摘要:
Methods and systems are provided for determining a desired yaw rate for a vehicle. The vehicle has a plurality of handling states and comprises a yaw rate sensor for determining an actual yaw rate. The method comprises selecting one of the plurality of handling states, determining the desired yaw rate for the vehicle based on the road wheel angle, the velocity, and the selected one of the plurality of handling states, and activating one or more vehicle stability control measures if the difference between the desired yaw rate and the actual yaw rate for the vehicle exceeds a predetermined threshold.
摘要:
A method is provided for estimating vehicle velocity for a vehicle using a single-antenna global positioning system (GPS). An absolute speed and a course angle of the vehicle is measured using the single-antenna GPS. The yaw rates of the vehicle are measured independently of the GPS. An integrated yaw rate of the vehicle is calculated as a function of the measured yaw rates over a period of time. A yaw angle is determined as a function of a reference yaw angle and the integrated yaw rate. Aside slip angle is calculated as a function of the estimated yaw angle and the course angle provided by the GPS. The vehicle velocity is determined as a function of the absolute speed and the side slip angle. The vehicle velocity is provided to a vehicle dynamic control application.
摘要:
An exemplary method for controlling torque at one or more wheels of a vehicle, including controlling both positive torque (acceleration) and negative torque (braking) with a single torque command. According to one embodiment, the method interprets the acceleration and braking intent of the driver, takes into consideration certain special conditions (e.g., vehicle dynamic conditions like wheel slip, over- and under-steer, etc.), and generates one or more individual torque commands that are sent to individual wheels or corners of the vehicle. The individual torque commands may address certain chassis and powertrain functions like acceleration and braking, and may provide full-feature torque control (i.e., acceleration, braking, vehicle dynamics, etc.) on an individual wheel basis. It is also possible for the method to be used in a system where a number of the common chassis, powertrain and/or vehicle dynamic modules have been integrated into a single torque control module or the like.
摘要:
A controller of an active rear steering (ARS) control system includes a processor and a software module. The software module includes instructions that, when executed by the processor, cause the processor to determine rear steering angles, determine a vehicle state, determine shaping functions, and determine a rear steering command.
摘要:
A system and method for estimating vehicle lateral velocity that defines a relationship between front and rear axle lateral forces and front and rear axle side-slip angles. The method includes providing measurements of vehicle yaw-rate, lateral acceleration, longitudinal speed, and steering angle. The method also includes using these measurements to provide a measurement of the front and rear axle forces. The method calculates a front axle lateral velocity and a rear axle lateral velocity, and calculates a front axle side-slip angle based on the rear axle lateral velocity and a rear axle side-slip angle based on the front axle lateral velocity. The method then estimates front and rear axle forces, and selects a virtual lateral velocity that minimizes an error between the estimated and measured lateral axle forces. The method then provides an estimated vehicle lateral velocity using the selected virtual lateral velocity.
摘要:
A system and method for ABS stability control is provided, the method comprising the steps of determining whether a first wheel is in an ABS mode; determining whether the first wheel is in an apply mode; determining whether a second parallel wheel is in the release mode; calculating an adjusted wheel slip if the first wheel is in the ABS mode, the first wheel is in the apply mode, and the second parallel wheel is in the release mode; and determining a control mode for the first wheel using the adjusted wheel slip.
摘要:
A system and method of vehicle stability enhancement control during ABS operation, the method comprising the steps of determining whether ABS mode is active; determining whether VSE is required; calculating a target wheel speed for each wheel if ABS mode is active and VSE is required; calculating an adjusted wheel slip for each wheel by subtracting the wheel speed for each wheel from the target wheel speed for each wheel and dividing the difference by the target wheel speed for each wheel; and determining an ABS control mode for each wheel using the adjusted wheel slip. The method further provides the step of calculating the target wheel speed for each wheel, in which the step of calculating the target wheel speed for each wheel further comprises adding a VSE modification term for each wheel to the vehicle speed to calculate the target wheel speed.
摘要:
An exemplary engine control system and method for controlling a vehicle engine during certain shifting maneuvers that involve a manual transmission, such as a ‘no-lift upshift’ where the driver does not release the accelerator pedal during manual shifting. The engine control method may be used to temporarily control the vehicle engine during a no-lift upshift maneuver so that the engine performs well without reaching excessively high engine speeds that could result in vehicle instability or damage. The engine control method described herein may be used with other performance driving maneuvers and techniques as well, such as a power shift maneuvers, etc.
摘要:
A system and method for controlling a vehicle engine during one or more performance driving events, such as a performance takeoff, shifting or cornering event. The engine control system may be used to maintain stability when the vehicle is being driven in a competitive or aggressive fashion by temporarily controlling the vehicle engine through the manipulation of engine torque, engine speed or some other means. If the engine control system receives competing command signals from different vehicle subsystems, then the system may arbitrate or otherwise manage the competing command signals so that different subsystems can function together properly. In one embodiment, the engine control system blends the commands signals from two or more subsystems.
摘要:
A system and method for estimating surface coefficient of friction in a vehicle system. The method includes providing a kinematics relationship between vehicle yaw-rate, vehicle speed, vehicle steering angle and vehicle front and rear axle side-slip angles that is accurate for all surface coefficient of frictions on which the vehicle may be traveling. The method defines a nonlinear function for the front and rear axle side-slip angles relating to front and rear lateral forces and coefficient of friction, and uses the nonlinear function in the kinematics relationship. The method also provides a linear relationship of the front and rear axle side-slip angles and the front and rear lateral forces using the kinematics relationship. The method determines that the vehicle dynamics have become nonlinear using the linear relationship and then estimates the surface coefficient of friction when the vehicle dynamics are nonlinear.