Visteon Global Technolgoies, Inc.

Ford Global Technolgoies, LLC

Gregory James Stout

Yixin Yao

Brian James Andonian

Bing Zheng

Muqtada Husain

Maged Radamis

Richard Michael Krzesicki

Kevin Jerome Pavlov

Michael K Liubakka

Brian Christian Orr

Zhesheng Li

Zilai Zhao

Benrouz Ashrafi

An automotive vehicle steering system has an actuator () for steering a wheel (). A shaft () passes axially through the interior of a housing () of the actuator and through a rotor tube () journaled for rotation within the housing. On the exterior of the housing one end of the shaft is coupled to the wheel. An electric motor () within the interior of the housing rotates the rotor tube when the wheel is steered by a steering wheel. An internal screw thread () on the rotor tube and an external screw thread () on the shaft are operatively coupled by a set () of transmission rollers () to provide for bi-directional transmission of motion between the rotor tube and the shaft such that rotation of the rotor tube causes the shaft to move axially of the housing to steer the vehicle wheel and axial motion of the shaft due to wheel recovery from a turn rotates the rotor tube.

Automotive vehicle steering system having an electric motor powered linear actuator shaft for turning a steered wheel

The present invention involves a method and system of initial aligning wheels of vehicle steer-by-wire systems with two independent front road wheels in the real time. The method comprises providing a steering wheel control sub-system and a road wheel control sub-system, providing an initial alignment unit and procedure to align the road wheels and steering wheel, and receiving relative and absolute steering wheel angles and road wheel angles. The method further includes generating wheel aligning reference angles based on the relative and absolute wheel angle, generating the switch control signal based wheel aligning reference angles using the logic operation with the threshold, and determining the steer-by-wire systems in the control state or in the initial alignment state.

System and method of initial aligning wheels of vehicle steer-by-wire systems

A drive assembly including an electric motor and frequency variable generator for use with a multi-axle vehicle. The vehicle generally includes an engine driving a first axle and a drive assembly with an electric motor driving a second drive axle. The drive assembly includes a frequency variable generator with an input shaft driven by the engine and the electric motor electrically communicates with the generator to receive output power from the generator. Other details of selected embodiments of the invention include the frequency variable generator having a rotor coupled to rotate with the engine output shaft and a stator electrically connected to the electric motor. An inverter is electrically connected to an electrical power source, such as a battery or the frequency variable generator, as well as to the rotor. A controller communicates with the inverter and is configured to control the magnitude and frequency of the power communicated from the inverter to the rotor winding.

Multi-axle vehicle drive system

The present invention involves a method of controlling a vehicle steer-by-wire system having two independent road wheels. In one embodiment, the method comprises providing a steering wheel control sub-system to generate road wheel reference angles and to produce steering feel for a vehicle driver. The method further includes providing a road wheel control subsystem with servo control structure having road wheel angles and angular rates feedbacks including a road wheel controlled plant and a road wheel controller for controlling actual road wheel angles to track to road wheel reference angles. Moreover, a robust control is implemented in the road wheel controller to overcome affects of uncertainties and disturbances from the steer-by-wire system, vehicle, and external environment.

System and method of controlling a vehicle steer-by-wire system applying robust control

The present invention involves a system and method of controlling a variable steering ratio of a vehicle steer-by-wire system. The variable steering ratio control varies the steering ratio continuously according to steering angle and vehicle speed. The method comprises sensing an actual steering wheel angle and an actual speed of the vehicle and converting the actual steering wheel angle and vehicle speed into values in fuzzy sets based on a steering wheel angle and vehicle speed membership functions with linguistic term labels. The method further includes determining a corresponding degree of membership of the steering wheel angle and vehicle speed. The method further includes inferring a fuzzy road wheel reference angle output value by determining the degree of membership function for the road wheel reference angle using fuzzy rules based on the degrees of steering angle and the vehicle speed. The method further includes converting a fuzzy road wheel angle into an actual road wheel angle. The variable steering ratio can be adjusted according to the vehicle operator's desire with a progressive ratio setup.

