Abstract: A method and apparatus for braking a vehicle having a vehicle brake system with a brake control device, and an engine whose torque is transmitted via a transmission to driven wheels. When there is a malfunction of the braking system and a demand for a braking operation, the transmission ratio is increased by a transmission control unit, which activates the transmission, to produce increased braking torque at the driven wheels.

Abstract: An automatic brake and steering system and method for a vehicle contains a sensor unit for sensing vehicle state and characteristic variables, and ambient conditions. Furthermore, a control unit and actuator devices are provided for setting the vehicle brake system and/or the vehicle steering system. In order to be able to carry out automatic avoidance maneuvers with maximum safety, an avoidance route is determined if there is an obstacle in the path of the vehicle. Thereby, if there is a further obstacle on the avoidance route, the strategy for determining the avoidance route is applied once more. If it is not possible to find a collision-free avoidance route, that route on which the difference between the remaining braking distance and the remaining distance from the obstacle is smallest is selected.

Abstract: An automatic brake and steering system for a vehicle containing a sensor unit for sensing vehicle state variables and vehicle characteristic variables and ambient conditions. Furthermore, a control unit and actuator devices are provided for setting the vehicle brake system and/or the vehicle steering system.

Abstract: A steering system functions in accordance with the “steer by wire” concept and has a normal operating system without positive coupling between the steering handle and the steered vehicle wheels, as well as an emergency operating system, which functions with positive coupling between the steered vehicle wheels and the steering handle. An auxiliary operating system is additionally provided, which, in response to malfunctions of the normal operating system, assumes its tasks and, in a transitional phase, adapts the performance characteristics of the steering system to those of the emergency system, which is switched on upon conclusion of the transitional phase. Thus, at the transition from the normal operating system to the emergency operating system, the driver is given time to become accustomed to the other steering performance.

Abstract: A self-testing sensor (especially to measure an angular rate or acceleration) includes a resonant structure, an actor unit configured to excite the structure to a first periodic vibration, a piezoresistive element configured to generate an output signal that depends on the measured quantity, and an isolator configured to isolate a test signal component from the output signal, whereby the test signal component is generated by a second periodic vibration of the structure superposed on the first vibration. A device for self-testing a sensor includes an isolator configured to isolate a test signal component superposed on a useful signal component from the periodic output signal of the sensor, and it includes a comparator configured to compare the test signal component with a predefined value or a test signal fed to the sensor. For the self-test, a second periodic vibration is superposed on a first vibration of the structure, and an output signal containing information on the measured quantity is determined.

Abstract: A steering system functions in accordance with the “steer by wire” concept and has a normal operating system without positive coupling between the steering handle and the steered vehicle wheels, as well as an emergency operating system, which functions with positive coupling between the steered vehicle wheels and the steering handle. An auxiliary operating system is additionally provided, which, in response to malfunctions of the normal operating system, assumes its tasks and, in a transitional phase, adapts the performance characteristics of the steering system to those of the emergency system, which is switched on upon conclusion of the transitional phase. Thus, at the transition from the normal operating system to the emergency operating system, the driver is given time to become accustomed to the other steering performance.

Abstract: A steering system for motor vehicles, has a steering handle, for example steering handwheel, capable of being operated by the driver. A steering actuating drive provides for the steering adjustment of steerable vehicle wheels. A steering-angle desired-value encoder is capable of being operated by the steering handle, and a steering-angle actual-value encoder operates via the steerable vehicle wheels. A regulating and control arrangement operates the steering actuating drive as a function of a comparison of the desired and actual values of the steering angle. The risk of a collision between a vehicle equipped with the steering system and an obstacle is reduced, and the steering system is suitable for steer-by-wire operation by equipping the steering system with collision prevention apparatus which determine steering angles (collision steering angles) making a collision possible between the motor vehicle and an obstacle.

Abstract: A braking-force control system and method is provided for a road vehicle having an electrically controllable four-circuit brake system. The braking forces generated by the individual wheel brakes can be adjusted in a wheel-specific way. Adjustment devices on a chassis vary the normal forces acting on the vehicle wheels, with at least one normal-force adjustment device being provided per vehicle wheel. The adjustment devices are configured so that, for the most part, the weight of the vehicle can be supported on one of the front wheels and on the rear wheel of the vehicle which is arranged diagonally opposite the latter. The braking force generated by a front-wheel brake and the rear-wheel brake which lies opposite the latter viewed along the diagonal of the vehicle, corresponds overall to the vehicle weight multiplied by a maximum coefficient of friction which is effective between the carriageway and the braked wheels.

