-12

    This patent describes an apparatus for braking a derrick winch with a winch brake. It comprises: a control lever remotely located from the winch; a servo-control circuit connecting the lever and brake for actuating the brake in response to movement of the lever, and including: a torque motor having a shaft mechanically coupled to the control lever; a brake activating device for actuating the winch brake; a first position transducer for sensing the position of the control lever; a second position transducer for sensing the position of the winch brake; a first force transducer for measuring the force applied to the winch brake; a first comparator; a second comparator. The first comparator being connected to receive signals from the first and second position transducers and to deliver an error signal to the torque motor and to the second comparator. The second comparator being connected to receive signals from the first comparator and from the first force transducer and to deliver an error signal to the actuating device.

  17. Research on control for regenerative braking of electric vehicle

    Microsoft Academic Search

    Binggang Cao; Zhifeng Bai; Wei Zhang

    2005-01-01

    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

  18. Hydraulic dynamic analysis

    NASA Technical Reports Server (NTRS)

    Gale, R. L.; Nease, A. W.; Nelson, D. J.

    1978-01-01

    Computer program mathematically describes complete hydraulic systems to study their dynamic performance. Program employs subroutines that simulate components of hydraulic system, which are then controlled by main program. Program is useful to engineers working with detailed performance results of aircraft, spacecraft, or similar hydraulic systems.

  19. Eigenvalue optimization against brake squeal: Symmetry, mathematical background and experiments

    NASA Astrophysics Data System (ADS)

    Spelsberg-Korspeter, Gottfried

    2012-09-01

    Brake squeal is still a challenge for design engineers and scientists. Due to cost reasons for the avoidance of brake noise only passive measures are meaningful for a broad industrial range. Many countermeasures against squeal are based on the introduction of damping, for example by using shims. In the literature on the modeling of brake squeal, the structural properties of the brake disc are most often not considered. It has however been shown analytically and experimentally that the stiffness properties of the disc are important and that splitting of double modes of the disc has a stabilizing effect. This knowledge can be used for structural optimization of brake rotors. The goal of this paper is to exploit the potential and to discuss some mathematical difficulties. Furthermore, experimental evidence for the relation of rotor asymmetry and squeal is given.

  20. Analysis of heat conduction in a disk brake system

    NASA Astrophysics Data System (ADS)

    Talati, Faramarz; Jalalifar, Salman

    2009-06-01

    In this paper, the governing heat equations for the disk and the pad are extracted in the form of transient heat equations with heat generation that is dependant to time and space. In the derivation of the heat equations, parameters such as the duration of braking, vehicle velocity, geometries and the dimensions of the brake components, materials of the disk brake rotor and the pad and contact pressure distribution have been taken into account. The problem is solved analytically using Green’s function approach. It is concluded that the heat generated due to friction between the disk and the pad should be ideally dissipated to the environment to avoid decreasing the friction coefficient between the disk and the pad and to avoid the temperature rise of various brake components and brake fluid vaporization due to excessive heating.

  1. Suppression of brake squeal noise applying finite element brake and pad model enhanced by spectral-based assurance criteria

    Microsoft Academic Search

    Yi Dai; Teik C. Lim

    2008-01-01

    An enhanced dynamic finite element (FE) model with friction coupling is applied to analyze the design of disc brake pad structure for squeal noise reduction. The FE model is built-up from the individual brake component representations. Its interfacial structural connections and boundary conditions are determined by correlating to a set of measured frequency response functions using a spectral-based assurance criterion.

  2. PROTOBINARY EVOLUTION DRIVEN BY MAGNETIC BRAKING

    NASA Astrophysics Data System (ADS)

    Zhao, Bo; Li, Z.; Kratter, K. M.

    2014-01-01

    The majority of stars are in multiple systems, especially binaries. Such objects form in dense cores of molecular clouds that are observed to be strongly magnetized. Most previous studies of binary formation have either ignored magnetic fields or focused on the initial core fragmentation into binary seeds. Here I focus on the effects of the magnetic field on the orbital evolution of the protobinary during the main accretion phase, after a pair of stellar seeds have formed. By simulating a 'seed' binary system with the sink particle treatment, we show that magnetic field plays a crucial role in removing the gas angular momentum and shrinking the binary separation. Through magnetic braking, strong magnetic field is very effective in suppressing the formation of circumstellar disks and circumbinary disk along with its spiral arm structures. The magnetic field can also be responsible for the population of the low mass-ratio binaries in the observed distribution. The magnetically-braked material will have equal chance of being accreted onto either binary seed, instead of the preferential accretion onto the secondary when magnetic field is absent. Furthermore, large field mis-alignment helps to produce rotationally-supported circumbinary disks even for relatively strong magnetic fields, by weakening the magnetically-dominated structure close to the binary. Hence to explain the observed properties of binaries, the magnetic effects deserve more careful considerations in the larger context of binary formation in future studies.

  3. Process Optimization for the Improvement of Brake Noise: A Case Study

    Microsoft Academic Search

    Hee Seong Sohn; Tae Won Park

    2006-01-01

    This study improves brake noise by optimizing the manufacturing processes of brake discs and pads. Taguchi techniques and designed experiments were used for the optimization. The signal-to-noise ratios of the key output responses, such as runouts of brake discs and compressibility of brake pads, were maximized to optimize the mean and variation. Analysis of the variance was performed to obtain

  4. A performance evaluation of an automotive magnetorheological brake design with a sliding mode controller

    E-print Network

    Park, Edward

    -by-wire is a techno- logical wildcard for automotive systems such as steering and braking, and means replacing with electrical components. According to [1], in the first generation of brake-of-wire systems, a conventional braking in the case of an ECU or electrical failure. In the second gen- eration brake-by-wire systems

  5. EB2013-MS-008-Paper REDUCED ORDER BRAKE MODELS TO STUDY THE EFFECT ON

    E-print Network

    Paris-Sud XI, Université de

    EB2013-MS-008-Paper REDUCED ORDER BRAKE MODELS TO STUDY THE EFFECT ON SQUEAL OF PAD REDESIGN 1. The only adjustable parameter is here the brake pad, since it is the only part with frequent replacement lifetime. The only adjustable parameter is here the brake pad, which needs frequent replacement. The brake

  6. Speed Gradient Approach to Longitudinal Control of Heavy-Duty Vehicles Equipped with Variable Compression Brake

    E-print Network

    Stefanopoulou, Anna

    Compression Brake M. Druzhinina1, L. Moklegaard and A. G. Stefanopoulou University of California, Santa Barbara Abstract Speed regulation of Heavy-Duty Vehicles equipped with variable compression brake is considered in this paper. Use of compression brake reduces the wear of the conventional friction brakes

  7. Application of a suspension rope brake to a single rope mine hoisting system

    Microsoft Academic Search

    Thomas D. Barkand

    1992-01-01

    The author discusses the application of counterweight safeties, electrical dynamic braking, and a pneumatic rope brake system to single-rope mine hoists. He considers the control, design, and testing of a suspension rope brake applied to a single-rope mine hoist. The rope brake grips the suspension ropes and stops the hoist if an overspeed of 15% is detected of if the

  8. Regenerative braking for electric vehicle based on fuzzy logic control strategy

    Microsoft Academic Search

    Zijian Zhang; Guoqing Xu; Weimin Li; Liang Zheng

    2010-01-01

    In order to recycle more energy in the process of regenerative braking, we design a regenerative braking force calculation controller based on fuzzy logic. The sugeno's interface fuzzy logic controller has three-inputs including the driver's brake requirements, vehicle speed and batteries' SOC and one-output which is the regenerative braking force. To ensure charging safety, the influence of batteries' temperature is

  9. Design and implementation of a regenerative braking system for electric bicycles based on DSP

    Microsoft Academic Search

    Chih-Chiang Hua; Shih-Jyun Kao

    2011-01-01

    This paper proposes a regenerative braking system for electric bicycle based on DSP. The proposed method is used to adjust the switching sequence of the inverter, so that the braking energy will be returned to charge the battery. With the cooperation of regenerative braking energy recovery technologies and digital signal processor (TMS320LF2407) as the control unit, the regenerative braking energy

  10. Numerical study on the vibration characteristics of automobile brake disk and pad

    Microsoft Academic Search

    Xianjie Meng; Guangqiang Wu; Lin He

    2009-01-01

    Based on the review of researches on the vibration and noise related to automobile brake, a four degrees of freedom nonlinear dynamics model of brake disk and pads is established, the stability of vibration system at the equilibrium points is analyzed. Finally the numerical method is taken to study the impacts of brake pressure, shape parameter and the brake disk's

  11. Application of creative design concept to braking system synchronization in two wheeler bikes

    Microsoft Academic Search

    S. Vinodh; M. Arun

    2010-01-01

    Purpose – The purpose of this paper is to report a research in which creative design concepts have been applied for braking system synchronization in two wheeler bikes. Design\\/methodology\\/approach – Literature review on creative design concepts and braking system scenario has been carried out. By studying the existing braking system and applying creative design concepts, modified braking system has been

  12. Nonlinear control design of anti-lock braking systems combined with active suspensions

    Microsoft Academic Search

    Wei-En Ting; Jung-Shan Lin

    2004-01-01

    This paper develops the anti-lock braking control system integrated with active suspensions applied to a quartercar model by employing the nonlinear backstepping design schemes. In emergency, although the braking distance can be reduced by the control torque from disk\\/drum brakes, the braking time and distance can be further improved if the normal force generated from active suspension systems is considered

  13. Optimal design of a hybrid MR brake for haptic wrist application

    NASA Astrophysics Data System (ADS)

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

    2011-03-01

    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.

  14. Vehicle Hybrid Braking Control Using Sliding Mode Control

    NASA Astrophysics Data System (ADS)

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

    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.

