Abstract: A brake ECU determines whether or not interference-based vibration components are included in a vehicle body deceleration (DV) (steps S74, S76). Then, in the case of a positive determination (YES in step S74 or step S76), the brake ECU makes a comparison with when the determination is not positive, and revises a first deceleration determination value (DV_st) to be a larger value (step S79). If the vehicle body deceleration value (DV) exceeds the first deceleration determination value (DV_st) and a G sensor value (G) exceeds a second deceleration determination value (G_st) (YES in steps S84 and S89), the brake ECU initiates auxiliary control.

Abstract: In a regulating system and method of regulating the chassis of a motor vehicle, sensor data which are present for regulating the suspension and the damping of a vehicle body vehicle and describe the suspension state are forwarded to the regulating module of an antilock brake system. A state of the motor vehicle with regard to a brow situation can be determined from the sensor data. The sensor data or the state with regard to the brow situation are/is taken into consideration in the regulating module of the antilock brake system when determining control signals for regulating the brake pressure in brake apparatuses which are assigned to the wheels, in particular in the brake cylinders. This increases the driving safety considerably when driving over a brow and immediately after driving over a brow and increases the efficiency and reliability of the antilock brake system substantially in corresponding driving situations.

Abstract: A method for reducing or mitigating the effects of vibration in a vehicle brake system, particularly those that can lead to brake groan or other unwanted noise. According to an exemplary embodiment, when the vehicle brake system detects certain vibratory conditions, it makes slight braking adjustments (e.g., adjustments to fluid pressure, brake force, brake torque, etc.) that are aimed to address the brake groan. The vehicle brake system can then determine the effectiveness of the braking adjustments and, if need be, make additional braking adjustments. The method is particularly well suited for use with brake-by-wire systems, but can be used with a number of different vehicle braking systems.

Abstract: The frequency of an information signal indicative of a-vibration of a wheel detected by an acceleration sensor mounted to a wheel; or a change in the pressure of a gas in a tire detected by a pressure sensor installed in the tire, is analyzed. The band value of the obtained vibration spectrum or pressure change spectrum is detected, and a vibration level or pressure change level at the detected frequency band is compared with: a vibration level table showing the relationship between road friction coefficient ? and vibration level; or a pressure change level table showing the relationship between road friction coefficient ? and pressure change level, to estimate a road friction coefficient ?. Therefore, it is possible to estimate the value of road friction coefficient ? accurately and improve the safety of a car.

Abstract: To improve the control behavior of a brake system with anti-lock control (ABS) on the occurrence of road irregularities, a brief braking pressure reduction phase with a major braking pressure reduction on a wheel, followed by a high re-acceleration of the wheel, is interpreted as a road irregularity if the quotient of the duration of the braking pressure reduction and of the total duration of the pressure reduction phase multiplied by the re-acceleration of the wheel or the maximum value of the re-acceleration or if the acceleration variation or the maximum value of the acceleration variation exceeds predetermined limit values, and a braking pressure rise that is increased compared to the standard ABS control is caused as a result of detection of the road irregularity.

Abstract: An improved ABS control method incorporates entry criteria for initiating ABS control based on brake pedal position and rate of depression, adaptively adjusted by a reference pedal position corresponding to a predefined vehicle deceleration. A periodically-updated characterization of the relationship between brake pedal position and vehicle deceleration is used to establish the reference brake pedal position, and when insipient wheel lock is detected, the initiation of ABS control is delayed by an entry delay period that decreases with increasing rate of pedal depression and with the degree to which the pedal position exceeds the reference pedal position. In this way, the entry conditions are predicated primarily on the manner of brake pedal depression, with adaptive adjustment for variations in braking effectiveness.

Abstract: A method and a device for controlling the slippage at at least one vehicle wheel in a closed loop. In order to reduce an unacceptable slippage at at least one wheel, the braking force at this wheel is influenced and wheel vibrations are determined. Furthermore, the tendency of the characteristic of the slippage is ascertained during a vibration, and the braking force is influenced as a function of the ascertained tendency.

Abstract: To provide a technique capable of detecting lifting of a rear wheel of a two-wheeled vehicle correctly and rapidly. An estimated vehicle speed is generated by selecting the larger one of wheel speed Vf, Vr of a rear wheel and a front wheel, and attention is paid to an estimated vehicle deceleration which is computed based on the estimated vehicle speed and it is judged that lifting of the rear wheel has occurred when a degree of lowering of the estimated vehicle deceleration is a predetermined value or larger.

