Showing papers on "Dynamic braking published in 2004"

Method and device for braking a motor

Abstract: A method and apparatus for braking a motor has a braking circuit that intermittently shorts the windings of the motor to brake the motor. The braking circuit is powered by back EMF generated by the motor when power is disconnected from the motor.

Apparatus and method for controlling regenerative braking of an electric vehicle

Abstract: The method includes detecting a brake pedal operation. Thereafter, calculating a non-driven wheel braking force applied to a non-driven wheel of the electric vehicle according to the brake pedal operation. Subsequently, calculating a target braking force for a driven wheel corresponding to the non-driven wheel braking force. Then, calculating an available regenerative braking force for the driven wheel. The method then compares the target braking force and the available regenerative braking force for the driven wheel. The method also controls regenerative braking and hydraulic braking of the driven wheel on the basis of the comparison of the target braking force and the available regenerative braking force for the driven wheel.

An anti-lock braking control system for a hybrid electromagnetic/electrohydraulic brake-by-wire system

Abstract: This work presents a nonlinear sliding mode type controller for slip regulation in a braking event for a hybrid electromagnetic-electrohydraulic brake-by-wire system. The ABS controller modifies the brake torque command generated by a supervisory controller based on driver's command via brake pedal sensor. The brake torque command is then generated by closed loop actuator control algorithm to control the eddy current brake (ECB) and electrohydraulic brake (EHB) systems. The proposed control algorithm shows very good slip regulation in a braking event on low friction coefficient surfaces when compared with non-ABS braking. Usage of ECB resulted in a smooth ABS stop minimizing the NVH of current hydraulic ABS systems.

Automatic brake system for a vehicle

Abstract: An automatic brake system for a vehicle is disclosed. Based on a possibility that a potential collision with an obstacle preceding the vehicle can avoided by braking, and a possibility that the potential collision can be avoided by steering, the system automatically controls a braking operation for collision-avoidance. A condition of starting the automatic braking operation and a characteristics of the operation are determined based on calculation or estimation of a condition of the path where the vehicle is traveling, such as a relative speed, widths of spaces on sides of the obstacle, and steering characteristics.

Brake control apparatus

Abstract: A brake control apparatus is provided that distributes an engine braking torque Tbe to the front and rear wheels in accordance with an ideal braking torque distribution to suppress and prevent the tendency for one of either the front or rear wheels to lock when the engine braking torque operates. When the road surface friction state is a low friction state and the engine braking torque operates, the brake control apparatus derives an engine braking torque Tbe and distributes the engine braking torque Tbe to the front and rear wheels in accordance with the ideal braking torque distribution. In addition, when the engine braking torque reduction amount is small, the engine drives a generator connected to the engine. When the friction state between the wheels and the road surface is not in the low friction state, the generator attached to the engine is operated as a motor that supplements driving of the engine to reduce the engine braking torque of the engine.

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

Abstract: 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 simultaneously. Individual controller is designed for each subsystem and an integrated algorithm is constructed to coordinate these two subsystems. As a result, the integration of anti-lock braking and active suspension systems indeed enhances the system performance because of reduction of braking time and distance.

Control of regenerative braking during a yaw stability control event

Abstract: The present invention is a method and system to control regenerative braking during the operation of a yaw stability control system. The method and system use feedback control algorithms to monitor and dynamically modify regenerative and non-regenerative braking. The controller can use a simple proportional-integral-derivative feedback controller. A vehicle yaw stability control system can determine if a vehicle is experiencing an oversteer or understeer condition. The controller compares actual brake balance to a desired brake balance. The controller determines if the front axle wheels are overbraked relative to the rear axle wheels or if the rear axle wheels are overbraked relative to the front axle wheels as compared to the desired brake balance. The controller can adjust regenerative braking and non-regenerative braking levels according to the determinations.

