Abstract: A hydraulic bake system with electronic anti-lock control includes a multi-circuit braking pressure generator, electrically operable hydraulic valves, low-pressure accumulators which accumulate the pressure fluid that is withdrawn from the wheel brakes in the period of braking pressure reduction wheel sensors, and circuits are used to evaluate the sensor signals and to generate braking pressure control signals. The braking pressure in each wheel is controlled individually by the hydraulic valves. The filling ratio of the low-pressure accumulators or the residual volume is constantly determined and the pressure fluid discharge to the low-pressure accumulators is modified in the course of a control operation as a function of the length of the control and the filling ratio. Initially, there are no restrictions on the anti-lock function, while the rate of fluid flow is drastically reducted in the course of control.

Abstract: A kinetic characteristic control system performs a modifying process for modifying a standby control constant so as to, for example, decrease the standby start opening in correspondence with a calculated braking system control decrease amount x (step 230), a shift pattern characteristic modifying process for modifying a shift position change line so as to make a shift-up thereof easy (step 250), an EFI control amount modifying process for modifying a fuel injection amount, an air-fuel ratio, and an ignition timing (step 270), and a modifying process for a driving system TRC control performance (step 290). These modifying processes are intended for modifying the control constant, control amount, etc. so that the driving torque may decrease to thereby prevent the occurrence of excessive slippage of the drive wheels.

Abstract: A brake system control apparatus comprising: a sensor providing an output signal indicative of operator foot force on a brake pedal; an actuator coupled to wheel brake and controlling a wheel brake force applied by the wheel brake responsive to a control signal; a controller coupled to the sensor and the actuator and including a differentiator (60) receiving the output signal and determining a rate of change of the operator foot force on the brake pedal, a comparator (62) for comparing the rate of change to a predetermined minimum, wherein a rate of change above the predetermined minimum indicates a quick application of brake pedal force by the vehicle driver, a brake gain adjuster (64) for increasing a gain of the brake system when the rate of change is above the predetermined minimum, a brake command generator (72, 74) determining a control signal in response to the increased gain when the rate of change of brake force is above the predetermined minimum and responsive to a base gain when the rate of change

Abstract: When a threshold value is exceeded by the rate of change in the input pressure, an automatic braking operation is initiated. The threshold value becomes lower as the potential for danger increases.

Abstract: A process and a device for determining the application pressure of a brake mechanism for a vehicle are proposed, where a measure of the pressure in the brake system and a measure of the rotational speed of at least one of the wheels to be braked are detected, and where the time of application of the brake mechanism and thus its application pressure are derived from the change over time in this rotational speed.

Abstract: A back-up power assisted braking system substitutes an intermittently actuated secondary source of pressurized hydraulic fluid such as a traction control/anti-lock pump and motor (41) for the normal braking power assist upon the detection of a failure in the primary power assisted braking system. A failure may be detected in responsive to sensing simultaneous brake pedal (23) displacement and a lack of fluid flow for providing an abnormality signal. Also, a failure may be detected by sensing a predetermined difference between the commanded braking force (45) and the actual braking forces (38, 49). There is a pressure transducer (45) which provides an indication of brake pedal commanded braking force and a hydraulic circuit (43, 53 or 55, 51) interconnecting the secondary source outlet, the individual wheel brake actuators (14) and secondary source inlet.

Abstract: A vehicle brake cylinder pressure control apparatus wherein an amount of fluid flow into a reservoir is estimated based on vehicle deceleration and a pressure reducing time of the brake cylinder, while an amount of fluid flow from the reservoir is estimated based on a pumping time during which the fluid is pumped up from the reservoir by a pump, and the vehicle deceleration or an operating speed of a pump motor, so that an amount of the fluid stored in the reservoir is estimated on the basis of the amounts of the flow flows into and from the reservoir. Various parameters may be used in place of the vehicle deceleration, pumping time and motor operating speed, for estimating the amounts of the fluid flow into and from the reservoir and the reservoir fluid amount.