Variable steering ratio control system and method

The present invention involves a system and method of controlling a vehicle steer-by-wire system to provide the variable and adjustable steering feel for the driver utilizing expert-type fuzzy logic technology. The steering wheel fuzzy logic controller controls the steering wheel torque to produce the variable and adjustable steering feel continuously based on changes in steering wheel angle, road wheel torque and vehicle speed.

Expert-type vehicle steering control system and method

One aspect of the present invention regards an automotive steering wheel control system having a steering wheel, a magnetorheological damper in communication with the steering wheel and a road wheel control system operably connected to the magnetorheological damper where the magnetorheological damper controls the steering wheel in response to a torque signal from the road wheel control system.

Steering control with variable damper assistance and method implementing the same

The present invention involves a method of controlling a vehicle steer-by-wire system having two independent road wheels. In one embodiment, the method comprises providing a steering wheel control sub-system to generate road wheel reference angles and to produce steering feel for a vehicle driver. The method further includes providing a road wheel control sub-system with a servo control system structure including a multivariable road wheel controlled plant and a multivariable road wheel controller for controlling actual road wheel angles to track to road wheel reference angles. The method further includes generating left and right road wheel reference angles from the steering wheel angle with a road wheel reference angle generator using variable left and right steering ratios and calibration processes based on calibration variables, wherein the road wheel reference angle generator has first and second stages to produce left and right road wheel reference angle outputs. The present invention also involves a system for controlling a vehicle steer-by-wire system having a road wheel reference generator.

System and method of controlling a steer-by-wire system having a road wheel reference angle generator

The present invention involves a system and method of controlling a steer-by-wire system to produce adjustable steering feel for A vehicle driver by providing control of reaction torque on a steering wheel of a vehicle. The method includes a quantitative description for the steering feel which is obtained by establishing a relationship of steering wheel reaction torque and steering wheel angle, road wheel torque, and vehicle speed. The system and method include steer-by wire system closed-loop feedback controls with inner torque loop, steering wheel rate feedback loop, and steering wheel angular position feedback loop to implement providing the steering feel, active steering wheel return with the different rotation rate, steering wheel stop according to the road wheel angular position in a parking state, and directional angle reference generation to road wheels.

System and method of controlling vehicle steer-by-wire systems with adjustable steering feel

The present invention involves a method of controlling a vehicle steer-by-wire system having two independent road wheels. In one embodiment, the method comprises providing a steering wheel control sub-system to generate road wheel reference angles and to produce steering feel for a vehicle driver. The method further includes providing a road wheel control sub-system including a road wheel controlled plant and a road wheel controller for controlling actual road wheel angles to track to road wheel reference angles. Moreover, the method includes applying road wheel angles and angular rates as feedback signals to implement the left and right road wheel angles tracking for left and right road wheel reference angles in the road wheel control system with servo control system structure. The method further includes implementing a gain scheduling control in the road wheel controller to compensate the gain change of the controlled road wheel plant for overcoming non-linearity of the road wheel system, The present invention also involves a system of controlling a vehicle steer-by-wire system applying gain scheduling.

System and method of controlling a vehicle steer-by-wire system applying gain scheduling control

A differential gear assembly including a differential housing and a ring gear mounted externally to the differential housing by a clamp. The differential housing and the ring gear each include an annular flange extending therefrom and the clamp includes a pocket which is adapted to receive the annular flanges therein. In another aspect, the flanges include opposing angled surfaces and the pocket includes opposing angled sides, whereby when the clamp is placed to the flanges, the angled surfaces of the flanges engage the angled sides of the clamp such that the clamp provides an axial clamping force to the flanges.

