Showing papers on "Dynamic braking published in 2001"

Circuit for controlling dynamic braking of a motor shaft in a power tool

Abstract: A circuit for providing a braking force to a power tool is provided comprising a motor adapted to rotate a drive shaft in a power tool, a power supply electronically connected to the motor, and a braking module, located between the motor and the power supply, for applying a current limited braking force to the motor when the power supply is disconnected to the motor.

Regenerative braking system for a batteriless fuel cell vehicle

Abstract: A regenerative braking system and method for a batteriless fuel cell vehicle includes a fuel cell stack, a plurality of ancillary loads, and a regenerative braking device that is coupled to at least one wheel of the vehicle The regenerative braking device powers ancillary loads when the vehicle is coasting or braking The fuel cell powers the loads when the vehicle is accelerating or at constant velocity The regenerative braking device dissipates power in an air supply compressor when the vehicle is traveling downhill to provide brake assistance The compressor can be run at high airflow and high pressure to create an artificially high load A bypass valve is modulated to adjust the artificially high load of the compressor A back pressure valve protects the fuel cell stack from the high airflow and pressure A controller controls a brake torque of the regenerative braking device as a function of vehicle speed and modulates the bypass valve

Auxiliary drive and automobile equipped with the same

Abstract: There are included a first motor-generator; speed change device disposed between an engine and a first wheel drive shaft; demanded braking force detection device for detecting braking force demanded by the driver; engine braking force calculation device for calculating engine braking force; and regenerative braking force calculation device for calculating regenerative braking force resulted by regenerative power generation of the first motor-generator. Gear ratio or shift points of the speed change device is controlled on the basis of information from the demanded braking force detection device, the engine braking force calculation device and the regenerative braking force calculation device.

Vehicular brake control apparatus and vehicular brake control method

Abstract: A vehicle is equipped with a coupling such as, for example, a center differential or a variable clutch, that transmits a driving force from an engine to a front-wheel drive shaft and a rear-wheel drive shaft while allowing a difference in rotational speed therebetween and a brake controller that individually controls braking forces to be applied to wheels in accordance with a running state of the vehicle. A vehicular brake controller prohibits braking force control from being started if the coupling is in its locked state or when the coupling causes a relatively great connecting strength to exist between the front-wheel and rear-wheel drive shafts. While braking force control is being performed by the brake controller, braking force control is continued even if there is a command to cause the coupling to be locked or to achieve the great coupling strength.

Adaptive powertrain braking control with grade, mass, and brake temperature

Abstract: A method and apparatus for adapting powertrain braking to mass, grade, and brake temperature. Vehicle mass is determined using a vehicle speed sensor and an tractive effort model based on engine-torque delivered, torque converter multiplications, and transmission ratio and tire rolling radius effects. Road grade is continuously calculated and altitude change is calculated based on grade and distance traveled. To achieve an ideal amount of powertrain braking, powertrain braking is directed towards a designed coast performance target based on deceleration as a function of vehicle speed. Fuzzy logic is used to evaluate driver intentions, grade load conditions, terrain conditions, brake conditions and other vehicle information to determine the actual, optimal powertrain braking control. A real time brake thermal model is developed to provide increased powertrain under extreme brake conditions. The powertrain braking efforts are limited when restricted by available tractive efforts.

Braking force control apparatus and method of motor vehicle

Abstract: A braking force control apparatus and method control a braking force of a motor vehicle that has (a) regenerative braking devices for front wheels and rear wheels, respectively, and (b) a friction braking device for each of the front wheels and the rear wheels. A target braking force of the front wheels and a target braking force of the rear wheels are calculated, based on a braking requirement made by a driver of the vehicle and a ratio of braking forces of the front wheels and the rear wheels. Initially, the regenerative braking devices are controlled to generate regenerative braking forces at the front wheels and the rear wheels, and then, if necessary, the friction braking device is controlled to generate a friction braking force at each of the front wheels and rear wheels, so that a total braking force applied to the front wheels and a total braking force applied to the rear wheels are controlled to the front-wheel target braking force and the rear-wheel target braking force, respectively.

Railway locomotive brake controller

Abstract: An integrated locomotive braking and ECP braking control on a lead locomotive for implementing braking effort on all locomotives in a manner relative to braking effort applied on ECP freight cars. On the lead locomotive, a data interface can be established between an head-end-unit and a brake controller. The head-end-unit can electrically signal each ECP freight car to carry out braking commands. The integrated brake control can include a CPU, as part of either the brake controller or the head-end-unit, which can be programmed to provide braking effort on the lead locomotive relative to the braking effort applied on the ECP freight cars. The braking on the lead locomotive is implemented by the brake controller by controlling the independent brake relative to the braking effort commanded on the ECP freight cars. The independent brake on non-ECP trailing locomotives is connected to the lead locomotive independent brake via a standard independent brake pneumatic connection. As a result, the same braking effort applied on the lead locomotive via the independent brake is automatically implemented on the non-ECP trailing locomotives via the independent brake pneumatic connection such that all locomotives are braked relative to braking on the ECP freight cars.

