Fault diagnostic device and method

• US 6,195,763 B1
• Filed: 06/01/1998
• Issued: 02/27/2001
• Est. Priority Date: 06/02/1997
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Wolf, Jürgen, Dambach, Dieter-Andreas, Mallebrein, Georg, Hillner, Hans, Mayer, Rudi, Bellmann, Holger, Frank, Rainer, Schiemann, Juergen, Menrad, Gudrun
• Primary Examiner(s): Iqbal, Nadeem
• Application Number:
  US09/088,612
• Time in Patent Office: 1,002 Days
• Field of Search: 714/25, 714/2, 714/8, 714/15, 714/16, 714/21, 714/27, 714/32, 714/37, 714/39, 714/44, 714/47-49, 714/742, 714/747, 714/764, 364/550, 364/264, 364/267, 364/424.03, 364/551.01, 364/554
• US Class Current: 714/25
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A fault diagnostic device for monitoring and detecting faults in technical functions, in particular in technical functions of a motor vehicle, includes a plurality of monitoring devices for monitoring technical functions, whether they have a fault or not. The fault diagnostic device also includes a storage device for storing (data concerning) direct mutual dependencies of the functions to be monitored, in the form of a matrix representation in the logical YES/NO form. Furthermore, the fault diagnostic device includes a processing device for determining the capacity for validation of faults in corresponding technical functions to be detected in the monitoring, in view of the matrix representation; for controlling the monitoring devices for carrying out the monitoring activities; and, assuming the capacity for validation, for validating the faults to be detected in the monitoring.

Claims

1. A fault diagnostic device for monitoring and detecting faults in technical functions of an apparatus, comprising:

monitoring devices monitoring the technical functions and determining one of a fault condition and a no fault condition;

a storage device storing data corresponding to direct mutual dependencies of the technical functions being monitored, the data being stored as a matrix in a logical YES/NO form; and

a processing device;

a) determining a validation capacity of the faults to be detected in the technical functions using the matrix,

b) controlling the monitoring devices, and

c) validating the faults, if the validation capacity is sufficient.

2. The device according to claim 1, wherein the apparatus is a motor vehicle.

3. The device according to claim 1, wherein the processing device detects a direct deadlock if the matrix of each of two of the technical functions includes a corresponding YES entry being symmetrical to a main diagonal of the matrix.

4. The device according to claim 1, wherein the processing device:

forms all of reduced matrices of the direct mutual dependencies without forming a maximum of three of the reduced matrices if at least three of the technical functions are present,

determines if one of the reduced matrices includes one of a linearly independent logical line-unit vector and a linearly independent logical column-unit vector, and

detects an indirect deadlock if one of the reduced matrices includes one of the linearly independent logical line-unit vector and the linearly independent logical column-unit vector.

5. The device according to claim 4, wherein the processing device calculates a determinant of the reduced matrices.

6. The device according to claim 3, wherein the processing device:

d) determines if at least one function of the technical functions is dependent only on a deadlock operation corresponding to the direct deadlock, the at least one function depending on further functions, the further functions having no faults and no additional functions, and

e) if the at least one function can be determined, resolves the direct deadlock corresponding to the at least one function and validates the fault condition of the technical functions detected as faulty corresponding to the direct deadlock.

7. The device according to claim 4, wherein the processing device:

d) determines if at least one function of the technical functions is dependent only on a deadlock operation corresponding to a further deadlock, the further deadlock being one of the direct deadlock and the indirect deadlock, the at least one operation depending on further functions, the further functions having no faults and no additional functions, and

e) if the at least one function can be determined, resolves the further deadlock corresponding to the at least one function and validates the fault condition of the technical functions detected as faulty corresponding to the further deadlock.

8. A method for monitoring and detecting faults of technical functions of an apparatus, comprising the steps of:

determining the technical functions to be monitored;

providing direct mutual dependencies of the technical functions as a matrix in a logical YES/NO form;

determining a validation capacity of the faults using the matrix;

controlling monitoring devices, the monitoring devices monitoring the technical functions; and

if the validation capacity is sufficient, validating the faults.

9. The method according to claim 8, wherein the apparatus is a motor vehicle.

10. The method according to claim 8, further comprising the step of:

detecting a direct deadlock if the matrix of each of two of the technical functions includes a corresponding YES entry being symmetrical to a main diagonal of the matrix.

11. The method according to claim 8, further comprising the steps of:

forming all of reduced matrices of the direct mutual dependencies without forming a maximum of three of the reduced matrices if at least three of the technical functions are present,

determining if one of the reduced matrices includes one of a linearly independent logical line-unit vector and a linearly independent logical column-unit vector, and

detecting an indirect deadlock if one of the reduced matrices includes one of the linearly independent logical line-unit vector and the linearly independent logical column-unit vector.

12. The method according to claim 11, further comprising the step of:

determining a determinant of the reduced matrices.

13. The method according to claim 10, further comprising the steps of:

determining if at least one function of the technical functions is dependent only on a deadlock operation corresponding to a further deadlock, the further deadlock being one of the direct deadlock and the indirect deadlock, the at least one function depending on further functions, the further functions having no faults and no additional functions, and

if the at least one function can be determined, resolving the further deadlock corresponding to the at least one function and validating the fault condition of the technical functions detected as faulty corresponding to the further deadlock.

14. The method according to claim 11, further comprising the steps of:

determining if at least one function of the technical functions is dependent only on a deadlock operation corresponding to a further deadlock, the further deadlock being one of the direct deadlock and the indirect deadlock, the at least one function depending on further functions, the further functions having no faults and no additional functions, and

if the at least one function can be determined, resolving the further deadlock corresponding to the at least one function and validating the fault condition of the technical functions detected as faulty corresponding to the further deadlock.