  15. EEG potentials predict upcoming emergency brakings during simulated driving.

    PubMed

    Haufe, Stefan; Treder, Matthias S; Gugler, Manfred F; Sagebaum, Max; Curio, Gabriel; Blankertz, Benjamin

    2011-10-01

    Emergency braking assistance has the potential to prevent a large number of car crashes. State-of-the-art systems operate in two stages. Basic safety measures are adopted once external sensors indicate a potential upcoming crash. If further activity at the brake pedal is detected, the system automatically performs emergency braking. Here, we present the results of a driving simulator study indicating that the driver's intention to perform emergency braking can be detected based on muscle activation and cerebral activity prior to the behavioural response. Identical levels of predictive accuracy were attained using electroencephalography (EEG), which worked more quickly than electromyography (EMG), and using EMG, which worked more quickly than pedal dynamics. A simulated assistance system using EEG and EMG was found to detect emergency brakings 130 ms earlier than a system relying only on pedal responses. At 100 km h(-1) driving speed, this amounts to reducing the braking distance by 3.66 m. This result motivates a neuroergonomic approach to driving assistance. Our EEG analysis yielded a characteristic event-related potential signature that comprised components related to the sensory registration of a critical traffic situation, mental evaluation of the sensory percept and motor preparation. While all these components should occur often during normal driving, we conjecture that it is their characteristic spatio-temporal superposition in emergency braking situations that leads to the considerable prediction performance we observed. PMID:21799241

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

    Microsoft Academic Search

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

    1998-01-01

    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

  17. Hydraulic type starting clutch

    SciTech Connect

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

    1987-07-14

    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 the input rotating member to the output rotating member; urging means interposed between the friction plates and the output rotating member for urging the friction plates to cause the transmission of torque from the input rotating member to the output rotating member; a hydraulic pressure chamber defined between the urging means and the output rotating member and disposed to be supplied with a hydraulic fluid for acting upon the urging means to urge the friction plates; a hydraulic fluid source for supplying the hydraulic fluid to the hydraulic pressure chamber; pressure regulating valve means for regulating the pressure of the hydraulic fluid in the hydraulic pressure chamber; and control means for controlling the pressure regulating valve means to regulate the pressure of the hydraulic fluid in the hydraulic pressure chamber so as to increase with an increase in the rotational speed of the input shaft, the control means.

  18. Shape, Form, And Texture Recognition For Automotive Brake Pad Inspection

    NASA Astrophysics Data System (ADS)

    Roning, Juha; Hall, E. L.

    1987-05-01

    Automated inspection is an important new technology which promises to significantly improve productivity in a variety of applications. Not only is 100% inspection becoming a possibility but also in-place rather than post-process inspection is now being used. The purpose of this paper is to present techniques for shape, form, and texture recognition for the inspection of automotive brake pads. Although the results are preliminary, they indicate the type techniques which could be applied to the inspection of millions of brake pads per year in the U.S. alone. Also, since brake pads contain asbestos, humans could be removed from a harmful environment.

  19. Design of Brake Control System on Sounding Rocket Experiment

    NASA Astrophysics Data System (ADS)

    Suzuki, Toru; Mazawa, Tomoya; Watanabe, Takeo; Fujii, Hironori A.

    One engineering experiment and two scientific experiments are scheduled by using the bare electro-dynamic tape tether on the S520 sounding rocket in 2009. Purpose of the engineering experiment is a quick deployment of tape tether stored in the box with the foldaway storage method, which is a new concept of tether deployment schemes. The design of braking control system for foldaway tape tether deployer is studied in this paper. Braking drag force is measured by experiment in vacuum condition and air, and braking drag characteristic is analyzed from these results of several kinds of experiments.

  20. Brake lock mechanism for the two axis pointing system

    NASA Technical Reports Server (NTRS)

    Posey, Alan; Clark, Mike; Mignosa, Larry

    1991-01-01

    Six months prior to shipment of the Broadband X-ray Telescope to the Kennedy Space Center for flight aboard the Space Shuttle Columbia, a major system failure occurred. During modal survey testing of the telescope's gimbal pointing system, the roll axis brake unexpectedly released. Low level vibration and static preloads present during the modal survey were within the expected flight environment. Brake release during shuttle liftoff or ascent was an unacceptable risk to mission success; thus, a Brake Lock Mechanism (BLM) was developed.

  1. Effect of Electromagnetic Brake on Decreasing Unbalanced Flow in Mold

    NASA Astrophysics Data System (ADS)

    Miki, Yuji; Furumai, Kohei

    2015-06-01

    In order to clarify the mechanism of suppression of unbalanced flow in the mold under high throughput conditions in continuous casting, the effect of using an electromagnetic brake on decreasing molten steel momentum and suppressing unbalanced flow in the mold was investigated. (1) The measured value of the effect of the electromagnetic brake on decreasing molten steel momentum was consistent with the calculated value. Molten steel momentum could be reduced by more than 50% when the Stuart number was more than 3. 5. (2) Increased mold level fluctuations caused by unbalanced flow in the mold are suppressed by applying the optimum magnetic flux density with an electromagnetic brake, even under high throughput conditions.

  2. Braking Distance Prediction by Hydroplaning Analysis of 3-D Patterned Tire Model

    Microsoft Academic Search

    Jin-Rae Cho; Joo-Hyoung Choi; Hong-Woo Lee; Jong-Shik Woo; Wan-Suk Yoo

    2007-01-01

    In this paper, we present a wet-road braking distance estimate for the vehicles equipped with ABS (Anti-lock Brake System). In order to effectively compute the interval-wise braking times and the resulting total braking distance, we divide the entire speed interval at braking into finite number of uniform sub-intervals and apply the energy conservation law to individual sub-intervals. The proposed method

  3. Effective regenerative braking control for smooth stop of a hybrid electric bus

    Microsoft Academic Search

    Jie Shu; Weiwei Xiong; Chengliang Yin; Yong Zhang

    2008-01-01

    Regenerative braking is an important function for a hybrid electric bus with many stop-to-go drive conditions. Yet an accurate nonlinear model for the composite brake system in HEV and a nonlinear model-based control design for a series-parallel hybrid electric bus have not been fully studied. This paper describes the brake system with regenerative braking function, and a special brake pedal

  4. Tribomaterial factors in space mechanism brake performance

    NASA Technical Reports Server (NTRS)

    Hawthorne, H. M.

    1990-01-01

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

  5. Electric-hydraulic car

    SciTech Connect

    Clark, R.W.; Greene, H.

    1993-07-27

    A propulsion system is described for a vehicle having a chassis and at least one drive wheel, the propulsion system including in combination: a constant speed power source comprising an alternating current electric motor operated at a constant speed corresponding to its optimum performance; a source of energy comprising a storage battery and an inverter connected to the electric motor for operating the electric motor of the constant speed power source; a hydraulic fluid system including a main hydraulic pump coupled with the electric motor of the constant speed power source and driven thereby; at least one hydraulic drive motor coupled with the hydraulic pump for receiving fluid flow therefrom; and means for varying the fluid flow through the main hydraulic pump to vary the speed of operation of the hydraulic drive motor.

  6. Hydraulic fracture design optimization

    SciTech Connect

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

    1992-06-01

    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.

  7. Hydraulic fracture design optimization

    SciTech Connect

    Advani, S.H.; Lee, T.S. [Lehigh Univ., Bethlehem, PA (United States)

    1992-05-01

    This research and development investigation, sponsored by U.S. DOE and the oil and gas industry, extends previously developed hydraulic fracture geometry models and applies 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.

  8. Hydraulic fracture design optimization

    SciTech Connect

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

    1992-01-01

    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.

  9. Regenerative braking on bicycles to power LED safety flashers

    E-print Network

    Collier, Ian M

    2005-01-01

    This work develops a method for capturing some of the kinetic energy ordinarily lost during braking on bicycles to power LED safety flashers. The system is designed to eliminate: (a) battery changing in popular LED flashers, ...

  10. 11. STOVE NUT USED IN THE MILL WHEN THE BRAKE ...

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

    11. STOVE NUT USED IN THE MILL WHEN THE BRAKE WHEEL DROVE ONE PAIR OF MILLSTONES DIRECTLY; FOUND ON THE FIRST FLOOR OF THE WINDMILL AT WATERMILL - Windmill at Water Mill, Montauk Highway & Halsey Lane, Water Mill, Suffolk County, NY

  11. 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

  12. Implementation Of Fuzzy Automated Brake Controller Using TSK Algorithm

    NASA Astrophysics Data System (ADS)

    Mittal, Ruchi; Kaur, Magandeep

    2010-11-01

    In this paper an application of Fuzzy Logic for Automatic Braking system is proposed. 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. A digital controller design was chosen which combines a fuzzy logic element and a decision logic network. The controller identifies the current road condition and generates a command braking pressure signal Depending upon the speed and distance of train. This paper describes design criteria, and the decision and rule structure of the control system. The simulation results present the system's performance depending upon the varying speed and distance of the train.

  13. Adaptive Rollover Prevention for Automotive Vehicles with Differential Braking

    E-print Network

    Duffy, Ken

    Adaptive Rollover Prevention for Automotive Vehicles with Differential Braking Selim Solmaz, switching, and tuning (MMST) paradigm [13, 14, 15] for preventing un­tripped rollover in automotive vehicles performance than its fixed robust counterpart. Keywords: Automotive control; Multiple models; Parameter

  14. 54. West emergency brake in the south machinery room (interior ...

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

    54. West emergency brake in the south machinery room (interior of both machinery rooms is identical). Facing west. - Henry Ford Bridge, Spanning Cerritos Channel, Los Angeles-Long Beach Harbor, Los Angeles, Los Angeles County, CA

  15. 49 CFR 393.42 - Brakes required on all wheels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...5) Brakes are not required on the steering axle of a three-axle dolly which is steered by a co-driver. (6) Loaded housemoving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and...

  16. 49 CFR 393.42 - Brakes required on all wheels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...5) Brakes are not required on the steering axle of a three-axle dolly which is steered by a co-driver. (6) Loaded housemoving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and...

  17. 49 CFR 393.42 - Brakes required on all wheels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...5) Brakes are not required on the steering axle of a three-axle dolly which is steered by a co-driver. (6) Loaded housemoving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and...

  18. 49 CFR 570.59 - Service brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...the surface at the thinnest point on the lining or pad. (d) Structural and mechanical parts. Backing plates, brake spiders and caliper assemblies shall not be deformed or cracked. System parts shall not be broken, misaligned, missing,...

  19. 49 CFR 570.59 - Service brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...the surface at the thinnest point on the lining or pad. (d) Structural and mechanical parts. Backing plates, brake spiders and caliper assemblies shall not be deformed or cracked. System parts shall not be broken, misaligned, missing,...

  20. 30 CFR 75.1404 - Automatic brakes; speed reduction gear.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips...Statutory Provisions] Each locomotive and haulage car used in an underground coal mine shall be equipped with...permit automatic brakes, locomotives and haulage cars...

  1. 30 CFR 75.1404 - Automatic brakes; speed reduction gear.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips...Statutory Provisions] Each locomotive and haulage car used in an underground coal mine shall be equipped with...permit automatic brakes, locomotives and haulage cars...

  2. 30 CFR 75.1404 - Automatic brakes; speed reduction gear.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips...Statutory Provisions] Each locomotive and haulage car used in an underground coal mine shall be equipped with...permit automatic brakes, locomotives and haulage cars...

  3. 30 CFR 75.1404-1 - Braking system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...1404-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips § 75.1404-1 Braking system. A locomotive equipped with a dual...

  4. 30 CFR 75.1404 - Automatic brakes; speed reduction gear.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips...Statutory Provisions] Each locomotive and haulage car used in an underground coal mine shall be equipped with...permit automatic brakes, locomotives and haulage cars...

