Abstract: Methods and systems are provided for controlling a steering system of a vehicle is provided. A detection unit is configured to obtain a compass heading, a global positioning system (GPS) heading, or both. A processor is coupled to the detection unit, and is configured to determine whether a vehicle is on a straight line path using the compass heading, the GPS heading, or both, and to selectively implement a feature of the steering system based on whether it is determined that the vehicle is not on a straight line path.

Abstract: A system and method for determining whether a driver is holding a vehicle steering wheel. The vehicle will include an electric power steering system and may further include autonomous or semi-autonomous driving features, such as Lane Centering Control or Lane Keeping Assist. The system includes a passive detection technique which monitors steering torque and steering angle, determines a resonant frequency of oscillation of the steering system from the measured data, and compares the resonant frequency to a known steering system natural frequency to make a hands-on/off determination. If the passive technique results are below a confidence threshold, then an active technique is employed which provides a steering angle perturbation and measures the frequency response, where the perturbation signal has characteristics which are prescribed based on the results of the passive technique. A steering torque greater than a threshold value is also an indication of the driver holding the steering wheel.

Abstract: A hydraulic mount apparatus includes a housing defining a cavity. The apparatus also includes an annular member disposed in the cavity. The annular member is secured to the housing to split the cavity into a first chamber and a second chamber. The apparatus further includes a pressure relief apparatus coupled to the housing. The pressure relief apparatus is configured to allow fluid communication between the first and second chambers in response to a predetermined pressure threshold being reached in at least one of the first and second chambers. A suspension system including a shock absorber and a link is coupled to the shock absorber. The suspension system further includes the hydraulic mount apparatus coupled to one of the shock absorber and the link.

Abstract: A method of controlling a tire/wheel assembly includes measuring a first amplitude of a selected harmonic order of the radial force variation of the assembly, and locating a first angular location of the selected order of the radial force variation of the assembly. A second angular location of a tire is located, which indicates a phase of the selected order of a radial force variation of the tire, having a second amplitude. A third angular location of a wheel is located, which indicates a phase of the selected order of a runout value of the wheel, and has a third amplitude. A remaining force metric may be calculated using the pairs of the first amplitude and the first angular location, the second amplitude and the second angular location, and the third amplitude and the third angular location.

Abstract: A method for evaluating a vehicle tire is provided. The method obtains, by at least one vehicle onboard motion sensor, vibration data associated with a corner of a vehicle, the vehicle tire being located at the corner; detects an inflation pressure value for the vehicle tire; receives, from a vehicle onboard computer system, tire age data associated with the vehicle tire; calculates remaining tread groove depth for the vehicle tire, based on the vibration data, the inflation pressure data, and the tire age data; and performs a task, based on the remaining tread groove depth for the vehicle tire, wherein the task comprises at least one of: presenting a notification of the remaining tread groove depth to a driver, and setting a code onboard the vehicle, wherein the code is associated with service notifications.

Abstract: A method for testing a vehicle includes designing a tire that has a runout as a function of an angular position of the tire that induces a desired vibration in a vehicle when the tire operates on the vehicle. The method also includes performing a test on the vehicle while operating the vehicle with the tire having the design that induces a desired vibration in a vehicle.

Abstract: Methods and apparatus are provided for determining steering performance. The method includes coupling at least one load source to the steering system, and coupling a portion of the steering system to an angle input source. The method also includes outputting one or more control signals by a processor to the at least one load source to apply a load to the steering system and outputting one or more control signals by the processor to the angle input source to apply an input to the steering system. The method includes receiving torque data indicating a performance of the steering system based on the load applied to the steering system by the at least one load source and the input applied by the angle input source.

Abstract: A method and system for determining whether a driver of a vehicle is in contact with a steering wheel of the vehicle is provided. One embodiment of the method includes the steps of generating a perturbation signal that causes vibration of the steering wheel and receiving a steering signal from a steering system sensor configured to provide an indication of at least one of a steering torque and a steering movement of a component of an electronic power steering system of the vehicle. The method further includes the steps of mixing the perturbation signal and the steering signal to produce a heterodyne signal and generating a driver contact signal indicative of whether the driver of the vehicle is in contact with the steering wheel of the vehicle, the value of the driver contact signal dependent on characteristics of the heterodyne signal relating to the perturbation signal.

Abstract: Methods and systems are provided for evaluating a steering system of a vehicle, in which the steering system includes a steering column, steering rack, and pinion. The rack is manipulated as the steering system is mounted to a testing system. The steering column is also manipulated as the steering system is mounted to the testing system. Data is collected from the manipulating of the rack and the dithering of the steering column for use in evaluating the steering system.

Abstract: A system and method for determining whether a driver is holding a vehicle steering wheel. The vehicle will include an electric power steering system and may further include autonomous or semi-autonomous driving features, such as Lane Centering Control or Lane Keeping Assist. The system includes a passive detection technique which monitors steering torque and steering angle, determines a resonant frequency of oscillation of the steering system from the measured data, and compares the resonant frequency to a known steering system natural frequency to make a hands-on/off determination. If the passive technique results are below a confidence threshold, then an active technique is employed which provides a steering angle perturbation and measures the frequency response, where the perturbation signal has characteristics which are prescribed based on the results of the passive technique. A steering torque greater than a threshold value is also an indication of the driver holding the steering wheel.

