Traction control system for 4WD/AWD vehicles equipped with onboard camera

Patent metadata

Field	Value
Publication number	US-9481243-B2
Application number	US-201414331365-A
Country	US
Kind code	B2
Filing date	Jul 15, 2014
Priority date	Jul 15, 2013
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A method controls a powertrain that directs power from an engine and a transmission to all four wheels or to just front wheels or to just rear wheels. The method includes monitoring information transmitted over a communications network. The method determines whether one or more components of the powertrain are in an active condition or in an inactive condition. The one or more components of the powertrain are in the inactive condition when not connected to the transmission and not connected to the front wheels or the rear wheels. The one or more components of the powertrain are in the active condition when connected to the transmission and connected to the front wheels and the rear wheels. The method switches the one or more components of the powertrain between the inactive condition and the active condition based at least in part on visual data provided by an on-board camera system.

First claim

What is claimed is:

1. A vehicle drivetrain for transferring torque from a powertrain to a first and second sets of wheels, the drivetrain comprising:
a first driveline being adapted to transfer torque to the first set of wheels and including a first power disconnection device for adjusting the amount of torque transferred to at least one of the sets of wheels;
a second driveline being adapted to transfer torque to the second set of wheels and including a second power disconnection device for adjusting the amount of torque transferred to at least one of the sets of wheels;
a camera system including at least one camera mounted to the vehicle for acquiring visual data;
a road analysis module electrically connected with said camera system and configured to receive the acquired visual data from said camera and to calculate a coefficient of friction between tires of the vehicle and a road surface based on said processed visual data; and
a controller electrically connected with said first and second power disconnection devices and said road analysis module and configured to control actuation of said first and second power disconnection devices based on said coefficient of friction determined by said road analysis module;
wherein said camera is further configured to transmit visual data to a vehicle control system that is separate from said road analysis module.

2. The drivetrain as set forth in claim 1 wherein said camera system further includes an image processing unit for processing said visual data acquired by said camera and sending said processed visual data to said road analysis module.

3. The drivetrain as set forth in claim 2 further including at least one sensor mounted on the vehicle for measuring at least one driving characteristic of the vehicle, and said at least one sensor electrically connected with said controller to further control said actuation of said first and second power disconnection devices based on said driving characteristic measured by said sensor.

4. The drivetrain as set forth in claim 3 wherein said driving characteristic measured by said sensor is at least one of drive mode status and wheel slip.

5. The drivetrain as set forth in claim 1 further including a power take-off unit for transmitting drive torque from the powertrain, said second driveline further including a rear axle assembly having a first rear axleshaft and a second rear axleshaft each connected to a wheel of the second set of wheels, said second driveline further including a propeller shaft interconnecting said power takeoff unit and said rear axle assembly for transmitting torque from said power take-off unit to said rear axle assembly to provide rotary movement to said second set of wheels.

6. The drivetrain as set forth in claim 5 wherein said first power disconnection device is adjustably connected to said propeller shaft of said second driveline for drivingly connecting and disconnecting said propeller shaft of said second driveline from the power take-off unit.

7. The drivetrain as set forth in claim 1 further including a vehicle readiness system configured to determine at least one of a sudden direction change and air bag deployment, and wherein said vehicle readiness system is electrically connected with said controller such that said controller further controls said actuation of said first and second power disconnection devices based on said sudden direction change or said air bag deployment of the vehicle determined by said vehicle readiness system.

8. The drivetrain as set forth in claim 1 further including a driver information center electrically connected with said controller, and wherein said controller further controls said actuation of said first and second power disconnection devices based on attributes of the vehicle determined by said driver information system.

9. The drivetrain as set forth in claim 1 wherein the vehicle control system is an accident avoidance system.

10. The drivetrain as set forth in claim 1 further including at least one of a global positioning system and a satellite weather system and wherein said controller further controls actuation of said first and second power disconnection devices based on readings from said at least one of a global positioning system and satellite weather system.

11. A method for controlling a drivetrain of a vehicle for transferring torque from a powertrain to a first and second set of wheels and including a first power disconnection device and a second power disconnection device each for adjusting the amount of torque transferred to at least one of the sets of wheels, said method comprising:
collecting visual data from a camera mounted to the vehicle as the vehicle travels across a road surface;
transmitting the visual data captured by the camera to a road analysis module;
processing the visual data captured by the camera with the road analysis module to calculate a coefficient of friction between tires of the vehicle and a road surface;
transmitting the calculated coefficient of friction to a controller;
actuating at least one of the first and second power disconnection devices with the controller based on the coefficient of friction determined by the road analysis module to adjust the amount of torque transferred to at least one of the wheels to prevent slipping of the wheels; and
transmitting the visual data from the camera to a vehicle control system that is separate from the road analysis module.

12. The method as set forth in claim 11 wherein the controller further actuates the at least one of the first and second power disconnection devices based on at least one driving characteristic of the vehicle measured by at least one sensor mounted on the vehicle.

13. The method as set forth in claim 12 wherein the driving characteristic measured by the at least one sensor includes at least one of drive mode status and wheel slip.

14. The method as set forth in claim 11 wherein said step of processing the visual data captured by the camera system with a road analysis module to calculate a coefficient of friction includes categorizing the visual data into distinct types of images, and comparing the categorized visual data to known road conditions.

15. The method as set forth in claim 14 further including determining CAN system operating parameters, and determining direct drive control inputs, and wherein said step of actuating at least one of the first and second power disconnection devices to adjust the amount of torque transferred to at least one of the wheels to prevent slipping of the at least one of the wheels is further based on the CAN system operating parameters, and the direct drive control inputs.

16. The method as set forth in claim 11 wherein said step of actuating at least one of the first and second power disconnection devices with the controller includes determining whether one or more components of the first and second driveline are in an active condition or inactive condition, wherein the components are in the active condition when connected to the powertrain and in the inactive condition when disconnected from the powertrain, and shifting the components between the active and inactive conditions based on at least the coefficient of friction determined by the road analysis module to prevent the wheels from slipping.

17. The method as set forth in claim 11 wherein the vehicle control system is an accident avoidance system.

18. The method as set forth in claim 11 wherein the first and second power disconnection devices are further actuated based on readings from at least one of

Assignees

• Magna Powertrain America Inc

Inventors

• Larkin Bradley R
• Quehenberger Johannes

Classifications

• B60K23/0808 Primary

  for varying torque distribution between driven axles, e.g. by transfer clutch · CPC title

• B60K2023/0858

  with electric means, e.g. electro-hydraulic means · CPC title

• B60K23/08 Primary

  for changing number of driven wheels {, for switching from driving one axle to driving two or more axles (B60K17/3515 takes precedence)} · CPC title

• B60W40/064

  Degree of grip · CPC title

• B60W2552/40

  Coefficient of friction · CPC title