VEHICLE SPEED CONTROL SYSTEM AND METHOD WITH EXTERNAL FORCE COMPENSATION

• US 20150232092A1
• Filed: 08/15/2013
• Published: 08/20/2015
• Est. Priority Date: 08/16/2012
• Status: Active Grant

• Current Assignee: Jaguar Land Rover Limited (TATA Motors Limited)
• Original Assignee: Jaguar Land Rover Limited (TATA Motors Limited)
• Inventors: Fairgrieve, Andrew, Woolliscroft, Daniel, Kelly, James
• Granted Patent: US 9,630,623 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60L 3/10 Indicating wheel slip ; Correction of wheel slip
• CPC Class Codes: B60L 3/106 for maintaining or recovering the adhesion of the drive wheels
• CPC Class Codes: B60T 2201/04 Hill descent control
• CPC Class Codes: B60T 2210/14 Rough roads, bad roads, gravel roads
• CPC Class Codes: B60T 2210/16 Off-road driving conditions
• CPC Class Codes: B60T 2220/04 Pedal travel sensor, stroke sensor; Sensing brake request
• CPC Class Codes: B60T 2260/06 Active Suspension System
• CPC Class Codes: B60T 8/175 Brake regulation specially adapted to prevent excessive wheel spin during vehicle acceleration, e.g. for traction control safety devices for propulsion unit control responsive to, or preventing, skidding of wheels B60K28/16
• CPC Class Codes: B60W 2520/04 Vehicle stop
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2530/16 Driving resistance
• CPC Class Codes: B60W 2552/05 Type of road, e.g. motorways, local streets, paved or unpaved roads
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2720/30 Wheel torque
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 30/18118 Hill holding
• CPC Class Codes: B60W 30/18172 Preventing, or responsive to skidding of wheels
• CPC Class Codes: B60Y 2200/20 Off-Road Vehicles
• CPC Class Codes: F16H 2061/0234 Adapting the ratios to special vehicle conditions
• CPC Class Codes: F16H 59/66 Road conditions, e.g. slope, slippery
• CPC Class Codes: F16H 61/0213 : characterised by the method for generating shift signals
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility

Abstract

A method for operating a speed control system of a vehicle is provided. The method comprises detecting an external force acting on the vehicle wherein the external force has an accelerating or decelerating effect on the vehicle. The method further comprises automatically adjusting a rate of change of at least one component of a net torque being applied to one or more wheels of the vehicle to compensate for the accelerating or decelerating effect of the external force on the vehicle. A system for controlling the speed of a vehicle comprising an electronic control unit configured to perform the above-described methodology is also provided.

Claims

1. A method of operating a speed control system of a vehicle, comprising:

detecting an external force acting on the vehicle wherein the external force has a accelerating or decelerating effect on the vehicle;

automatically adjusting a rate of change of at least one component of a net torque being applied to one or more wheels of the vehicle to compensate for the accelerating or decelerating effect of the external force on the vehicle, wherein

the adjusting step comprises applying a predetermined gain to at least one component of the net torque being applied to one or more wheels of the vehicle, thereby increasing or decreasing the rate at which the at least one component of the net torque is changed.

2. The method of claim 1, further comprising receiving a command to change a set-speed of the speed control system from a first set-speed to a target set-speed, and wherein the adjusting step comprises adjusting the rate of change of at least one component of the net torque being applied to accelerate or decelerate the vehicle to the target set-speed.

3. The method of claim 2, wherein the external force has a decelerating effect as a result of the vehicle ascending a gradient, and further wherein if the received command to change the set-speed would result in a rate of change of at least one component of the net torque being applied such that the net torque would be insufficient to maintain vehicle progress up the gradient, the method further comprises decreasing the rate of change of at least one component of the net torque being applied to prevent movement of the vehicle down the gradient:

the method further comprising activating a hill hold assistance system of the vehicle configured to maintain the vehicle stationary on the gradient until sufficient net torque has been generated to prevent movement down the gradient or to resume motion of the vehicle up the gradient.

6. The method of claim 1, wherein the adjusting step comprises adjusting the rate of change of at least one component of the net torque being applied to accelerate or decelerate the vehicle to the target set-speed in accordance with a predetermined acceleration profile, and wherein said acceleration profile comprises an acceleration corridor comprising a range between a desired acceleration and a maximum desired acceleration.

