Abstract: A motor system includes first and second solid-state relays disposed between an inverter configured to control energization to a first coil set of a motor and an in-vehicle battery for supplying power to the inverter, and connected in series in this order in a direction from the inverter to the battery. The first solid-state relay has a first diode of which a forward direction is from the battery to the inverter. The second solid-state relay has a second diode of which a forward direction is from the inverter to the battery. Motor relays, each having a third diode of which a forward direction is from the neutral point to the inverter, are connected to the phase coils of the first coil set. When power supply from the battery to the inverter is interrupted, the first solid-state relay is turned off after the motor relays are turned off.

Abstract: A steering control device for use in a steer-by-wire system is provided. The steering control device controls a reaction force device and a turning device of a steer-by-wire system. The steering control device includes a steering wheel torque controller that calculates a basic reaction force torque command value being a basic value of a reaction force torque command value so that a detection value of the torque sensor follows a target value. The steering control device further includes an end controller that stops a control of the steering wheel torque controller when: an absolute value of angle of the reaction force device or the turning device is equal to or greater than a limit angle value; and a physical quantity corresponding to an output torque of the turning device and the detection value of the torque sensor are values corresponding to approach to the limit angle value.

Abstract: A steering angle sensor assembly for a vehicle steering gearbox can include a protective housing mounted to a housing of the steering gearbox and a steering angle sensor. The protective housing can include a case, a cover and a gasket connected to each other such that the case, the cover and the gasket form an interior space with the gasket sandwiched between the case and the cover. Each of the case and the cover can include an opening configured to receive a pinion shaft of the steering gearbox when the steering angle sensor assembly is mounted on the housing. The steering angle sensor can be secured in the interior space of the protective housing and can engage the pinion shaft when the protective housing is mounted to the housing and the pinion shaft is received by the opening in each of the case and cover.

Abstract: Provided is a torque sensor and an electric power steering system, which are capable of suppressing a detection property fluctuation between two magnetic sensors. A retaining portion is disposed at first and second magnetism collecting members in such a position as to be magnetically symmetrical with respect to first and second magnetic sensors.

Abstract: A technique for reducing an operation noise even when a high-pass filter is used for controlling a motor is provided. A controller is used in a motor control system for driving a motor used for position control by using a drive circuit and an inverter. The controller includes a current control block for receiving a motor current and outputting a reference voltage, a motor control circuit for outputting a signal indicating a duty ratio from the reference voltage output from the current control block, a dead band compensation block for calculating a compensation value of a non-linear element of a drive system, and an adder. The dead band compensation block outputs a duty value corresponding to the dead band at a timing at which the motor current crosses zero. The adder adds the duty value to a signal indicating the duty ratio and outputs the signal.

Abstract: The vehicle control system is applied as a system of a vehicle mounted with an EPS device having an electric motor driven to control the steering angle. The vehicle control system includes a controller configured to perform steering control for controlling an energization of the electric motor to control the steering angle of the wheels. When the wheels are held after being steered by a specific steering in the steering control, the controller performs a steering return process in which the wheels are turned back and held in a direction opposite to a steering direction of the specific steering. And during a stationary steering-holding in which the steering angle is held and the vehicle is stopped, the controller performs an energization suppression process for reducing energization to the electric motor to be smaller than the energization before the stationary steering-holding.

Abstract: A motor control method for controlling a motor of an electric power assisted steering system includes: generating a low pass torque signal and a high pass torque signal, respectively; generating a low frequency assist torque signal using the low pass torque signal and the vehicle speed; generating a high frequency assist torque signal using a high pass torque signal and the vehicle speed; generating a torque command signal using a sum of the low frequency assist torque signal and the high frequency assist torque signal; and generating a voltage output signal for driving the motor using the torque command signal.

Abstract: A steering controller is disclosed, wherein the steering controller is configured in such a way as to obtain input signals from at least one sensor for detecting a steering request of a motor vehicle driver and at least one driver assistance system, wherein the steering controller is also configured to generate an actuating signal for a power electronics unit. The actuating signal is assembled from two components, wherein the steering controller is configured so that the first component is ascertained from the input signal from the at least one sensor. The signals from the driver assistance system have no influence on the first component. The second component is ascertained from the input signals from the at least one driver assistance system, wherein the signals from the sensor are taken into account in the second component.

