Kevin G Leppek

6405117, Jun 11, 2002

Jun 21, 2001

09/885191

Allen John Walenty - Macomb MI
Kevin Gerard Leppek - Rochester Hills MI
David Alan Thatcher - Troy MI

General Motors Corporation - Detroit MI

G06G 776

701 70, 701 29, 701 35, 73121, 73129

An improved method of diagnosing conditions of a vehicle braking system that degrade the braking effectiveness informs the driver of the condition so that repair or adjustment can be timely made. The relationship between brake pedal position and vehicle deceleration is determined during a calibration interval to construct a calibration table of brake effectiveness, and then periodically over the life of the braking system to develop a current brake effectiveness table. Braking system abnormalities that impair the braking effectiveness are diagnosed by analyzing the table values.

6490518, Dec 3, 2002

Jun 29, 2001

09/893483

Allen John Walenty - Macomb MI
Kevin Gerard Leppek - Rochester Hills MI

General Motors Corporation - Detroit MI

B60T 800

701 71, 701 80, 303176, 303157

An improved anti-lock brake control method adaptively determines exit criteria for terminating anti-lock brake control based on rate of brake pedal release and estimates of the brake torque and road surface coefficient of friction. The brake torque and road surface coefficient of friction are estimated based on a periodically updated characterization of the relationship between brake pedal position and vehicle deceleration.

6513886, Feb 4, 2003

May 7, 1996

08/646189

John Andrew Weber - Farmington Hills MI
Alfred Russell Robertson - Southfield MI
Kevin Gerard Leppek - Rochester MI
Alexander Kade - Grosse Pointe Woods MI
Allen John Walenty - Macomb MI
David Alan Thatcher - Troy MI

General Motors Corporation - Detroit MI

B60T 858

303146, 303177, 303183, 303184, 303185

A brake system control method for use in a vehicle in which wheel speed normalization factors are iteratively updated, comprising the steps of: monitoring a plurality of wheel speed signals from a plurality of wheel speed sensors; determining for each wheel a wheel acceleration responsive to the wheel speed signal; determining an acceleration dead band for each wheel, wherein the acceleration dead band is proportional to a measure of vehicle acceleration; comparing the wheel acceleration to the dead band; and if the magnitude of the wheel acceleration is greater than the magnitude of the dead band, inhibiting update of the normalization factors.

6553304, Apr 22, 2003

Jun 18, 2001

09/882795

Allen John Walenty - Macomb MI
Kevin Gerard Leppek - Rochester Hills MI
David Alan Thatcher - Troy MI

General Motors Corporation - Detroit MI

B60T 770

701 71

An improved anti-lock brake control method in which the brake pressure reduction initiated upon detection of insipient wheel lock is adaptively determined based on a periodically updated characterization of the relationship between brake pedal position and vehicle deceleration. The brake torque and vehicle weight are estimated based on the characterization data, corrected for variation in brake heating, and used to compute the surface coefficient of friction, which in turn, is used to schedule the initial anti-lock brake pressure reduction for optimal braking system performance.

6618660, Sep 9, 2003

Oct 15, 2001

09/976886

Allen John Walenty - Macomb MI
Kevin Gerard Leppek - Rochester Hills MI

General Motors Corporation - Detroit MI

B60B 3900

701 71, 701 72, 701 73, 701 74, 701 75, 701 76, 701 38, 280 5507, 303155

An improved anti-lock rear brake yaw control method utilizes a measure of braking intensity to regulate both the initiation of yaw control and the anti-lock braking control parameters once yaw control is initiated. The brake torque and the rate of brake pedal depression provide measures of braking intensity, and are used to develop variable slip and deceleration thresholds to which the rear wheel differential slip and deceleration are compared. The variable thresholds permit initiation of yaw control at relatively low levels of differential wheel slip or deceleration during panic braking, while requiring higher levels of differential wheel slip or deceleration to initiate yaw control during moderate braking. Once yaw control is initiated, the slip and deceleration thresholds are utilized to adaptively adjust the slip and deceleration targets, so that the targets are set in accordance with the slip and deceleration of the rear wheel with the lowest coefficient of friction during panic braking, and at higher levels during moderate braking.

6704635, Mar 9, 2004

Jun 26, 2002

10/184261

Allen John Walenty - Macomb MI
Kevin Gerard Leppek - Rochester Hills MI
David Alan Thatcher - Troy MI

General Motors Corporation - Detroit MI

G06F 700

701 71, 701 70, 701 73

A vehicle anti-lock braking system includes a brake pedal and a brake modulator. The brake system reduces braking pressure by an initial pressure reduction after detecting insipient wheel lock. Vehicle deceleration is measured as a function of brake pedal position. A first table is updated with the vehicle deceleration and the brake pedal position. A coefficient of friction of a road surface is estimated based on the first table. Wheel slip and deceleration target thresholds are determined based on the coefficient of friction. The wheel slip and deceleration target thresholds are used to populate a command table for the anti-lock braking system. Brake heat, brake torque, vehicle weight and grade are estimated. Release and apply pressures are calculated from an adjusted coefficient of friction, a coefficient of friction and the grade.

6728621, Apr 27, 2004

Oct 4, 2002

10/264685

Allen John Walenty - Macomb MI
Kevin Gerard Leppek - Rochester Hills MI
David Alan Thatcher - Troy MI

General Motors Corporation - Detroit MI

B60B 3900

701 71, 701 72, 701 73, 701 79, 701 80, 303153, 303155

A method and apparatus for operating a vehicle anti-lock braking system includes a brake pedal and a brake modulator that reduces braking pressure by an initial pressure reduction after detecting insipient wheel lock. Vehicle deceleration is measured as a function of brake pedal position. A first table is updated with the vehicle deceleration and the brake pedal position. A coefficient of friction of a road surface is estimated based on the first table. A slip target for at least one wheel is estimated and is based on an estimated maximum slip of the at least one wheel before losing traction minus an estimated potential for vehicle rollover. A deceleration target for at least one wheel is estimated and is based on an estimated maximum deceleration of the at least one wheel before losing traction minus the estimated potential for vehicle rollover.

6748311, Jun 8, 2004

May 8, 2003

10/431743

Allen J. Walenty - Macomb MI
Kevin G. Leppek - Rochester Hills MI
Calvin E. Wolf - Mt. Clemens MI

General Motors Corporation - Detroit MI

G06G 776

701 70, 701 78, 701 79

Apparatus and methods are provided for controlling movement of an automobile in a pitched position. The apparatus has an attitude sensor that is configured to determine a pitch of the automobile and a speed sensor that is configured to determine a speed of the automobile. In addition, the apparatus has a braking mechanism that is configured to inhibit movement of the automobile and a controller that is configured to control the braking mechanism. The controller is configured to receive the pitch and the speed determined by the attitude sensor and the speed sensor, respectively, and control the braking mechanism based at least in part upon an evaluation of the pitch and the speed in order to inhibit movement of the automobile in the pitched position.