Method and device for monitoring sensors in a vehicle

• US 6,223,107 B1
• Filed: 05/26/1999
• Issued: 04/24/2001
• Est. Priority Date: 07/02/1997
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Urban, Werner, Mergenthaler, Rolf-Hermann
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US09/254,250
• Time in Patent Office: 699 Days
• Field of Search: 701/34, 701/41, 701/72, 701/75, 701/78, 701/80, 701/83, 701/74, 303/146, 303/147, 303/149, 303/148
• US Class Current: 701/34
• CPC Class Codes: B60T 2250/06 Sensor zero-point adjustment; Offset compensation
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: G01D 18/004 Continuous recalibration
• CPC Class Codes: G01D 3/08 with provision for safeguarding the apparatus, e.g. against abnormal operation, against breakdown
• CPC Class Codes: G01P 21/02 of speedometers

Abstract

A device to monitor sensors in a motor vehicle, with the sensors generating signals, each representing different physical is provided. The device includes first arrangement with which identically defined comparison variables for the sensors are determined for at least two sensors on the basis of at least the signals generated by them. Furthermore, the device includes a second arrangement with which a reference variable is determined on the basis of at least two of the identically defined comparison variables and is taken into account in monitoring performed in a third arrangement for at least one sensor. To form the reference variable, a variable describing the difference between the identically defined comparison variable and the other identically defined comparison variables of the minimum of two identically defined comparison variables is determined for each of the minimum of two identically defined comparison variables. The identically defined comparison variable is evaluated using this variable.

Claims

1. A device for monitoring a least one of a plurality of sensors in a motor vehicle, the sensors generating signals, each of the signals representing a different physical variable, comprising:

a first arrangement determining identically defined comparison variables for at least two of the sensors as a function of the signals generated by the at least two of the sensors;

a second arrangement determining a reference variable as a function of at least two of the identically defined comparison variables, the reference variable being determined as a function of a variable describing a difference between each one of the at least two of the identically defined comparison variables and the others of the at least two of the identically defined comparison variables, the one of the at least two of the identically defined comparison variables being weighted by the variable describing the difference; and

a third arrangement monitoring the at least one of the sensors as function of the reference variable.

2. The device according to claim 1, wherein the identically defined comparison variables represent a physical variable, the physical variable corresponding to a yaw rate detected by one of the sensors.

3. The device according to claim 1, wherein a vehicle speed variable representing vehicle speed is determined as a function of the signals generated by the sensors, a sensor reference variable being determined for the at least one of the sensors as a function of the vehicle speed variable, the sensor reference variable being used to monitor the at least one of the sensors.

4. The device according to claim 3, wherein the signals generated by the at least one of the sensors is corrected as a function of the sensor reference variable and the signals generated.

5. The device according to claim 1, wherein the sensors include wheel rpm sensors, one of a rotational rate sensor and yaw rate sensor, a transverse acceleration sensor, and a steering angle sensor.

6. The device according to claim 1, wherein a vehicle speed variable representing vehicle speed is determined as a function of the signals generated by the sensors, a sensor reference variable being determined for the at least one of the sensors as a function of the vehicle speed variable and the reference variable, the sensor reference variable being used to monitor the at least one of the sensors.

7. A device for monitoring a least one of a plurality of sensors in a motor vehicle, the sensors generating signals, each of the signals representing a different physical variable, comprising:

a first arrangement determining identically defined comparison variables for at least two of the sensors as a function of the signals generated by the at least two of the sensors;

a second arrangement determining a reference variable as a function of at least two of the identically defined comparison variables, the reference variable being determined as a function of a variable describing a difference between each one of the at least two of the identically defined comparison variables and the others of the at least two of the identically defined comparison variables, the one of the at least two of the identically defined comparison variables being weighted by the variable describing the difference; and

a third arrangement monitoring the at least one of the sensors as function of the reference variable, wherein;

a first one of the identically defined comparison variables is omeganij and is determined for wheel rpm sensors as a function of a variable representing vehicle speed and the signals generated by the wheel rpm sensors;

a second one of the identically defined comparison variables is omegakorr and is determined for one of a rotational rate sensor and a yaw rate sensor as a function of at least the signals generated by the one of the rotational rate sensor and the yaw rate sensor, and a sensor reference variable for the one of the rotational rate sensor and the yaw rate sensor;

a third one of the identically defined comparison variables is omegaay and is determined for a transverse acceleration sensor as a function of at least the signals generated by the transverse acceleration sensor, the variable representing vehicle speed, and a sensor reference variable for the transverse acceleration sensor;

a fourth one of the identically defined comparison variables is omegadelta and is determined for a steering angle sensor as a function of at least the signals generated by the steering angle sensor, the variable representing vehicle speed, and a sensor reference variable for the steering angle sensor; and

the reference variable is determined according to the equation;

$<br><br>\mathrm{omegaref}=\frac{\begin{array}{c}\frac{\mathrm{omegakorr}}{\mathrm{D12}·<br><br>\mathrm{D13}·<br><br>\mathrm{D14}}+\frac{\mathrm{omegadelta}}{\mathrm{D12}·<br><br>\mathrm{D23}·<br><br>\mathrm{D24}}+\\ \frac{\mathrm{omeganij}}{\mathrm{D13}·<br><br>\mathrm{D23}·<br><br>\mathrm{D34}}+\frac{\mathrm{omegaay}}{\mathrm{D14}·<br><br>\mathrm{D24}·<br><br>\mathrm{D34}}\end{array}}{\begin{array}{c}\frac{1}{\mathrm{D12}·<br><br>\mathrm{D13}·<br><br>\mathrm{D14}}+\frac{1}{\mathrm{D12}·<br><br>\mathrm{D23}·<br><br>\mathrm{D24}}+\\ \frac{1}{\mathrm{D13}·<br><br>\mathrm{D23}·<br><br>\mathrm{D34}}+\frac{1}{\mathrm{D14}·<br><br>\mathrm{D24}·<br><br>\mathrm{D34}}\end{array}}$

where the terms;

D12=|omegakorr−

omegadelta|, D13=|omegakoor=omeganij|, D14=|omegakoor−

omegaay|, D23=|omegadelta−

omeganij|, D24=|omegadelta−

omegaay| and D34=|omeganij−

omegaay|

describe the difference between each of the at least two identically defined comparison variables and the others of the at least two identically defined comparison variables.

8. A method of monitoring sensors in a vehicle, comprising the steps of:

generating signals via the sensors, each of the signals representing different physical variables;

determining identically defined comparison variables for at least two of the sensors as a function of the signals generated by the at least two of the sensors;

determining a reference variable as a function of at least two of the identically defined comparison variables, the reference variable being determined as a function of a difference between each of the at least two identically defined comparison variable and the others of the at least two identically defined comparison variables; and

monitoring at least one of the sensors using the reference variable.