Back-up braking in electro-hydraulic (EHB) braking system

Abstract: An electro-hydraulic braking system of the type which operates normally in a brake-by-wire mode wherein hydraulic pressure is applied to braking devices at the vehicle wheels in proportion to the driver's braking demand as sensed electronically at a brake pedal (10), and which, if the brake-by-wire mode should fail, operates in a push-through mode wherein hydraulic pressure is applied to the braking devices at the vehicle wheels by way of a master cylinder (34) coupled mechanically to the brake pedal (10), the system including also an electric parking braking means for enabling the braking devices to be actuated for parking braking purposes but which is also arranged to be activated to supplement push-through braking in the event of failure of the break-by-wire mode. Electro-hydraulic braking at the rear axle of the vehicle is allowed only when a control unit (13) of the electro-hydraulic braking system has confirmation that the electric parking means is in a satisfactory operational state.

Method and system for controlling brake equipment which can be activated when a motor vehicle is stationary

Abstract: The present invention provides a method and a system for controlling a braking equipment of a motor vehicle in order to activate the braking equipment at a standstill of the motor vehicle such that braking forces are built up which are necessary to keep the motor vehicle in a state of standstill. To this end it is established on the basis of vehicle movements whether the vehicle is at a standstill. If vehicle movements are detected that cannot occur during driving modes of the motor vehicle, the motor vehicle is in a state of standstill. Subsequently, the braking equipment, and in particular a holding brake mechanism included in the braking equipment, are activated. In order to provide braking forces keeping the motor vehicle at a standstill also when it is on a slope, the braking equipment, and in particular the holding brake mechanism, are controlled in response of the vehicle inclination present in the state of standstill.

Autonomous emergency braking system

Abstract: An autonomous emergency braking system includes an accelerator pedal operated by the driver coupled to a braking system and used to control the overall vehicle speed. When a forward detection apparatus detects an imminent contact, the braking system automatically applies braking force to the vehicle while the vehicle engine speed is reduced. The amount of brake force applied is a continuous function of relative speed, relative distance, collision probability and target classification. The braking force may be reduced when the driver or passenger are unbuckled or may be disabled if the driver applies full throttle.

Control apparatus and method of vehicle braking and driving force

Abstract: A braking and driving force control apparatus and method are for a vehicle having a frictional braking device for applying a braking force individually to each wheel and a regenerative braking device for generating a common braking force to a plurality of wheels. A target braking force is calculated on the basis of a driver's braking operation or traction control. The regenerative braking device is controlled so as to achieve the smallest target braking force of the target braking forces of the plurality of wheels. The frictional braking device is controlled so as to achieve the target braking force of another wheel, different from the wheel having the smallest target braking force, in cooperation with the regenerative braking device. Thus, the efficiency of regenerating energy is enhanced.

Back-up braking in vehicle braking systems

Abstract: A vehicle braking system comprising an electro-hydraulic braking system of the type which operates normally in a brake-by-wire mode wherein hydraulic pressure is applied to braking devices at the vehicle wheels (18 a-d) in proportion to the driver's braking demand as sensed electronically at a brake pedal (10), and which, if the brake-by-wire mode should fail, operates in a push-through mode wherein hydraulic pressure is applied to the braking devices at the vehicle wheels (18) by way of a master cylinder (34) coupled mechanically to the braked pedal (10), and an electric parking braking system for enabling the braking devices to be actuated for parking braking purposes. For supplementing the push-through braking provided by the electro-hydraulic braking system in the event that the brake-by-wire mode has failed, it is arranged that the operation of the brake pedal (10) by the driver also causes operation of the electric parking braking system.

Blended electrical/friction braking system with electric brake feedback monitor and method of use thereof

Abstract: A blended electrical/friction braking system includes an electric brake feedback monitor which monitors a first signal corresponding to an electric brake effort request of an electric motor of an electrically powered vehicle. The electric brake feedback monitor detects one or more electrical conditions of the electric motor during electric braking and selectively supplies/terminates the first signal to/from a brake controller as a function of the first signal and the one or more electrical conditions. In response to termination of the first signal thereat, the brake controller causes a friction brake of the vehicle to assume the entire braking effort of the vehicle.

