Technique for Redundant Registration of an Actuation of a Motor-Vehicle Braking System

Abstract

A technique is described for the redundant registering of an actuation of a motor-vehicle brake system. A device which is provided for this purpose comprises a first sensor for generating a first sensor signal which indicates a movement of a mechanical input component of the brake system, and a second sensor for generating a second sensor signal which indicates a hydraulic pressure in the brake system. A processing device which is coupled to the two sensors is configured for selectively outputting an actuation signal which is generated on the basis of the first sensor signal or an actuation signal which is generated on the basis of the second sensor signal. The actuation signal indicates an actuation of the brake system.

1 . An apparatus for redundant registering of an actuation of a motor-vehicle braking system, comprising:
 at least one first sensor for generating a first sensor signal, the first sensor signal indicating a movement of a mechanical input component of the braking system;   at least one second sensor for generating a second sensor signal, the second sensor signal indicating a hydraulic pressure in the braking system;   a processing device coupled with the at least one first sensor and with the at least one second sensor, which is designed:
 to selectively output an actuation signal generated on the basis of the first sensor signal or an actuation signal generated on the basis of the second sensor signal, the actuation signal indicating an actuation of the braking system; and, 
 to output the actuation signal generated on the basis of the first sensor signal in a case of normal operational capability of the apparatus, and/or to output the actuation signal generated on the basis of the second sensor signal in a case of irregular operational capability of the apparatus. 
   
     
     
         2 . The apparatus according to  claim 1 , wherein the processing device is designed to draw upon the second sensor signal or a signal derived therefrom for the purpose of checking a plausibility of the first sensor signal. 
     
     
         3 . The apparatus according to  claim 2 , wherein the processing device is designed to infer an irregular operational capability of the apparatus in the case of a negative plausibility check of the first sensor signal. 
     
     
         4 . The apparatus according to  claim 1 , wherein the processing device includes the following:
 a first evaluating unit coupled with at least the at least one first sensor, which is designed for evaluating the first sensor signal and for generating the actuation signal on the basis of the first sensor signal; and/or   a second evaluating unit coupled with at least the at least one second sensor, which is designed for evaluating the second sensor signal and for generating the actuation signal on the basis of the second sensor signal.   
     
     
         5 . The apparatus according to  claim 4 , wherein the first evaluating unit is different from the second evaluating unit and is arranged parallel to the latter. 
     
     
         6 . The apparatus according to  claim 4 , wherein the processing device ( 12 ) further includes a checking unit coupled with at least the first evaluating unit, which is designed for checking the operational capability of at least the first evaluating unit, whereby in the case of irregular operational capability of the first evaluating unit the actuation signal generated on the basis of the second sensor signal is to be output. 
     
     
         7 . The apparatus according to  claim 6 , wherein the processing device further includes a multiplexer coupled with output sides of the first evaluating unit and of the second evaluating unit, which is capable of being driven by the checking unit as a function of the operational capability of at least the first evaluating unit, in order to selectively output the actuation signal generated on the basis of the first sensor signal or the actuation signal generated on the basis of the second sensor signal. 
     
     
         8 . The apparatus according to one of  claim 4 , wherein the second evaluating unit includes a comparator which is designed to compare the second sensor signal with a reference signal and to generate the actuation signal as a function of the comparison. 
     
     
         9 . The apparatus according to  claim 1 , wherein the at least one first sensor is designed for registering an actuation of a brake pedal. 
     
     
         10 . The apparatus according to  claim 9 , wherein the at least one first sensor has been selected from the following group of sensors: pedal-travel sensor, pedal-angle sensor, pedal-force sensor and brake-light switch. 
     
     
         11 . The apparatus according to  claim 1 , wherein the at least one second sensor is a hydraulic-pressure sensor. 
     
     
         12 . The apparatus according to  claim 11 , wherein the hydraulic-pressure sensor has been assigned to a wheel-slip control system. 
     
     
         13 . A method for redundant registering of an actuation of a motor-vehicle braking system, comprising:
 providing at least one first sensor for generating a first sensor signal, the first sensor signal indicating a movement of a mechanical input component of the braking system;   providing at least one second sensor for generating a second sensor signal, the second sensor signal indicating a hydraulic pressure in the braking system;   selectively outputting an actuation signal generated on the basis of the first sensor signal, or an actuation signal generated on the basis of the second sensor signal, which indicates an actuation of the braking system;   in a case of normal operational capability of an extended braking system including the braking system, outputting the actuation signal generated on the basis of the first sensor signal, and/or in a case of irregular operational capability of the extended braking system, outputting the actuation signal generated on the basis of the second sensor signal.   
     
     
         14 . The method according to  claim 13 , wherein the second sensor signal or a signal derived therefrom is drawn upon for the purpose of checking a plausibility of the first sensor signal. 
     
     
         15 . The method according to  claim 14 , wherein in the case of a negative plausibility check of the first sensor signal an irregular operational capability of the apparatus is inferred. 
     
     
         16 . The method according to one of  claim 13 , wherein
 a first evaluating unit coupled with at least the at least one first sensor evaluates the first sensor signal and generates the actuation signal on the basis of the first sensor signal; and/or   a second evaluating unit coupled with at least the at least one second sensor evaluates the second sensor signal and generates the actuation signal on the basis of the second sensor signal.   
     
     
         17 . The method according to  claim 16 , wherein in the case of irregular operational capability of the first evaluating unit the actuation signal generated on the basis of the second sensor signal is output. 
     
     
         18 . A computer-program product with program-code means for implementing the steps of  claim 13  when the computer-program product is run on a computer device.