Differential assembly

The present invention involves a method of controlling a vehicle steer-by-wire system having two independent road wheels. In one embodiment, the method comprises providing a steering wheel control sub-system to generate road wheel reference angles and to produce steering feel for a vehicle driver. The method further includes providing a road wheel control sub-system including a multivariable road wheel controlled plant and a multivariable road wheel controller for controlling actual road wheel angles to track to road wheel reference angles within a servo control system structure having road wheel angular position feedback and road wheel angular rate feedback loops. The method includes modeling the multivariable road wheel controlled plant and implementing the multivariable road wheel controller. Moreover, the method includes applying road wheel angles and angular rates as feedback signals to construct a servo control system with the multivariable controlled plant and the multivariable road wheel controller to implement the left and right road wheel angles tracking for left and right road wheel reference angles. Then, the method includes receiving left and right road wheel reference angles being based on the steering wheel angle command from the steering wheel control sub-system and receiving the left and right road wheel angles from the multivariable road wheel controlled plant. The method includes calculating the left and right road wheel angle errors based on the left and right road wheel angles and left and right road wheel reference angles and generating the left and right road wheel torque control variables from the multivariable road wheel controller with servo control performances based on the left and right road wheel angle errors. After generating road wheel torque control variables, the method includes applying torque control variables of the multivariable road wheel controller to the multivariable controlled plant to control tracking of the actual left and right wheel angles with the left and right road wheel reference angles, respectively.

System and method of controlling vehicle steer-by-wire systems

The present invention involves a method of controlling a vehicle steer-by-wire system having two independent road wheels. In one embodiment, the method comprises providing a steering wheel control sub-system to generate road wheel reference angles and to produce steering feel for a vehicle driver. The method further includes providing a road wheel control sub-system including a multivariable road wheel controlled plant and a multivariable-road wheel controller for controlling actual road wheel angles to track to road wheel reference angles within a servo control system structure having road wheel angular position feedback and road wheel angular rate feedback loops. Moreover, the method includes implementing the multivariable road wheel controller to control tracking of the actual left and right wheel angles with the left and right road wheel reference angles, respectively. The method further includes decoupling the left and right road wheel angles with the multivariable road wheel controller in the road wheel servo control system. The multivariable road wheel controller controls the left and road wheel angle based only on the left road wheel reference angle independent of the right road wheel reference angle. Also, the multivariable road wheel controller controls the right road wheel angle based only on the right road wheel reference angle independent of the left road wheel reference angle.

System and method of controlling a vehicle steer-by-wire system applying multivariable decoupling control

A steer-by-wire system of the preferred embodiment of the invention includes a steering sensor, a turning subsystem, a vehicle sensor, and a controller subsystem. The turning subsystem further includes a first turning actuator to adjust a turning angle of a first road wheel, a first turning sensor to sense first turning factors of the first turning actuator, a second turning actuator to adjust a turning angle of a second road wheel, and a second turning sensor to sense second turning factors of the second turning actuator. The controller subsystem is connected to the steering sensor, to the first turning sensor, to the second turning sensor, and to the vehicle sensor. The control subsystem independently controls the first turning actuator and the second turning actuator.

Steer-by-wire system with first and second steering actuators

The present invention includes a system and a method for generating steering reaction torque in a steer-by-wire steering system. The system includes a manually steerable member; a feedback generator; a vehicle speed sensor; a steering position sensor; and a steering actuator load sensor. A control unit calculates a set of blended reaction torque values by receiving input signals from the steering position sensor and the steering actuator load sensor. The control unit operates on the input signals and computing a set of reaction torque values, and blending the reaction torque values into set of blended reaction torque values. The set of reaction torque equations comprises a plurality of non-linear functions that is adapted for real-time, continuous operation upon the input signals from the sensors. The set of blended reaction torque values is speed-sensitized based on vehicle speed and transmitted to the feedback generator to generate steering feel in the manually steerable member.

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Ann Arbor, MI, United States of America

Gregory James Stout