8. The method of claim 1, wherein the detecting step comprises one of:

comparing the longitudinal acceleration of the vehicle to a predetermined acceleration profile and detecting that an external force is acting on the vehicle when the longitudinal acceleration of the vehicle diverges from the predetermined acceleration profile;

evaluating one or more operational parameters of the vehicle, and detecting that an external force is acting on the vehicle based on that evaluation; and

detecting that the vehicle is traversing a terrain that will cause an external force to be applied to the vehicle.

12. The method of claim 1,

wherein the adjustment to the rate of change of at least one component of the net torque being applied is dependent upon the magnitude of the force acting on the vehicle.

14. The method of claim 1, wherein the component of the net torque comprises one or more of a retarding torque and a drive torque being applied to one or more wheels.

15. The method of claim 14, wherein the adjusting step further comprises adjusting the rate at which one or both of the retarding torque and drive torque applied to one or more wheels of the vehicle is reduced or increased.

31. A vehicle comprising the system as recited in claim 1.

32. A carrier medium carrying a computer-readable code for controlling a vehicle to carry out the method according claim 1.

4-5. -5. (canceled)

7. (canceled)

9-11. -11. (canceled)

13. (canceled)

16. A system for controlling the speed of a vehicle, comprising:

an electronic control unit (ECU), the ECU configured to;

detect an external force acting on the vehicle wherein the external force has an accelerating or decelerating effect on the vehicle; and

automatically adjust a rate of change of at least one component of a net torque being applied to one or more wheels of the vehicle to compensate for the accelerating or decelerating effect of the external force on the vehicle;

wherein the ECU is configured to adjust the rate of change of at least one component of the net torque being applied by applying a predetermined gain to at least one component of the net torque being applied, thereby increasing or decreasing the rate at which the at least one component of the net torque is changed.

17. The system of claim 16, wherein the ECU is further configured to receive a command to change a set-speed of the system from a first set-speed to a target set-speed, and wherein the ECU is configured to adjust the rate of change of at least one component of the net torque being applied to one or more wheels of the vehicle by adjusting the rate of change of at least one component of the net torque being applied to accelerate or decelerate the vehicle to the target set-speed.

18. The system of claim 17, wherein when the external force has a decelerating effect on the vehicle as a result of the vehicle ascending a gradient, and further wherein the ECU is configured to determine if the received command to change the set-speed would result in a rate of change of at least one component of the net torque being applied being such that the net torque would be insufficient to maintain vehicle progress up the gradient, and in response thereto the ECU is further configured to decrease the rate of change of at least one component of the net torque being applied to prevent movement down the gradient.

19. The system of claim 18, wherein the ECU is further configured to activate a hill hold assistance system of the vehicle to maintain the vehicle stationary on the gradient until sufficient net torque has been generated to prevent movement down the gradient or to resume motion of the vehicle up the gradient.

20. The system of claim 17, wherein the ECU is configured to detect the external force acting on the vehicle in response to receiving the command to change the set-speed of the system.

21. The system of claim 17, wherein the ECU is configured to adjust the rate of change of at least one component of the net torque being applied to one or more wheels of the vehicle in accordance with a predetermined acceleration profile, and wherein said acceleration profile comprises an acceleration corridor comprising a range between a desired acceleration and a maximum desired acceleration.

23. The system of claim 16, wherein the ECU is configured to detect the external force acting on the vehicle by:

comparing the longitudinal acceleration of the vehicle to a predetermined acceleration profile and detecting that an external force is acting on the vehicle when the longitudinal acceleration of the vehicle diverges from the predetermined acceleration profile;

or

evaluating one or more operational parameters of the vehicle, and detecting that an external force is acting on the vehicle based on that evaluation;

or

detecting that the vehicle is traversing a terrain that will cause an external force to be applied to the vehicle.

27. The system of claim 16, wherein the ECU is configured to adjust the rate of change of at least one component of the net torque being applied depending upon the magnitude of the force acting on the vehicle.

28. The system of claim 16, wherein the ECU is configured to adjust the rate of change of at least one component of the net torque being applied by applying a predetermined gain to at least one component of the net torque being applied, thereby increasing or decreasing the rate at which the at least one component of the net torque is changed.

29. The system of claim 16, wherein the component of the net torque comprises one or more of a retarding torque and a drive torque being applied to one or more wheels, and wherein the ECU is configured to adjust the rate of change of at least one component of the net torque being applied by adjusting the rate at which one or both of the retarding torque and drive torque applied to one or more wheels is reduced or increased.

22. (canceled)

24-26. -26. (canceled)

30. (canceled)