Abstract: A motor control system includes an inverter, and a control unit that feedback-controls the inverter. The control unit includes a voltage control unit that calculates a voltage command value indicating a voltage to be applied to the motor from the inverter based on a current deviation between a current command value and an actual current detection value, and a torque ripple compensation unit that adds a compensation value for compensating a torque ripple in the motor to a signal value on at least one of an upstream side and a downstream side in a signal flow passing through the voltage control unit. The torque ripple compensation unit calculates the compensation value based on an actual angular velocity at which the motor rotates and the target current command value, and based on advance angle control for compensating a response delay of the motor control system with respect to the compensation value.

Abstract: Inverter circuits are provided for motor winding sets, respectively. Control units are provided for the motor winding sets to generate control signals related to driving of the inverter circuits and control currents flowing through the motor winding sets, respectively, thereby controlling driving of a motor. The control mode includes a manual steering mode for controlling the motor according to a steering operation on a steering wheel by a driver and an automatic steering mode for controlling the motor independently of the steering operation on the steering wheel by the driver. The control units are capable of switching the control modes and differentiate the current control according to the control mode. By making the current control different according to the control mode, it is possible to attain optimal characteristics which correspond to each control mode.

Abstract: A system and method for controlling the steering of a vehicle includes a processor, a velocity sensor in communication with the processor a steering angle sensor in communication with the processor, accelerometer in communication with the processor and a steering angle controller in communication with the processor. The processor is configured to receive the acceleration of the vehicle from the accelerometer and the velocity from the velocity sensor, determine the estimated tie-rod force utilizing the lookup table tie-rod force estimation lookup table, and instruct the steering wheel angle controller to apply an additional force substantially equal to the estimated tie-rod force to the steering torque.

Abstract: In a steering assistance device 1, a steering control unit 74 causes a first auxiliary unit 14 to generate torque with reducing by a predetermined amount and causes a second auxiliary unit 20 to generate torque equal to or less than the decreased predetermined amount, in a case where the first auxiliary unit 14 is able to generate a steering assistance force such that a steering angle of a vehicle can reach a target steering angle determined according to curvature so as to make the vehicle travel in the center of a lane.

Abstract: Provided is a control device for an AC rotating electric machine, which includes: a temperature detection unit configured to detect a temperature of a protection unit provided in an object to be protected when a current is supplied from a power conversion circuit including a switching element to the AC rotating electric machine and output, as a detected temperature, one of the temperature and a temperature of the object to be protected that is estimated from the temperature; a temperature compensation unit configured to calculate, through use of the detected temperature output from the temperature detection unit, a compensated temperature equal to or higher than the detected temperature; and a torque limiting unit configured to limit, through use of the compensated temperature calculated by the temperature compensation unit, a torque command value input thereto.

Abstract: Even in the case that the steered wheels are turned by an actual turning angle due to a disturbance from the road surface, and the steering shaft, which is mechanically connected to the steered wheels, attempts to rotate, a command current to an assist motor is set so that the actual turning angle becomes a corrected target turning angle. The force (torque) that attempts to cause rotation of the steering shaft due to the disturbance input from the road surface is instantaneously canceled by the assist motor.

Abstract: A control device includes: a first power converter applying a voltage to a first winding; a second power converter applying a voltage to a second winding; a first power supply circuit supplying power to the first power converter; a second power supply circuit supplying power to the second power converter; a current command calculator; a first current controller; and a second current controller. The second power supply circuit supplies power at a voltage higher than a voltage of the first power supply circuit. The current command calculator calculates a first voltage usage state, which is an indicator value correlated with a magnitude of the output voltage of the first power converter with respect to a power supply voltage output at a time of supply of power by the first power supply circuit, and calculates the second current command based on the first voltage usage state.

Abstract: A steering control device (ECU) comprises a base assist unit for generating a basic assist torque and a steering torque correction unit. The steering torque correction unit outputs a corrected steering torque, which is decreasingly corrected so that an absolute value becomes smaller than an absolute value of a steering torque when a viscous load is requested to be applied to a driver by decreasing the assist torque. The base assist unit includes a target steering torque calculation unit and a servo controller. The target steering torque calculation unit calculates the target steering torque based on a steering torque. The servo controller calculates the basic assist torque to cause the corrected steering torque to follow the target steering torque.

Abstract: A trailer backup assist system for motor vehicles includes an auxiliary user input feature that can be used by a vehicle operator to provide a steering curvature command corresponding to a desired vehicle path curvature without requiring a user to move a steering wheel of the motor vehicle. The trailer backup assist system is configured to control a vehicle speed while the vehicle is backing up with a trailer attached thereto utilizing an input comprising at least one of a steering curvature command and an angle of a trailer relative to the vehicle. The trailer backup assist system controls at least one of a brake system, an engine torque, and a transmission gear selection to thereby control vehicle speed in a reverse direction.

