Abstract: An automated and algorithmic method utilizing motor vehicle steering geometry knowledge, applicable to small and large turn angles, along with knowledge of motor vehicle understeer gradient, for determining motor vehicle yaw gain by which a motor vehicle yaw gain table is populated for use by an electronic stability control system of the motor vehicle. The method may utilize either a recursive methodology of population or an open loop methodology of population.

Abstract: A method for calculating a yaw gain for use in controlling a vehicle includes the steps of obtaining a steer angle of the vehicle, obtaining a vehicle speed, determining an adjustment factor for a baseline steering geometry equation, obtaining vehicle understeer gradient as a function of lateral acceleration, and calculating the yaw gain. The adjustment factor is determined based at least in part on the turn radius. The yaw gain is calculated based at least in part on the vehicle speed, the steer angle, the vehicle understeer gradient, and the adjustment factor.

Abstract: A vehicle includes a plurality of sub-systems and corresponding controllers for effecting normal control thereover. The vehicle further includes a vehicle dynamics controller for providing high-priority sub-system commands for sub-system control to effect vehicle dynamics enhancements. The vehicle dynamics controller includes a plurality of independently decomposable and recomposable software components or layers and accessible inter-layer bus structure.

Abstract: A method for operating a vehicle electronic stability control (“ESC”) system utilizing values for a variable obtained from a primary source and a redundant source includes the steps of receiving a first value for the variable from the primary source, receiving a second value for the variable from the redundant source, generating a normalized value as a function of the first value and the second value, determining whether the primary source is operating correctly, utilizing the first value for operation of the vehicle ESC system if the primary source is operating correctly, and utilizing the second value for operation of the vehicle ESC system if the primary source is not operating correctly and the second value is not greater in absolute value than the normalized value.

Abstract: A system and method that warn a vehicle driver by shaking or dithering the steering wheel that one or more active control systems on the vehicle is providing active control. The system includes an AFS actuator for providing a steering assist signal for stability control purposes, and a VES actuator for providing resistance against turning of the steering wheel. The system also includes a controller for causing the AFS actuator to shake the steering wheel if the active control is active and for causing the VES controller to apply and release tension to the steering wheel if the steering wheel is turned and the active control is active. The controller may increase the shaking of the steering wheel as the amount of the active control increases.

Abstract: A system and method that warn a vehicle driver by shaking or dithering the steering wheel that one or more active control systems on the vehicle is providing active control. The system includes an AFS actuator for providing a steering assist signal for stability control purposes, and a VES actuator for providing resistance against turning of the steering wheel. The system also includes a controller for causing the AFS actuator to shake the steering wheel if the active control is active and for causing the VES controller to apply and release tension to the steering wheel if the steering wheel is turned and the active control is active. The controller may increase the shaking of the steering wheel as the amount of the active control increases.

Abstract: Before braking occurs the speed of non-driven wheels is monitored and averaged to determine vehicle speed and an integrator is initialized with that speed. Acceleration is periodically calculated from the vehicle speed, stored in a ring buffer and averaged. The output of a chassis accelerometer is also sampled during the same periods and stored in a similar ring buffer and averaged. Accelerometer bias due to slope or drift is determined as the difference of the two averaged accelerations. The noise level of the accelerometer bias is determined by filtering and rectification. After braking occurs, the accelerometer output is corrected by subtracting the bias and the noise and is then used to continuously update the integrator output to provide an estimate of vehicle speed during braking.

Abstract: An improved method of controlling an electro-hydraulic control system by developing a motor control command in relation to the desired force to be exerted by an electric motor on a mechanical element whose displacement determines the hydraulic pressure. The control command is comprised of two magnitude signals. The first magnitude signal must be sufficient to exert enough force to overcome a static friction characteristic of the mechanical element, and the second magnitude signal is selected to achieve a desired average current or voltage over that control period. The time constant for the control command is less than the mechanical time constant of the system, but greater than the the electrical time constant of the system. The control command may be implemented by using either current or voltage control.

Abstract: A method and apparatus are disclosed for analyzing the dynamic resistance of a resistance spot welding process to determine the time of an expulsion event and use that time as the weld completion time for controlling weld termination via a weld feedback signal, controlling automatic current stepping, and identifying maintenance needs. A preconditioning pulse is used to stabilize the weld process and aid in obtaining interpretable resistance information. After an initial blanking period the resistance curve is analyzed by calculating first and second derivative values and applying several algorithms that make possible the computer recognition of characteristic resistance curve shapes resulting from weld expulsion under good geometry, bad geometry and edge weld conditions.