Method for monitoring the emergency braking capability of an electrohydraulic braking system

Abstract: The invention relates to a method for monitoring the emergency braking capability of an electrohydraulic braking system (EBS), in which the braking pressure in the wheel brakes (8 - 11) is generated during normal operation using a pressure source containing a hydraulic pump (18), an accumulator (16) and hydraulic valves. During emergency braking, the system switches to using the penetration factor from a main cylinder (1) to the wheel brakes (8 - 11). The method is characterized in that at each initialization of the braking system, the emergency braking function is tested using the steps described in claim 1.

Method and system for controlling stand-by braking torque applied to automotive vehicle

Abstract: The present invention pertains a method and a system for controlling a stand-by braking torque applied to an automotive vehicle under a condition of approaching or following an obstacle preceding the vehicle, the automotive vehicle having a powering system for applying a driving torque to the vehicle in response to an operator power demand. A brake controller executes a series of instructions for determining a variable indicative of dynamic situation of the vehicle, for sampling the determined values of the dynamic situation indicative variable immediately before an operator braking action to reduce the speed of the vehicle is imminent, for using the sampled values of the dynamic situation indicative variable as a basis to establish a parameter, and for using the established parameter as a basis to determine a target value of stand-by braking torque.

Method of diagnosing a vehicle brake system using brake pedal position and vehicle deceleration

Abstract: An improved method of diagnosing conditions of a vehicle braking system that degrade the braking effectiveness informs the driver of the condition so that repair or adjustment can be timely made. The relationship between brake pedal position and vehicle deceleration is determined during a calibration interval to construct a calibration table of brake effectiveness, and then periodically over the life of the braking system to develop a current brake effectiveness table. Braking system abnormalities that impair the braking effectiveness are diagnosed by analyzing the table values.

Regenerative braking on an electrical vehicle when towed

Abstract: Regenerative braking is actuated in an electrical vehicle during towing of the vehicle to recharge the battery and brake the vehicle. When a driver of a towing vehicle depresses the brakes of the vehicle ( 202 ), the electrical vehicle applies regenerative braking in proportion to a braking signal from the towing vehicle ( 206 ). Also, regenerative braking is applied to the electrical vehicle when the vehicle is inadvertently disconnected from a connector ( 110 ) that couples the electrical vehicle to the towing vehicle ( 208 ).

Driver augmented autonomous braking system

Abstract: An enhanced autonomous emergency braking system includes an accelerator pedal operated by the driver and used to control the overall vehicle speed. When a forward detection apparatus detects an imminent contact, the braking system automatically applies braking force to the vehicle while the vehicle engine speed is reduced. The amount of brake force applied is a continuous function of relative speed, relative distance, collision probability and target classification. The braking force may be reduced when the driver or passenger are unbuckled or may be disabled if the driver depresses the accelerator pedal by a predetermined amount. In addition, the amount of brake force applied by the driver is amplified to further enhance braking performance.

Braking control device for rail vehicle with electric and pneumatic brakes uses controlled magnetic valve for selectively suppressing function of pneumatic brake

Abstract: The braking control device has a magnetic valve (1,2) for suppressing the braking function of the pneumatic brake, its control input (3) coupled to a switching device (6,7), controlling the magnetic valve in dependence on the momentary braking provided by the electric brake and the current amplitude of the electric drive motor.

Emergency braking control with an observer-based dynamic tire/road friction model and wheel angular velocity information

Abstract: A control scheme for emergency braking of vehicles is designed. The scheme utilizes a LuGre dynamic friction model to estimate the tire/road friction. The control system output is the pressure to the braking system, and is calculated using only the wheel angular speed information. The controller utilizes estimated state feedback control to achieve near maximum deceleration. The state observer gain is calculated by using linear matrix inequality (LMI) techniques. This system has two advantages when compared with an antilock braking system (ABS), it generates less chattering during braking and produces a source of a priori information regarding safe spacing.

Method and device for controlling the braking equipment of a motor vehicle

Abstract: The invention relates to a method and a device for controlling the braking equipment of a motor vehicle. To this end, an operating state of a motor vehicle is determined, whereby the motor vehicle goes from one state during which the speed of said motor vehicle is different from zero, into another state during which the vehicle is stationary. If one such transition from a driving state to a stationary state is determined, the braking equipment of the motor vehicle is controlled in such a way that brake forces are produced which are appropriate for bringing the motor vehicle into a stationary state and/or assisting the driver of the vehicle. Furthermore, brake forces required to keep the vehicle stationary can be produced in the stationary state. The invention also enables the driver of a vehicle to be assisted when starting a motor vehicle. To this end, an operating state of the motor vehicle is detected, whereby said motor vehicle goes from a stationary state to a driving state. In the presence of one such operating state, the braking equipment of the motor vehicle is controlled in such a way that the brake forces produced by the braking equipment in the stationary state are reduced in such a way that a transition into the driving state is achieved and/or the driver of the vehicle is assisted.