Abstract: A power assist device for supporting steering of a motor vehicle includes a steering column shaft and a housing. The shaft has a rotor and the housing has a stator. The stator is arranged in the radial direction with respect to the rotor. The rotor is a disk, and at least one magnet is arranged on the radially outer edge of said rotor.

Abstract: Technical solutions are described for attenuating dither noise in a steering system. An example method includes computing multiple filter parameters, each filter parameter based on a corresponding signal in the steering system. The method further includes determining at least one final filter parameter from the plurality of filter parameters by arbitrating the plurality of filter parameters. The method further includes dynamically configuring a filter using the at least one final filter parameter. Further, the method includes filtering a motor torque command using the filter, a filtered motor torque command being applied to a motor to generate a corresponding amount of torque.

Abstract: An electric steering device includes a motor and a control circuit. The motor applies a steering force to a steering mechanism of a vehicle. The control circuit includes an inverter that converts DC power of a DC power supply to AC power and supplies the AC power to the motor, and a power supply relay that permits or blocks a current flow to the motor through the inverter. In the control circuit, the power supply relay is provided on a ground line connecting the inverter and a ground.

Abstract: A servo controller calculates a base assist torque so that a steering torque follows a target steering torque. A convergence control calculation unit provided as a correction control calculation unit calculates a correction control value in accordance with a steering speed which is a steering state value. A torque converter outputs a torque limit value determined by converting a current limit value into a torque to a servo limit value calculation unit. The servo limit value calculation unit calculates the servo limit value so that an absolute value of the servo limit value to be larger than an absolute value of the torque limit value in at least a part of a region of the steering speed or the correction control value.

Abstract: Provided is an electric power steering control device capable of improving steering feeling. When the voltage of a battery is within the range of usual voltage, a gain target value is set to a usual value, and when the voltage of the battery is outside the range thereof, the gain target value is set to a value below the usual value. Then, it is determined whether or not a set gain at recovery of the voltage of the battery from outside the range of the usual voltage to within the range thereof is larger than a prescribed threshold. When determined to be larger than the prescribed threshold, the gain is set to immediately increase up to the gain target value, whereas when determined to be equal to or less than the prescribed threshold, the gain is set to gradually increase up to the gain target value.

Abstract: A method for a steering control of a vehicle to improve steering restoration when the vehicle escapes from a turn path via acceleration during high-speed turning. The vehicle steering control method includes determining whether or not a vehicle is rapidly accelerating in a high-speed turning state, and providing a restoration compensation torque in a vehicle steering restoration direction using a steering motor when it is determined that the vehicle is rapidly accelerating in the high-speed turning state. In particular, the restoration compensation torque is determined based on a relationship of a steering torque, a wheel speed, a number of revolutions of an engine, and a steering angular speed of the vehicle.

Abstract: A method for assembling a rack-and-pinion steering gear may involve introducing a steering pinion into a housing opening of a steering gear housing such that a region of a narrowed portion of a pinion shaft is situated at a level of a rack to be inserted, introducing the rack into the housing opening of the steering gear housing such that the rack is pushed past the narrowed portion of the pinion shaft into a setpoint position, and moving the pinion shaft farther into the steering gear housing to an end position such that a toothing region of the rack enters into engagement with a toothing of the steering pinion.

Abstract: An electric power steering apparatus including: a steering torque detector to detect a steering torque of a driver; a motor to assist a steering force of the driver; an estimated speed calculator to calculate an estimated speed, which is an estimated value of a rotation speed of the motor; an estimated speed corrector to correct the estimated speed based on the steering torque; an estimated angle calculator to calculate an estimated angle of the motor by integrating the estimated speed after the correction; and an electric power supply to supply electric power to the motor based on the estimated angle, wherein the estimated speed corrector corrects the estimated speed when a determination signal, which is based on a value obtained by removing a frequency component of steering of the driver from a derivative of the steering torque, the steering torque, and the estimated speed have the same signs.