Automotive steering control in a split-μ manoeuvre using an observer-based sliding mode controller

Abstract: Summary In this paper a sliding mode integral action controller and sliding mode observer are used to enhance vehicle stability in a split- µ manoeuvre. Anti-lock braking systems (ABS) have become an integral part of modern cars, and they have dramatically improved vehicle handling in braking manoeuvres. However, when a vehicle attempts to brake on a surface with uneven friction coefficient such as on wet or icy roads, a so-called split- µ scenario, the yaw moment generated by the asymmetric braking can prove demanding for an inexperienced driver. The controller presented hereworks in conjunction with a conventional ABS system to provide safe and effective braking through steer-by-wire. This paper extends previous state-feedback work by only using certain measurable quantities in the controller, estimating further signals by employing an observer.

Enhanced human-machine interface in braking

Abstract: Antilock brake system (ABS) technology with powerful electronic components has shown superior braking performance to conventional vehicles on test tracks. On real highways, however, the performance of the ABS-equipped car has been disappointing. The poor braking performance with ABS has resulted from the questionable design of the human-machine interface for the brake system. The goal of this study is to design brake systems that provide more intuitive brake control and proper braking-performance information for the driver. In this study automotive brake systems are modeled as a type of master-slave telemanipulator. Human force-displacement interaction at the brake pedal has a strong effect on braking performance. As a preliminary study in brake-system design, the characteristics of human leg motion and its underlying motor-control scheme are studied through experiments and simulations, and a model of braking motion by the driver's leg is developed. This paper proposes novel brake systems based on two new aspects. First, the mechanical impedance characteristics of the leg action of the driver are taken into consideration in designing the brake systems. Second, the brake systems provide the driver with kinesthetic feedback of braking conditions or performance. The effectiveness of the proposed designs in a combined driver-vehicle system is investigated using driving simulation.

On the Braking Behavior of Motorcycles

Abstract: This work presents a study on the braking style and its implications on motorcycle stability. First, a simplified motorcycle model is used for highlighting basic phenomena which occur during braking and for developing an ideal braking strategy. Then, braking maneuvers are analyzed using a detailed multi-body model, which takes into account all relevant characteristics of a motorcycle, such as geometry, mass and inertia distribution, non-linear suspension and tire properties. Simulations are repeated for dry and wet road conditions, showing that the correct braking style should change as the adherence conditions change, according to the suggestions given by the simplified model. Finally, stability analysis is carried out for different speeds, deceleration rates and braking styles, showing that a correct braking balance may significantly improves vehicle stability.

Method for operating multiple axle regenerative braking in an automotive vehicle

Abstract: A system and method for maximizing the post-ABS regenerative braking capability of an automotive vehicle having regenerative braking available for more than one axle determines the availability of surplus regenerative braking capacity on a first axle and then uses the surplus, if any, to satisfy the brake demand for another axle having insufficient regenerative braking capacity. This system restores regenerative braking without causing the regenerative braking to trigger a subsequent ABS event.

PID-Type Fuzzy Control for Anti-Lock Brake Systems with Parameter Adaptation

Abstract: In this research, a platform is built to accomplish a series of experiments to control the Antilock Brake System (ABS). A commercial ABS module controlled by a controller is installed and tested on the platform. The vehicle and tire models are deduced and simulated by a personal computer for real time control. An adaptive PID-type fuzzy control scheme is used. Two on-off conversion methods: pulse width modulation (PWM) and conditional on-off, are used to control the solenoid valves in the ABS module. With the pressure signal feedbacks in the caliper, vehicle dynamics and wheel speeds are computed during braking. Road surface conditions, vehicle weight and control schemes are varied in the experiments to study braking properties.

SIMULINK model of a quarter-vehicle with an Anti-lock Braking System

Abstract: • A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers.