Brake-actuating steering and braking control system for tracked vehicles

Abstract: A brake-actuating steering and braking control system for a tracked vehicle is provided with a braking control subsystem, a steering control subsystem, and right and left side brake-actuating subsystems. The braking control subsystem includes a brake pedal and is connected to brake mechanisms of each brake-actuating subsystem. A user may depress the brake pedal to apply a braking force to right and left side track assemblies of the tracked vehicle via the brake mechanisms to thereby slow or stop the tracked vehicle. The steering control subsystem includes a steering wheel and is connected to each of the brake mechanisms. The user may rotationally displace the steering wheel, which applies a braking force to the track assembly corresponding to the direction of rotational displacement of the steering wheel via the corresponding brake mechanism to thereby turn the tracked vehicle.

Method for terminating a braking intervention of an adaptive cruise control system of a motor vehicle

Abstract: A method for terminating a braking intervention of an adaptive cruise control system of a motor vehicle. The braking intervention is terminated in accordance with a predefined algorithm in response to the driver overriding of the adaptive cruise control system. In this context, the algorithm is formed in such a manner that a jerk-free transition from braking to acceleration of the motor vehicle is ensured, thus increasing the ride comfort. The transition from braking to acceleration preferably takes place in accordance with a linear function. Provision can also be made for stepwise functions. To prevent the braking operation from being terminated prematurely by an inadvertent actuation of the accelerator, provision is made for a threshold value to be adjusted for the accelerator for a desire of the driver to accelerate. This threshold value is dependent on the deceleration during braking. The higher the braking deceleration is, the more heavily the driver must operate the accelerator to initiate the acceleration process. In the case of a low deceleration, the threshold value is lower, so that it suffices to step more lightly on the accelerator to bring about an acceleration of the motor vehicle.

Dynamic side to side brake proportioning

Abstract: A dynamic side-to-side braking method is disclosed. First, when the vehicle is in a combined braking and cornering maneuver, a desired braking force among tires of a vehicle is determined. Second, a brake force distribution of the desired braking force among the tires is determined. The brake force distribution is approximately proportional to a normal force distribution among the tires during the combined braking and cornering maneuver by the vehicle. When the vehicle excludes an active steering system, front or rear, the brake force distribution is determined as a function of a feedback correction to counterbalance a portion of a yaw moment experienced by the vehicle during the combined braking and cornering maneuver. When the vehicle includes an active steering system, front or rear, a steering correction is determined to counterbalance a portion of the yaw moment experienced by the vehicle during the combined braking and cornering maneuver.

Braking assistance function improvement method adjusts relationship between accelerator pedal movement and delivered engine torque during emergency braking

Abstract: The method has a given braking force provided automatically upon indication of an emergency braking situation by detection of maximum braking by the driver or a critical travel situation, with adjustment of the relationship between the movement of the accelerator pedal and the torque delivered by the engine.

Method and device for ensuring the braking effect of brake actuators in a vehicle

Abstract: A method of ensuring the braking effect of brake actuators in a vehicle is described, each brake actuator having first and second components for producing the braking effect, where films on the first components which would interfere with the deployment of the braking effect are removed. In this method, when an activation condition is met, the brake actuators are activated to remove the films so that the second components are applied to the first components, thereby setting the vehicle deceleration so that little or no deceleration is perceived by the driver. In checking on whether the activation condition is met, a quantity describing operation of the accelerator pedal is taken into account.

Degenerative brake device for hybrid vehicle

Abstract: PROBLEM TO BE SOLVED: To perform regenerative braking by effectively using regenerative power, even in a fully charged condition of a battery or in a condition close to it. SOLUTION: When a vehicle is decided to be in braking and further when a battery is decided incapable of being charged, an engine is stopped and an on-vehicle auxiliary apparatus is driven by driving a second motor by the regenerative power from a first motor. In this way, even if the battery is in a fully charged condition or in a condition close to full charge, a regenerative braking can be performed by effectively using the regenerative power, and the fuel consumption of a hybrid vehicle can be reduced comprehensively, in addition to stopping of the engine during braking.

Method and device for monitoring the effectiveness of vehicle braking systems

Abstract: The invention relates to a method and to a device for monitoring the effectiveness of vehicle braking systems. To this end, a braking request of the driver is compared with the reaction of the vehicle prompted by this request and to recognize, by sequential examination of a plurality of response criteria, any malfunctions that might arise and to initiate an emergency or safety braking.