TRANSMISSION CONTROL MODULE

• US 20100204879A1
• Filed: 02/12/2010
• Published: 08/12/2010
• Est. Priority Date: 02/12/2009
• Status: Active Grant

• Current Assignee: Eaton Cummins Automated Transmission Technologies, LLC
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Brown, Kim A., Stasik, Anthony, Hawarden, Jeffrey P., Connolly, Thomas R., Katrak, Kerfegar K., McKenzie, Ian D., Fritz, Todd W.
• Granted Patent: US 8,412,425 B2
• Time in Patent Office: Days
• US Class Current: 701/34
• CPC Class Codes: F16H 2061/1208 with diagnostic check cycles; Monitoring of failures
• CPC Class Codes: F16H 2061/122 Avoiding failures by using redundant parts
• CPC Class Codes: F16H 2061/1268 Electric parts of the controller, e.g. a defect solenoid, wiring or microprocessor
• CPC Class Codes: F16H 2061/1284 the failing part is a sensor
• CPC Class Codes: F16H 61/12 Detecting malfunction or potential malfunction, e.g. fail safe in control of hydrostatic gearing F16H61/4192; Circumventing or fixing failures

Abstract

An exemplary transmission system includes a plurality of sensors each configured to output a signal at least partially representative of a speed of at least one of a first transmission input shaft, a second transmission input shaft, a transmission output shaft, and an engine. A transmission control module is in communication with the plurality of sensors and is configured to identify at least one of the plurality of sensors as a failed sensor and another of the plurality of sensors as a working sensor. The transmission control module is further configured to estimate the signal of the failed sensor based on a predetermined relationship between an expected signal from the failed sensor and the signal received from the working sensor.

Claims

1. A system comprising:

a plurality of sensors each configured to output a signal at least partially representative of a speed of at least one of a first transmission input shaft, a second transmission input shaft, a transmission output shaft, and an engine; and

a transmission control module in communication with the plurality of sensors and configured to identify at least one of the plurality of sensors as a failed sensor and another of the plurality of sensors as a working sensor, wherein the transmission control module is configured to estimate the signal of the failed sensor based on a predetermined relationship between an expected signal from the failed sensor and the signal received from the working sensor.

2. A system as set forth in claim 1, wherein the transmission control module is configured to identify at least one of the plurality of sensors as the failed sensor by comparing each of the signals received from each of the plurality of sensors to the expected signal that corresponds to each of the signals received.

3. A system as set forth in claim 1, wherein the predetermined relationship is a function of at least one of a clutch engage fraction and a gear selection.

4. A system as set forth in claim 1, wherein the transmission control module is configured to independently process signals from the plurality of sensors along a primary processing path and a secondary processing path.

5. A system as set forth in claim 4, wherein the transmission control module is configured to determine whether the primary processing path has failed by comparing at least one of the signals processed along the primary processing path with at least one of the signals processed along the secondary processing path.

6. A system as set forth in claim 4, wherein the transmission control module includes a primary filter in communication with the plurality of sensors and a secondary filter in communication with the plurality of sensors.

7. A system as set forth in claim 6, wherein at least one of the primary filter and the secondary filter includes a band-pass filter.

8. A system as set forth in claim 4, wherein the transmission control module includes at least one filter and at least one conditioning circuit in communication with the plurality of sensors and along each of the primary processing path and the secondary processing path.

9. A system as set forth in claim 8, wherein the at least one filter includes a band-pass filter and wherein the conditioning circuit includes a current mirror circuit.

10. A system as set forth in claim 1, wherein the transmission control module includes a conditioning circuit in communication with the plurality of sensors.

11. A system as set forth in claim 10, wherein the conditioning circuit includes a current mirror circuit.

12. A vehicle comprising:

a plurality of sensors each configured to output a signal at least partially representative of a speed of at least one of a first transmission input shaft, a second transmission input shaft, a transmission output shaft, and an engine; and

a transmission control module in communication with the plurality of sensors and configured to identify at least one of the plurality of sensors as a failed sensor and another of the plurality of sensors as a working sensor, wherein the transmission control module is configured to estimate the signal of the failed sensor based on a predetermined relationship between an expected signal from the failed sensor and the signal received from the working sensor,

wherein the transmission control module is configured to independently process signals from the plurality of sensors along a primary processing path and a secondary processing path, wherein the transmission control module is configured to determine whether the primary processing path has failed by comparing at least one of the signals processed along the primary processing path to at least one of the signals processed along the secondary processing path.

13. A vehicle as set forth in claim 12, wherein the transmission control module is configured to identify at least one of the plurality of sensors as the failed sensor by comparing each of the signals received from each of the plurality of sensors to the expected signal that corresponds to each of the signals received.

14. A vehicle as set forth in claim 12, wherein the predetermined relationship is a function of at least one of a clutch engage fraction and a gear selection.

15. A vehicle as set forth in claim 12, wherein the transmission control module includes a conditioning circuit in communication with the plurality of sensors, the conditioning circuit including a current mirror circuit.

16. A vehicle as set forth in claim 12, wherein the transmission control module includes a primary filter in communication with the plurality of sensors and a secondary filter in communication with the plurality of sensors, wherein at least one of the primary filter and the secondary filter includes at least one of a band-pass filter, a high-pass filter, and a low-pass filter.

17. A method comprising:

measuring a speed of at least one of a first transmission input shaft, a second transmission input shaft, a transmission output shaft, and an engine with at least one of a plurality of sensors;

generating a signal representative of each of the speeds measured;

receiving each of the signals at a transmission control module;

identifying, at the transmission control module, at least one of the plurality of sensors as a failed sensor and at least one of the plurality of sensors as a working sensor;

estimating, at the transmission control module, the signal of the failed sensor based on a predetermined relationship between an expected signal from the failed sensor and the signal received from the working sensor.

18. A method as set forth in claim 17, wherein the transmission control module is configured to process the signals from the plurality of sensors along a primary processing path and a secondary processing path, and further comprising determining whether the primary processing path has failed.

19. A method as set forth in claim 18, wherein determining whether the primary processing path has failed includes comparing at least one of the signals processed along the primary processing path to at least one of the signals processed along the secondary processing path.

20. A method as set forth in claim 17, wherein identifying the at least one of the plurality of sensors as the failed sensor includes comparing the signals received from each of the plurality of sensors to an expected signal that corresponds to each of the signals received.