Brake device for vehicle and brake control program for vehicle

Abstract: PROBLEM TO BE SOLVED: To provide a brake device for a vehicle capable of miniaturizing and reducing the weight of a hydraulic brake device and compensate insufficiency of braking force due to fluctuation of regenerative braking force by a regenerative brake device when regenerative braking force fluctuates by hydraulic braking force by the hydraulic brake device. SOLUTION: This brake device for the vehicle is provided with the hydraulic brake device capable of giving control hydraulic braking force to a wheel corresponding to a wheel cylinder by giving control liquid pressure formed by driving a pump irrespective of brake operation to the wheel cylinder, the regenerative brake device for generating regenerative braking force corresponding to a brake operation condition detected by a brake operation condition detection means for detecting a condition of brake operation in the wheel by a motor driving any of the wheels, and a braking force compensation means for compensating insufficiency of braking force due to fluctuation of regenerative braking force. COPYRIGHT: (C)2006,JPO&NCIPI

Vehicle braking control device for braking force distribution

Abstract: A braking control device for a vehicle executes braking force distribution (BFD) biased to front wheel in a manner compatible with Anti-skid control. In BFD control, braking force on rear wheels is held at a holding braking force and braking force on the front wheels is incremented beyond braking force requested by a braking action of a driver. After the starting of BFD control, further increase in the braking action is reflected in the front wheel braking force. Upon starting anti-skid control for either of the wheels during the execution of BFD control, an increment of the front wheel braking forces to be requested by BFD control is gradually decreased. Simultaneously, the holding of the rear braking force is released so as to compensate for the shortage of braking force on the front wheel. The gradual decrease of the braking force increment prevents a conflict of BFD and Anti-skid control.

Vehicular braking system

Abstract: PROBLEM TO BE SOLVED: To provide a vehicular braking system capable of suppressing fluctuation of the total braking torque when the braking torque applied to a wheel by a regenerative brake is shared by a hydraulic brake. SOLUTION: In a vehicular braking system to brake a vehicle through the cooperative control of a regenerative brake with a hydraulic brake, the tentative target hydraulic braking torque is determined based on the total required braking torque and the actual regenerative braking torque by S18-S22, the sharing gradient from the regenerative brake to the hydraulic brake is acquired based on the deceleration or the like of a vehicle body by S24, and the control delay correction is performed to the tentative target hydraulic braking torque by S26-S36 to determine the target hydraulic braking torque. In S38, the braking torque of the hydraulic brake is increased in a leading manner, and the hydraulic pressure follow-up regenerative control is performed, in which the regenerative braking torque is reduced while the total required braking torque is excessive thereby. COPYRIGHT: (C)2006,JPO&NCIPI

Braking hydraulic pressure control device for vehicle

Abstract: PROBLEM TO BE SOLVED: To make operation feeling better by securing an operation stroke of a brake operation member at the time of regenerative and cooperative brake control in a braking hydraulic pressure control device for a vehicle capable of executing the regenerative and cooperative brake control controlling the braking hydraulic pressure of a wheel braking mounted to a driving wheel so as to reduce the amount of frictional braking by the amount of the regenerative braking torque in reducing the speed. SOLUTION: In the braking hydraulic pressure control device for the vehicle, a stroke absorbing means 21A where a reservoir 12 and a control valve 22 for adjusting the stroke which is in a closed state in non-regenerative and cooperative braking but is opened in the regenerative and cooperative braking are connected to a master cylinder M. COPYRIGHT: (C)2006,JPO&NCIPI

Method for optimizing a braking sequence

Abstract: A method for optimizing a braking sequence in a vehicle with automatic transmission (3) and gearbox (9) and automatic cruise control, which cruise control controls acceleration and braking to achieve a set speed, taking into account the distance to the vehicle in front. Data simulations are carried out continually of how the vehicle will be driven in the future, for a set of different combinations of engine speed at which a gear change takes place, gear change step and braking sequence, and a braking sequence with associated gear change schedule is selected that will be optimal. The vehicle is equipped with at least two different braking systems, for example service brake and auxiliary brake (48, 6). The system selects to brake primarily with the braking system that has the least tendency to wear.

