A method for checking the availability of a hydraulic fallback level in a power brake system with electronic slip control, an electronic control device, and a power brake system with electronic slip control. In normal operation, power brake systems perform braking procedures without a driver participating in building up braking pressure. A requirement for braking is detected by an electronic control device and associated with a braking pressure which is set by electrical control of the drive of a primary pressure generator. Power brake systems are often equipped with a secondary pressure generator, connected with the wheel brakes, in parallel with the primary pressure generator, which can be used to perform the building up of pressure at a hydraulic fallback level. For safety reasons, the availability of the hydraulic fallback level is checked at particular time intervals during normal braking operation of the power brake system.

A brake system may include an actuating device, in particular a brake pedal; a first piston-cylinder unit having two pistons subjecting the brake circuits to a pressure medium via a valve device, wherein one of the pistons can be actuated by the actuation device; a second piston-cylinder unit having an electric motor drive, a transmission at least one piston to supply at least one of the brake circuits with a pressure medium via a valve device; and a motor pump unit with a valve device to supply the brake circuits with a pressure medium. The brake system may also include a hydraulic travel simulator with a pressure or working chamber which is connected to the first piston-cylinder unit.

A vehicle control method includes first anti-lock braking system control which is executed focusing on a vehicle deceleration when determination is made that a road is a bad road based on wheel acceleration information, as compared with a case where determination is made that the road is not the bad road, and a second anti-lock braking system control which is executed to reduce a pressure increasing gradient of a brake hydraulic pressure as compared with that in the first anti-lock braking system control. The vehicle control method includes executing the first anti-lock braking system control in a case where a wheel has a recovering tendency from slip when an execution condition of the anti-lock braking system control is satisfied, and executing the second anti-lock braking system control in a case where the wheel has a slipping tendency when the execution condition of the anti-lock braking system control is satisfied.

An ESC 33 increases distribution of a braking force to rear wheels according to a reduction in a speed of a vehicle due to braking, and distributes the braking force so as to allow the vehicle to be kept stopped due to braking forces applied to the rear wheels when the vehicle stopped. Then, a second ECU holds the braking force by driving a parking mechanism with the vehicle kept stopped due to the braking forces applied to the rear wheels.

An ECU is formed of an ABS control device for controlling operation of a braking device when a slip ratio of wheels FR to RL becomes greater than a threshold, an automatic brake control device that controls operation of the braking device based on information on surroundings of the vehicle, and the threshold changing device that changes the threshold at which the braking device is activated by the ABS control device so that the threshold when the braking device is being operated by the automatic brake control device is smaller than the threshold when the braking device is not being operated by the automatic brake control device.

A method, for a trailer brake control device of a vehicle trailer with an electric drive, includes receiving at least one acceleration request signal with a requested positive acceleration or a requested negative acceleration and further receiving a status signal with at least one status variable of the electric drive of the vehicle trailer. The method also includes generating, with a controller of the trailer brake control device, at least one brake actuation signal for at least one friction brake of the vehicle trailer and a torque request signal for the electric drive, each based on the at least one acceleration request signal and the status signal. Furthermore, the method includes outputting the brake actuation signal and the torque request signal via at least one output and/or at least one interface of the trailer brake control device.

A control unit for controlling an upstream braking actuator for generating upstream pressure and a downstream braking actuator for controlling braking pressures of four wheels using the upstream pressure is configured to, when a braking pressure of any wheel cannot be reduced, perform backup control so that the target upstream pressure becomes the target braking pressure of the relevant wheel, and is configured to, when performing anti-skid control in a situation where automatic braking and backup control are being performed, control the target upstream pressure such that the target upstream pressure becomes a target upstream pressure for the automatic braking when the target upstream pressure is the target braking pressure for the relevant wheel, and such that the target upstream pressure becomes the target braking pressure for the anti-skid of the relevant wheel when the target upstream pressure is not the target braking pressure of the relevant wheel.

The invention relates to a method for improving the control behavior of an electronic motor vehicle braking system which comprises at least a slip control function. Wheel dynamic information which is evaluated as a criterion for initiating a control intervention is used individually for each wheel and is compared with control thresholds for a pressure reduction phase, a pressure maintenance phase, and a pressure buildup phase for generating corresponding braking torques by means of a vehicle braking system. According to the invention, the expected acceleration change of a vehicle wheel is calculated from a pressure change at said wheel, said pressure change being caused by a control intervention; the actual acceleration change at the vehicle wheel, said acceleration change being caused by the pressure change, is determined from measured wheel speeds as wheel dynamic information; and the control behavior of the slip control is adapted when the actual acceleration change deviates from the expected acceleration change by a defined degree such that the deviation is minimized.

A method for decelerating a vehicle combination including a towing vehicle having a towing vehicle brake system and at least one trailer vehicle having a trailer brake system with an anti-lock brake system includes applying, by the towing vehicle brake system, a brake pressure to pneumatically operable wheel brakes of the towing vehicle according to a desired deceleration specified by a driver, and providing, by the towing vehicle brake system, a trailer brake pressure for the trailer brake system of the at least one trailer vehicle. An electronic brake control unit of the towing vehicle brake system: detects a current actual vehicle deceleration value continuously compares the current actual vehicle deceleration actual value with a maximum deceleration, and, when the current actual vehicle deceleration value reaches or exceeds the maximum deceleration, limits the brake pressure and provides an information signal.

Various antilock braking systems, devices, and methods using sensorized brake pads are disclosed. In some embodiments, the present disclosure provides a method for improving the performance of an antilock braking (ABS) and anti-slip regulation (ASR) system of a vehicle. The method can include detecting the actual value of the coefficient of friction (e.g., between a tire and the ground), updating the coefficient of friction during braking using the braking torque data derived from at least one braking pad of each wheel, and adjusting brake force. For example, the brake force can be adjusted as a function of and/or to be approximately equal to the value of the actual tire-road friction during braking.