Fault-tolerant vehicle stability control

• US 20040162650A1
• Filed: 02/19/2003
• Published: 08/19/2004
• Est. Priority Date: 02/19/2003
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Kueperkoch, Stefan, Kojic, Aleksandar, Grimm, Wolfgang, Ahmed, Jasim, Hathout, Jean-Pierre, Martin, Christopher
• Granted Patent: US 7,245,995 B2
• Time in Patent Office: Days
• US Class Current: 701/29
• CPC Class Codes: B60G 17/0185 for failure detection
• CPC Class Codes: B60T 2270/402 Back-up
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02
• CPC Class Codes: B60T 8/885 using electrical circuitry

Abstract

A system and method for providing a fault tolerant vehicle dynamics control (VDC) is described. The system includes a fault tolerance module that receives an indication of a fault in at least one of the actuators of the VDC and selects a fault compensation mode to maintain the stability of the motor vehicle in light of the received fault indication. The fault tolerance module proceeds by diagnosing at least one fault in at least one of the actuators, selecting a fault compensation mode based on the detected at least one fault and the driving condition, and compensating for the at least one fault by optimally controlling remaining operable actuators according to the fault compensation mode.

Claims

1. A fault tolerant VDC system for a motor vehicle comprising:

VDC actuators; and

a fault tolerance module configured to receive an indication of a fault in at least one of the VDC actuators to select a fault compensation mode to maintain the stability of the motor vehicle in light of the received fault indication.

2. The fault tolerant VDC system of claim 1, further comprising:

an extended VDC controller, the extended VDC controller storing algorithms corresponding to fault compensation modes and controlling remaining operable VDC actuators based on the fault compensation mode algorithm selected by the fault tolerance module.

3. The fault tolerant VDC system of claim 2, further comprising:

self-diagnostic actuator sensors allocated to each of the VDC actuators operable to detect a fault in the VDC actuators, each self-diagnostic actuator sensor providing a fault indication to the fault tolerance module when a fault is detected.

4. The fault tolerant VDC system of claim 2, further comprising:

at least one sensor for detecting at least one vehicle dynamics parameter of the motor vehicle; and

a fault isolation module, the fault isolation module;

a) receiving vehicle dynamics information from the sensors and driver input command information;

b) determining from the at least one vehicle dynamics parameter and driver input command information whether fault symptoms exist at the VDC actuators;

c) diagnosing which of the VDC actuators are faulty; and

d) sending an indication of which VDC actuators are faulty to the fault tolerance module.

5. The fault tolerant VDC system of claim 4, wherein the fault isolation module includes a model-based fault detection module and a signal-based fault detection module.

6. The fault tolerant VDC system of claim 5, wherein the signal-based fault detection module performs at least one of threshold checks, range plausibility checks and vibration signal-model based checks with respect to a detected vehicle dynamics parameter to detect a fault symptom.

7. The fault tolerant VDC system of claim 5, wherein the model-based fault detection module employs at least one of parameter estimation techniques, state estimation techniques and parity equations to detect a fault symptom.

8. The fault tolerant VDC system of claim 4, further comprising:

electric motor wheel accelerators activatable by the extended VDC controller during execution of a selected fault compensation mode.

9. A method of providing fault tolerance for a VDC system that controls a plurality of actuators to maintain the stability of a motor vehicle during a challenging driving condition, the method comprising:

diagnosing at least one fault in at least one of the actuators;

selecting a fault compensation mode based on the detected at least one fault and the driving condition; and

compensating for the at least one fault by controlling remaining operable actuators according to the fault compensation mode.

10. The method of claim 9, further comprising:

employing a rules-based decision making process for selecting the fault compensation mode.

11. The method of claim 10, further comprising:

performing a static tree analysis for selecting the fault compensation mode.

12. The method of claim 10, further comprising:

employing the rules-based decision making process to diagnose the at least one fault.

13. The method of claim 12, further comprising:

generating a static fault tree to provide the rules-based decision making process.

14. The method of claim 9, further comprising:

directly measuring vehicle dynamics parameters;

computing further vehicle dynamics parameters; and

detecting fault symptoms based on the directly measured and the further vehicle dynamics parameters.

15. The method of claim 14, wherein the fault symptoms are detected using a signal-based fault detection technique.

16. The method of claim 14, wherein the fault symptoms are detected using a model-based fault detection technique.

17. The method of claim 14, wherein the fault symptoms are detected using both a signal-based fault detection technique and a model-based fault detection technique.

18. The method of claim 9, wherein the at least one actuator includes at least one of wheel brake actuators, an active steering actuator, and electric motor wheel accelerators.

19. The method of claim 9, further comprising:

optimizing an already-implemented control strategy for compensating at least one actuator fault in real time based on the at least on diagnosed fault and driving condition.