  5. 30 CFR 75.1404-1 - Braking system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...1404-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips § 75.1404-1 Braking system. A locomotive equipped with a dual...

  6. 30 CFR 75.1404-1 - Braking system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...1404-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips § 75.1404-1 Braking system. A locomotive equipped with a dual...

  7. 30 CFR 75.1404 - Automatic brakes; speed reduction gear.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips...Statutory Provisions] Each locomotive and haulage car used in an underground coal mine shall be equipped with...permit automatic brakes, locomotives and haulage cars...

  8. 30 CFR 75.1404-1 - Braking system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...1404-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips § 75.1404-1 Braking system. A locomotive equipped with a dual...

  9. 30 CFR 75.1404-1 - Braking system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...1404-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips § 75.1404-1 Braking system. A locomotive equipped with a dual...

  10. Metals associated with stormwater-relevant brake and tire samples

    PubMed Central

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

    2009-01-01

    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. PMID:19709720

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

    E-print Network

    Lignon, Sylvain; Jezequel, Louis

    2008-01-01

    The concept of friction-induced brake vibrations, commonly known as judder, is investigated. Judder vibration is based on the class of geometrically induced or kinematic constraint instability. After presenting the modal coupling mechanism and the associated dynamic model, a stability analysis as well as a sensitivity analysis have been conducted in order to identify physical parameters for a brake design avoiding friction-induced judder instability. Next, in order to reduce the size of the instability regions in relation to possible system parameter combinations, robust stability via \\mu-synthesis is applied. By comparing the unstable regions between the initial and controlled brake system, some general indications emerge and it appears that robust stability via \\mu-synthesis has some effect on the instability of the brake system.

  12. 4. FLOOR 3; GENERAL VIEW LOOKING NORTH SHOWS WALLOWER, BRAKE ...

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

    4. FLOOR 3; GENERAL VIEW LOOKING NORTH SHOWS WALLOWER, BRAKE LEVER, CASE FOR SCREENER, TOP OF GRAIN ELEVATOR, LAYSHAFT WHICH POWERS THE SCREENER AND ELEVATOR - Hayground Windmill, Windmill Lane, East Hampton, Suffolk County, NY

  13. Performance analysis and comparision of ultracapacitor based regenerative braking system

    Microsoft Academic Search

    Tongzhen Wei; Sibo Wang; Xuhua Gao

    2009-01-01

    In this paper three types of energy storage system for regenerative braking are presented. The advantages and disadvantages are discussed after the simulation and experimental results are presented. Problems are discussed and the design guidelines are suggested.

  14. Numerical Analysis of Car Disc Brake Squeal Considering Thermal Effects

    Microsoft Academic Search

    Lijie Li; Huajiang Ouyang; A. R. AbuBakar

    Friction-induced vibration and noise emanating from car disc brakes is a source of considerable discomfort and leads to customer\\u000a dissatisfaction. The high frequency noise above 1 kHz, known as squeal, is most annoying and is very difficult to eliminate.\\u000a It was recently estimated that noise, harshness and vibration (together known as the NVH problem), including disc brake squeal,\\u000a generated warranty

  15. The T.G.V. disk brake squeal

    Microsoft Academic Search

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

    Discomfort problems due to the noise emittence of braking systems in trains have suggested recently several mechanical analyses.\\u000a This paper gives some of our results obtained from the numerical modelling of TGV brakes in relation with some experimental\\u000a data. The numerical discussion is based upon the Coulomb’s law of contact with a constant coefficient of friction. A dynamic\\u000a stability analysis

  16. ElectroMechanical Friction Disc, Ring and Drum Brakes

    Microsoft Academic Search

    B. T. Fijalkowski

    \\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,

  17. Research study on antiskid braking systems for the space shuttle

    NASA Technical Reports Server (NTRS)

    Auselmi, J. A.; Weinberg, L. W.; Yurczyk, R. F.; Nelson, W. G.

    1973-01-01

    A research project to investigate antiskid braking systems for the space shuttle vehicle was conducted. System from the Concorde, Boeing 747, Boeing 737, and Lockheed L-1011 were investigated. The characteristics of the Boeing 737 system which caused it to be selected are described. Other subjects which were investigated are: (1) trade studies of brake control concepts, (2) redundancy requirements trade study, (3) laboratory evaluation of antiskid systems, and (4) space shuttle hardware criteria.

  18. Thermoelastic analysis for chattering phenomenon of automotive disk brake

    Microsoft Academic Search

    Chongdu Cho; Sooick Ahn

    2001-01-01

    This study investigates the effects of operating conditions on the chattering of an automotive disk brake by experimental\\u000a and computational methods. Design factors, which cause chattering in automobiles, have attracted great attentions for long\\u000a time; but they are not well understood yet. For this study, we construct a brake dynamometer for measuring the disk surface\\u000a temperature during chattering, and propose

  19. Thermally Actuated Hydraulic Pumps

    NASA Technical Reports Server (NTRS)

    Jones, Jack; Ross, Ronald; Chao, Yi

    2008-01-01

    Thermally actuated hydraulic pumps have been proposed for diverse applications in which direct electrical or mechanical actuation is undesirable and the relative slowness of thermal actuation can be tolerated. The proposed pumps would not contain any sliding (wearing) parts in their compressors and, hence, could have long operational lifetimes. The basic principle of a pump according to the proposal is to utilize the thermal expansion and contraction of a wax or other phase-change material in contact with a hydraulic fluid in a rigid chamber. Heating the chamber and its contents from below to above the melting temperature of the phase-change material would cause the material to expand significantly, thus causing a substantial increase in hydraulic pressure and/or a substantial displacement of hydraulic fluid out of the chamber. Similarly, cooling the chamber and its contents from above to below the melting temperature of the phase-change material would cause the material to contract significantly, thus causing a substantial decrease in hydraulic pressure and/or a substantial displacement of hydraulic fluid into the chamber. The displacement of the hydraulic fluid could be used to drive a piston. The figure illustrates a simple example of a hydraulic jack driven by a thermally actuated hydraulic pump. The pump chamber would be a cylinder containing encapsulated wax pellets and containing radial fins to facilitate transfer of heat to and from the wax. The plastic encapsulation would serve as an oil/wax barrier and the remaining interior space could be filled with hydraulic oil. A filter would retain the encapsulated wax particles in the pump chamber while allowing the hydraulic oil to flow into and out of the chamber. In one important class of potential applications, thermally actuated hydraulic pumps, exploiting vertical ocean temperature gradients for heating and cooling as needed, would be used to vary hydraulic pressures to control buoyancy in undersea research vessels. Heretofore, electrically actuated hydraulic pumps have been used for this purpose. By eliminating the demand for electrical energy for pumping, the use of the thermally actuated hydraulic pumps could prolong the intervals between battery charges, thus making it possible to greatly increase the durations of undersea exploratory missions.

  20. Hall drift and the braking indices of young pulsars

    NASA Astrophysics Data System (ADS)

    Gourgouliatos, K. N.; Cumming, A.

    2015-01-01

    Braking index measurements of young radio pulsars are all smaller than the value expected for spin-down by magnetic dipole braking. We investigate magnetic field evolution in the neutron star crust due to Hall drift as an explanation for observed braking indices. Using numerical simulations and a semi-analytic model, we show that an ?1014 G quadrupolar toroidal field in the neutron star crust at birth leads to growth of the dipole moment at a rate large enough to agree with measured braking indices. A key factor is the density at which the crust yields to magnetic stresses that build up during the evolution, which sets a characteristic minimum Hall time-scale. The observed braking indices of pulsars with inferred dipole fields of ? 1013 G can be explained in this picture, although with a significant octupole component needed in some cases. For the stronger field pulsars, those with Bd ? 1013 G, we find that the magnetic stresses in the crust exceed the maximum shear stress before the pulsar reaches its current age, likely quenching the Hall effect. This may have implications for the magnetar activity seen in the high magnetic field radio pulsar PSR J1846-0258. Observations of braking indices may therefore be a new piece of evidence that neutron stars contain subsurface toroidal fields that are significantly stronger than the dipole field, and may indicate that the Hall effect is important in a wider range of neutron stars than previously thought.

  1. Hard Braking Events Among Novice Teenage Drivers By Passenger Characteristics

    PubMed Central

    Simons-Morton, Bruce G.; Ouimet, Marie Claude; Wang, Jing; Klauer, Sheila G.; Lee, Suzanne E.; Dingus, Thomas A.

    2010-01-01

    Summary In a naturalistic study of teenage drivers (N = 42) hard braking events of ??0.45 g were assessed over the first 6 months of licensure. A total of 1,721 hard braking events were recorded. The video footage of a sample (816) of these events was examined to evaluate validity and reasons for hard braking. Of these, 788 (96.6%) were estimated valid, of which 79.1% were due to driver misjudgment, 10.8% to risky driving behavior, 5.3% to legitimate evasive maneuvers, and 4.8% to distraction. Hard braking events per 10 trips and per 100 miles were compared across passenger characteristics. Hard braking rates per 10 trips among newly licensed teenagers during the first 6 months of licensure were significantly higher when driving with teen passengers and lower with adult passengers than driving alone; rates per 100 miles were lower with adult passengers than with no passengers. Further examination of the results indicates that rates of hard braking with teenage passengers were significantly higher compared with no passengers: 1) for male drivers; 2) during the first month of licensure. The data suggest that that novice teenage driving performance may not be as good or safe when driving alone or with teenage passengers than with adult passengers and provide support for the hypothesis that teenage passengers increase driving risks, particularly during the first month of licensure. PMID:21243109

  2. Development of aircraft brake materials. [evaluation of metal and ceramic materials in sliding tests simulation of aircraft braking

    NASA Technical Reports Server (NTRS)

    Ho, T. L.; Peterson, M. B.

    1974-01-01

    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. Nickel, molybdenum tungsten, Zr02, high temperature cements and carbons were tested. Additives were then incorporated into these materials to optimize their wear or strength behavior with particular emphasis on nickel and molybdenum base materials and a high temperature potassium silicate cement. Optimum materials were developed which improved wear behavior over conventional brake materials in the simulated test. The best materials are a nickel, aluminum oxide, lead tungstate composition containing graphite or molybdenum disulphite; a molybdenum base material containing LPA100 (an intermetallic compound of cobalt, molybdenum, and silicon); and a carbon material (P5).

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

    NASA Astrophysics Data System (ADS)

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

    2013-08-01

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

  4. Downhole hydraulic seismic generator

    Microsoft Academic Search

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

    1990-01-01

    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

  5. Downhole hydraulic seismic generator

    Microsoft Academic Search

    Danny L. Gregory; Harry C. Hardee; David O. Smallwood

    1992-01-01

    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

  6. Downhole hydraulic seismic generator

    DOEpatents

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

    1992-01-01

    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.

