Abstract: A system is provided for enhancing inertial sensing within a vehicle. The system determines measured rotational rates and translational accelerations of the vehicle using an inertial measurement unit. In addition, the system also determines estimated rotational rates and translational accelerations of the vehicle based on a remote sensing system. The system generates compensated rotational rates and translational accelerations to reduce gain errors or offset errors of the inertial measurement unit based on the estimated rotational rates and translational accelerations.

Abstract: A system is provided for enhancing inertial sensing within a vehicle. The system determines measured rotational rates and translational accelerations of the vehicle using an inertial measurement unit. In addition, the system also determines estimated rotational rates and translational accelerations of the vehicle based on a remote sensing system. The system generates compensated rotational rates and translational accelerations to reduce gain errors or offset errors of the inertial measurement unit based on the estimated rotational rates and translational accelerations.

Abstract: A method, system, and computer program product for calculating a torque overlay command in a steering control system is provided. The method includes receiving a current hand wheel angle, receiving a change in vehicle yaw moment command, and calculating a lateral force in response to the change in vehicle yaw moment command. The method also includes determining a new tire side slip angle from the lateral force and calculating a commanded hand wheel angle from the new tire side slip angle. The method further includes calculating an error signal as a difference between the commanded hand wheel angle and the current hand wheel angle, and generating a torque overlay command from the error signal.

Abstract: A method, system, and computer program product for tire slip angle limiting in a steering control system for a vehicle are provided. The method includes calculating a first steering augmentation angle from a vehicle speed and a handwheel angle. The method further includes calculating an upper bound angle limit and a lower bound angle limit as functions of a vehicle slip angle and a tire slip angle limit. The method also includes bounding the sum of the handwheel angle plus the first steering augmentation angle between the upper bound angle limit and the lower bound angle limit to produce a first bounded angle. The method additionally includes subtracting the sum of the handwheel angle plus the first steering augmentation angle from the first bounded angle to produce a first limiting function, and producing a motor angle command by adding the first limiting function plus the first steering augmentation angle.

Abstract: A technique for reducing excessive motor vehicle roll angle using a feedforward control comprises a number of steps. Initially, a steering angle and a speed of the-motor vehicle are determined. Next, a lateral acceleration of the vehicle is estimated based on the steering angle and the speed. Then, a lateral acceleration proportional and derivative (PD) term of the estimated lateral acceleration is determined and roll angle reduction is implemented when the lateral acceleration PD term exceeds a first threshold. The roll angle reduction may be achieved through application of a braking force to an outside front wheel of the vehicle. A magnitude of the braking force may be proportional to a difference between the lateral acceleration PD term and the first threshold.

Abstract: A method, system, and computer program product for calculating a torque overlay command in a steering control system is provided. The method includes receiving a current hand wheel angle, receiving a change in vehicle yaw moment command, and calculating a lateral force in response to the change in vehicle yaw moment command. The method also includes determining a new tire side slip angle from the lateral force and calculating a commanded hand wheel angle from the new tire side slip angle. The method further includes calculating an error signal as a difference between the commanded hand wheel angle and the current hand wheel angle, and generating a torque overlay command from the error signal.

Abstract: A method, system, and computer program product for tire slip angle limiting in a steering control system for a vehicle are provided. The method includes calculating a first steering augmentation angle from a vehicle speed and a handwheel angle. The method further includes calculating an upper bound angle limit and a lower bound angle limit as functions of a vehicle slip angle and a tire slip angle limit. The method also includes bounding the sum of the handwheel angle plus the first steering augmentation angle between the upper bound angle limit and the lower bound angle limit to produce a first bounded angle. The method additionally includes subtracting the sum of the handwheel angle plus the first steering augmentation angle from the first bounded angle to produce a first limiting function, and producing a motor angle command by adding the first limiting function plus the first steering augmentation angle.

Abstract: 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.

Abstract: A method for implementing a vehicle stability enhancement (VSE) system for a vehicle is disclosed. In an exemplary embodiment, the method includes receiving a handwheel angle input and adjusting the handwheel angle input in response to a variable steering ratio generated in the vehicle. The adjusted handwheel angle input is inputted into a reference model, the reference model thereby outputting one or more desired vehicle handling aspects.

Abstract: 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.

Abstract: Disclosed herein in an exemplary embodiment is a method for providing variable assist in an active steering system of a vehicle. The method comprises: receiving an input signal that includes at least one of, a variable ratio command signal, a stability command signal, a hand wheel position signal, a vehicle speed signal indicative of a speed of the vehicle, a signal indicative of an operator selected function, and a signal indicative a vehicle operating mode. The method also comprises: generating an assist command to an assist mechanism responsive to the input signal wherein the assist mechanism is operatively coupled to the differential actuator and a road wheel of the steering system to provide an assist torque responsive to the motion of the output shaft. The active steering system includes a hand wheel operatively coupled to an input of a differential actuator and a motor operatively coupled to the differential actuator.

Abstract: A method for implementing a vehicle stability enhancement (VSE) system for a vehicle is disclosed. In an exemplary embodiment, the method includes receiving a handwheel angle input and adjusting the handwheel angle input in response to a variable steering ratio generated in the vehicle. The adjusted handwheel angle input is inputted into a reference model, the reference model thereby outputting one or more desired vehicle handling aspects.

Abstract: 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.

Abstract: 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.

Abstract: 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.