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: Methods, system and apparatus are provided for suppression of steering wheel vibrations generated by an electric power steering system of a vehicle. A feedback controller is provided that extracts information from ABS pulse trains communicated over the vehicle's LAN to generate estimates of instantaneous tire position and angular velocity. The estimated tire position is used to generate carrier signals. The carrier signals are then processed with a measured dynamic disturbance signal to extract periodic content of the torque sensor. The estimated tire frequency is applied to a stored inverse motor drive-to-sensor torque transfer function to generate gain and phase adjustments that, along with the extracted periodic content of the torque sensor, can be applied to carrier signals to generate a gain-and-phase-compensated motor drive signal.

Abstract: A method to balance a wheel assembly. In a first aspect, corrective balance weights and position thereof are determined by a balancer and a closest corrective balance weight thereto is chosen, as well as one of higher and one of lower weight increment for each plane; chosen weights are paired to provide minimized residual and then attached to the planes of the wheel assembly. In a second aspect, imbalance weights are determined by a balancer; a pair of corrective balance weights, one at least ½ the determined imbalance weight are chosen, each separated by determined position angles to minimize residual and then respectively attached to the corrective balance plane(s) of the wheel assembly.

Abstract: Embodiments of a dual path hydraulic strut mount are provided, as are embodiments of a vehicular suspension system including a dual path hydraulic strut mount. In one embodiment, the dual path hydraulic strut mount includes an outer elastomeric module and an inner hydraulic module, which is mounted in the outer elastomeric module. The inner hydraulic module is configured to operate in an active damping mode for axial displacements of the dual path hydraulic strut mount less than a threshold value and in a substantially inactive damping mode for axial displacements of the dual path hydraulic strut mount greater than the threshold value.

Abstract: A method for testing a tire of a vehicle that includes the steps of creating a first condition comprising a first slip angle of the tire, obtaining a first set of data regarding performance of the tire under the first condition, creating a second condition comprising either a second slip angle or lateral displacement of the tire, obtaining a second set of data regarding performance of the tire under the second condition, and determining the transient response of the lateral force and aligning moment of the tire, using the first set of data and the second set of data.

Abstract: Dampers for vehicle suspensions include a housing comprising a tube attached to a wheel axle of a vehicle and a piston rod extending from a piston within the tube and attached to the vehicle body. The piston divides the tube into first and second chambers. In order to damp responses when minor smooth road imperfections impart low force excitations to the wheel of the vehicle, a fluid bypass passageway in the form of a sleeve is positioned around the tube and overlies the piston. This provides second stage quasi-ideal damping at low force excitations to the wheels and thus to the wheel axles of the vehicle. The sleeve communicates with the first and second chambers through metered orifices or valves. As low force excitations from smooth road imperfections displace fluid within the tube through the metered orifices or valves, the orifices damp responses to the low force excitations, thereby smoothing the ride of the vehicle.

Abstract: A raw runout signal of a tire is bandpass filtered utilizing appropriate, empirically determined, low and high tire order corners to determine the bandpass of the bandpass filter. A band-limited runout signal is then obtained and is examined for characteristic signal patterns of local runout which are known to exhibit periodically modulated cabin interior sound during vehicle movement, usually driving conditions involving highway speeds and smooth roads, which is audibly detectable by passengers based upon, for example, empirical analysis wherein the maximum gain of the bandpass filter is, preferably, unity.

Abstract: A method to reduce vehicular sensitivity to torsional smooth road shake (SRS) at the steering wheel provided by selectively increasing reverse driven-impedance of the steering system via an effective dynamic tuned vibration absorber comprising the existing power steering motor inertia supported on the torsional stiffness of the gearing to the rack in the case of a REPS system, or of the column rotary shaft in the case of a CEPS system.

Abstract: A steering wheel and column assembly is provided for deployment on a vehicle. In one embodiment, the steering wheel and column assemblies comprises: (i) a steering column housing, (ii) a rotatable steering assembly, and (iii) a torsional damper device. The rotatable steering assembly includes a steering column shaft, which is rotatably coupled to the steering column housing, and a steering wheel, which is fixedly coupled to the steering column shaft. The torsional damper device includes a stator body, which is fixedly coupled to the steering column housing, and a rotor body, which is fixedly coupled to the rotatable steering assembly. The rotor body frictionally engages the stator body to produce a predetermined coulomb torque frictional resistance.

Abstract: A raw runout signal of a tire is bandpass filtered utilizing appropriate, empirically determined, low and high tire order corners to determine the bandpass of the bandpass filter. A band-limited runout signal is then obtained and is examined for characteristic signal patterns of local runout which are known to exhibit periodically modulated cabin interior sound during vehicle movement, usually driving conditions involving highway speeds and smooth roads, which is audibly detectable by passengers based upon, for example, empirical analysis wherein the maximum gain of the bandpass filter is, preferably, unity.