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

    SciTech Connect

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

    1995-11-01

    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.

  8. Intelligently Controllable Walker with Magnetorheological Fluid Brake

    NASA Astrophysics Data System (ADS)

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

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

  9. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...or dissipating kinetic energy, and which uses the...returning electrical energy to the propulsion batteries...dissipating electrical energy. Skid number means...that is greater than zero. Spike stop means...by a vehicle from the point of application of...

  10. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...or dissipating kinetic energy, and which uses the...returning electrical energy to the propulsion batteries...dissipating electrical energy. Skid number means...that is greater than zero. Spike stop means...by a vehicle from the point of application of...

  11. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...or dissipating kinetic energy, and which uses the...returning electrical energy to the propulsion batteries...dissipating electrical energy. Skid number means...that is greater than zero. Spike stop means...by a vehicle from the point of application of...

  12. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...or dissipating kinetic energy, and which uses the...returning electrical energy to the propulsion batteries...dissipating electrical energy. Skid number ...that is greater than zero. Spike stop means...by a vehicle from the point of application of...

  13. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...or dissipating kinetic energy, and which uses the...returning electrical energy to the propulsion batteries...dissipating electrical energy. Skid number ...that is greater than zero. Spike stop means...by a vehicle from the point of application of...

  14. Experimental analysis of brake squeal noise on a laboratory brake setup

    NASA Astrophysics Data System (ADS)

    Giannini, Oliviero; Akay, Adnan; Massi, Francesco

    2006-04-01

    The present paper is the first of two papers dealing with brake squeal instability. An experimental setup is specifically designed for this purpose and is characterized by a simple design to aid measurements and modeling. This first paper describes the experimental setup called "laboratory brake" and presents the measurements performed on it to characterize its dynamical behavior and its squeal behavior. The tests are aimed at identifying the key parameters controlling the squeal phenomenon that are necessary to build a model of the setup. The experimental analysis on squeal presented here identifies several characteristics that lead to instabilities and correlates them with the operating parameters as well as with the dynamic behavior of the system. Measurements also highlight that the pad dynamics have a key role in the selection of the squealing modes at one of the out-of-plane eigenfrequency of the system. Finally, the experimental results provide a better understanding of the physics of the squeal mechanism and suggest guidelines to build a representative model of the setup.

  15. Thermophysical Properties of Automotive Metallic Brake Disk Materials

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

    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.

  16. Prosthetic leg powered by MR brake and SMA wires

    NASA Astrophysics Data System (ADS)

    Nguyen, The; Munguia, Vicente; Calderon, Jose

    2014-04-01

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

  17. The contribution of stereo vision to the control of braking.

    PubMed

    Tijtgat, Pieter; Mazyn, Liesbeth; De Laey, Christophe; Lenoir, Matthieu

    2008-03-01

    In this study the contribution of stereo vision to the control of braking in front of a stationary target vehicle was investigated. Participants with normal (StereoN) and weak (StereoW) stereo vision drove a go-cart along a linear track towards a stationary vehicle. They could start braking from a distance of 4, 7, or 10m from the vehicle. Deceleration patterns were measured by means of a laser. A lack of stereo vision was associated with an earlier onset of braking, but the duration of the braking manoeuvre was similar. During the deceleration, the time of peak deceleration occurred earlier in drivers with weak stereo vision. Stopping distance was greater in those lacking in stereo vision. A lack of stereo vision was associated with a more prudent brake behaviour, in which the driver took into account a larger safety margin. This compensation might be caused either by an unconscious adaptation of the human perceptuo-motor system, or by a systematic underestimation of distance remaining due to the lack of stereo vision. In general, a lack of stereo vision did not seem to increase the risk of rear-end collisions. PMID:18329426

  18. Constant-Pressure Hydraulic Pump

    NASA Technical Reports Server (NTRS)

    Galloway, C. W.

    1982-01-01

    Constant output pressure in gas-driven hydraulic pump would be assured in new design for gas-to-hydraulic power converter. With a force-multiplying ring attached to gas piston, expanding gas would apply constant force on hydraulic piston even though gas pressure drops. As a result, pressure of hydraulic fluid remains steady, and power output of the pump does not vary.

  19. 49 CFR 238.15 - Movement of passenger equipment with power brake defects.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Movement of passenger equipment with power brake defects. 238...DEPARTMENT OF TRANSPORTATION PASSENGER EQUIPMENT SAFETY STANDARDS General § 238.15 Movement of passenger equipment with power brake defects....

  20. 49 CFR 238.15 - Movement of passenger equipment with power brake defects.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Movement of passenger equipment with power brake defects. 238...DEPARTMENT OF TRANSPORTATION PASSENGER EQUIPMENT SAFETY STANDARDS General § 238.15 Movement of passenger equipment with power brake defects....

  1. 49 CFR 238.15 - Movement of passenger equipment with power brake defects.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Movement of passenger equipment with power brake defects. 238...DEPARTMENT OF TRANSPORTATION PASSENGER EQUIPMENT SAFETY STANDARDS General § 238.15 Movement of passenger equipment with power brake defects....

  2. Evaluation of driver braking performance to an unexpected object in the roadway 

    E-print Network

    Picha, Dale Louis

    1994-01-01

    components, specifically whether the equation accurately reflects driver and vehicle behaviors during a braking maneuver. This research evaluated the two components of the SSD equation. Four field studies were conducted that evaluated driver braking...

  3. 49 CFR 236.506 - Release of brakes after automatic application.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 false Release of brakes after automatic application...OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES...Train Control and Cab Signal Systems Standards § 236.506 Release of brakes after automatic...

  4. 49 CFR 236.506 - Release of brakes after automatic application.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 false Release of brakes after automatic application...OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES...Train Control and Cab Signal Systems Standards § 236.506 Release of brakes after automatic...

  5. 49 CFR 236.506 - Release of brakes after automatic application.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 false Release of brakes after automatic application...OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES...Train Control and Cab Signal Systems Standards § 236.506 Release of brakes after automatic...

  6. Evaluation of driver braking performance to an unexpected object in the roadway

    E-print Network

    Picha, Dale Louis

    1994-01-01

    components, specifically whether the equation accurately reflects driver and vehicle behaviors during a braking maneuver. This research evaluated the two components of the SSD equation. Four field studies were conducted that evaluated driver braking...

  7. 77 FR 51649 - Federal Motor Vehicle Safety Standards; Motorcycle Brake Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-24

    ...and to assess civil penalties for...simulations, engineering analyses, or...simulations, engineering analyses, or...history in brake system compliance tests...will need re-engineering of their brake systems and that...

  8. Arsenic species and leachability in the fronds of the hyperaccumulator Chinese brake (Pteris vittata L.)

    E-print Network

    Ma, Lena

    Arsenic species and leachability in the fronds of the hyperaccumulator Chinese brake (Pteris June 2002; accepted 9 December 2002 ``Capsule'': Arsenic was predominantly present as inorganic arsenite in the fronds of the hyperaccumulator Chinese brake. Abstract Arsenic speciation is important

  9. Modeling the pneumatic relay valve of an s-cam air brake

    E-print Network

    Vilayannur Natarajan, Shankar

    2005-08-29

    solutions. Moreover the input is a low frequency brake application and hence the numerical noise can be expected to get damped. Hence it is reasonable to expect fairly accurate results for these brake applications. This is corroborated by the fact...

  10. Tribology of hydraulic pumps

    SciTech Connect

    Yamaguchi, A. [Yokohama National Univ. (Japan). Dept. of Mechanical Engineering and Materials Science

    1997-12-31

    To obtain much higher performance than that of alternative power transmission systems, hydraulic systems have been continuously evolving to use high-pressure. Adoption of positive displacement pumps and motors is based on this reason. Therefore, tribology is a key terminology for hydraulic pumps and motors to obtain excellent performance and durability. In this paper the following topics are investigated: (1) the special feature of tribology of hydraulic pumps and motors; (2) indication of the important bearing/sealing parts in piston pumps and effects of the frictional force and leakage flow to performance; (3) the methods to break through the tribological limitation of hydraulic equipment; and (4) optimum design of the bearing/sealing parts used in the fluid to mixed lubrication regions.

  11. Suspensions in hydraulic fracturing

    SciTech Connect

    Shah, S.N. [Univ. of Oklahoma, Norman, OK (United States)

    1996-12-31

    Suspensions or slurries are widely used in well stimulation and hydraulic fracturing processes to enhance the production of oil and gas from the underground hydrocarbon-bearing formation. The success of these processes depends significantly upon having a thorough understanding of the behavior of suspensions used. Therefore, the characterization of suspensions under realistic conditions, for their rheological and hydraulic properties, is very important. This chapter deals with the state-of-the-art hydraulic fracturing suspension technology. Specifically it deals with various types of suspensions used in well stimulation and fracturing processes, their rheological characterization and hydraulic properties, behavior of suspensions in horizontal wells, review of proppant settling velocity and proppant transport in the fracture, and presently available measurement techniques for suspensions and their merits. Future industry needs for better understanding of the complex behavior of suspensions are also addressed. 74 refs., 21 figs., 1 tab.

  12. Hydraulic Fracturing Sand

    USGS Multimedia Gallery

    Fine-grained silica sand is mixed with chemicals and water before being pumped into rock formations to prevent the newly created artificial fractures from closing after hydraulic fracturing is completed....

  13. Stable hydraulic pressure regulator

    NASA Technical Reports Server (NTRS)

    Gold, H.

    1979-01-01

    Neither sensing line restrictors nor frictional dampers are required for stability. Analysis presents method by which stability margin, response, and droop magnitude can be incorporated during design of direct-acting hydraulic pressure regulators.

  14. Angling hydraulic jumps

    NASA Astrophysics Data System (ADS)

    Belmonte, Andrew; Thiffeault, Jean-Luc

    2008-11-01

    We present an experimental and mathematical study of the normal impact of a jet onto an inclined solid surface, focusing on the characteristics of the hydraulic jump. The angle of the surface is varied between vertical and horizontal positions, using both flat and curved (patterned) surfaces. Comparisons of the outer envelope of the hydraulic jump are made with the ballistic theory and the model of Edwards, Howison, Ockendon, & Ockendon.

  15. Portable Hydraulic Powerpack

    NASA Technical Reports Server (NTRS)

    Anderson, L. A.; Henry, R. L.; Fedor, O. H.; Owens, L. J.

