Robert Boschgmbh

Lucas Industries Public Limited Company

Lucas Industries Limited

Lucas Automotive Gmbh

Volker Braschel

Dieter Seitz

Heinz Leiber

Wolf-Dieter Jonner

Dieter Roller

Reiner Emig

Hubert E Schmitt

Josef Pickenhahn

Jochen Schafer

Dieter Voges

Herbert Demel

Jurgen Gerstenmeier

Wolfgang Kampfmann

Hans-Herbert Wupper

Michael Mendel

In order to improve an electronic system for a motor vehicle which comprises an electronic controller which is coupled via an electronic communication system to electronic controllers of other electronic systems of the vehicle in order to co-operate through data exchanges with the other electronic systems of the vehicle, wherein electronic sensor devices for controlling and/or regulating operating states of the vehicle detect quantities which are related to the operating states of the vehicle, so as to obtain cost and functional advantages, it is proposed that at least one of the electronic sensor devices be accommodated in one of the electronic controllers.

Electronic system for a motor vehicle

A method of controlling the brake pressure in an anti-lock brake system of a dual-track vehicle wherein pressure raising pulse trains are applied to the brakes of the rear wheels of the vehicle provides for modified 'select-low' control of a kind with which the brake of the one wheel which first is instable on the rear axle is fed with a pressure raising pulse train having a smaller mark-to-space ratio or pulse duty factor than the pressure raising pulse train applied to the brake of the other, the stable wheel of the rear axle.

Method for controlling the brake pressure in an anti-lock brake system

A method of controlling the brake pressure in an anti-lock vehicle brake system provides for short distances to stop to be reached even with greatly differing mass moments of inertia by calculating the pressure reduction period of a control cycle currently under way as the product of a first factor and a second factor. The first factor depends on the pressure reduction period in the preceding control cycle, and the second factor depends on the maximum re-acceleration of the wheel in the preceding control cycle.

Method of controlling the brake pressure in an anti-lock vehicle brake

In a method of controlling the brake pressure of a vehicle brake system equipped with anti-lock protection it is provided to measure the slip and/or rotational retardation of a wheel whose brake is applied and to compare each measured value with a given threshold value so as to lower the brake pressure if the threshold value proves to have been surpassed. Undesired pressure reductions can be avoided by increasing the threshold value for given periods of time from a basic value (S.sub.G) and subsequently decreasing it again. At a point in time T.sub.1 at which the rotational retardation of the braked wheel is greater than a value corresponding to a physically feasible slowdown of the vehicle the threshold value is increased abruptly, to be decreased thereafter according to a predetermined function of time. During the lowering of the threshold value the change in speed of the retarded wheel is measured over given intervals of time .DELTA.T and compared with the instantaneous higher threshold value. If the comparison demonstrates that the change in speed in question is greater than the instantaneous raise in threshold value, the threshold value is reduced to the basic value (S.sub. G).

Control of ABS threshold without accompanying reduction of brake pressure

Automatic anti-skid brake control system

In a method of controlling the brake pressure in the rear wheel brakes of a double-track vehicle, wherein the rotational speeds at least of the rear wheels are measured and the brake pressure is lowered, kept constant, or raised, depending on the unstable or stable states arising at the individual rear wheels, the pressure in the brake of a stable rear wheel being approximated at least temporarily to the pressure in the brake of an unstable rear wheel, it is provided that, upon initiating a pressure decrease in the brake of an unstable rear wheel, the pressure in the brake of the stable rear wheel is kept constant for a predetermined period of time (.DELTA.t) and then decreased until the pressure in the brake of the unstable wheel is either kept constant or increased. This guarantees shorter stopping distances and at the same time provides a smaller difference in the braking torques at the rear axle, at good stability of the motor vehicle.

Method of controlling the brake pressure in the rear wheel brakes of a

For measuring the rotational speed of a wheel in an antilocking protected vehicle brake system a rotational speed sensor is provided in which in accordance with the rotational speed of the wheel signals are electromagnetically induced which have an amplitude and frequency which increase regularly with the rotational speed. When due to error sources the amplitude of the induced signal does not increase with the frequency of the signal a rotational speed measured value is determined by means of the measured amplitude, i.e. not on the basis of the measured frequency. To avoid erroneous measuring signals it may likewise be provided that when the amplitude of the signal does not increase with its frequency the last measured value of the frequency of the induced signal at which the amplitude still increased with the frequency is used to determine the speed of rotation.

Method of examining functionability of a wheel speed sensor

Method for measuring the rotational speed of a wheel in an

Method of controlling the brake pressure in an antilock vehicle brake

A method of controlling the brake pressure in an anti-lock vehicle braking system provides for determining the deviation of a control magnitude, such as the slip or retardation of a wheel, from a given rated value Sw in the course of a control cycle. A threshold value which is decisive for the pressure decrease at a wheel subject to the risk of becoming locked is changed for the next successive control cycle in response to the amount of the deviation of the control magnitude from the rated value.

Brake pressure control method

Anti-lock braking system

In an anti-lock vehicle braking system the brake pressure acting at the controlled wheel is controlled in such a manner that the threshold value with respect to the rotational retardation of the wheel at the beginning of a lowering or raising of pressure is increased briefly, during a control cycle, by a constant amount (S.sub.H -S.sub.G) with respect to a threshold base value (S.sub.G) in order to avoid any undesired control operations caused especially by axle vibrations, pot holes, and the like. The threshold value is then decreased in response to the period of time of the pressure reduction in the preceding control cycle. The decreasing of the threshold value is carried on to values S.sub.T below the threshold base value and maintained for a given time interval (t.sub.x -t.sub.y).

Anti-locking brake control system

A method of controlling the brake pressure in an antilock (ABS) vehicle brake system provides for adapting the wheel at which the brake is applied to the optimum course of the coefficient of friction/slip curve by determining the rotational retardation of the braked wheel, upon initiation of a braking action, after given time intervals each and comparing it with the rotational retardation of the preceding time interval. Moreover, the brake pressure is varied in response to the result of the comparison. The renewed acceleration of the retarded wheel also is monitored accordingly so as to effect further lowering of the brake pressure if the renewed acceleration or the gain in acceleration is too small.

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Neuwied, Germany

Volker Braschel