Abstract: Methods and apparatus are provided for determining steering performance. The method includes coupling at least one load source to the steering system, and coupling a portion of the steering system to an angle input source. The method also includes outputting one or more control signals by a processor to the at least one load source to apply a load to the steering system and outputting one or more control signals by the processor to the angle input source to apply an input to the steering system. The method includes receiving torque data indicating a performance of the steering system based on the load applied to the steering system by the at least one load source and the input applied by the angle input source.

Abstract: Methods, system and apparatus are provided for reducing steering wheel vibrations (SWVs). At least one heterodyning operation is performed during the generation of a gain-and-phase-compensated motor drive command signal. The gain-and-phase-compensated motor drive command signal is generated at a particular angular frequency, based on an angular velocity and an angular position of a wheel. The gain-and-phase-compensated motor drive command signal is communicated to an electric power steering system to control motor torque to reduce periodic content in a periodic electrical torque signal at the particular angular frequency.

Abstract: Methods and systems are provided for determining frequencies associated with tire crown bending. The system includes a vibration generating device configured to excite vibrations through a tire. The system further includes a vibration sensing arrangement configured to sense vibrations at a plurality of sensing points on the tire. A computer is in communication with the vibration sensing arrangement and configured to determine a first frequency associated with bending of the crown of the tire based at least partially on phase differences between the sensed vibrations at the plurality of points on the tire.

Abstract: A method is provided for controlling a motor drive torque in an EPS system having a motor and a steering assembly. The method includes receiving a torque signal from the steering assembly; processing the torque signal in accordance with a steering perception program to produce a motor control signal; and controlling the motor drive torque based on the motor control signal.

Abstract: A system for characterizing a vehicle tire is provided. The system includes a testing assembly configured to support the vehicle tire. The assembly includes a force-moment transducer configured to gather force information from the vehicle tire in response to a stimulus on the vehicle tire. The system further includes an accelerometer coupled to the vehicle tire and configured to gather vibration information from the vehicle tire in response to the stimulus on the vehicle tire. The system further includes a post-processing system configured to receive the vibration information from the accelerometer and the force information from the force-moment transducer. The post-processing system is further configured to extract resonant frequencies from the vibration information and the force information.

Abstract: Methods and systems are provided for suppression of steering wheel vibrations generated by periodic disturbances in a vehicle steering system. An exemplary method reducing steering wheel vibrations caused by periodic disturbances involves determining a gross torque attributable to the periodic disturbances in the steering system, identifying a desired amount of suppression of the vibrations at the steering wheel, determining an offset torque based on the gross torque and the desired amount of suppression, and generating a motor command signal in a manner that is influenced by the offset torque. The motor drive command signal is provided to an electric motor coupled the steering wheel and/or the vehicle tires, and the motor drive command signal influences the torque applied by the motor to assist steering of the vehicle tires by the steering wheel in a manner that attenuates the vibrations communicated to the steering wheel by the desired amount.

Abstract: Methods and systems are provided for controlling a steering system of a vehicle is provided. A detection unit is configured to obtain a compass heading, a global positioning system (GPS) heading, or both. A processor is coupled to the detection unit, and is configured to determine whether a vehicle is on a straight line path using the compass heading, the GPS heading, or both, and to selectively implement a feature of the steering system based on whether it is determined that the vehicle is not on a straight line path.

Abstract: Methods and systems are provided for controlling an electric power steering system. In one embodiment, a method includes: storing a compensation table having compensation values that are associated with motor torque drive values; receiving a current motor torque drive signal; determining a compensation action the current motor torque drive signal; determining a compensation value based on the compensation action and the table; and generating a motor torque drive signal based on the compensation value.

Abstract: Methods and systems are provided for controlling a steering system of a vehicle is provided. A detection unit is configured to obtain one or more of the following values: a compass heading, a global positioning system (GPS) heading, a yaw velocity, and a difference in tire angular velocities. A processor is coupled to the detection unit, and is configured to determine whether a vehicle is on a straight line path using one or more of the compass heading, the GPS heading, the yaw velocity, and the difference in tire angular velocities, activate the steering system if it is determined that the vehicle is on a straight line path, and disable the feature of the steering system if it is determined that the vehicle is not on a straight line path.

Abstract: Methods and apparatus are provided for reducing steering wheel vibrations in electronic power steering systems. The apparatus includes a processor and performs a method that estimates an average angular wheel speed of at least one wheel of the vehicle; determines an average wheel angle from the average angular wheel speed; generates sine and cosine functions of the average angular wheel angle; processes the sine and cosine functions with a steering wheel torque signal received from a torque sensor to extract amplitude components of at least one of the sine and cosine functions; reconstructs the sine and cosine functions using the steering wheel torque signal; combines the sine and cosine functions to provide a control signal, and controls the EPS system via the control signal to attenuate smooth road shake vibrations in a steering wheel of the vehicle.