Abstract: A control system is provided for controlling the driving stability of a vehicle which has a steering angle and a plurality of brakes to which respective braking pressures are applied. Each brake has valves for adjusting the brake pressure applied to the brake, individually. A sensor determines the steering angle. A yawing moment controller, receives the steering angle, and determines a yawing moment that is applied to the vehicle to prevent an undesirable yaw angle, yaw rate or yaw acceleration. Distribution logic receives the output of the yawing moment controller and determines pressure adjustments that are applied to each brake, individually, to apply the yawing moment to the vehicle. A valve switch timing facility receives the pressure adjustments determined by the distribution logic, and calculates valve switching times which are used to open and close the valves of each brake, individually, so as to perform the pressure adjustments.

Abstract: In a sensor malfunction detecting system, if an absolute value of a difference between acceleration values obtained from outputs of at least two of a pressure sensor a torque sensor, and a speed sensor, and an acceleration sensor is determined to be out of a range of a corresponding prescribed value then a corresponding count value is incremented by "1". The above described operation is repeated until the count value exceeds a prescribed target value whereupon it is determined that one of the sensors is malfunctioning, and a sensor malfunction signal is output. Accordingly, failure of a vehicle control system which controls braking force, for example, based on the output from the sensors can be prevented, which leads to improved safety during driving. Further, a sensor malfunction detecting system can be provided at a low cost.

Abstract: During one or more braking processes, the application pressures of the wheel brakes and the characteristic brake values of the wheel brakes of at least one axle are determined. The application pressure represents the beginning of brake action at the wheels and can be determined from an inflection point in the curve representing brake pressure at the wheels as it increases in response to a driver's command, and further from the wheel velocity or a derivative thereof. The characteristic brake values are determined based on the brake pressure, the application pressure, and the deceleration of the vehicle. The application pressures and the characteristic brake values are stored for use in subsequent brake actions, in order to control the brakes so that wheels at each axle are uniformly braked.

Abstract: A deceleration control device for a vehicle receives signals from an acceleration sensor, a speed sensor, and a brake fluid pressure sensor to calculate a brake fluid pressure control value to output a control signal to a brake pressure fluid control device. The deceleration control device may include a first arithmetic unit for calculating an actual deceleration of the vehicle, a second arithmetic unit for calculating a speed of the vehicle, a third arithmetic unit for calculating a target deceleration, and a fourth arithmetic unit for calculating the brake fluid pressure control command value. The first arithmetic unit may be coupled to the acceleration sensor signal and the speed sensor signal, the second arithmetic unit may be coupled to either the speed sensor signal or output of the first arithmetic unit, and the third arithmetic unit may be coupled to receive signals indicative of a stepping force of a brake pedal or a distance between the vehicle and an obstacle.

Abstract: To determine the pedal force as a control quantity for a brake system with anti-lock control, the drive motor of a hydraulic pump is switched over to generator operation during braking with anti-lock control, and the magnitude of the generator voltage and its fade-out behavior is evaluated. The hydraulic pump serves to return the pressure fluid which was discharged from the wheel brake for pressure reduction, or it serves for the supply of auxiliary pressure. The approximate supply pressure depending on the pedal force can be determined by the generator voltage and the fade-out behavior.

Abstract: A method and a device for electronically controlling or adjusting a brake system of a vehicle is proposed, in which brake system the characteristic braking curve of the trailer is adapted to a prescribed characteristic braking curve of the towing vehicle, in order to minimize the longitudinal forces between a towing vehicle and a trailer during a braking process, in such a way that the braking of the entire road train takes place in accordance with the prescribed characteristic braking curve of the towing vehicle.

Abstract: Valves for maintaining pressure at the vehicle brakes are activated when the vehicle reference speed falls below a predetermined value, whether the pressure is supplied by the brake pedal or an ASR. The energy supply for the valves is prevented from being switched off while the pressure is maintained.

Abstract: A braking force control system for a motor vehicle, in which a hydraulic pressure control device controls a hydraulic pressure generated by the master cylinder or the pump, in such a way that a target braking torque (Nr in FIG. 1) is calculated from a target slip factor (Sr) and an actual slip factor (S), the target braking torque (Nr) is converted into a target braking hydraulic pressure (Pr), and that an estimative braking hydraulic pressure (P) currently under action is calculated by the use of a hydraulic pressure model, while the controlled variable of the hydraulic pressure control device is calculated from the estimative braking hydraulic pressure (P) and the target braking hydraulic pressure (Pr) by the use of a reverse hydraulic pressure model. Thus, the hydraulic pressure can be controlled in conformity with the actual motion state of the motor vehicle.

