Abstract: Example steering wheel systems and torque feedback actuator assemblies for use in steer-by-wire vehicles are described herein. An example steering wheel system includes a steering wheel and a torque feedback actuator assembly. The torque feedback actuator assembly includes a housing and a helical gear rotatably disposed in the housing. The steering wheel is coupled to and coaxially aligned with the helical gear. The torque feedback actuator assembly also includes a motor with a worm gear engaged with the helical gear to provide torque feedback to the steering wheel by driving the helical gear.

Abstract: Upon determining calibration parameters for a single-loop controller that minimize a difference between an input to the single-loop controller and a response from the single-loop controller, calibration parameters for a cascade controller are determined based on the determined calibration parameters for the single-loop controller. The cascade controller includes a secondary controller and a primary controller. The calibration parameters for the cascade controller are provided to a second computer in a vehicle.

Abstract: A computer includes a processor and a memory, the memory storing instructions executable by the processor to detect an actual steering column torque and an actual steering wheel angle, predict a steering wheel torque with a state-estimation algorithm that outputs a plurality of vehicle states including the predicted steering wheel torque, adjust the plurality of vehicle states based on an algorithm noise that is based on a steering wheel angular speed to generate estimated vehicle states, output the estimated vehicle states including an estimated user-applied steering wheel torque, and transition from an autonomous mode to a manual mode when the estimated steering wheel torque exceeds a threshold. The state-estimation algorithm accepts input including the actual steering column torque and the actual steering wheel angle and outputs the plurality of vehicle states.

Abstract: A system for correcting a steering offset generated by an active steering system of a vehicle includes a vehicle comprising a pair of steered road wheels. The system also includes a controller configured to direct a change to an angle of the steered road wheels when a determined steering state of the vehicle is a steering slowly state.

Abstract: A computer is programmed to determine a trajectory of a first vehicle. The computer is programmed to determine whether a second vehicle blocks the trajectory. Upon such determination, the computer sends an instruction to the second vehicle to adjust the second vehicle speed. The computer is programmed to determine the instruction based on the determined trajectory of the first vehicle, a second vehicle location, and a second vehicle speed.

Abstract: Example steering wheel systems and torque feedback actuator assemblies for use in steer-by-wire vehicles are described herein. An example steering wheel system includes a steering wheel and a torque feedback actuator assembly. The torque feedback actuator assembly includes a housing and a helical gear rotatably disposed in the housing. The steering wheel is coupled to and coaxially aligned with the helical gear. The torque feedback actuator assembly also includes a motor with a worm gear engaged with the helical gear to provide torque feedback to the steering wheel by driving the helical gear.

Abstract: A computer includes a processor and a memory, the memory storing instructions executable by the processor to input a current trajectory and a planned path for a vehicle to a state observer algorithm to obtain a target yaw rate, compare the target yaw rate to an actual yaw rate to determine one of an oversteer or an understeer condition, and apply brakes on one or more but less than all wheels of the vehicle based on determining the understeer or oversteer condition.

Abstract: A computer includes a processor and a memory, the memory storing instructions executable by the processor to detect an actual steering column torque and an actual steering wheel angle, predict a steering wheel torque with a state-estimation algorithm that outputs a plurality of vehicle states including the predicted steering wheel torque, adjust the plurality of vehicle states based on an algorithm noise that is based on a steering wheel angular speed to generate estimated vehicle states, output the estimated vehicle states including an estimated user-applied steering wheel torque, and transition from an autonomous mode to a manual mode when the estimated steering wheel torque exceeds a threshold. The state-estimation algorithm accepts input including the actual steering column torque and the actual steering wheel angle and outputs the plurality of vehicle states.

Abstract: Example steering wheel systems and torque feedback actuator assemblies for use in steer-by-wire vehicles are described herein. An example steering wheel system includes a steering wheel and a torque feedback actuator assembly. The torque feedback actuator assembly includes a housing and a helical gear rotatably disposed in the housing. The steering wheel is coupled to and coaxially aligned with the helical gear. The torque feedback actuator assembly also includes a motor with a worm gear engaged with the helical gear to provide torque feedback to the steering wheel by driving the helical gear.

Abstract: A computer includes a processor and a memory storing processor-executable instructions. The processor is programmed to record steering-system torque in response to a difference between a detected steering angle and a requested steering angle exceeding an angle threshold, increment a counter based on the recorded steering-system torque, and set a repair indicator in response to the counter exceeding a counter threshold.

