The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 04, 1993
Filed:
Jul. 08, 1991
Volker Berkefeld, Renningen, DE;
Dr. Ing. h.c.F. Porsche AG, , DE;
Abstract
An active four-wheel steering system for motor vehicles has steering devices for the front wheels and the rear wheels. These devices operate as a function of driving condition quantities fed to an electronic control unit. A variable wheel steering angle relationship with respect to the front wheels is adjusted, in which case the input signal concerning the steering wheel angle from a steering wheel angle sensor and the additional signal concerning the vehicle speed from a speed sensor is fed to a first function calculation task apparatus of the control unit. This function calculation task apparatus generates a first output signal for the lateral acceleration which, as an input signal, together with the additional input signal of the vehicle speed, is fed to a second function calculation task apparatus. In order to take a driving speed change into account, the output signal concerning the lateral acceleration, together with a signal from the driving speed change, is fed to the third function calculation task apparatus. This input signal, computed in the first function calculation task apparatus, and the input signals concerning the speed change, computed in the third function calculation task apparatus, are converted to an output signal additional rear wheel steering angle, which is overlayed on the output signal rear wheel steering angle. The sum of these output signals, as the steering angle signal, are fed to the control unit for the control of the hydraulic steering device for the rear wheels.