    1986-01-01

    Rechargeable hydraulic powerpack functions as lightweight, compact source of mechanical energy. Self-contained hydraulic powerpack derives energy from solid chemical charge. Combustion of charge initiated by small hammer, and revolving feeder replaces charges expended. Combustion gases cool during expansion in turbine and not too hot for release to atmosphere. Unit has applications driving wheelchairs and operating drills, winches, and other equipment in remote areas. Also replaces electric motors and internal-combustion engines as source of power in explosive atmospheres.

  16. Characterization of the high-frequency squeal on a laboratory brake setup

    Microsoft Academic Search

    Oliviero Giannini; Francesco Massi

    2008-01-01

    This paper presents an experimental investigation on high-frequency brake squeal noise conducted on an appropriately designed experimental rig, called laboratory brake.Brake squeal is one of the major issues in the design process of an automotive brake and the development of a robust procedure for a “squeal-free” design is still under investigation. The high-frequency squeal is the most frequent noise generated

  17. Development of a semi-empirical program for predicting the braking performance of a passenger vehicle

    Microsoft Academic Search

    C.-H. Lee; J.-M. Lee; M.-S. Choi; C.-K. Kim; E.-B. Koh

    2011-01-01

    Since the invention of automobiles, the need to know the braking performance of vehicles has been acknowledged. However, because\\u000a there are numerous design variables as well as nonlinearities in the braking system, it is difficult to predict the performance\\u000a accurately. In this paper, a computational program is developed to estimate the braking performance numerically. This synthetic\\u000a braking performance program accounts

  18. Study of Anti-lock Brake System Control Strategy in Automobile

    Microsoft Academic Search

    Jifei Chen; Gangping Tan

    \\u000a Anti-lock Brake System (ABS), which is the advanced system of brake, was developed to base on the adhesion characteristic\\u000a between the tire and the road in automobile. ABS can automatic amend wheel press to prevent wheel from locking at braking\\u000a and can improve braking efficiency. In this paper, the control strategy was present by analyzing principle of ABS and establishing

  19. Regenerative braking device with rotationally mounted energy storage means

    DOEpatents

    Hoppie, Lyle O. (Birmingham, MI)

    1982-03-16

    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.

  20. Double pulsed holography used to investigate noisy brakes

    NASA Astrophysics Data System (ADS)

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

    1996-12-01

    The vibrational characteristics of a noisy passenger car disc brake have been studied using the double pulsed holographic technique which has been developed to allow three orthogonal visual images of a vibrating brake system to be recorded simultaneously. These images show the disc to be vibrating in a bending mode whereas the pad is seen to be excited in a variety of modes such as bending, torsion, and often a combination of both. The development of the technique includes alternative ways of triggering the laser and typical results from the application of these differing methods are also included along with mechanical signals which confirm the visual interpretations. Final results, using a laser trigger delay technique, show that the disc mode waveform rotates about the disc at a rate equivalent to the frequency of vibration divided by the diametral mode order. Early work on a passenger car drum brake is also introduced, this complementing commercial 'noise fix' solutions and a proposed theoretical model.

  1. Evaluation of Corrosion Failure in Tractor-Trailer Brake System

    SciTech Connect

    Wilson, DF

    2002-10-22

    As reported to ORNL, concomitant with the introduction of different deicing and anti-icing compounds, there was an increase in the brake failure rate of tractor-trailer trucks. A forensic evaluation of a failed brake system was performed. Optical and scanning electron microscopic evaluation showed corrosion to be mostly confined to the brake table/lining interface. The corrosion is non-uniform as is to be expected for plain carbon steel in chloride environments. This initial analysis found no evidence for the chlorides of calcium and magnesium, which are the newly introduced deicing and antiicing compounds and are less soluble in water than the identified chlorides of sodium and potassium, in the scale. The result could be as a result of non-exposure of the examined brake table to calcium and magnesium chloride. The mechanisms for the increased failure rate are postulated as being an increased rate of corrosion due to positive shifts in the corrosion potential, and an increased amount of corrosion due to an increased ''time of wetness'' that results from the presence of hygroscopic salts. Laboratory scale evaluation of the corrosion of plain carbon steel in simulated deicing and anti-icing solutions need to be performed to determine corrosion rates and morphological development of corrosion product, to compare laboratory data to in-service data, and to rank economically feasible replacement materials for low carbon steel. In addition, the mechanical behavior of the lining attached to the brake shoe table needs to be assessed. It is opined that an appropriate adjustment of materials could easily allow for a doubling of a brake table/lining lifetime. Suggestions for additional work, to clarify the mechanisms of rust jacking and to develop possible solutions, are described.

  2. Analysis of brake squeal noise using the finite element method: A parametric study

    Microsoft Academic Search

    Mário Trichês Júnior; Samir N. Y. Gerges; Roberto Jordan

    2008-01-01

    Brake squeal noise has been under investigation by automotive manufacturers for decades due to consistent customer complaints and high warranty costs. J.D. Power surveys consistently show brake noise as being one of the most critical vehicle quality measurements. Furthermore, the development of methods to predict noise occurrence during the design of a brake system has been the target of many

  3. 49 CFR 238.17 - Movement of passenger equipment with other than power brake defects.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...equipment with other than power brake defects. Beginning...equipment with other than a power brake defect. (Passenger cars...this part, other than a power brake defect, may be moved only... (ii) It makes any unusual noise when its wheel set is spun...

  4. Instabilities in the sliding of continua with surface inertias: An initiation mechanism for brake noise

    Microsoft Academic Search

    M. Graf; G.-P. Ostermeyer

    2011-01-01

    This paper presents a model for friction-induced vibration in brake systems, which takes a homogeneous tribological layer on the brake pad into account. The derived model consists of two flat elastic bodies sliding against each other with a constant coefficient of friction. In brake tribology, like in most tribological processes, a surface structure is observed, which can be modeled as

  5. 49 CFR 238.17 - Movement of passenger equipment with other than power brake defects.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...equipment with other than power brake defects. Beginning...equipment with other than a power brake defect. (Passenger cars...this part, other than a power brake defect, may be moved only... (ii) It makes any unusual noise when its wheel set is spun...

  6. 49 CFR 238.17 - Movement of passenger equipment with other than power brake defects.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...equipment with other than power brake defects. Beginning...equipment with other than a power brake defect. (Passenger cars...this part, other than a power brake defect, may be moved only... (ii) It makes any unusual noise when its wheel set is spun...

  7. Auto Mechanics I. Learning Activity Packets (LAPs). Section E--Brakes.

    ERIC Educational Resources Information Center

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

    This document contains two learning activity packets (LAPs) that outline the study activities for the "brakes" instructional area for an Auto Mechanics I course. The two LAPs cover the following topics: brake systems and power disc brakes. Each LAP contains a cover sheet that describes its purpose, an introduction, and the tasks included in the…

  8. The effect of temperature rise of the fuzzy logic-controlled braking resistors on transient stability

    Microsoft Academic Search

    M. H. Ali; T. Murata; J. Tamura

    2004-01-01

    Braking resistor is a very powerful tool to improve transient stability in a power system. Usually, a fixed value of the braking resistor is considered for the transient stability analysis. However, when the braking resistor is in operation, temperature of the resistor material rises above ambient temperature which ultimately causes the resistance value to increase. This paper analyzes the effect

  9. 49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

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

    ERIC Educational Resources Information Center

    Hockicko, Peter; Trpišová, Beáta; Ondruš, Ján

    2014-01-01

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

  11. 49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

  12. 49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

  13. 49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

  14. 49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

  15. 49 CFR 232.207 - Class IA brake tests-1,000-mile inspection.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Class IA brake tests-1,000-mile inspection...Testing Requirements § 232.207 Class IA brake tests—1,000-mile inspection...213, each train shall receive a Class IA brake test performed by a qualified...

  16. 49 CFR 232.207 - Class IA brake tests-1,000-mile inspection.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Class IA brake tests-1,000-mile inspection...Testing Requirements § 232.207 Class IA brake tests—1,000-mile inspection...213, each train shall receive a Class IA brake test performed by a qualified...

  17. Study of the nonlinear stationary dynamic of single and multi instabilities for disc brake squeal

    E-print Network

    Boyer, Edmond

    finite element model of brake system including the disc and the pad. The nonlinear dynamical behaviors under study represents a simplified brake. It is composed by a pad and a disc that are the mainStudy of the nonlinear stationary dynamic of single and multi instabilities for disc brake squeal

  18. Control Engineering Practice 11 (2003) 163170 A mechatronic conception of a new intelligent braking system

    E-print Network

    Paris-Sud XI, Université de

    2003-01-01

    disc brake'' principle, which means that the classic pads are replaced by the whole discs and that braking system G.L. Gissingera, *, C. Menardb , A. Constansb a Laboratoire MIAM/ESSAIM, University describes a new intelligent braking system for motor vehicles. A mechatronic approach helped to avoid some

  19. Motion capture of a pad measured with accelerometers during squeal noise in a real brake system

    E-print Network

    Paris-Sud XI, Université de

    Motion capture of a pad measured with accelerometers during squeal noise in a real brake system Brakes - 126 Rue de Stalingrad - 93700 DRANCY - FRANCE Abstract The operating deflection shape of a pad composed of beams on which brake pads were fixed. They measured the operational deflections with a laser

  20. 49 CFR 571.122 - Standard No. 122; Motorcycle brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...order to supply and regulate the energy required for braking the motorcycle...a brake system in which the energy necessary to produce the braking...rider assisted by one or more energy supplying devices, for example...traveled by the motorcycle from the point the rider begins to...

  1. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Modification of the single car air brake test procedures. 232...Requirements § 232.307 Modification of the single car air brake test procedures. (a...railroad industry may seek modification of the single car air brake test procedures...

  2. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Modification of the single car air brake test procedures. 232...Requirements § 232.307 Modification of the single car air brake test procedures. (a...railroad industry may seek modification of the single car air brake test procedures...

  3. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Modification of the single car air brake test procedures. 232...Requirements § 232.307 Modification of the single car air brake test procedures. (a...railroad industry may seek modification of the single car air brake test procedures...

  4. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Modification of the single car air brake test procedures. 232...Requirements § 232.307 Modification of the single car air brake test procedures. (a...railroad industry may seek modification of the single car air brake test procedures...

  5. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Modification of the single car air brake test procedures. 232...Requirements § 232.307 Modification of the single car air brake test procedures. (a...railroad industry may seek modification of the single car air brake test procedures...

  6. Thiol synthesis and arsenic hyperaccumulation in Pteris vittata (Chinese brake fern)

    E-print Network

    Ma, Lena

    Thiol synthesis and arsenic hyperaccumulation in Pteris vittata (Chinese brake fern) Weihua Zhanga in arsenic detoxification. Abstract Pteris vittata (Chinese brake fern) has potential for phytoremediation to be a supplement. Ó 2004 Elsevier Ltd. All rights reserved. Keywords: Pteris vittata; Chinese brake fern; Thiols

  7. 49 CFR 571.116 - Standard No. 116; Motor vehicle brake fluids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...sedimentation of the water-wet brake fluid shall...f) The pH value of water-wet brake fluid...sloughing; (h) The hardness of the cup shall not...5 parts of distilled water to 95 parts of ethanol. S7.4Measuring the hardness of SBR brake cups....

