Vehicle speed control system

• US 9,908,528 B2
• Filed: 10/26/2016
• Issued: 03/06/2018
• 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: Kelly, James, Fairgrieve, Andrew, Woolliscroft, Daniel
• Primary Examiner(s): NGUYEN, TAN QUANG
• Application Number:
  US15/334,291
• Publication Number:
  US 20170043774A1
• Time in Patent Office: 496 Days
• Field of Search: 701 91
• CPC Class Codes: B60K 28/16 responsive to, or preventing, skidding of wheels brake control systems for vehicle drive stability B60T8/1755; arrangements responsive to a speed condition for adjusting wheel braking force B60T8/32; control of vehicle driving stability otherwise than by controlling the propulsion unit only B60W30/02; preventing wheel slippage by reducing power in rail vehicles B61C15/00
• CPC Class Codes: B60K 31/02 including electrically actuated servomechanism including an electric control system or a servomechanism in which the vehicle velocity affecting element is actuated electrically
• CPC Class Codes: B60K 31/04 and means for comparing one electrical quantity, e.g. voltage, pulse, waveform, flux, or the like, with another quantity of a like kind, which comparison means is involved in the development of an electrical signal which is fed into the controlling means
• 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 10/119 including control of all-wheel-driveline means, e.g. transfer gears or clutches for dividing torque between front and rear axle B60W10/14 takes precedence
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/26 Wheel slip
• CPC Class Codes: B60W 2552/05 Type of road, e.g. motorways, local streets, paved or unpaved roads
• CPC Class Codes: B60W 2720/10 Longitudinal speed
• CPC Class Codes: B60W 2720/28 Wheel speed
• CPC Class Codes: B60W 2720/30 Wheel torque
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 30/162 Speed limiting therefor
• CPC Class Codes: B60W 30/18172 Preventing, or responsive to skidding of wheels
• CPC Class Codes: B60W 40/06 Road conditions
• 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

Abstract

A vehicle speed control system for a vehicle having a plurality of wheels, the vehicle speed control system comprising one or more electronic control units configured to carry out a method that includes applying torque to at least one of the plurality of wheels, detecting a slip event between any one or more of the wheels and the ground over which the vehicle is travelling when the vehicle is in motion and providing a slip detection output signal in the event thereof. The method carried out by the one or more electronic control units further includes receiving a user input of a target speed at which the vehicle is intended to travel and maintaining the vehicle at the target speed independently of the slip detection output signal by adjusting the amount of torque applied to the at least one of the plurality of wheels.

Claims

1. A vehicle speed control system for a vehicle having a plurality of wheels, the vehicle speed control system configured to automatically control the speed of the vehicle to a target speed and comprising one or more electronic control units arranged to:

control the application of torque to at least one of the plurality of wheels;

detect a slip event between any one or more of the wheels and the surface over which the vehicle is travelling when the vehicle is in motion and provide a slip detection output signal in the event thereof;

receive a user input of a target set-speed at which the vehicle is intended to travel; and

control the application of torque to the at least one of the plurality of wheels for maintaining the vehicle at the target speed independently of the slip detection output signal by requesting the application of increased net torque to the at least one of the plurality of wheels when the vehicle speed needs to be increased to maintain the vehicle at the target speed wherein the magnitude of the requested increased net torque is reduced when an identified external force acts on the vehicle in a direction so as to cause positive acceleration.

2. The vehicle speed control system as claimed in claim 1 wherein the magnitude of the reduction of the requested increased net torque is proportional to the magnitude of the external force.

3. The vehicle speed control system as claimed in claim 1 wherein the magnitude of the requested increased net torque is increased when an identified external force acts on the vehicle in a direction so as to cause negative acceleration.

4. The vehicle speed control system as claimed in claim 3 wherein the magnitude of the increase of the requested increased net torque is proportional to the magnitude of the external force.

5. The vehicle speed control system as claimed in claim 1, wherein said one or more electronic control unit is arranged to:

determine the magnitude and direction of an external force operating on the vehicle;

compare the current speed with the target speed and providing an output indicative of the difference between the current speed and the target speed; and

evaluating the torque to be applied to at least one of the vehicle wheels in dependence on the output, and

increasing or decreasing the magnitude of the evaluated torque in dependence on the determined magnitude and direction of an external force operating on the vehicle.

6. The vehicle speed control system as claimed in claim 5, wherein said one or more electronic control unit is arranged to apply torque to at least two wheels of the vehicle simultaneously.

7. The vehicle speed control system as claimed in claim 5, wherein said one or more electronic control unit is arranged to apply torque to at least four wheels of the vehicle simultaneously.

