Delphi Technologies, Inc.

Gm Global Technolgoy Operations, Inc.

Other

Hsien Heng Chen

Edward John Bedner

Yuen-Kwok Chin

Youssef A Ghoneim

William C Lin

Aleksander Boguslaw Hac

David M Sidlosky

Stephen R Pastor

Michael Douglas Rizzo

Ronald Paul

Ashok Chandy

Michael Paul Turski

Douglass L Carson

Duane Edward Bassett

Karen Ann Boswell

John F Hoying

Alan J Lee

John D Martens

Howard Hans Ludwig

Hong Xing Hu

Edmund Stanley Browalski

Vivek Jaikamal

Joachim Busshardt

Mutasim Abdurrahman Salman

Kevin Austin O'Dea

David John Barta

Kamal N Majeed

Steven L Tracht

William Chin-Woei Lin

Steven Paul Loudon

Eldon Gerrald Leaphart

Michael John Check

John E Dickinson

Brian P McDonald

Scott D Morrison

Todd David Brown

Chester W Gryczan

Rowland Curl Augustus

Sean Padraig O'Connell

A control system manages yaw-plane motion, while simultaneously comprehending and managing roll motion. The system reduces excessive maneuver-induced roll motion by properly shaping yaw-plane motion, which may include increasing yaw damping and/or decreasing a yaw gain, under various conditions, to avoid excessive excitation of roll dynamics.

Motor vehicle control using a dynamic feedforward approach

A method for automatically adjusting a vehicle stability enhancement (VSE) system is disclosed. The VSE system is used in conjunction with a steering system having a plurality of driver-selectable steering modes associated therewith. In an exemplary embodiment, the method includes configuring a reference model within the VSE system to generate desired vehicle handling aspects, the desired vehicle handling aspects being a function of one or more driver inputs to the steering system. Then, a determination is made as to which of the plurality of driver-selectable steering modes is activated, wherein each of the desired vehicle handling aspects generated is made further dependent upon a specific steering mode selected.

Method for automatically adjusting reference models in vehicle stability enhancement (VSE) systems

A control system for a steering system in a vehicle comprising: a reference model responsive to an operator input that computes desired states of the vehicle; a feedforward controller in operable communication with the reference model. The feedforward controller computes a first control value based on input from said reference model and based on at least one of: a lateral velocity, a rate of lateral velocity, a lateral acceleration, and a combination, wherein the combination includes a yaw rate with at least one of a lateral velocity, a rate of lateral velocity, and a lateral acceleration of the motor vehicle. The system also includes an actuator for affecting the steering system based on the first control value, the actuator in operable communication with the feedforward controller.

Active steering for handling/stability enhancement

A vehicle chassis control stores first and second calibrated values of a predetermined braking parameter and a steering correction parameter. The control includes apparatus for detecting a split coefficient condition with respect to the road surface; and, when it does and a braking signal is present, the control actuates braking apparatus for a wheel on the side of the vehicle having the higher coefficient of friction with the first calibrated value of the predetermined braking parameter and simultaneously actuates the steering apparatus with a steering correction to compensate for yaw induced by braking on the split coefficient road surface. If the steering correction is not available, however, the braking apparatus is actuated for the wheel having the higher coefficient of friction with the second calibrated value of the predetermined braking parameter without simultaneously actuating the steering apparatus with the steering correction. The steering correction may have an open loop part derived from a difference between wheel slips of two wheels on opposite sides of the vehicle and/or a closed loop part derived from yaw rate, side slip and/or side slip rate error.

Vehicle chassis control with coordinated brake and steering control on split coefficient surface

A method for automatically adjusting a vehicle stability enhancement (VSE) system. The VSE system is used in conjunction with a steering system having a plurality of driver-selectable steering modes associated therewith. The method includes configuring a reference model within the VSE system to generate desired vehicle handling aspects, the desired vehicle handling aspects being a function of one or more driver inputs to the steering system. Then, a determination is made as to which of the plurality of driver-selectable steering modes is activated, wherein each of the desired vehicle handling aspects generated is made further dependent upon a specific steering mode selected, and wherein the desired vehicle handling aspects include a desired steady state yaw rate; and the one or more driver inputs includes an effective road wheel position.