Abstract: A computer includes a processor and a memory storing instructions executable by the processor to determine at least one of a vehicle pitch or a longitudinal center of gravity from data measured while deactivating a first brake for a first axle and applying a second brake for a second axle, and operate the vehicle based on the at least one of vehicle pitch or longitudinal center of gravity. The instructions may further include to determine a vehicle weight from the data, and operate the vehicle based on the vehicle weight.

Abstract: A computer includes a processor and a memory storing instructions executable by the processor to determine at least one of a vehicle pitch or a longitudinal center of gravity from data measured while deactivating a first brake for a first axle and applying a second brake for a second axle, and operate the vehicle based on the at least one of vehicle pitch or longitudinal center of gravity. The instructions may further include to determine a vehicle weight from the data, and operate the vehicle based on the vehicle weight.

Abstract: Methods and systems for analyzing and/or calibrating an adaptive steering system are disclosed. One method may include rotating a hub that is configured to engage a steering shaft over a predetermined range of hub angles using a gear and an internal electric motor in response to a control signal. A torque required to rotate the hub as a function of the hub angles may be determined, as well as whether the torque is within a predefined torque window. The method may be used to analyze the overall friction in the adaptive steering wheel assembly. In one embodiment, the method may be performed with the steering wheel assembly fully assembled and the internal electric motor covered and inaccessible. The torque may be determined by calculating the torque based on a current draw of the internal electric motor.

Abstract: A computer includes a processor and a memory storing processor-executable instructions. The processor is programmed to record steering-system torque in response to a difference between a detected steering angle and a requested steering angle exceeding an angle threshold, increment a counter based on the recorded steering-system torque, and set a repair indicator in response to the counter exceeding a counter threshold.

Abstract: A computer includes a processor and a memory storing processor-executable instructions. The processor is programmed to determine a deviation between a predicted value and one of a sensed steering angle and a sensed steering torque of a vehicle, output a service request in response to the deviation exceeding a first threshold, and perform a minimal risk condition in response to the deviation exceeding a second threshold.

Abstract: A vehicle includes an adaptive front steering system including an assist motor that provides an overlay angle superimposed on a steering wheel angle. External torque to the assist motor is estimated by a controller and evaluated to determine whether it is the result of an external disturbance. If so, the controller evaluates whether the external disturbance is a road disturbance, such as by determining that road wheel speed varied from the vehicle speed or that an impact site is present in outputs of external sensors of the vehicle. If a road disturbance is determined to have occurred, compliance may be introduced in order to reduce the transmission of torque to the steering wheel. Compliance may be introduced by adjusting current to the assist motor, a target angle to the assist motor, reducing gain in the control system for the assist motor, or shorting leads of the assist motor.

Abstract: A system for a vehicle includes a gear and a plate fixed to the gear. The gear is driving by a motor for providing relative rotation between a steering wheel and steering shaft of the vehicle in an adaptive front steering system. The system includes a solenoid including a coil and a pin moveable relative to the coil to engage the plate based on a signal. A sensor is configured to detect a change in current through the coil associated with initial movement of the pin relative to the coil. The system includes a controller programmed to change the duty cycle signal in response to the change in current to slow movement of the pin to reduce or eliminate a clicking noise associated with the pin seating in an extended position or retracted position.

Abstract: A method for detecting steering misalignments in an adaptive steering system of a motor vehicle, wherein the adaptive steering system has a steering wheel angle sensor for detecting a value representative of a steering wheel angle, an adaptive angle unit for detecting a value representative of an adaptive angle, and a wheel angle detection unit for detecting a value representative of a wheel angle. The method including detecting a value representative of the steering wheel angle, detecting a value representative of the adaptive angle, detecting or determining a value representative of the wheel angle, and computing a comparison value.

Abstract: Example steering wheel systems and torque feedback actuator assemblies for use in steer-by-wire vehicles are described herein. An example steering wheel system includes a steering wheel and a torque feedback actuator assembly. The torque feedback actuator assembly includes a housing and a helical gear rotatably disposed in the housing. The steering wheel is coupled to and coaxially aligned with the helical gear. The torque feedback actuator assembly also includes a motor with a worm gear engaged with the helical gear to provide torque feedback to the steering wheel by driving the helical gear.

Abstract: Methods, apparatus, and articles of manufacture to correct clear vision errors in a vehicle steering system are disclosed. An example apparatus includes a first sensor and a second sensor to measure a current position of a steering column and a current position of a steering wheel in a vehicle steering system. The example apparatus further includes a non-uniformity manager to map the current position to an offset, and an active steering system to apply the offset to adjust the current position of the steering wheel to a nominal position of the steering wheel to compensate for a clear vision error.