US 10,207,708 B2 · System and method for minimizing shift cycling for engine operation using cruise control

Abstract

A system and method for minimizing shift cycling for low speed engine operation with a vehicle cruise control. A vehicle control system operating in a cruise control mode determines a deficiency in vehicle speed between a measured vehicle speed and a cruise set speed. The deficiency is determined by comparing the vehicle speed to the cruise set speed, and includes using the compared value to find a cruise speed margin, which is continuously updated. While the cruise control system is active, the control system logic determines the time at which a transmission upshift occurs based on the cruise speed margin. The vehicle speed, at which the upshift is made, is determined as a function of the updated cruise speed margin. An upshift is not made, if a likely drop in vehicle speed would result in the event a downshift would occur once the upshift is made.

Claims19

Dependent claims

A vehicle speed control method for controlling a speed of a vehicle including a cruise control system and an engine developing an engine torque to drive a transmission having a plurality of gears, wherein the transmission is configured to upshift from a lower gear to a higher gear having a lower RPM than an RPM of the lower gear, is configured to downshift from the higher gear to the lower gear having a higher RPM than the RPM of the higher gear, and is configured to move the vehicle in response to the engine torque, the method comprising:

identifying a cruise set speed maintained by the cruise control system;
identifying when the vehicle speed is less than the cruise set speed;
determining a cruise margin from a comparison of the identified vehicle speed to the identified cruise set speed;
and
modifying the cruise margin over a period of time by continuously increasing the cruise margin until the vehicle speed falls below a downshift speed threshold.

2 more elements

A vehicle control system configured to control a vehicle speed of a vehicle including a cruise control system configured to provide a cruise set speed, an engine developing an engine torque to drive a transmission having a plurality of gears, wherein the transmission is configured to upshift from a lower gear to a higher gear having a lower RPM than an RPM of the lower gear, is configured to downshift from the higher gear to the lower gear having a higher RPM than the RPM of the higher gear, and is configured to move the vehicle in response to the engine torque, the vehicle control system including:

a memory device configured to store program instructions;
and
a vehicle system control module operably connected to the transmission and to the memory device, the vehicle system control module configured to execute the stored program instructions to:
identify a cruise set speed maintained by the cruise control system;
identify when the vehicle speed is less than the cruise set speed;
determine a cruise margin from a comparison of the vehicle speed to the cruise set speed;
and
modify the cruise margin over a period of time by continuously increasing the cruise margin until the vehicle speed falls below a downshift speed threshold.

5 more elements

Dependencies are inferred from the claim text.

System and method for minimizing shift cycling for engine operation using cruise control

Life of this patent

System and method for minimizing shift cycling for engine operation using cruise control

Life of this patent

Abstract

Claims19