Abstract: A system generates a brake pressure with a pump which delivers a volume into the chamber of a master brake cylinder and builds up a pressure which is used by at least one additional assembly, particularly a power-assisted steering system. The system has at least one distributing and throttling element for admitting a definable pressure to the chamber of the master brake cylinder and/or the additional assembly. The one or more distributing and throttling elements can be triggered, as a function of the brake pedal position and/or of driving condition values and/or of operating values of the vehicle, such that the chamber and/or the additional unit can be acted upon by a pump generated adjustable pressure.

Abstract: A brake system is provided in which, in the normal operation, the brake pressure in the wheel brake cylinders is generated in a power-assisted manner and the master brake lines are closed by change-over valves. During a functional disturbance, the brake pressure in the wheel brake cylinders is built up by way of a master brake cylinder, such that, when the brake pressure control device operates normally also when the switching valves are closed the brake pedal can carry out a pedal travel and, on the other hand, when there are functional disturbances of the brake pressure control device, at most with a slight idling path of the brake pedal, by the operation of the brake pedal in the master brake cylinder and the wheel brake cylinders, a brake pressure can be generated in a conventional manner.

Abstract: For the determination of the friction/slip characteristics of the tires of a road vehicle which is equipped with an antilock system designed for an individual wheel control, in an initial phase of a controlled braking, only the wheel brake of an individual vehicle wheel is acted upon by brake pressure and the latter is dimensioned so that the result is the initial retardation in accordance with the driver's wish. During this initial test phase of the braking, the absolute brake slip .lambda..sub.B as well as the friction utilization .mu..sub.B linked therewith is continuously determined as soon as, as a result of just the braking of the test wheel, the vehicle retardation z increases no further and/or the braked vehicle wheel is more strongly retarded than corresponds to a predetermined threshold value, the test braking is interrupted and the braking is continued by pressure action on the further vehicle wheels; corresponding test braking phases are carried out in cyclic sequence for all guidance wheels.

Abstract: A slip control system determines friction/slip characteristics of tires of a road vehicle equipped both with an antilock system to permit an individual brake pressure control on individual vehicle wheels. The front wheel brakes are connected to a primary output pressure space of the tandem master cylinder, and the rear wheel brakes are connected to a secondary output pressure space of the tandem master cylinder. A first bore stage of a housing of the tandem master cylinder forms a housing-defined boundary of the secondary output pressure space. An inner piston flange movably seals off a pressureless downstream chamber in relation to an inner portion of the first bore stage. An intermediate wall of the housing delimits the bore stage relative to a central bore stage which extends from a third bore stage receiving a primary piston.

Abstract: An apparatus and method adapts response slip threshold values for a drive slip and/or a brake slip control system to the tires fitted to a motor vehicle. The drive torque provided at the driven vehicle wheels is determined from measured operating data such as fuel supply and/or combustion air supply, engine speed and total transmission ratio of the drive train of the vehicle. From this determination, the adhesion coefficient .mu..sub.a utilized is determined with a predetermined or measured axle load at the driven vehicle wheels. From the correlation of these adhesion coefficients .mu..sub.a with measured values of the drive slip .lambda..sub.a, the .mu. slip characteristic of the tires is determined and, corresponding thereto, the response slip thresholds .lambda..sub.A and .lambda..sub.B for the drive slip and the antiblocking control are set. A sliding averaging over the quotient .mu..sub.a /.lambda..sub.a of continuously determined .mu.a, .lambda..sub.

Abstract: A vehicle is equipped both with an anti-lock system working on the return-flow principle and with a drive-slip control device working on the differential brake principle, in which the return pump is utilized as an auxiliary pressure source for loading the driven vehicle wheels with brake pressure. In an operational situation requiring drive-slip control, a pump working at a low pressure level is actuated, even before the control responds, and conveys brake fluid both into the brake circuit of the driven vehicle wheel and into the brake circuit of the non-driven vehicle wheels, which are shut off from the brake unit of the brake system by, on one hand, an ASR-function control valve and, on the other hand, by an isolating valve. The pre-charge pump of the return pump of the brake circuits of the driven vehicle wheels is used as a low-pressure pump.