Abstract: An ECU of a vehicle controls a motor on the vehicle. The ECU includes a microcomputer and a monitoring circuit. The monitoring circuit includes a rotation detection circuit that detects the number of rotations of the motor at a preset sampling interval, a control circuit including a logic circuit that controls an operation of the rotation detection circuit, and an inspection circuit that inspects of the control circuit. The microcomputer is started upon start of vehicle power supply and performs a specific process using the number of rotations of the motor detected by the rotation detection circuit. The inspection circuit performs the inspection of the control circuit in the monitoring circuit in a period in which the microcomputer is kept in a reset state after the vehicle power supply is turned on and which is within a sampling interval of the rotation detection circuit in the monitoring circuit.

Abstract: Disclosed is an automatic adjustment system for a steering wheel provided in a process line to support wheel alignment operation of a vehicle mounted with an OBD, includes a scanner for recognizing a vehicle identification number entered into the process line; an antenna that connects the OBD of the vehicle with the wireless diagnosis communication to transmit and receive data; a robot moves a vision sensor mounted on the front end portion thereof to the shooting position of the steering wheel in the vehicle through the attitude control, when the vehicle is seated in a centering position; and a control apparatus that analyzes the shooting image of the vision sensor to calculate the current distorted angle of the steering wheel and initialize by inputting the current distorted angle of the steering wheel to the steering angle sensor via the diagnosis communication connected with the OBD of the vehicle.

Abstract: A method for determining a driver's manual torque at a steering wheel of a vehicle which includes sensing a steering angle speed by a steering angle sensor, sensing a steering torque by a steering torque sensor at a steering column connected to the steering wheel, estimating a driver's manual torque applied by a driver at the steering wheel based on the sensed steering angle speed and the sensed steering torque by a Kalman filter by a controller, wherein during the estimation of the driver's manual torque a frictional torque is considered, and the frictional torque is estimated based on the steering torque which is sensed by the steering torque sensor, wherein the estimated frictional torque is taken into account as an interference factor during the estimation of the driver's manual torque in the Kalman filter. Also disclosed is an associated device.

Abstract: The present invention includes: first to fourth Hall elements for detecting steering torque; a first power supply circuit for supplying power to the first and second Hall elements; a second power supply circuit for supplying power to the second and third Hall elements; and a control device including a first abnormality determining unit for determining whether first and fourth torque signals are abnormal by preparing the first torque signal output from the first Hall element with the fourth torque signal output from the fourth Hall element and a second abnormality determining unit for determining whether second and third torque signals are abnormal by comparing the second torque signal output from the second Hall element with the third torque signal output from the third Hall element. With this, even when abnormality occurs in one of the first and second power supply circuits, the abnormality determination of an output signal can be continued.

Abstract: Methods for estimation of lost temperature increment after system restart for motor coil temperature estimation in an electric power steering apparatus of a motor vehicle with a power pack including an ECU with a temperature sensor and an electric motor. The methods allow to easily recover the lost heat increment value after restart of the system. Consequently, the estimation of the temperature of the motor coils will start from the correct temperature value. Damage of the motor due to overheat can be prevented. Further a more robust system diagnostics and a more accurate torque signal estimation can be provided.

Abstract: A motor driven power steering apparatus includes a steering logic unit for generating a current command to operate a drive motor according to a driving condition of a vehicle, a motor speed sensor for sensing a rotation condition of the drive motor to output a motor speed, a motor control unit for receiving the current command and the motor speed from the steering logic unit and the motor speed sensor, respectively, and calculating an output voltage from a voltage table according to current-speed based on the current command and the motor speed to output a voltage command to operate the drive motor, a coordinate conversion unit for converting the two-phase voltage command outputted from the motor control unit into a three-phase voltage, and a motor driving unit for outputting the three-phase voltage converted from the coordinate conversion unit to the drive motor as a PWM voltage.

Abstract: An electric power steering apparatus that drives a motor based a current command value and assist-controls a steering system by a driving-control of the motor. The apparatus includes a handle-returning control section that calculates a target steering angular velocity by using a steering angle, the vehicle speed, the steering torque and the current command value, calculates a handle-returning control current by using a limit-target steering angular velocity which is obtained by limiting the target steering angular velocity depending on steering angular velocity, and drives the motor by a compensated current command value which is obtained by adding the handle-returning control current to the current command value.

Abstract: A steering apparatus for a vehicle includes: a steering wheel comprising a shaft coupler connected to an upper steering shaft of a vehicle, and a first grip member and a second grip member disposed on the shaft coupler; a steering column having the upper steering shaft therein and connected with the shaft coupler to change the axial length thereof in accordance with driving modes; and a controller rotating at least one of the first grip member, the second grip member, and the shaft coupler, depending on the driving modes.