8. A vehicle comprising a control system as claimed in claim 1.

17. A vehicle comprising a control system as claimed in claim 1 and comprising a vehicle speed control system configured to automatically control the speed of the vehicle to a target speed and comprising one or more electronic control units arranged to:

control the application of torque to at least one of the plurality of wheels;

detect a slip event between any one or more of the wheels and the surface over which the vehicle is travelling when the vehicle is in motion and provide a slip detection output signal in the event thereof;

receive a user input of a target set-speed at which the vehicle is intended to travel; and

control the application of torque to the at least one of the plurality of wheels for maintaining the vehicle at the target speed independently of the slip detection output signal by requesting a reduction of net torque applied to the vehicle wheels when the vehicle speed needs to be decreased to maintain the vehicle at the target speed wherein the magnitude of the requested reduction of net torque is increased when an identified external force acts on the vehicle in a direction so as to cause positive acceleration.

9. A vehicle speed control system for a vehicle having a plurality of wheels, the vehicle speed control system configured to automatically control the speed of the vehicle to a target speed and comprising one or more electronic control units arranged to:

control the application of torque to at least one of the plurality of wheels;

detect a slip event between any one or more of the wheels and the surface over which the vehicle is travelling when the vehicle is in motion and provide a slip detection output signal in the event thereof;

receive a user input of a target set-speed at which the vehicle is intended to travel; and

control the application of torque to the at least one of the plurality of wheels for maintaining the vehicle at the target speed independently of the slip detection output signal by requesting a reduction of net torque applied to the vehicle wheels when the vehicle speed needs to be decreased to maintain the vehicle at the target speed wherein the magnitude of the requested reduction of net torque is increased when an identified external force acts on the vehicle in a direction so as to cause positive acceleration.

10. The vehicle speed control system as claimed in claim 9 wherein the magnitude of the increase of the reduction of net torque is proportional to the magnitude of the external force.

11. The vehicle speed control system as claimed in claim 9 wherein the magnitude of the requested reduction of net torque is decreased when an identified external force acts on the vehicle in a direction so as to cause negative acceleration.

12. The vehicle speed control system as claimed in claim 11 wherein the magnitude of the decrease of the requested reduction of net torque is proportional to the magnitude of the external force.

13. The vehicle speed control system as claimed in claim 9, wherein said one or more electronic control unit is arranged to:

determine the magnitude and direction of an external force operating on the vehicle;

compare the current speed with the target speed and providing an output indicative of the difference between the current speed and the target speed; and

evaluating the torque to be applied to at least one of the vehicle wheels in dependence on the output, and

increasing or decreasing the magnitude of the evaluated torque in dependence on the determined magnitude and direction of an external force operating on the vehicle.

14. The vehicle speed control system as claimed in claim 13, wherein said one or more electronic control unit is arranged to apply torque to at least two wheels of the vehicle simultaneously.

15. The vehicle speed control system as claimed in claim 13, wherein said one or more electronic control unit is arranged to apply torque to at least four wheels of the vehicle simultaneously.

16. A vehicle comprising a control system as claimed in claim 9.

18. A method of automatically controlling a speed to a target speed of a vehicle having a plurality of wheels, the method comprising:

applying torque to at least one of the plurality of wheels;

detecting a slip event between any one or more of the wheels and the ground over which the vehicle is travelling when the vehicle is in motion and providing a slip detection output signal in the event thereof;

receiving a user input of a target set-speed at which the vehicle is intended to travel; and

automatically maintaining the vehicle at the target speed independently of the slip detection output signal by requesting the application of increased net torque to the at least one of the plurality of wheels when the vehicle speed needs to be increased to maintain the vehicle at the target speed wherein the magnitude of the requested increased net torque is reduced when an identified external force acts on the vehicle in a direction so as to cause positive acceleration.

19. A method of automatically controlling a speed to a target speed of a vehicle having a plurality of wheels, the method comprising:

applying torque to at least one of the plurality of wheels;

detecting a slip event between any one or more of the wheels and the ground over which the vehicle is travelling when the vehicle is in motion and providing a slip detection output signal in the event thereof;

receiving a user input of a target set-speed at which the vehicle is intended to travel; and

automatically maintaining the vehicle at the target speed independently of the slip detection output signal by requesting a reduction of net torque applied to the vehicle wheels when the vehicle speed needs to be decreased to maintain the vehicle at the target speed wherein the magnitude of the requested reduction of net torque is increased when an identified external force acts on the vehicle in a direction so as to cause positive acceleration.