Abstract: A brake system for a vehicle having wheels. The brake system includes a brake housing and a flow chamber housing. The brake housing includes a friction element being adapted to move to engage a portion of thewheels to inhibitfor inhibiting rotation of the wheels. The flow The flow chamber housing includes a substantially circular flow chamber and a brake fluid line. The substantially circularchamber housing includes an enlarged flow chamber has a circumferential wall andhaving a peripheral wall and a pair of opposite walls. The enlarged flow chamber is fluidly interconnected to the brake housing for supplying fluid to the brake housing for moving the friction element.

Abstract: A method for braking force distribution control for a vehicle with a direct four wheel drive mode, which does not become an obstacle to an effective braking force and disconcert the driver's feeling. This method relates to a braking force distribution control for a vehicle during direct four wheel drive mode and under the condition that the anti-skid control is inhibited, which does not operate pressure reduction control or the amount of pressure reduction.

Abstract: A wheel velocity signal for each wheel detected by a wheel velocity sensor is input to a bandpass filter. Signals from frequency bands unrelated to the unsprung resonance are then removed from the wheel velocity signal and only signals from frequency bands related to the unsprung resonance are output. A road surface &mgr; gradient estimation device uses an online identification method to identify an damping ratio of a second order resonance model similar to a suspension—tire resonance model from the signal output from the bandpass filter. The road surface &mgr; gradient is then estimated from the identified damping ratio. The damping ratio of the second order resonance model corresponds to the road surface &mgr; gradient in the following manner: when the damping ratio is identified as being small, the road surface &mgr; gradient is estimated as being large; and when the road surface &mgr; gradient is identified as being large, the damping ratio is estimated as being small.

Abstract: 1. Spring suspension system, in particular for a machine.

Abstract: An antiskid brake system for an automotive vehicle is provided which includes a parameter determining circuit and a braking condition determining circuit. The parameter determining circuit determines a parameter reflecting on brake torque applied to a wheel of the vehicle. The braking condition determining circuit compares the phase of a change in speed of the wheel with the phase of a change in the parameter to determine a phase delay of the change in speed of the wheel and determines the braking condition based on the phase delay, thereby allowing a wheel skid used in the antiskid brake control precisely without employing parameters such as vehicle speed and wheel speed as employed in conventional antiskid brake systems.

Abstract: The speed variation of the driven wheels is analyzed in a method of recognizing critical drive train oscillations which require countermeasures during an (ABS) controlled brake maneuver. The occurrence of oscillations having a frequency typical of drive train oscillations is established. When oscillations with this frequency occur, the duration of the oscillating process is established on each individual wheel, or the number of the successive oscillations or semi-wave oscillations is counted. When a predetermined counter reading is reached, an oscillation recognition is indicated if, at that time, the vehicle acceleration is above a predetermined limit value and if oscillation recognition has not yet been triggered on the other driven wheel. To dampen the oscillations, switch-over to a special control is effected for a defined interval. The commencement of the special control prevents braking pressure reduction, the pressure is maintained constant, or at most a delayed pressure increase is allowed.

Abstract: In a wheel condition estimating apparatus for estimating a wheel condition in a wheel resonance system including a frictional characteristic between a tire and a road surface, a transfer characteristic of the wheel resonance system from the vibration input to the output response is expressed by a transfer function including, as an unknown component of a wheel condition, a physical quantity relating to ease of a slipping between the tire and the road surface, an output response with respect to the vibration input to the wheel resonance system is detected and the unknown component which substantially satisfies the detected output response is estimated on the basis of the transfer function.

Abstract: This relates to a brake force control apparatus that executes a brake assist control, which generates, when a driver performs an emergency braking, a brake force greater than that generated at a normal time. The brake force control apparatus is inhibited from being unnecessarily executed at the time of traveling a rough road or passing a step. When it is determined, based on an operation of a brake pedal, that an emergency braking is performed, it is determined whether the road on which the vehicle is traveling is a rough road (step 114). If the road is not rough, it is further determined whether the vehicle is passing a step (step 116). The brake assist control is executed only when it is determined that the vehicle is not passing a step (steps 118-126).

Abstract: A method of improving the control behavior of a controlled brake system, wherein the rotational behavior of the individual vehicle wheels is measured and evaluated for determining control quantities, and wherein slip threshold values for the commencement of the control are predetermined, includes that the slip threshold of a wheel is increased for a predefined time interval as a function of the acceleration after preceding instability in order to suppress the effects of road surface irregularities. This increase may be carried out in two steps as a function of the exceeded acceleration limit values.

