Grade logic braking system

Patent metadata

Field	Value
Publication number	US-2016264122-A1
Application number	US-201514644138-A
Country	US
Kind code	A1
Filing date	Mar 10, 2015
Priority date	Mar 10, 2015
Publication date	Sep 15, 2016
Grant date	—

Abstract

A vehicle and methods of braking the vehicle on a downhill grade as automatically implemented by a computing device are disclosed. One method includes detecting application of a vehicle brake and detecting acceleration of the vehicle while the vehicle traverses the downhill grade. Based on detection of the application of the vehicle brake and detection of the acceleration of the vehicle, the method also includes sending a command to downshift a transmission of the vehicle. If, after the downshift of the transmission, the application of the vehicle brake is not detected for a threshold time, the acceleration of the vehicle falls below a threshold acceleration, or the downhill grade falls below a threshold grade, the method can further include sending a command to upshift the transmission.

First claim

What is claimed is:

1 . A method of braking a vehicle on a downhill grade, comprising:
detecting application of a vehicle brake while the vehicle traverses the downhill grade; detecting acceleration of the vehicle while the vehicle traverses the downhill grade; and based on detection of the application of the vehicle brake and detection of the acceleration of the vehicle, sending a command to downshift a transmission of the vehicle.

2 . The method of claim 1 , wherein detecting the application of the vehicle brake is based on at least one of detecting a driver input to a brake pedal and determining a brake switch status.

3 . The method of claim 1 , wherein detecting the acceleration of the vehicle is based on input from one or more wheel speed sensors.

4 . The method of claim 1 , further comprising:
if, after the downshift of the transmission, the application of the vehicle brake is not detected for a threshold time, sending a command to upshift the transmission.

5 . The method of claim 4 , wherein the threshold time is three seconds.

6 . The method of claim 1 , further comprising:
if, after the downshift of the transmission, the acceleration of the vehicle falls below a threshold acceleration, sending a command to upshift the transmission.

7 . The method of claim 6 , wherein the threshold acceleration is ten percent of the acceleration of gravity.

8 . The method of claim 1 , further comprising:
detecting the downhill grade based on input from an inclinometer.

9 . The method of claim 8 , further comprising:
if, after the downshift of the transmission, the downhill grade falls below a threshold grade, sending a command to upshift the transmission.

10 . The method of claim 9 , wherein the threshold grade is a predetermined grade percentage.

11 . A computing device, comprising:
one or more processors for controlling operations of the computing device; and a memory for storing data and program instructions used by the one or more processors, wherein the one or more processors are configured to execute instructions stored in the memory to:
detect application of a vehicle brake while a vehicle traverses a downhill grade;
detect acceleration of the vehicle while the vehicle traverses the downhill grade; and
based on detection of the application of the vehicle brake and detection of the acceleration of the vehicle, send a command to downshift a transmission of the vehicle.

12 . The computing device of claim 11 , wherein the one or more processors are further configured to:
if, after the downshift of the transmission, the application of the vehicle brake is not detected for a threshold time, send a command to upshift the transmission.

13 . The computing device of claim 11 , wherein the one or more processors are further configured to:
if, after the downshift of the transmission, the acceleration of the vehicle falls below a threshold acceleration, send a command to upshift the transmission.

14 . The computing device of claim 11 , wherein the one or more processors are further configured to:
detect the downhill grade based on input from an inclinometer.

15 . The computing device of claim 14 , wherein the one or more processors are further configured to:
if, after the downshift of the transmission, the downhill grade falls below a threshold grade, send a command to upshift the transmission.

16 . A vehicle, comprising:
a vehicle brake; and a computing device in communication with the vehicle brake, comprising:
one or more processors for controlling operations of the computing device; and
a memory for storing data and program instructions used by the one or more processors, wherein the one or more processors are configured to execute instructions stored in the memory to:
detect application of the vehicle brake while the vehicle traverses a downhill grade;
detect acceleration of the vehicle while the vehicle traverses the downhill grade; and
based on detection of the application of the vehicle brake and detection of the acceleration of the vehicle, send a command to downshift a transmission of the vehicle.

17 . The vehicle of claim 16 , wherein the one or more processors are further configured to:
if, after the downshift of the transmission, the application of the vehicle brake is not detected for a threshold time, send a command to upshift the transmission.

18 . The vehicle of claim 16 , wherein the one or more processors are further configured to:
if, after the downshift of the transmission, the acceleration of the vehicle falls below a threshold acceleration, send a command to upshift the transmission.

19 . The vehicle of claim 16 , wherein the one or more processors are further configured to:
detect the downhill grade based on input from an inclinometer.

20 . The vehicle of claim 19 , wherein the one or more processors are further configured to:
if, after the downshift of the transmission, the downhill grade falls below a threshold grade, send a command to upshift the transmission.

Assignees

• Toyota Motor Eng & Mfg North America Inc

Inventors

• Gauthier Christopher T

Classifications

• F16H61/21

  Providing engine brake control · CPC title

• B60W2520/105

  Longitudinal acceleration · CPC title

• F16H2061/0237

  Selecting ratios for providing engine braking · CPC title

• B60W2550/142

  Operations & Transport · mapped topic

• F16H2059/663

  Road slope · CPC title