IP Library Granted Patent US 7,909,730
Granted Patent B2
US 7,909,730 · App. 11/934,322 · Granted Mar 22, 2011

Method for vehicle creep torque control

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Quick Facts
Patent No.
US 7,909,730
App. No.
11/934,322
Granted
Mar 22, 2011
Kind
B2
Abstract

A vehicle and a method of operation. The method of operating the vehicle may include a method of controlling a creep torque in a vehicle having a powertrain configured to provide variable creep torque. The method may comprise the steps of: detecting a vehicle creep torque condition, determining a brake torque, and adjusting a creep torque applied by the powertrain based on the brake torque.

Claims (21)

1. A method of controlling a creep torque in a vehicle having a powertrain configured to provide variable creep torque, the method comprising the steps of:

(a) detecting a vehicle creep torque condition;

(b) determining a brake torque; and

(c) adjusting a creep torque applied by the powertrain based on the brake torque, wherein the applied creep torque is adjusted to zero when the brake torque is greater than a predetermined amount of brake torque.

2. The method of claim 1 including (d) determining a new brake torque after step (b), and (e) calculating a rate of change of brake torque based on the brake torque and the new brake torque, and wherein step (c) is further defined by the adjustment in the creep torque being based on the rate of change of brake torque.

3. The method of claim 2 wherein step (c) is further defined by a greater creep torque being applied when the rate of change of brake torque in a direction of reduced brake torque is greater, and a relatively lower creep torque is applied when the rate of change of brake torque in the direction of reduced brake torque is relatively lower.

4. The method of claim 1 wherein step (b) is further defined by determining the brake torque based on input from a brake position sensor that detects a position of a brake pedal.

5. A method of controlling a creep torque in a vehicle having a powertrain configured to provide variable creep torque, the method comprising the steps of:

(a) detecting a vehicle creep torque condition;

(b) determining a brake torque;

(c) determining a new brake torque;

(d) calculating a rate of change of brake torque based on the brake torque and the new brake torque; and

(e) adjusting a creep torque applied by the powertrain based on the new brake torque and the rate of change of brake torque.

6. The method of claim 5 wherein step (e) is further defined by a greater creep torque being applied when the rate of change of brake torque in a direction of reduced brake torque is greater, and a relatively lower creep torque is applied when the rate of change of brake torque in the direction of reduced brake torque is relatively lower.

7. The method of claim 5 wherein step (e) is further defined by the applied creep torque being adjusted to zero when the brake torque is greater than a predetermined amount of brake torque.

8. The method of claim 5 wherein step (b) is further defined by determining the brake torque based on input from a brake position sensor that detects a position of a brake pedal.

9. A method of controlling a creep torque in a vehicle having a powertrain configured to provide variable creep torque, the method comprising the steps of:

(a) detecting a vehicle creep torque condition;

(b) determining a brake torque based on input from a brake position sensor that detects a position of a brake pedal; and

(c) adjusting a creep torque applied by the powertrain based on the brake torque.

10. The method of claim 9 including (d) determining a new brake torque after step (b), and (e) calculating a rate of change of brake torque based on the brake torque and the new brake torque, and wherein step (c) is further defined by the adjustment in the creep torque being based on the rate of change of brake torque, and a greater creep torque being applied when the rate of change of brake torque in a direction of reduced brake torque is greater, and a relatively lower creep torque is applied when the rate of change of brake torque in the direction of reduced brake torque is relatively lower.

Assignments (12)
RELEASE OF SECURITY INTEREST Recorded Nov 7, 2014
From: WILMINGTON TRUST COMPANY
To: GM GLOBAL TECHNOLOGY OPERATIONS LLC
Reel/Frame 034185/0587 →
CHANGE OF NAME Recorded Feb 10, 2011
From: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
To: GM GLOBAL TECHNOLOGY OPERATIONS LLC
Reel/Frame 025781/0035 →
SECURITY AGREEMENT Recorded Nov 8, 2010
From: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
To: WILMINGTON TRUST COMPANY
Reel/Frame 025324/0057 →
RELEASE OF SECURITY INTEREST Recorded Nov 5, 2010
From: UAW RETIREE MEDICAL BENEFITS TRUST
To: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Reel/Frame 025315/0001 →
RELEASE OF SECURITY INTEREST Recorded Nov 4, 2010
From: UNITED STATES DEPARTMENT OF THE TREASURY
To: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Reel/Frame 025245/0780 →
SECURITY AGREEMENT Recorded Aug 28, 2009
From: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
To: UAW RETIREE MEDICAL BENEFITS TRUST
Reel/Frame 023162/0187 →
SECURITY AGREEMENT Recorded Aug 27, 2009
From: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
To: UNITED STATES DEPARTMENT OF THE TREASURY
Reel/Frame 023156/0215 →
RELEASE OF SECURITY INTEREST Recorded Aug 21, 2009
From: CITICORP USA, INC. AS AGENT FOR BANK PRIORITY SECURED PARTIES; CITICORP USA, INC. AS AGENT FOR HEDGE PRIORITY SECURED PARTIES
To: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Reel/Frame 023155/0880 →
RELEASE OF SECURITY INTEREST Recorded Aug 20, 2009
From: UNITED STATES DEPARTMENT OF THE TREASURY
To: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Reel/Frame 023124/0670 →
SECURITY AGREEMENT Recorded Apr 16, 2009
From: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
To: CITICORP USA, INC. AS AGENT FOR BANK PRIORITY SECURED PARTIES; CITICORP USA, INC. AS AGENT FOR HEDGE PRIORITY SECURED PARTIES
Reel/Frame 022554/0479 →
SECURITY AGREEMENT Recorded Feb 3, 2009
From: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
To: UNITED STATES DEPARTMENT OF THE TREASURY
Reel/Frame 022201/0363 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 2, 2007
From: SCHWARZ, JONATHAN R.; KIDSTON, KEVIN S.; LOGAN, JON K.
To: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Reel/Frame 020060/0448 →