Rule-based cruise control system and method

• US 9,352,650 B2
• Filed: 12/11/2014
• Issued: 05/31/2016
• Est. Priority Date: 12/12/2013
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Filev, Dimitar Petrov, Michelini, John Ottavio, Szwabowski, Steven Joseph, D'Amato, Anthony Mario
• Primary Examiner(s): Zanelli, Michael J
• Application Number:
  US14/567,227
• Publication Number:
  US 20150165905A1
• Time in Patent Office: 537 Days
• US Class Current: 1/1
• CPC Class Codes: B60K 31/00 Vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator fittings acting on two or more sub-units B60W30/14; speedometers G01P; systems or devices for controlling speed in general G05D13/00 ; in traffic anti-collision system for road vehicles G08G1/16
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 2030/1809 Without torque flow between driveshaft and engine, e.g. with clutch disengaged or transmission in neutral
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0647 Coasting condition
• CPC Class Codes: B60W 2510/1005 Transmission ratio engaged
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/1005 Transmission ratio engaged
• CPC Class Codes: B60W 2720/10 Longitudinal speed
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 30/18072 Coasting
• CPC Class Codes: Y02T 10/40 Engine management systems

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.

Claims

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.