Abstract: A method of estimating friction in a steering system controlled by a control module is provided. The method includes performing by the control module, estimating a steering load gain; estimating a steering load hysteresis; and determining friction based on the steering load gain, the steering load hysteresis, and a reference model.

Abstract: Systems and methods for controlling a vehicle steering system are provided. In one exemplary embodiment, the method includes receiving a desired front road wheel angle signal at a controller. The desired front road wheel angle signal is indicative of a desired front road wheel angle of vehicle wheels. The method further includes receiving a parking assist request signal at the controller indicating a parking assist operational mode is desired. The method further includes generating a desired motor torque signal for controlling a power steering motor in the parking assist operational mode utilizing the controller, based on the desired front road wheel angle signal and the parking assist request signal.

Abstract: Systems and methods for controlling a vehicle steering system are provided. In one exemplary embodiment, the method includes receiving a desired front road wheel angle signal at a controller. The desired front road wheel angle signal is indicative of a desired front road wheel angle of vehicle wheels. The method further includes receiving a parking assist request signal at the controller indicating a parking assist operational mode is desired. The method further includes generating a desired motor torque signal for controlling a power steering motor in the parking assist operational mode utilizing the controller, based on the desired front road wheel angle signal and the parking assist request signal.

Abstract: Systems and methods for determining an absolute rotational position of the vehicle handwheel are provided. In one exemplary embodiment, a method includes determining a slope value based on the delta torque value associated with the vehicle steering system and the delta rotational position value associated with a vehicle handwheel. The method further includes setting an absolute position value indicating the absolute position of the vehicle handwheel equal to a predetermined steering travel limit of the vehicle handwheel when the slope value is within a predetermined slope range.

Abstract: Systems and methods for controlling a vehicle steering system are provided. In one exemplary embodiment, the method includes receiving a desired front road wheel angle signal at a controller. The desired front road wheel angle signal is indicative of a desired front road wheel angle of vehicle wheels. The method further includes receiving a parking assist request signal at the controller indicating a parking assist operational mode is desired. The method further includes generating a desired motor torque signal for controlling a power steering motor in the parking assist operational mode utilizing the controller, based on the desired front road wheel angle signal and the parking assist request signal.

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: An all wheel steering system for a vehicle comprising a controller having a first input for receiving a signal from a hand wheel position sensor, a second input for receiving a signal from a vehicle speed sensor, and a third input for receiving a signal that varies depending upon whether a trailer is hitched the vehicle. The controller generates an output for controlling a rear wheel steering actuator. The output varies as a function of the first, second, and third inputs such that when a trailer is hitched to the vehicle the out-of-phase rear steer amount at low speeds is reduced and the in-phase rear steering amount at high speeds is increased.

Abstract: The above discussed and other drawbacks and deficiencies of the prior art are overcome or alleviated by an all-wheel steering system for a vehicle comprising a controller having a first input for receiving a signal from a hand wheel position sensor, a second input for receiving a signal from a vehicle speed sensor, and a third input for receiving a signal that varies depending upon whether a trailer is hitched to said vehicle. The controller generates an output for controlling a rear wheel steering actuator. The output varies as a function of the first, second, and third inputs such that when a trailer is hitched to said vehicle the out-of-phase rear steer amount at low speeds is reduced and the in-phase rear steering amount at high speeds is increased.

Abstract: A method for detecting a loss of motor control in an electric power steering system is disclosed. In an exemplary embodiment, the method includes determining a duty cycle of a steering command signal generated by a controller. The steering command signal commands a steering mechanism to be turned in either a first or a second direction, the second direction being opposite to the first direction. A steering velocity of the steering mechanism is determined, the steering velocity being characterized by a steering velocity magnitude and a steering velocity direction whenever the steering velocity is greater than zero. The steering velocity direction corresponds to either the first or the second direction. The duty cycle is then compared to a first selected value, and the steering velocity magnitude is compared to a second selected value.

Abstract: A method for detecting a loss of motor control in an electric power steering system is disclosed. In an exemplary embodiment, the method includes determining a duty cycle of a steering command signal generated by a controller. The steering command signal commands a steering mechanism to be turned in either a first or a second direction, the second direction being opposite to the first direction. A steering velocity of the steering mechanism is determined, the steering velocity being characterized by a steering velocity magnitude and a steering velocity direction whenever the steering velocity is greater than zero. The steering velocity direction corresponds to either the first or the second direction. The duty cycle is then compared to a first selected value, and the steering velocity magnitude is compared to a second selected value.