A rear steer control for a motor vehicle considers vehicle velocity in three ranges and provides an out of phase rear steer angle in open loop control within a low velocity range for oversteer assistance of parking and similar vehicle maneuvers, an in phase rear steer angle in closed loop control responsive to vehicle yaw rate within a high velocity range for understeer vehicle stability assistance, and a steer angle in closed loop control responsive to vehicle yaw rate within an intermediate velocity range. In a preferred embodiment, the closed loop control in the high velocity range may be combined with an open loop control. The control further provides supplemental throttle adjustments in coordination with the rear steer control for increased traction and stability in a turn.

Motor vehicle with supplemental rear steering having open and closed loop modes

A control system for a motor vehicle subsystem comprises a reference model and a feedforward controller. The reference model computes desired states of the subsystem. The feedforward controller computes a first control value based on input from the reference model, and computes a second control value based on yaw rate of the vehicle and a control variable for the subsystem.

System and method incorporating dynamic feedforward for integrated control of motor vehicle steering and braking

An integrated active steering and braking control system for providing one or more corrective yaw moments to a vehicle in response to a plurality of signals indicative of operational and environmental conditions related to the vehicle is disclosed. The system comprises a reference model, an estimator, a vehicle level brake/steer controller, and an actuator controller. The reference model provides a feedforward front steering angle correction signal a feedforward rear steering angle correction signal, a desired yaw rate signal, a desired lateral velocity signal, and a desired side slip angle signal. The estimator provides an estimated surface coefficient of adhesion signal, an estimated lateral velocity signal, and an estimated side slip angle signal. In response to the signals from the reference model and the estimator, the vehicle level brake/steer controller provides either a desired speed differential signal, a desired front steering angle signal and/or a desired rear steering angle signal. The actuator controller selectively provides a corrective braking signal to a brake actuator, a corrective front steering signal to a steering actuator, and a corrective rear steering signal to the steering actuator as a function of the desired speed differential signal, the desired front steering angle signal, and the desired rear steering angle signal, respectively.

Integrated control of active tire steer and brakes

A brake system control for use in a vehicle with four wheels comprising the steps of: determining a desired yaw rate (,); determining a yaw torque command responsive to the desired yaw rate (,); if the vehicle is in an anti-lock braking mode during driver commanded braking, applying the yaw torque command to only one of the four wheels to release brake pressure in said one of the four wheels (,); if the vehicle is in a positive acceleration traction control mode during driver commanded acceleration, applying the yaw torque command to only one of the four wheels to apply brake pressure in said one of the four wheels (,); and if the vehicle is not in the anti-lock braking mode or in the positive acceleration traction control mode, then: (i) determining whether a vehicle brake pedal is depressed (,); (ii) if the vehicle brake pedal is depressed, applying brake force to the vehicle wheels responsive to the depression of the brake pedal (,), wherein the applied brake force is modified to at least two of the vehicle wheels to create a left-right brake torque differential responsive to the yaw torque command.

Brake control system

An improved closed-loop vehicle yaw control in which a yaw rate limit based on measured lateral acceleration is used during transient steering maneuvers to dynamically limit a desired yaw rate derived from driver steering input. A preliminary yaw rate limit is computed based on the measured lateral acceleration, and a dynamic yaw rate limit having a proper phase relationship with the desired yaw rate is developed based on the relative magnitudes of the desired yaw rate and the preliminary yaw rate limit. A two-stage process is used to develop the dynamic yaw rate limit. A first stage yaw rate limit is determined according the lower in magnitude of the desired yaw rate and the preliminary yaw rate limit, and a second stage yaw rate limit (i.e., the dynamic yaw rate limit) is determined according to the relative magnitudes of (1) the desired yaw rate and the second stage yaw rate limit, and (2) the first stage yaw rate limit and the second stage yaw rate limit. The desired yaw rate, as limited by the dynamic yaw rate limit, is then combined with the actual or estimated yaw rate to form a yaw rate error, which in turn, is used to develop a yaw rate control command for the vehicle.