Abstract: Improvements in vehicle antilock braking systems of the type having an operator controlled master cylinder (11) and a second source (55, 57) of pressurized hydraulic fluid for selectively supplying rebuild pressure after an antilock event are disclosed. The improved system is selectively operable in one of three braking modes, a normal braking mode (119) where braking force is proportional to an operator brake pedal pressure, an enhanced anti-skid braking mode (69) where braking force may be maintained at a maximum nonskid level, and a conventional anti-skid braking mode (71) where braking force follows a cyclic pattern of fluid pressure bleed and build. The system includes circuitry (17, 19, 35, 37, 93, 95) for determining the speed of each wheel and an arrangement (59) operable independently of any vehicle wheels for determining vehicle deceleration. This comparison normally invokes the enhanced anti-skid braking mode.

Abstract: An antiskid control device which calculates an estimated fluid pressure of each of wheel cylinders under antiskid control in each control cycle so as to adjust a fluid pressure of each of the wheel cylinders on the basis of the estimated fluid pressure and behaviors of the wheels. The device includes a differential pressure detecting member which detects a difference between a fluid pressure of a master cylinder and the fluid pressure of each of the wheel cylinders so as to produce an output signal indicative of the difference between the fluid pressure of the master cylinder and the fluid pressure of each of the wheel cylinders. When the difference between the fluid pressure of the master cylinder and the fluid pressure of each of the wheel cylinders is found to be in the vicinity of zero, the estimated fluid pressure of each of the wheel cylinders is set to a predetermined value by stopping addition in calculation of the estimated fluid pressure.

Abstract: An anti-skid control system of a vehicle includes a wheel speed sensor for sensing a wheel rotation speed, a hydraulic pressure adjusting device for adjusting a brake pressure of hydraulic fluid of the control system, and an anti-skid brake controller for controlling the hydraulic pressure adjusting device based on the wheel rotation speed detected. The brake pressure is cyclically changed in accordance with a control cycle including at least a pressure reduction phase in which the brake pressure is reduced and a pressure increase phase in which the brake pressure is increased. A brake pressure control device detects the pressure reduction amount based on a wheel operation parameter. A brake pressure reducing action is repeatedly executed in the pressure reduction phase at a predetermined interval. Braking performance can be improved by use of the system of this invention.

Abstract: A frictional value between a motor vehicle tire and a road surface is determined for use in an ABS system or a traction control system. Various sensors at the automobile ascertain the vehicle speed and the brake pressure at individual wheels. The angular acceleration of the wheel is calculated from the angular velocity thereof. A wheel slip is calculated from the vehicle speed and from the angular acceleration. The dependency of the coefficient of friction is approximated from the wheel slip with a non-linear approximation equation. The current estimation value for the coefficient of friction is estimated with a recursive estimation algorithm from measurement values previously ascertained during a preceding measuring instant.

Abstract: An anti-skid brake control system (9) for a wheeled vehicle has a conventional continuous source of pressurized hydraulic fluid, a hydraulically actuated wheel rotation braking device which responds via a wheel brake valve (11) to applied hydraulic pressure to apply a braking force to a wheel of the vehicle, and an operator actuatable control (10, 12, 39) for varying the supply of hydraulic pressure to the wheel rotation braking device. The system is responsive directly to the operator actuatable control (10, 12, 39) for determining the deceleration (14) currently commanded by the operator and further dynamically determines a maximum permissible wheel deceleration (47) at a given time. The operator controlled supply of hydraulic pressure to the braking device is overridden in the event that the deceleration (14) currently commanded by the operator exceeds the maximum permissible wheel deceleration.

Abstract: Vehicle antilock braking systems having an operator controlled master cylinder (11) and a second source (55, 57) of pressurized hydraulic fluid for selectively supplying rebuild pressure after an antilock event are disclosed. The system is selectively operable in one of three braking modes, a normal braking mode (119) where braking force is proportional to an operator brake pedal pressure, an enhanced anti-skid braking mode (69) where braking force may be maintained at a maximum nonskid level, and a conventional anti-skid braking mode (71) where braking force follows a cyclic pattern of fluid pressure bleed and build. The system includes circuitry (17, 19, 35, 37, 93, 95) for determining the speed of each wheel and an arrangement (59) operable independently of any vehicle wheels for determining vehicle deceleration.