Automatic brake control device of vehicle

Abstract: PROBLEM TO BE SOLVED: To provide an automatic brake control device of a vehicle capable of achieving an automatic brake control without giving an uncomfortable feeling to a driver regardless of a stop position approaching path, on which the vehicle travels. SOLUTION: This device starts automatic brake control when a distance between a current point and a temporary stop point obtained from a navigation device becomes not more than a final required braking distance Lth x Klth. At that time, a final required deceleration change pattern, Pattfin(x) to be a target to follow control an actual deceleration of the vehicle is produced. The final required deceleration change pattern, Pattfin (x) is produced on the basis of a reference average deceleration change pattern, Pattnormave (J) corresponding to a stop position approaching path J, on which the vehicle is now traveling, among each of reference average deceleration change patterns respectively stored/learnt in a backup RAM every stop position approaching path in advance based on the actual braking operation by the driver. COPYRIGHT: (C)2006,JPO&NCIPI

Braking system for vehicle

Abstract: A braking system for a vehicle, including a braking device which puts brake on a vehicle; an operating device which includes an operating member that is operated by a driver of the vehicle in a braking force increasing direction, that is, an operating direction in which a braking force of the braking device is increased or in a braking force decreasing direction, that is, an operating direction in which the braking force of the braking device is decreased; and a control device which decides a target control value for controlling the braking device based on an operation state amount of the operating member and which controls the braking device based on the decided target control value, wherein the control device includes an operating direction-dependant target control value deciding portion which sets an increasing direction target control value that is the target control value when the operating member is operated in the braking force increasing direction, and a decreasing direction target control value that is the target control value when the operating member is operated in the braking force decreasing direction to values different from each other at least in part of a control range.

Silencing equipment for an air-cooling assembly

Abstract: Silencing equipment is provided for an air-cooling assembly in a off-road vehicle having wheels, traction motors, a power generating dynamic braking mode, resistor grids a resistor grid housing for dissipating the dynamic braking power and a blower. The grid housing includes an air inlet including noise-absorbing material. A conduit with noise-absorbing material is provided for directing cooling air from the inlet through a transition chamber to the blower and the resistor grid in the housing. A removable cover is provided in the conduit for accessing the air blower. The silencing equipment also includes an outlet with plurality of exhaust vanes.

Vehicle braking force control device with feedback communication between wheels

Abstract: A vehicle braking force control device for executing a follow-up (or servo) control of braking force for individual wheels is improved for canceling the difference of braking force between left and right wheels especially during transient condition of braking force variation due to the difference of input-output response characteristics in braking force generating apparatuses and components associated therewith in a braking system. In the inventive control device, a relation between actual values of braking force on left and right wheels, such as the difference between braking force or pressure values on the left and right wheels, is fed back to these braking force generating apparatuses through the modification of target barking force or pressure values. The modification amounts of the target values may be determined so as to keep appropriate braking force distribution among front and rear wheels.

Railway vehicle information control system

Abstract: PROBLEM TO BE SOLVED: To provide a railway vehicle information control system, by which predetermined accelerating force is appropriately obtained, when in an acceleration run, regardless of the number of vehicles, and holding braking torque is appropriately generated by main converters, when holding braking run SOLUTION: When power run or the holding braking run of the vehicles is required from a master controller 12, the vehicle information control system 17a inputs the mass of the vehicles, M1 to M5, from vehicle mass detecting devices 21a to 21e of brake controllers 16a to 16e of each vehicles 11a to 11e, calculates power running torque which runs the vehicles or the holding braking torque, assigns the power running torque to main converters 18b to 18d of each vehicles 11b to 11d, and assigns holding of braking torques to the main converters 18b to 18d and the brake controllers 16a to 16e, by which the power-running torque or the holding braking torque is appropriately generated by the main converters 18b to 18d, when braking run is held COPYRIGHT: (C)2006,JPO&NCIPI