Abstract: Technical solutions described herein include a steering system that includes a motor that generates assist torque, and a controller that generates a motor torque command for controlling an amount of the assist torque generated by the motor. The steering system further includes a remote object assist module that computes a steering intervention based on a proximity of a vehicle from a detected object. The controller changes the motor torque command using the steering intervention.

Abstract: A method of managing over-temperature excursions in an electronic control unit of a control system having failed-fixed capability and an operationally independent temperature monitoring and power enable function. The method includes receiving a temperature signal indicative of a temperature associated with an electronic control unit, determining if the temperature associated with the electronic control unit exceeds a first selected threshold, determining if the temperature associated with the electronic control unit exceeds a second selected threshold, and ascertaining if an engine associated with the control system is operational. The method also includes that if the engine is not operational and the temperature exceeds the first selected threshold, then disabling an actuator associated with the control system.

Abstract: In described examples of methods and control systems to control a position and/or velocity of a machine, control circuitry is coupled to receive and dither a control signal, and to compute a control output value according to the dithered control signal and a control function. An inverter is coupled to the control circuitry, to control the position and/or velocity according to the control output value.

Abstract: An electric power steering apparatus includes a function to switch a control system of the motor between a torque control system of a torque system to control a motor output torque and a position and speed control system of a steering angle system to control a steering angle of a steering in accordance with an ON/OFF of a post-diagnosis automatic steering command being a judgment result of an automatic steering execution judging section; and a characteristic calculating section to calculate a fade gain signal F1 that applies a first fade characteristic of the torque system, a fade gain signal F2 that applies a second fade characteristic of the steering angle system, and a fade gain signal F3 that applies a third fade characteristic of the steering angle speed, sensitive to the steering torque.

Abstract: A hydraulic steering system for vehicles includes a steering control member; a hydraulic pump provided with a rotatable driving shaft on which the control member is fitted; a hydraulic actuating cylinder connected with two ports of the pump alternately operating as delivery side and return side of the pump and mechanically connected with a direction changing member, which determines a change in the direction by modifying orientation via an actuating cylinder as a function of the supply of hydraulic fluid to the cylinder from the pump by the steering control member. The driving shaft is dynamically connected with an electric motor/transmission assembly, which is activated alternatively by generating a rotational force auxiliary to the movement manually exerted on the steering control member or opposing the manually exerted movement, or by driving to rotate the driving shaft of the pump in place of the manual action driving the steering control member.

Abstract: A steering control unit includes a microcomputer that controls the driving of a motor on the basis of a steering torque to cause the motor to produce an assist force that is supplied to a steering mechanism as power to steer front wheels. The microcomputer calculates, on the basis of the steering torque, an assist component indicative of the assist force that the motor needs to produce. The microcomputer obtains vertical forces related to the front wheels that are calculated by hub units that rotatably support the front wheels and have front wheel sensors for detecting forces applied to the front wheels. The microcomputer compensates the assist component by using the obtained vertical forces, to reduce a change in load on a driver that is caused when vertical loads on the front wheels change.

Abstract: A method for operating an electric power steering system of a motor vehicle, wherein a steering wheel angle is specified by a steering handle as a measurement for a desired wheel steering angle for at least one steerable wheel of the motor vehicle, wherein an electric servo drive having an electric motor provides steering assistance, and wherein an additional restoring force is provided to compensate for increased internal friction in the power steering system based upon temperature, wherein the additional restoring force is reduced based upon a desired steering direction that is detected at the steering handle. Also disclosed is an associated electric power steering system, an associated computer program, and an associated control unit.

Abstract: A method for distinguishing intentional steering movements of a driver for influencing an intentional driving path of a motor vehicle from corrective steering movements of the driver as a reaction to unexpected deviations of the motor vehicle from the intentional driving path including ascertaining an instantaneous undisturbed motion of the vehicle along the driving path and calculating a reference value for a steering angle (SAR) corresponding to the ascertained, undisturbed motion of the motor vehicle or a reference value for a steering velocity (SVR) corresponding to the ascertained, undisturbed motion of the motor vehicle.

Abstract: A motor driving apparatus includes a first driving control circuit (an MCU, a driving circuit, an input circuit, a power management IC) and a second driving control circuit (an MCU, a driving circuit, an input circuit, a power management IC). The first driving control circuit and the second driving control circuit are configured to drive a corresponding winding group of winding groups of a motor, and have a master mode for outputting a synchronous trigger signal in synchronization with driving of the corresponding winding group and a slave mode for synchronizing the driving of the corresponding winding group with an input synchronous trigger signal. When an error has occurred in an operation of the first driving control circuit in the master mode, the second driving control circuit switches an operation mode of the second driving control circuit from the slave mode to the master mode.