  8. An active control method to reduce the effect of negative damping in disk brake system

    Microsoft Academic Search

    Sayed-Mahdi Hashemi-Dehkordi; Musa Mailah; A. R. A. Bakar

    2009-01-01

    In this paper, a novel approach to reduce the effect of negative damping that causes brake noise is proposed by applying an active force control (AFC) based strategy to a two degree-of-freedom model of a disk brake system. At first, the disc brake model is simulated and analyzed using a closed loop pure PID controller. Later, it is integrated with

  9. Dual Mode Vehicle with In-Wheel Motor: Regenerative Braking Optimization

    E-print Network

    Paris-Sud XI, Université de

    Dual Mode Vehicle with In-Wheel Motor: Regenerative Braking Optimization G. Le Solliec1*, A. Chasse: Regenerative Braking Optimization -- To meet the growing need for mobility of people and goods while massively the benefit of such an architecture to optimize the regenerative braking while ensuring a safe dynamic

  10. Analysis of compressed air regenerative braking and a thermally enhanced option

    Microsoft Academic Search

    F. Wicks; J. Maleszweski; C. Wright; J. Zarybnicky

    2002-01-01

    Obtaining a net benefit from regenerative braking is difficult. Various forms of regenerative braking systems have been proposed. They include electric batteries, capacitors, flywheels, and compressed air. Some have been implemented on a limited scale. The benefits of regenerative braking systems are easy to qualitatively describe, but can be challenging to quantify. The potential benefits depend upon obvious things such

  11. Regenerative braking algorithm for a parallel hybrid electric vehicle with continuously variable transmission

    Microsoft Academic Search

    Wang Feng; Zhong Hu; Mao Xiao-jian; Yang Lin; Zhuo Bin

    2007-01-01

    A novel regenerative braking algorithm based on continuously variable transmission is proposed to make effective and maximum use of the brake energy in order to improve fuel economy. In the braking torque distribution of the novel regenerative algorithm, the regenerative torque is determined by considering the vehicle velocity, the maximal generation torque and state of the electric motor, the maximal

  12. Power Management Strategy with Regenerative Braking For Fuel Cell Hybrid Electric Vehicle

    Microsoft Academic Search

    Yu Shuang; Zhang Junzhi; Wang Lifang

    2009-01-01

    A novel power management strategy based on regenerative braking is proposed to make optimal power distribution between fuel cell system and batteries in order to improve the utility of braking energy and decrease the power loss for fuel cell electric vehicle. With the integrated regenerative braking strategy, the novel control algorithm takes the charging power loss from regenerated energy into

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

    Microsoft Academic Search

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

    2003-01-01

    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.

  14. Reduction of squeal noise from disc brake systems using constrained layer damping

    Microsoft Academic Search

    M. Triches Jr; S. N. Y. Gerges; R. Jordan

    2004-01-01

    Squeal noise generation during braking is a complic ated dynamic problem which automobile manufacturers have confronted for decade s. Customer complaints result in significant yearly warranty costs. More importantly , customer dissatisfaction may result in rejection of certain brands of brake systems. In or der to produce quality automobiles that can compete in today's marketplace, the occurrence of disc brake

  15. Reliability prediction and Markov analysis of braking system based on Relex 2009

    Microsoft Academic Search

    Ling-yi Li; Deng-jiang Wang; Tao-tao Zhou; Ting Tang; Hai Sun

    2011-01-01

    To analyze the reliability of automobile braking system, the reliability module and Markov module of Relex studio 2009 are adopted in this paper. Firstly, braking system is analyzed systematically, including function, braking process, components. Then Competitive failure models are identified and reliability model is established. Failure rate of each subsystem is obtained using the reliability prediction. According to the reliability

  16. Molecular brake pad hypothesis: pulling off the brakes for emotional memory.

    PubMed

    Vogel-Ciernia, Annie; Wood, Marcelo A

    2012-01-01

    Under basal conditions histone deacetylases(HDACs) and their associated co-repressor complexes serve as molecular 'brake pads' to prevent the gene expression required for long-term memory formation. Following a learning event, HDACs and their co-repressor complexes are removed from a subset of specific gene promoters, allowing the histone acetylation and active gene expression required for long-term memory formation.Inhibition of HDACs increases histone acetylation,extends gene expression profiles, and allows for the formation of persistent long-term memories for training events that are otherwise forgotten. We propose that emotionally salient experiences have utilized this system to form strong and persistent memories for behaviorally significant events. Consequently, the presence or absence of HDACs at a selection of specific gene promoters could serve as a critical barrier for permitting the formation of long-term memories. PMID:23096102

  17. Effects of hard particles on friction coefficients and particle embedment in brake system during hard braking

    NASA Astrophysics Data System (ADS)

    Abdul Hamid, M. K.; Stachowiak, G. W.; Syahrullail, S.

    2012-06-01

    The effects of hard particles on the friction coefficients and particle embedment during hard braking were investigated. Silica sands grit of the size between 180 to 355 ?m were used during the experiments. The results were compared to the results obtained without the grit particles present in order to determine the change in friction coefficient, the fluctuation of frictional oscillation amplitude, and the percentage of particle embedment. Different sliding speeds were applied to investigate the relationship between particle embedment with friction coefficient and friction oscillation amplitude. Presence of hard particles of different grit size is found to significantly affect the friction coefficient and standard deviation of friction oscillation amplitude values. The friction coefficient and standard deviation values of friction oscillation amplitude increase with particle embedment due to the rapid changes of the effective contact area and the abrasion mode operating in the gap interface. Also, particle embedment tends to increase the disc surface roughness and influence the stopping time of the disc.

  18. Disc brake squeal characterization through simplified test rigs

    NASA Astrophysics Data System (ADS)

    Akay, A.; Giannini, O.; Massi, F.; Sestieri, A.

    2009-11-01

    This paper presents a review of recent investigations on brake squeal noise carried out on simplified experimental rigs. The common theme of these works is that of approaching the study of squeal noise on experimental set-ups that are much simpler than commercial disc brakes, providing the possibility of repeatable measurements of squeal occurrence. As a consequence, it is possible to build consistent and robust models of the experimental apparatus to simulate the squeal events and to understand the physics behind squeal instabilities.

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

    NASA Astrophysics Data System (ADS)

    Belhocine, Ali; Bouchetara, Mostefa

    2013-08-01

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

  20. Transient analysis of thermoelastic contact problem of disk brakes

    NASA Astrophysics Data System (ADS)

    Belhocine, Ali; Bouchetara, Mostefa

    2013-06-01

    The main purpose of this study is to analyze the thermomechanical behavior of the dry contact between the brake disk and pads during the braking phase. The simulation strategy is based on computer code ANSYS11. The modeling of transient temperature in the disk is actually used to identify the factor of geometric design of the disk to install the ventilation system in vehicles. The thermal-structural analysis is then used with coupling to determine the deformation 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.

  1. Aluminum runway surface as possible aid to aircraft braking

    NASA Technical Reports Server (NTRS)

    Miller, C. D.; Pinkel, I. I.

    1973-01-01

    Several concepts are described for use singly or in combination to improve aircraft braking. All involve a thin layer of aluminum covering all or part of the runway. Advantage would derive from faster heat conduction from the tire-runway interface. Heating of tread surface with consequent softening and loss of friction coefficient should be reduced. Equations are developed indicating that at least 99 percent of friction heat should flow into the aluminum. Preliminary test results indicate a coefficient of sliding friction of 1.4, with predictably slight heating of tread. Elimination of conventional brakes is at least a remote possibility.

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

    NASA Astrophysics Data System (ADS)

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

    2005-05-01

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

  3. Analytica Chimica Acta 504 (2004) 199207 Arsenic speciation in Chinese brake fern by ion-pair high-performance

    E-print Network

    Ma, Lena

    2004-01-01

    Analytica Chimica Acta 504 (2004) 199­207 Arsenic speciation in Chinese brake fern by ion-pair high) and arsenate [As(V)] in Chinese brake fern (Pteris vittata L.). The separation was performed on a reverse in the Chinese brake fern, indicating that Chinese brake fern can convert MMA to DMA by methylation. © 2003

  4. 486 IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 54, NO. 2, MARCH 2005 Iterative Learning Control of Antilock Braking of

    E-print Network

    Mi, Chunting "Chris"

    learning control, regener- ative braking, road vehicle control, road vehicle electric propul- sion, road of regenerative braking [19], and motor control [20]. Antilock braking and traction control of pure electric Control of Antilock Braking of Electric and Hybrid Vehicles Chunting Mi, Senior Member, IEEE, Hui Lin

  5. Cracking diagnostics of brake pedals during press forming operations

    Microsoft Academic Search

    J Setién; J. J González; J. A Polanco

    2000-01-01

    In this work a study of the cracking problems arising in manufacturing of steel brake pedals by press forming is presented. Cracks were detected in critical zones of the part revealing a possible lack of ductility in the constitutive material. In order to overcome this problem, a detailed study of the behaviour of the steel used has been carried out.

  6. Three Dimensional Animation of a Disc Brake System Generating Noise

    Microsoft Academic Search

    Chris Talbot; Kamal-al Banawi; John D Fieldhouse

    Brake noise investigations using the whole body visual technique of double pulsed holographic interferometry have been extended so that a series of time related interferograms may be recorded over a cycle of excitation. The main disadvantage of such a technique is that the extraction of the valuable information contained within the holograms requires a degree of expertise in the interpretation

  7. Development of Diagnostic Algorithms for Air Brakes in Trucks 

    E-print Network

    Dhar, Sandeep

    2011-10-21

    -state pushrod stroke has been developed. The scheme is expected to expedite the inspection process for the out-of-adjustment of pushrod. Experimental data from the air brake test setup at Texas A and M University has been used for corroborating both the models...

  8. 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

  9. 49 CFR 238.317 - Class II brake test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...test shall be performed prior to the train's departure from the terminal complex with passengers; (2) Prior to the first morning departure of each commuter or short-distance intercity passenger train where a Class I brake test remains valid as...

  10. 49 CFR 238.317 - Class II brake test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...test shall be performed prior to the train's departure from the terminal complex with passengers; (2) Prior to the first morning departure of each commuter or short-distance intercity passenger train where a Class I brake test remains valid as...

