Method and system for controlling a limited slip differential

Patent metadata

Field	Value
Publication number	US-10344844-B2
Application number	US-201715604047-A
Country	US
Kind code	B2
Filing date	May 24, 2017
Priority date	May 24, 2017
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

A system and method for electronically controlling a limited slip differential is disclosed. The method includes determining, by an electronic controller of a vehicle, a request for a limited-slip-differential coupling torque to be applied. The request is based upon an estimation of the vehicle's mass. The method also includes transmitting the request to an electronic limited slip differential of the vehicle. The electronic limited slip differential is configured to apply the requested limited-slip-differential coupling torque.

First claim

What is claimed is:

1. A method, the method comprising:
determining, by an electronic controller of a vehicle, a request for a limited-slip-differential coupling torque to be applied, wherein the request is based upon an estimation of the vehicle's mass; and
transmitting the request to an electronic limited slip differential of the vehicle, wherein the electronic limited slip differential is configured to apply the requested limited-slip-differential coupling torque.

2. The method of claim 1 , wherein the estimation of the vehicle's mass comprises an estimation of mass of a heavily-loaded or heavily-laden vehicle.

3. The method of claim 1 , wherein the configured application of the requested limited-slip-differential coupling torque results in a yaw moment and a wheel rotation that causes the vehicle to move along a wider curve when the vehicle turns.

4. The method of claim 1 , further comprising determining a difference between the estimated vehicle mass and a curb mass of the vehicle, wherein the determining the request for limited-slip-differential coupling torque to be applied comprises determining the coupling torque based on the determined difference.

5. The method of claim 1 , wherein the determining the request for limited-slip-differential coupling torque to be applied comprises changing a default coupling torque if the estimated vehicle mass exceeds a vehicle mass threshold, wherein the default coupling torque is a configured pre-load torque that is to be applied when the estimated vehicle mass does not exceed the vehicle mass threshold.

6. The method of claim 5 , wherein the changing the default coupling torque comprises changing the default coupling torque in accordance with a lookup table based on the vehicle's velocity.

7. The method of claim 5 , wherein the changing the default coupling torque comprises changing the default coupling torque in accordance with a lookup table based on a braking characteristic.

8. The method of claim 1 , wherein the determining the request for the limited-slip-differential coupling torque to be applied comprises determining that a hysteresis is to be applied to the limited-slip-differential coupling torque.

9. The method of claim 1 , wherein the determining the request for limited-slip-differential coupling torque to be applied comprises determining a yaw error and/or a slip target based on the estimation of the vehicle mass.

10. The method of claim 1 , wherein the determining the request for the limited-slip-differential coupling torque to be applied comprises determining a center of gravity based on the estimation of the vehicle mass.

11. A system within a vehicle, comprising:
an electronic controller configured to:
determine a request for a limited-slip-differential coupling torque to be applied, wherein the request is based upon an estimation of the vehicle's mass; and
transmit the request to an electronic limited slip differential of the vehicle, wherein the electronic limited slip differential is configured to apply the requested limited-slip-differential coupling torque.

12. The system of claim 11 , wherein the estimation of the vehicle's mass comprises an estimation of mass of a heavily-loaded or heavily-laden vehicle.

13. The system of claim 11 , wherein the configured application of the requested limited-slip-differential coupling torque results in a yaw moment and a wheel rotation that causes the vehicle to move along a wider curve when the vehicle turns.

14. The system of claim 11 , wherein the electronic controller is further configured to determine a difference between the estimated vehicle mass and a curb mass of the vehicle, wherein the determining the request for limited-slip-differential coupling torque to be applied comprises determining the coupling torque based on the determined difference.

15. The system of claim 11 , wherein the determining the request for limited-slip-differential coupling torque to be applied comprises changing a default coupling torque if the estimated vehicle mass exceeds a vehicle mass threshold, wherein the default coupling torque is a configured pre-load torque that is to be applied when the estimated vehicle mass does not exceed the vehicle mass threshold.

16. The system of claim 15 , wherein the changing the default coupling torque comprises changing the default coupling torque in accordance with a lookup table based on the vehicle's velocity.

17. The system of claim 15 , wherein the changing the default coupling torque comprises changing the default coupling torque in accordance with a lookup table based on a braking characteristic.

18. The system of claim 11 , wherein the determining the request for the limited-slip-differential coupling torque to be applied comprises determining that a hysteresis is to be applied to the limited-slip-differential coupling torque.

19. The system of claim 11 , wherein the determining the request for limited-slip-differential coupling torque to be applied comprises determining a yaw error and/or a slip target based on the estimation of the vehicle mass.

20. The system of claim 11 , wherein the determining the request for the limited-slip-differential coupling torque to be applied comprises determining a center of gravity based on the estimation of the vehicle mass.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Walter James R
• Kolk Jason Matthew
• Sundaram Satish
• Schweitzer Steven T

Classifications

• F16D48/06

  Control by electric or electronic means, e.g. of fluid pressure · CPC title

• F16D2500/5075

  Prevention or regulation of vehicle's wheel slip · CPC title

• F16H48/22 Primary

  using friction clutches or brakes · CPC title

• F16D2500/3107

  Vehicle weight · CPC title

• F16D2500/50287

  Torque control · CPC title