Vehicle yaw rate control with yaw rate command limiting

A brake system control method, comprising the steps of: determining a maximum acceleration of a vehicle on a high coefficient of adhesion road surface; measuring an acceleration of the vehicle; determining a ratio between the measured acceleration of the vehicle and the maximum acceleration of the vehicle on the high coefficient of adhesion road surface; responsive to the ratio, determining a signal indicative of present coefficient of adhesion; determining a brake actuator command responsive to the signal; and providing the brake actuator command to a brake actuator, wherein an accurate estimation of coefficient of friction between the vehicle wheels and the road surface is used in the brake system control.

Brake system control method responsive to measured vehicle acceleration

A brake system control method, comprising the steps of: measuring a longitudinal speed and steering angle of the vehicle; specifying an un-damped natural frequency and a damping ratio for a linear reference model of said vehicle; determining a first gain parameter relating a desired value of steady state lateral velocity to the vehicle steering angle; computing a desired lateral velocity as a function of said first gain parameter, the measured longitudinal speed, the measured steering angle, and the specified un-damped natural frequency and damping ratio; determining a second gain parameter relating a desired value of steady state yaw rate to the vehicle steering angle; computing a desired yaw rate as a function of said second gain parameter, the measured longitudinal speed and steering angle, and the specified un-damped natural frequency and damping ratio; measuring a lateral acceleration and yaw rate of said vehicle, and forming a yaw rate command for said vehicle based at least part in a first deviation between said desired and measured yaw rates, and a second deviation between said measured lateral acceleration and a desired lateral acceleration based on said desired lateral velocity; and differentially braking wheels of said vehicle to impart a yaw moment corresponding to said yaw rate command.

Brake system control

A brake system control for use in a vehicle with wheels, wheel brakes and a body, comprising the steps of: measuring a plurality of vehicle parameters; responsive to the measured parameters, determining at least a vehicle yaw rate, a vehicle slip angle, a desired yaw rate and a desired slip angle; responsive to the measured parameters, estimating a coefficient of adhesion between the vehicle wheels and a road surface; implementing a control responsive to the vehicle yaw rate and the desired yaw rate with a first authority and responsive to the vehicle slip angle and the desired slip angle with a second authority, wherein the first authority increases as the estimated coefficient of adhesion increases and decreases as the estimated coefficient of adhesion decreases; and controlling the wheel brakes responsive to the control to reduce a first difference between the vehicle yaw rate and the desired yaw rate and to reduce a second difference between the vehicle slip angle and the desired slip angle.

Brake system control method employing yaw rate and ship angle control

In a vehicle with a first operating mode in which all vehicle wheels have substantially no lateral movement on a road surface and a second operating mode in which at least some of the vehicle wheels have lateral movement on the road surface, and with an actuator capable of affecting vehicle yaw rate, a vehicle yaw rate control method comprising the steps of: measuring an actual vehicle yaw rate; measuring vehicle steering wheel position; in the second mode of operation, determining a desired yaw rate command linearly responsive to the measured steering wheel position; wherein the actuator is controlled to minimize a difference between the measured vehicle yaw rate and the desired vehicle yaw rate.

Chassis control system

A vehicle chassis system control method, comprising the steps of: measuring vehicle yaw rate, vehicle speed, and vehicle lateral acceleration; determining, responsive to the yaw rate, vehicle speed and lateral acceleration, an index ratio; comparing the index ratio to a predetermined threshold indicating a limit above which active chassis control is not desired; and responsive to the comparison, setting a signal indicating termination of active chassis control if the index ratio is above the predetermined threshold.

Growing community of inventors

Troy, MI, United States of America

Hsien Heng Chen