Vehicular braking control device

Abstract: PROBLEM TO BE SOLVED: To provide a vehicular braking control device capable of jointly using a regenerative brake and a friction brake for braking each wheel, and preventing degradation of the braking force and generation of the vibration and squeaking attributable to the rust by removing the rust generated on a disk rotor in an early stage. SOLUTION: The vehicular braking control device has an in-wheel motor and a friction brake on each wheel, and jointly uses the regenerative braking force by the in-wheel motor and the friction braking force by the friction brake in the braking mode. The pressing force of the friction brake against a disk rotor is detected, the torque to the wheels is obtained from the current of the in-wheel motor (Step 12), generation of the rust on the disk rotor is determined (Step 13) based on the pressing force and the torque detected in Step 12, provision of the braking force by the regenerative brake is stopped when it is determined in Step 13 that the rust is generated on the disk rotor, and the braking is preferentially performed by the friction brake (Step 14). COPYRIGHT: (C)2006,JPO&NCIPI

Device and method for adjusting the pedal characteristic curve of a hybrid braking system during modified braking-force distribution

Abstract: A braking system for a vehicle is described, including a hydraulic service braking system and an electric service braking system having wheel brakes, to which braking pressure is applied when a brake pedal is operated. To maintain essentially constant vehicle braking behavior during a change in the braking-force distribution between the hydraulic and the electric service braking systems, it is proposed to provide a control unit, which is capable of varying the braking-force distribution and to equip the hydraulic service braking system with a braking pressure modulator that is controlled by the control unit and is able to effect a variable braking-force distribution as a function of the control by the control unit.

Braking force control apparatus and method for vehicle

Abstract: In braking force control apparatus and method for an automotive vehicle, a front-and-rear road wheel braking force distribution determining section determinatively distributes a front-and-rear road wheel braking force at a front-and-rear road wheel braking force distribution toward front and rear road wheel sides of the vehicle in accordance with a vehicular turning state to achieve the target deceleration and the vehicular deceleration developing section develops the target deceleration on the basis of the front-and-rear road wheel braking force distribution determined by the front-and-rear road wheel braking force distribution determining section.

Locomotive braking method, especially applying to emergency braking, whereby once failure of the electric brake is detected, by a measurement system, then the hydraulic brake is activated directly

Abstract: Method for braking a locomotive whereby, especially during emergency braking, first an electric brake and then if necessary a pneumatic brake is applied. The operation and effect of the electric brake is measured and if failure of the electric brake is detected, then the hydraulic brake is activated. The invention also relates to a corresponding locomotive braking device.

Fuel cell vehicle control unit

Abstract: PROBLEM TO BE SOLVED: To control the fluctuation of acceleration at the front and rear of a vehicle at the time when regenerative cooperative braking is changed to friction braking. SOLUTION: A cooperative regeneration braking control device 1 raises liquid pressure supplied to a brake, a friction braking device, in advance up to braking preparation liquid pressure before a braking status is changed from regenerative braking to the friction braking, and controls the braking in such a way as to limit regeneration amount by a motor, if the vehicle is put into the braking status when the charged state of a battery is equal to or larger than a second given value, which is lower than a first given value that stops power generation by a fuel cell. To achieve this control, the control device 1 is provided with a brake preparation liquid pressure calculating portion 4 that calculates the brake preparation liquid pressure, a brake liquid pressure calculating portion 5 that calculates the mutual conversion of the brake liquid pressure and friction braking amount by the brake, and a regenerative braking amount calculating portion 6 that calculates the regenerative braking amount by the motor and limits the amount (the amount of regenerative power generation) by the motor. COPYRIGHT: (C)2006,JPO&NCIPI

Process to regulate braking force at steerable front wheels in a stationary motor vehicle provides pulsed or single wheel braking during steering operations

Abstract: A process to regulate braking force at steerable, especially front, wheels in a stationary motor vehicle during a steering movement of these wheels comprises diminishing the applied force at the front wheels, at least in fixed operating conditions, either by a pulsed braking action or by braking one of the two wheels.