Abstract: In an anti-lock brake control system, an actuator is controlled based on at least a slip rate determined in a slip rate calculating device and an output from a low-pass filter for filtering a wheel acceleration determined in a wheel acceleration calculating device, thereby switching-over the braking-pressure reducing, maintaining and increasing modes from one to another. The braking pressure-reduction control provided by an operation control device is terminated in response to the wheel acceleration determined in the wheel acceleration calculating device becoming equal to or larger than a preset value. Thus, it is possible to prevent an excessive pressure reduction during an anti-lock brake control on a road surface having a high coefficient of friction.

Abstract: A vibration damper can suppress squeals of a brake in a positive and reliable manner while consuming less electric power. The damper has a vibration detector for detecting vibrations of the brake, and a vibrator for applying vibrations to the brake pad based on a detection signal from the vibration detector. An actuator circuit for actuating the vibration detector and vibrator is connected to a car battery through a changeover switch and another switch. These switches are closed only if a brake switch is detecting that the brake is being applied and a vehicle stop detector is detecting that the vehicle is not moving. When the switches are closed, electricity is supplied to the actuator circuit, so that the vibration detector and vibrator are actuated by the actuator circuit. With this arrangement, the damper is kept deactivated when it is unnecessary or detrimental to apply vibrations to the brake. Since it is activated only when necessary, it consumes less electric power.

Abstract: A brake control device for detecting a rear lift-up state of a vehicle, during braking, after a determination that: the driving surface has a high .mu. value; a rear wheel velocity is greater than a maximum front wheel velocity; and the same rear wheel has an acceleration within a specified range. Once the rear lift-up state is detected, and reference vehicle velocity is decreased by a specified value.

Abstract: An anti-skid braking system for wheeled vehicles having fluid actuated brakes associated with the vehicle wheels. The anti-skid braking system includes speed sensors associated with the vehicle wheels, a scanning control device response to speed signals from the speed sensors to actuate a pressure dump device to periodically release the fluid pressure applied to the brake of any wheel which is determined, by detection of a predetermined level of relative slip between that wheel and the road surface to be about to lock. Later, the system, by detection, can re-apply the actuating pressure to that brake when the tendency of that wheel to lock has been reduced.

Abstract: To provide optimal braking force control using braking operation data, an ECU in a brake force control system detects a braking operation according to fluctuation components of wheel rotation. That is, the ECU calculates the wheel acceleration and sets a reference load level for the braking operation according to a road surface coefficient of friction at the wheel tire. When the amplitude of the wheel acceleration increases and exceeds the reference load level, the braking load is determined to be heavy. If the braking load is heavy, the ECU decreases the brake oil pressure of the wheel being detected. In this way, the slip ratio can be controlled around a peak road surface coefficient of friction.

Abstract: Under conditions which indicate all wheels are unstable, all have been in pressure decrease for a long time, and the vehicle reference velocity has been continuously negatively corrected for a long time, recovery are flags set on all wheels. If all recovery flags are set and four wheel drive axle oscillations are present and the reference velocity has not been in negative correction for too long, the gradient of the vehicle reference velocity is limited to a fixed lesser slope. If one or more recovery flags are set, other measures can be taken, including flattening of the vehicle reference velocity through gradual additions to the calculated vehicle acceleration, and giving longer pressure holds and delaying pressure increase. The recovery flag is reset separately on each wheel only when that specific wheel becomes completely stable.

Abstract: A braking force acting on the wheel is actuated by a very small amount at a resonant frequency of a vibrating system comprised of a vehicle body, a wheel, and road surface, and the amplitude of the resonant-frequency component of the wheel speed is detected. A gain in the amplitude of the resonant-frequency component of the wheel speed with respect to the amplitude of the very small actuation of the braking force is determined. A mean braking force is controlled to decrease when the gain is smaller than a reference value, and to increase when the gain is greater than the reference value.

Abstract: First and second signals representing unevenness of the roadway are generated for at least one wheel, and brake pressure is controlled using control parameters based on the second signal. The first signal is compared to a first threshold which is dependent on the second signal, and an extreme value signal which represents large impacts on the vehicle is generated when the threshold is exceeded. The control parameters are then adjusted so that the channels for controlling brake pressure at each controlled wheel are less sensitive.

Abstract: An anti-skid control for use in an automotive vehicle is comprised of a brake control device for adjusting braking force of each road-wheel of a vehicle, the brake control device being set to be initiated upon receipt of a condition, a detecting device being set to be initiated upon receipt of a condition, a detecting device for measuring a load applied to the vehicle, and a changing device for less sensitivity of the initiation of the brake control device as the load decreases. Even if an instantaneous decrease of the load occurs due to the vehicle's jumping motion or turning motion, an expected initiation of the brake operation can be prevented.