Rule-based cruise control system and method

Patent metadata

Field	Value
Publication number	US-9352650-B2
Application number	US-201414567227-A
Country	US
Kind code	B2
Filing date	Dec 11, 2014
Priority date	Dec 12, 2013
Publication date	May 31, 2016
Grant date	May 31, 2016

Abstract

A rule-based vehicle cruise-control system includes a computer in a vehicle, the computer including a processor and a memory, and the computer is configured to control a vehicle speed within a first speed threshold according to a set point inputted to the cruise control system. The computer is configured to determine a current grade value is within a first grade threshold and adjust the set point to control the vehicle speed within a second speed threshold outside the first speed threshold. The computer is further configured to determine the current grade value is within a second grade threshold and adjust the set point to recover the vehicle speed to within the first speed threshold.

First claim

The invention claimed is:

1. A system comprising a computer in a vehicle, the computer comprising a processor and a memory, wherein the computer is configured to:
control a vehicle speed within a first speed threshold according to a set point inputted to a cruise control system;
determine a current grade value is within a first grade threshold;
adjust the set point to control the vehicle speed within a second speed threshold outside the first speed threshold;
determine the current grade value is within a second grade threshold; and
adjust the set point to recover the vehicle speed to within the first speed threshold.

2. The system of claim 1 , wherein adjusting the set point to control the vehicle speed within the second speed threshold includes:
operating a glide state of the cruise control system as long as the vehicle speed is within a third speed threshold, including one of selectively shifting a vehicle transmission to neutral and selectively initializing a deceleration fuel shutoff;
determining the current grade value is outside the second grade threshold; and
maintaining the vehicle speed outside the first speed threshold.

3. The system of claim 1 , wherein the computer is further configured to: modify the set point according to a forward vehicle detection signal.

4. The system of claim 1 , wherein the computer is further configured to: determine at least the first and second speed thresholds and the first and second grade thresholds according to a fuel efficiency performance value.

5. The system of claim 1 , wherein the computer is further configured to: invert a torque change signal to adjust the set point.

6. The system of claim 1 , wherein the first grade threshold is a first probabilistic grade threshold.

7. The system of claim 1 , wherein the computer is further configured to:
determine a recovery torque according to the current road grade and a fuel efficiency performance value; and
adjust the set point to recover the vehicle speed to within the first speed threshold according to the recovery torque.

8. A method comprising:
controlling a vehicle speed within a first speed threshold according to a set point inputted to a cruise control system by one of a driver and a forward vehicle sensor;
determining a current grade value is within a first grade threshold;
adjusting the set point to control the vehicle speed within a second speed threshold outside the first speed threshold;
determining the current grade value is within a second grade threshold; and
adjusting the set point to recover the vehicle speed to within the first speed threshold.

9. The method of claim 8 , wherein adjusting the set point to control the vehicle speed within the second speed threshold includes:
operating a glide state of the cruise control system as long as the vehicle speed is within a third speed threshold;
determining the current grade value is outside the second grade threshold; and
maintaining the vehicle speed outside the first speed threshold.

10. The method of claim 9 , wherein operating a glide state of the cruise control system includes one of shifting a vehicle transmission to neutral and deceleration fuel shutoff.

11. The method of claim 8 , further comprising: determining at least the first and second speed thresholds and the first and second grade thresholds according to a fuel efficiency performance value.

12. The method of claim 8 , further comprising: inverting a torque change signal to adjust the set point.

13. The method of claim 8 , wherein the first grade threshold is a first probabilistic grade threshold.

14. The method of claim 8 , further comprising:
determining a recovery torque according to the current road grade and a fuel efficiency performance value; and
adjusting the set point to recover the vehicle speed to within the first speed threshold according to the recovery torque.

15. A non-transitory computer-readable medium tangibly embodying computer-executable instructions that cause a processor to execute operations comprising:
controlling a vehicle speed within a first speed threshold according to a set point inputted to a cruise control system;
determining a current grade value is within a first grade threshold;
operating a glide state of the cruise control system as long as the vehicle speed is within a second speed threshold;
determining the current grade value is outside a second grade threshold; and
maintaining the vehicle speed outside the first speed threshold;
adjusting the set point to control the vehicle speed within a third speed threshold outside the first speed threshold;
determining the current grade value is within the second grade threshold; and
adjusting the set point to recover the vehicle speed to within the first speed threshold.

16. The non-transitory computer-readable medium of claim 15 , embodying instructions causing the processor to execute operations further comprising: modifying the set point according to a forward vehicle detection signal.

17. The non-transitory computer-readable medium of claim 15 embodying instructions causing the processor to execute operations further comprising: determining at least the first and second speed thresholds and the first and second grade thresholds according to a fuel efficiency performance value, and
wherein operating a glide state of the cruise control system includes one of selectively shifting a vehicle transmission to neutral and selectively initializing a deceleration fuel shutoff.

18. The non-transitory computer-readable medium of claim 15 embodying instructions causing the processor to execute operations further comprising: inverting a torque change signal to adjust the set point.

19. The non-transitory computer-readable medium of claim 15 wherein the first grade threshold is a first probabilistic grade threshold.

20. The non-transitory computer-readable medium of claim 15 embodying instructions causing the processor to execute operations further comprising:
determining a recovery torque according to the current road grade and a fuel efficiency performance value; and
adjusting the set point to recover the vehicle speed to within the first speed threshold according to the recovery torque.

Assignees

• Ford Global Tech Llc

Inventors

• Filev Dimitar Petrov
• Michelini John Ottavio
• Szwabowski Steven Joseph
• D Amato Anthony Mario

Classifications

• B60W2552/15

  Road slope, i.e. the inclination of a road segment in the longitudinal direction · CPC title

• B60W2520/10

  Longitudinal speed · CPC title

• B60W2710/0644

  Engine speed · CPC title

• B60W2510/0638

  Engine speed · CPC title

• B60W30/143 Primary

  Speed control (B60W30/16 takes precedence) · CPC title