Abstract: A steering control apparatus includes a microcomputer configured to control driving of a motor based on a steering torque so as to generate, for a steering mechanism, an assist force as power for turning front wheels. The microcomputer calculates an assist component indicating the assist force to be generated in the motor based on the steering torque, acquires steered moments about axes extending in a vertical direction of the front wheels from hub units that rotatably support the front wheels and include front wheel sensors configured to detect forces applied to the front wheels, respectively, and compensates for the assist component by using the acquired steered moments so as to generate, in the motor, a vibration suppressing force for suppressing a reverse input vibration.

Abstract: A method of controlling a motor of an electric power assisted steering system, the motor having a plurality of phases, the method comprising taking as an input an input signal indicative of a desired assistance torque and determining from the desired assistance torque a voltage to be applied to each of the phases of the motor, in which the step of determining the voltage to be applied to each of the phases comprises limiting the voltage determined to be applied to each of the phases of the motor dependent upon the voltage provided by a power supply to the motor.

Abstract: The power steering device is configured to: apply a required assist force only from a first electric motor until a predetermined period elapses, which is a period from a time point at which a driver starts steering to a time point at which a second-electric-motor drive start condition, which is a condition for starting drive of a second electric motor, is satisfied; when the predetermined period has elapsed, apply the required assist force from the first electric motor and a hydraulic actuator; and adjust an assist force by the first electric motor so that the assist force by the first electric motor is a value obtained by subtracting an assist force by the hydraulic actuator from the required assist force. As a result, the device can be downsized, and a sufficient required assist force can be generated from an initial stage of the steering.

Abstract: The present invention relates to a steering control apparatus and a steering control method for removing an inwardly caused disturbance or outwardly caused disturbance with respect to a vehicle. It is possible to efficiently remove a disturbance of a steering control apparatus which is generated due to various causes by: confirming a disturbance cause based on estimated frequencies estimated based on three factors that affect the steering control apparatus (i.e., a first estimated frequency estimated based on the estimation of a rack force, a second estimated frequency estimated based on a steering torque signal, and a third estimated frequency estimated based on a vehicle wheel rotational speed); then determining a compensation rate, which varies depending on whether the disturbance is an internally caused disturbance or an externally caused disturbance; and then applying the compensation rate to a steering current value.

Abstract: A steering control method for a vehicle, may include determining, by a controller, whether or not a vehicle is in a high-speed turning driving condition based on factors reflecting a driving state of the vehicle; determining, by the controller, whether or not a rapid acceleration is occurring in the vehicle when the controller determines that the vehicle is in the high-speed turning driving condition; and providing, by the controller, restoration compensation torque to a steering restoration direction of the vehicle by use of a steering motor when the controller determines that the rapid acceleration is occurring.

Abstract: An electric power tool may include a three-phase brushless motor configured to drive a tool, a gear reducer provided between the motor and the tool. The gear reducer is configured to selectively change a reduction ratio from the motor to the tool between a first reduction ratio and a second reduction ratio. The electric power tool may further include a motor controller configured to drive the motor with rectangular waves. The motor controller is configured to selectively change a conduction angle of each rectangular wave between at least a first conduction angle and a second conduction angle.

Abstract: A steering control device that can more appropriately transmit a road-surface reaction force to a steering wheel is provided. The steering control device feedback controls a steering angle to a target steering angle that is a target value of the steering angle. The steering control device includes an estimated axial force computation circuit that computes an estimated axial force so as to reflect a road-surface reaction force in a reaction force generated by a reaction force actuator. The estimated axial force computation circuit computes the estimated axial force by causing a friction compensation amount computation circuit and an efficiency compensation gain computation circuit to compensate an initial estimated axial force computed by an initial estimated axial force computation circuit.

Abstract: A method in a vehicle for determining road properties is described. The method includes: acquiring vehicle acceleration in x, y and z directions; acquiring a rack force; acquiring a wheel speed for each of all four wheels; determining a wheel speed energy based on the wheel speed; determining a wheel slip of all four wheels of the vehicle based on a respective wheel speed of the wheel; determining an acceleration energy in each of the x, y and z-directions based on the vehicle acceleration and the vehicle speed; determining a rack force energy based on the detected rack force; and determining road properties based on the wheel speed energy, rack force energy and vehicle speed. A system is also described for performing the method.