  11. An improved automotive brake lining using fibrous potassium titanate

    NASA Technical Reports Server (NTRS)

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

    1976-01-01

    Simultaneous fade reduction and wear improvement of a commercial automotive brake lining were achieved by adding fibrous potassium titanate. The dependence of friction and wear characteristics on quantitative variations in potassium titanate, asbestos, phenolic binder, and organic and inorganic modifiers was evaluated.

  12. HYDRO BRAKE REGULATED STORAGE SYSTEM FOR STORMWATER MANAGEMENT

    EPA Science Inventory

    This research project was initiated with the overall objective of determining the ability of the Hydro Brake flow control device, in conjunction with off-line underground storage, to limit the rate of stormwater flow into combined sewers. The intended result of this control was t...

  13. Pulsar motion effect and Geminga's high braking index

    NASA Astrophysics Data System (ADS)

    Bisnovatyi-Kogan, G. S.; Postnov, K. A.

    1993-12-01

    THE pulsar braking index, n, is a dimensionless quantity describing the rate at which a magnetized neutron star loses rotational energy1. It can be determined from pulsar timing measurements, and for distant pulsars is found to lie close to n = 3 (ref. 2), as predicted by theoretical models of pulsar emission mechanisms3-5. In contrast, the timing parameters-in particular the second derivative of the pulsation frequency-of the nearby pulsar Geminga6-11 indicate an extremely large braking index of about 10-30. To understand this property of Geminga, we consider here the effect on the measured timing parameters of a pulsar's motion through space. We find that the Doppler effect alone can give a high apparent braking index, but only if the pulsar is very close and has an abnormally high velocity (>1000kms-1). A more likely (but related) cause of the high braking index is the pulsar's proper motion: failure to correct for changes in the source coordinates with time can greatly influence the higher derivatives of the pulsar frequency, and lead to an erroneous value of n. A self-consistent analysis of the timing data, which account for both the proper motion and the Doppler effect, should permit a reliable estimate of the distance to Geminga.

  14. 6. OBLIQUE VIEW OF HOIST, SHOWING WOODEN BRAKE SHOES, REDUCTION ...

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

    6. OBLIQUE VIEW OF HOIST, SHOWING WOODEN BRAKE SHOES, REDUCTION GEARS AND BED FOR (MISSING) CLUTCH/DRIVE GEAR UNIT, LOOKING NORTHWEST - Buffalo Coal Mine, Vulcan Cable Hoist, Wishbone Hill, Southeast end, near Moose Creek, Sutton, Matanuska-Susitna Borough, AK

  15. HDAC3 and the molecular brake pad hypothesis.

    PubMed

    McQuown, Susan C; Wood, Marcelo A

    2011-07-01

    Successful transcription of specific genes required for long-term memory processes involves the orchestrated effort of not only transcription factors, but also very specific enzymatic protein complexes that modify chromatin structure. Chromatin modification has been identified as a pivotal molecular mechanism underlying certain forms of synaptic plasticity and memory. The best-studied form of chromatin modification in the learning and memory field is histone acetylation, which is regulated by histone acetyltransferases and histone deacetylases (HDACs). HDAC inhibitors have been shown to strongly enhance long-term memory processes, and recent work has aimed to identify contributions of individual HDACs. In this review, we focus on HDAC3 and discuss its recently defined role as a negative regulator of long-term memory formation. HDAC3 is part of a corepressor complex and has direct interactions with Class II HDACs that may be important for its molecular and behavioral consequences. And last, we propose the "molecular brake pad" hypothesis of HDAC function. The HDACs and associated corepressor complexes may function in neurons, in part, as "molecular brake pads." HDACs are localized to promoters of active genes and act as a persistent clamp that requires strong activity-dependent signaling to temporarily release these complexes (or brake pads) to activate gene expression required for long-term memory formation. Thus, HDAC inhibition removes the "molecular brake pads" constraining the processes necessary for long-term memory and results in strong, persistent memory formation. PMID:21521655

  16. Disk brake squeal prediction using the ABLE algorithm

    NASA Astrophysics Data System (ADS)

    Lou, G.; Wu, T. W.; Bai, Z.

    2004-05-01

    Disk brake squeal noise is mainly due to unstable friction-induced vibration. A typical disk brake system includes two pads, a rotor, a caliper and a piston. In order to predict if a disk brake system will generate squeal, the finite element method (FEM) is used to simulate the system. At the contact interfaces between the pads and the rotor, the normal displacement is continuous and Coulomb's friction law is applied. Thus, the resulting FEM matrices of the dynamic system become unsymmetric, which will yield complex eigenvalues. Any complex eigenvalue with a positive real part indicates an unstable mode, which may result in squeal. In real-world applications, the FEM model of a disk brake system usually contains tens of thousands of degrees of freedom (d.o.f.s). Therefore any direct eigenvalue solver based on the dense matrix data structure cannot efficiently perform the analysis, mainly due to its huge memory requirement and long computation time. It is well known that the FEM matrices are generally sparse and hence only the non-zeros of the matrices need to be stored for eigenvalue analysis. A recently developed iterative method named ABLE is used in this paper to search for any unstable modes within a certain user-specified frequency range. The complex eigenvalue solver ABLE is based on an adaptive block Lanczos method for sparse unsymmetric matrices. Numerical examples are presented to demonstrate the formulation and the eigenvalues are compared to the results from the component modal synthesis (CMS).

  17. Very low braking index for the Vela pulsar

    Microsoft Academic Search

    A. G. Lyne; R. S. Pritchard; F. Graham-Smith; F. Camilo

    1996-01-01

    THE rotation rate of a pulsar is thought to decrease with time according to a simple power law, with a 'braking index' equal to 3 if rotational energy is lost through radiation from a dipolar magnetic field1-3. The age of the pulsar can accordingly be determined simply by measuring the current rotation rate, and its current rate of change. Here

  18. 49 CFR 238.309 - Periodic brake equipment maintenance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...following schedule: (1) Every 1,840 days for locomotives equipped with CCB-1, CCB-2, CCB-26, EPIC 1 (formerly EPIC 3102), EPIC 3102D2, EPIC 2, KB-HS1, or Fastbrake brake systems. (2) Every 1,476 days for that portion...

  19. 49 CFR 238.309 - Periodic brake equipment maintenance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...following schedule: (1) Every 1,840 days for locomotives equipped with CCB-1, CCB-2, CCB-26, EPIC 1 (formerly EPIC 3102), EPIC 3102D2, EPIC 2, KB-HS1, or Fastbrake brake systems. (2) Every 1,476 days for that portion...

  20. 49 CFR 238.309 - Periodic brake equipment maintenance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...following schedule: (1) Every 1,840 days for locomotives equipped with CCB-1, CCB-2, CCB-26, EPIC 1 (formerly EPIC 3102), EPIC 3102D2, EPIC 2, KB-HS1, or Fastbrake brake systems. (2) Every 1,476 days for that portion...

  1. Emergency Braking: A Study of Network and Application Performance

    E-print Network

    Lo Cigno, Renato Antonio

    and whose adaptive cruise control implements a correct decelera- tion strategy. Categories and Subject VANET, vehicular networks, emergency braking control, collabo- rative adaptive cruise control, ns-3 correctly the inter- actions of the communications and protocols with the car's adap- tive cruise control

  2. DISC BRAKE SYSTEM (CENTER), INCLUDING BELT DRIVE TO SECONDARY GENERAL ...

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

    DISC BRAKE SYSTEM (CENTER), INCLUDING BELT DRIVE TO SECONDARY GENERAL MOTORS ENGINE (LEFT)AND FERREL REDUCTION GEAR CONNECTION TO ALLIS-CHALMERS DIESEL ENGINE (RIGHT), LOOKING NORTH. NOTE TORQUE CONVERTER (TOP) AND THROTTLE (BELOW) LINES CONNECTING TO PRIMARY ENGINE. - Mad River Glen, Single Chair Ski Lift, 62 Mad River Glen Resort Road, Fayston, Washington County, VT

  3. Magnetic braking and ambipolar diffusion in metal-poor protostars

    Microsoft Academic Search

    Hans Zinnecker

    2009-01-01

    In this short note, we raise the issue how magnetic braking of prestellar and protostellar condensations depends on the metallicity of the molecular gas cloud. We suggest that the degree of ionization, which determines the timescale for redistribution of magnetic flux (ambipolar diffusion) in the dense cloud core, depends linearly on the heavy element and dust abundance of the gas.

  4. Active Pedestrian Safety by Automatic Braking and Evasive Steering

    E-print Network

    Gavrila, Dariu M.

    1 Active Pedestrian Safety by Automatic Braking and Evasive Steering C. Keller, T. Dang, H. Fritz of crashes. This paper presents a novel active pedestrian safety system, which combines sensing, situation-- pedestrian detection, computer vision, active safety ITS, vehicle control I. INTRODUCTION Pedestrians

  5. 53. Drive shaft, motors, eddie currents, brakes, and differential gears ...

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

    53. Drive shaft, motors, eddie currents, brakes, and differential gears in south machinery room (interior of both machinery rooms is identical). Facing east. - Henry Ford Bridge, Spanning Cerritos Channel, Los Angeles-Long Beach Harbor, Los Angeles, Los Angeles County, CA

  6. Intelligent Braking: The Seeing Car Improves Safety on the Road

    Microsoft Academic Search

    R. Adomat; G. Geduld; M. Schamberger; Jürgen Diebold; M. Klug

    Over the past few years, the performance of active safety systems (chassis management, steering, brake control and stability systems) and passive safety systems (seat belts, airbags, headrests and the passenger safety cell) has improved substantially, thanks mainly to electronics. However, since development activities in the two sectors — active and passive safety — have been kept largely separate, significant safety

  7. The stability of motorcycles under acceleration and braking

    Microsoft Academic Search

    D J N Limebeer; R S Sharp; S Evangelou

    2001-01-01

    A comprehensive study of the e Vects of acceleration and braking on motorcycle stability is presented. This work is based on a modi® ed version of a dynamic model presented earlier, and is thought to be the most comprehensive motorcycle dynamic model in the public domain. Extensive use is made of both non-linear and linearized models. The models are written

  8. Nonsmooth dynamics of disc brake systems and aeroelastic panels

    Microsoft Academic Search

    Dumitru Marian Beloiu

    2005-01-01

    Contact forces and boundary conditions relaxation play an important role in the dynamic behaviors of mechanical systems such as disc brake systems, jointed structures, and aeroelastic panels. Contact forces between sliding surfaces are strongly nonlinear, non-smooth, and random; and thus can result in complex dynamic characteristics. In addition, boundary conditions relaxation causes stiffness and damping variations, and thus affects structural

  9. 49 CFR 232.109 - Dynamic brake requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (2) Display in real-time in the cab of the...at the grids on the system; and (2) Display...deceleration rate or in real-time in the cab of the... (j) A railroad operating a train with a brake system that includes...