Abstract: A method for testing a tire of a vehicle that includes the steps of creating a first condition comprising a first slip angle of the tire, obtaining a first set of data regarding performance of the tire under the first condition, creating a second condition comprising either a second slip angle or lateral displacement of the tire, obtaining a second set of data regarding performance of the tire under the second condition, and determining the transient response of the lateral force and aligning moment of the tire, using the first set of data and the second set of data.

Abstract: A method for measuring low amplitude dynamic properties of a steering column includes mounting the steering column into a test fixture and performing test runs. The test runs include subjecting the input end of the steering column to input excitations and measuring output conditions, which include at least one of acceleration, velocity and position, and determining whether the output conditions are within a predetermined output range. Input excitations may include sinusoidal excitations having a selected frequency range, torque, or displacement; or dither excitations. The selected torque or displacement is determined using open loop calculations from the output conditions, to achieve target acceleration levels. Data is interpreted to determine the natural frequency or rim gain of the steering column, which are compared to predetermined permissible ranges. The maximum steering wheel rim gain permissible level may be equal to approximately 1 divided by the polar moment of inertia of the wheel.

Abstract: A method of controlling a motor current for a vehicle having a motor and a steering system includes the steps of obtaining a torque signal from the steering system, calculating a torque, and adjusting the motor current based at least in part on the torque signal, the torque gain, or both.

Abstract: A vehicle engine mount system comprises a housing and an inertia track assembly that forms a first fluid chamber with an upper compliant member and a second fluid chamber with the second end of the housing. The inertia track assembly has first and second passageways therethrough for conducting fluid between the first and second fluid chambers. The first passageway has a substantially greater flow resistance than the second. First and second switches are coupled to the first and second passageways, respectively, for selectively enabling the first and second switches to control fluid displacement between the first fluid chamber and the second fluid chamber.

Abstract: A method for analyzing the output of a rotary sensor, such as that coupled to a vehicle wheel assembly. In one embodiment, the method detects periodic irregularities in the output of an incremental rotary sensor and uses those irregularities with a reference signal and a pattern comparison technique to determine the absolute angular position of the sensor.

Abstract: A cord reinforced resilient membrane (or diaphragm) having a high radial (transverse) stiffness and a relatively low axial stiffness, wherein the cord reinforced resilient membrane has adapatability for use in both hydraulic and conventional strut mounts, as well as other applications, and wherein the radial stiffness provided by the cords is directionally tunable for utilization in a particular application.

Abstract: A method for measuring low amplitude dynamic properties of a steering column includes mounting the steering column into a test fixture and performing test runs. The test runs include subjecting the input end of the steering column to input excitations and measuring output conditions, which include at least one of acceleration, velocity and position, and determining whether the output conditions are within a predetermined output range. Input excitations may include sinusoidal excitations having a selected frequency range, torque, or displacement; or dither excitations. The selected torque or displacement is determined using open loop calculations from the output conditions, to achieve target acceleration levels. Data is interpreted to determine the natural frequency or rim gain of the steering column, which are compared to predetermined permissible ranges. The maximum steering wheel rim gain permissible level may be equal to approximately 1 divided by the polar moment of inertia of the wheel.

Abstract: A steering wheel and column assembly is provided for deployment on a vehicle. In one embodiment, the steering wheel and column assemblies comprises: (i) a steering column housing, (ii) a rotatable steering assembly, and (iii) a torsional damper device. The rotatable steering assembly includes a steering column shaft, which is rotatably coupled to the steering column housing, and a steering wheel, which is fixedly coupled to the steering column shaft. The torsional damper device includes a stator body, which is fixedly coupled to the steering column housing, and a rotor body, which is fixedly coupled to the rotatable steering assembly. The rotor body frictionally engages the stator body to produce a predetermined coulomb torque frictional resistance.

Abstract: The system and method described herein can be used to reduce the effects of periodic vibrations in an electric power steering (EPS) system for a vehicle, particularly, those that can lead to smooth road shake (SRS), torsional nibble, and/or other undesirable conditions. According to an exemplary embodiment, an electric motor is used to purposely generate counter-acting vibrations in the EPS system to cancel out the periodic vibrations generated by the wheel assemblies or corners.

Abstract: A decoupled mono tube damper assembly includes an outer tube attached to a vehicle's unsprung mass. The outer tube has a base and a sleeve end. An outer tube sleeve engaging end of an inner tube is slidingly engaged with the sleeve end. The inner tube has an end distal to the sleeve engaging end, and is attached to the vehicle's sprung mass at the distal end. A damper rod has one opposed end extending axially into a base aperture, and an opposed end connecting to the inner tube. The rod moves axially relative to the outer tube. A low amplitude energy-managing member is operatively disposed within the outer tube, and has a throughbore receiving the rod. A travel-limiting member attaches to the rod and is engageable with the energy-managing member to constrain axial movement of the rod through the outer tube base to a predetermined limit.