  10. Neural-network hybrid control for antilock braking systems.

    PubMed

    Lin, Chih-Min; Hsu, C F

    2003-01-01

    The antilock braking systems are designed to maximize wheel traction by preventing the wheels from locking during braking, while also maintaining adequate vehicle steerability; however, the performance is often degraded under harsh road conditions. In this paper, a hybrid control system with a recurrent neural network (RNN) observer is developed for antilock braking systems. This hybrid control system is comprised of an ideal controller and a compensation controller. The ideal controller, containing an RNN uncertainty observer, is the principal controller; and the compensation controller is a compensator for the difference between the system uncertainty and the estimated uncertainty. Since for dynamic response the RNN has capabilities superior to the feedforward NN, it is utilized for the uncertainty observer. The Taylor linearization technique is employed to increase the learning ability of the RNN. In addition, the on-line parameter adaptation laws are derived based on a Lyapunov function, so the stability of the system can be guaranteed. Simulations are performed to demonstrate the effectiveness of the proposed NN hybrid control system for antilock braking control under various road conditions. PMID:18238018

  11. Grey relation analysis on fuzzy fault tree of disk brake

    Microsoft Academic Search

    Dezhong Ma; Yongqing Jang; Zhen Zhou; Tonghui Zhao; Dawei Lin

    2011-01-01

    The fault states are fuzzy and the relationship between the primary and the secondary factor leading to the fault is uncertain in the course of the reliability analysis of disk brake. To solve these problems, the fuzzy grey relation analysis is used to improve the traditional method, Fault Tree Analysis (FTA). The triangle fuzzy number is used to represent the

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

    ERIC Educational Resources Information Center

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

  13. 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

  14. Electric propulsion and braking system for automotive vehicles

    SciTech Connect

    Preikschat, F.K.

    1982-12-14

    An electric propulsion and braking system which includes a plurality of high-speed, dc commutatorless motors each coupled to a wheel of an automotive vehicle through an associated fixedratio mechanical transmission. Each motor includes a field winding, an armature winding, and a commutation circuit for the armature winding. During propulsion, each commutation circuit is enabled and, during braking, each commutation circuit is disabled. Control of the amount of propulsion and braking is afforded by varying the dc source voltage across each commutation circuit and by varying the field current in each field winding. The dc source voltage across each commutation circuit is varied by connecting the commutation circuits and a plurality of main electrical energy sources in selected series, series/parallel, and parallel combinations. The field current in each field winding is varied by connecting the field windings with an auxiliary electrical energy source in selected series, series/parallel and parallel combinations, and by duty-cycling the selected combination. The various series, series/parallel and parallel combinations are selected by, and the duty-cycling of the selected field winding combination is controlled by, a microprocessor receiving signals representing the magnitude of electrical energy transfer between the main electrical energy sources and the motors, the position of an acceleration pedal, the position of a brake pedal, the velocity of the vehicle, the dc source voltage across each commutation circuit, and the armature voltage across each armature winding.

  15. Energy savings through regenerative braking using retrofit converters

    Microsoft Academic Search

    Frank Flinders; Rajan Mathew; Wardina Oghanna

    1995-01-01

    This paper explores the benefits and feasibility of retrofitting existing phase controlled DC motor drives in the Queensland Rail coal transport system with PWM rectifier technology. The major benefits of this would be, the replacement of the dynamic brake with a regenerative system and unity power factor operation with a high quality input current waveshape. Test results indicate that very

  16. 49 CFR 570.5 - Service brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...of 10,000 Pounds or Less § 570.5 Service...distance that the pedal has traveled from its free position...force variance. (2) Road test. The service brake...distance of 25 feet or less from a speed of 20 miles...Inspection procedure. The road test shall be...

  17. 49 CFR 570.5 - Service brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...of 10,000 Pounds or Less § 570.5 Service...distance that the pedal has traveled from its free position...force variance. (2) Road test. The service brake...distance of 25 feet or less from a speed of 20 miles...Inspection procedure. The road test shall be...

  18. 49 CFR 570.5 - Service brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...of 10,000 Pounds or Less § 570.5 Service...distance that the pedal has traveled from its free position...force variance. (2) Road test. The service brake...distance of 25 feet or less from a speed of 20 miles...Inspection procedure. The road test shall be...

  19. 49 CFR 570.5 - Service brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...of 10,000 Pounds or Less § 570.5 Service...distance that the pedal has traveled from its free position...force variance. (2) Road test. The service brake...distance of 25 feet or less from a speed of 20 miles...Inspection procedure. The road test shall be...

  20. Design of antilock braking system based on variable structure control

    Microsoft Academic Search

    Li Junwei; Wang Jian

    2009-01-01

    Antilock braking system (ABS) is an important part to improve the automobile's active safety. In general, ABS is designed to achieve maximum negative acceleration by preventing the wheels from locking. Researches show that the friction between road and tire is a nonlinear function of wheel slip. In this paper, to deal with the strong nonlinearity in the design of ABS

  1. Automobile brake system monitoring device based on EHF autodyne generators

    Microsoft Academic Search

    S. D. Votoropin; V. P. Yurchakov

    2000-01-01

    The results of research and development of the test sample of a radio-wave device for vehicle movement parameters monitoring are summarized in this report. The device has been designed for the quick and precise control of a vehicle brake system in stationary (at car repair stations, automobile factories) as well as in road conditions. The autonomous device consists of a

  2. Geostatistical inference of hydraulic conductivity and dispersivities from hydraulic heads and tracer data

    E-print Network

    Cirpka, Olaf Arie

    Geostatistical inference of hydraulic conductivity and dispersivities from hydraulic heads; accepted 25 April 2006; published 10 August 2006. [1] In groundwater, hydraulic heads and solute arrival times depend primarily on the hydraulic conductivity field and hydraulic boundary conditions. The spread

  3. 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.

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

    NASA Astrophysics Data System (ADS)

    Sarkar, C.; Hirani, H.

    2013-11-01

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

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

    NASA Astrophysics Data System (ADS)

    Hockicko, Peter; Trpišová, Beáta; Ondruš, Ján

    2014-12-01

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

  6. What Is Hydraulic Fracturing?

    NSDL National Science Digital Library

    2012-01-01

    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.

  7. Keeping hydraulic fluid clean

    SciTech Connect

    Downs, D.C. [Vickers, Inc., Maumee, OH (United States)

    1997-03-01

    Overall, fluid power is one of the most reliable and repeatable forms of motion control. However, failures do occur. Recent research has found that the root cause of many hydraulic component and system failures is fluid contamination and inadequate contamination control practices. Preventing unplanned downtime through systemic contamination control and proactive or predictive maintenance is an effective strategy that significantly reduces problems. Understanding the principles involved assist the plant engineer, machine operators, and maintenance personnel in economically achieving maximum hydraulic system life and minimum downtime. The paper discusses the sources of contamination, contamination damage, systematic contamination control, filters, and filter location.

  8. Hydraulics of wells

    USGS Publications Warehouse

    McLaughlin, Thad G.

    1955-01-01

    Although the subject of this lecture is supposed to be concerned primarily with the hydraulics of wells, Professor Weers has asked that I also discuss the effects tat geological formations have on the quantity and quality of water available to wells. I will discuss the geology of Colorado in relation to the availability and quality of water with particular reference to the most productive aquifers or water-bearing formations in the State. I will then discuss the hydraulics of wells with the aim of emphasizing the differences between water-table and artesian conditions.

  9. 46 CFR 28.405 - Hydraulic equipment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...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...

  10. 46 CFR 28.405 - Hydraulic equipment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...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...

  11. 46 CFR 28.405 - Hydraulic equipment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...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...

  12. 46 CFR 28.405 - Hydraulic equipment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...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...

  13. 46 CFR 28.880 - Hydraulic equipment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...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...

  14. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    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.

  16. Investigation of temperature and thermal stress in ventilated disc brake based on 3D thermo-mechanical coupling model

    Microsoft Academic Search

    Pyung Hwang; Xuan Wu

    2010-01-01

    Ventilated disc brakes are widely used for reducing velocity due to their braking stability, controllability and ability to\\u000a prove a wide-ranging brake torque. During braking, the kinetic energy and potential energies of a moving vehicle are converted\\u000a into thermal energy through friction heating between the brake disc and the pads. The object of the present study is to investigate\\u000a the

  17. Cradle modification for hydraulic ram

    SciTech Connect

    Koons, B.M.

    1995-03-02

    The analysis of the cradle hydraulic system considers stress, weld strength, and hydraulic forces required to lift and support the cradle/pump assembly. The stress and weld strength of the cradle modifications is evaluated to ensure that they meet the requirements of the American Institute for Steel Construction (AISC 1989). The hydraulic forces are evaluated to ensure that the hydraulic system is capable of rotating the cradle and pump assembly to the vertical position (between 70{degrees} and 90{degrees}).

  18. Viscous Hydraulic Jumps Submitted by

    E-print Network

    Bush, John W.M.

    Viscous Hydraulic Jumps Submitted by Jeffrey M. Aristoff, Jeffrey D. Leblanc, Annette E. Hosoi, and John W. M. Bush, Massachusetts Institute of Technology We examine the form of the viscous hydraulic of height 2­10 mm. Elegaard et al.1 first demonstrated that the axial symme- try of the viscous hydraulic

  19. Hydraulic assist turbocharger system

    SciTech Connect

    Kobayashi, R.J.

    1992-05-19

    This patent describes a turbocharger system for supplying charge air to a combustion engine. It comprises a pair of turbochargers each having a first turbine and compressor mounted on a common shaft for concurrent rotation, the first turbine being adapted to be rotatably driven by exhaust gases from the combustion engine to rotatably drive the compressor to produce charge air for supply to the engine, the turbocharger further including a second turbine mounted on the shaft, the second turbine comprising an hydraulic turbine for rotatably driving the common shaft to rotatably drive the compressor; pump means for producing a supply of hydraulic fluid under pressure; conduit means for delivering the hydraulic fluid under pressure to the second turbine to rotatably drive the second turbine; electrohydraulic control valve means for regulating passage of the hydraulic fluid through the conduit means to selectively control rotatable driving of the shaft by the second turbine in accordance with engine operating parameters; and a common support frame having the pair of turbochargers and the control valve means and the pump means mounted thereon to define a substantially unitary package adapted for facilitated mounting onto the engine.

  20. Lock for hydraulic actuators

    NASA Technical Reports Server (NTRS)

    Wood, R. H.

    1981-01-01

    Two clamps hold rod in fixed extension from cylinder even when power is off, converting actuator into stiff structural member. Locked actuator is useful as mechanical support or linkage or as fail-safe device in case of loss of hydraulic pressure. Potential applications include manufacturing processes and specialized handling and holding devices.