Abstract: A rotational angle sensor used in an electric power steering apparatus detects a rotational angle of a motor shaft at a portion on a steering system side, as a motor rotational angle (?m). A MPU sets a base correction amount (???m) based on a q-axis actual current value (Iq). The MPU sets a rotational angle correction amount (??m) used to correct the motor rotational angle (?m) by decreasing the base correction amount (???m) as a rotational angular speed (?) increases and by increasing the base correction amount (???m) as a torque differential value (dT/dt) increases.

Abstract: In a gearbox for use in an electric power assisted steering system comprises a housing, an input shaft located at least partially within the housing which carries a worm gear and includes means for coupling to a motor rotor at one end, an output shaft located at least partially within the housing which carries a wheel gear, and a first bearing means which supports the input shaft at a side of the worm distal from the end of the shaft which connects to the motor rotor and second bearing means which supports the input shaft at the other side of the worm, the invention comprises further providing a first biasing means adapted to apply an axial load to the input shaft to bias the axial clearance in the second bearing, the second biasing means acting upon a part of the first bearing means; and a second biasing means adapted to apply a radial load to the input shaft to bias the worm into engagement with the wheel gear, the second biasing means also acting upon a part of the first bearing means.

Abstract: A vehicular steering apparatus according to the invention includes a steering angle correction mechanism, a steering power assist mechanism, and a controller. The steering angle correction mechanism works to provide a correction steering angle to a steerable road wheel of a vehicle. The steering power assist mechanism is configured to provide the steerable road wheel of the vehicle with a base assist power and a correction assist power in a first operation mode and the base assist power and a limited correction assist power in a second operation mode. The controller works to control the steering angle correction mechanism to provide the correction steering angle to the steerable road wheel. The controller also works to control the steering power assist mechanism to operate in the first operation mode if the absolute value of the correction steering angle is greater than a predetermined value and in the second operation mode otherwise.

Abstract: In an electric power steering system for a vehicle that controls a force that urges a steering wheel toward a neutral position thereof, a control unit (21) for the system is configured such that an electric motor (9) for providing an assisting force produces a relatively large returning force when a rotational direction of a steering wheel (2) agrees with a direction of the steering torque applied to the road wheel (7), and a relatively small returning force when a rotational direction of the steering wheel disagrees from a direction of the steering torque applied to the road wheel. Thereby, the effort required for a vehicle operator to steer the vehicle is reduced and the steering feel can be thereby and otherwise improved while providing a favorable returning force that urges a steering wheel toward a neutral position.

Abstract: A magnestostrictive torque sensor 10 detects rotating torque applied to a rod-shaped rotating shaft 11 to work around the rotating shaft based on a change in magnetic characteristics of a magnetostrictive film formed on a surface the rotating shaft so as to extend around a full circumference thereof in a circumferential direction. The magnetostrictive film 14 is formed continuously in an axial direction at a portion on the rotating shaft in the axial direction thereof. The magnetostrictive film 14 has on the continuously formed area a first magnetostrictive film portion 14A and a second magnetostrictive film portion 14B having magnetic anisotropies which are opposite to each other and a third magnetostrictive film portion 14C which is formed between the first and second magnetostrictive film portions.

Abstract: An approved apparatus (10) for turning steerable wheels (14,16) of a vehicle includes a pinion (28) which is disposed in meshing engagement with a rack portion (32) of a steering member (12). A steering column (22) is connected with a pinion (28) and with a vehicle steering wheel (20). A ball nut assembly (38) is connected with an externally threaded portion (36) of the steering member (12). A first motor (72) is connected with the steering column (22) at a location between the pinion (28) and steering wheel (20). A second motor (48) is connected with the ball nut assembly (38). A closed loop assembly (60) may be provided to control operation of the first motor (72). An open loop assembly (82) may be provided to control operation of the second motor (48).

Abstract: A microcomputer is provided with an extracting section capable of extracting a specific frequency component from an input signal. The extracting section extracts, from a pinion angle corresponding to a signal indicating the state of a steering system, a frequency component corresponding to a vibration that increases generation of a rattling noise in a speed reducing mechanism. The extracting section outputs an effective value of the extracted frequency component as a power spectrum. If the power spectrum output from the extracting section is equal to or more than a predetermined threshold value, the microcomputer outputs a motor control signal to reduce the assist force generated by the EPS actuator.

Abstract: An electric power steering apparatus and control device integrated-type electric motor includes an electric motor driving circuit constituted by a plurality of semiconductor power elements and controlling electric power supplied to an armature winding of an electric motor, a switch device for opening and closing a connection between an input terminal of the electric motor driving circuit and an external power source, and another switch device for opening and closing the armature winding, wherein at least one of both the switch devices is constituted by a semiconductor switch element, and the power elements and the semiconductor switch element are mounted on a board attached to a metallic case.

Abstract: Provided is a power steering apparatus capable of suppressing an abrupt change in steering force and preventing a deterioration in steering feeling even in the event of a transition from power steering to manual steering. The power steering apparatus includes a torque sensor, a motor of a permanent magnet field type, and a controller having a motor driving unit and an abnormality monitoring unit, for controlling the driving of the motor. The motor driving unit includes an inverter for driving the motor, and a drive signal generating unit for calculating a target current caused to flow through the motor and outputting a drive signal of the inverter based on the target current. The abnormality monitoring unit includes an abnormality processing unit for constituting a closed-loop circuit including the motor in stopping the driving of the motor.

Abstract: A steer-by-wire system is provided with a driver operating unit, a turning unit, a backup mechanism, a steering reaction actuator, a wheel turning actuator and a controller. The backup mechanism mechanically connects the driver operating unit to the turning unit via a first shaft to transmit an input torque from the driver operating unit to the turning unit when the driver operating unit and the turning unit are mechanically connected by the backup mechanism. The steering reaction actuator applies a steering reaction torque to the driver operating unit. The wheel turning actuator applies a wheel turning torque to the turning unit via a second shaft. The controller controls the wheel turning actuator and the steering reaction actuator. The controller is configured to control the steering reaction actuator based on an operating parameter of the wheel turning actuator.

Abstract: A wheeled vehicle (10) has a power steering assembly. The vehicle can operate in an AWD mode and a 2WD mode. The degree of steering assist provided by the power steering assembly is determined from one of various steering maps (8A-8D; 114A-D). The steering map is selected based on whether the vehicle is operating in the AWD mode or the RWD mode and on a steering mode selected by a steering mode control switch (100) on the vehicle. A method of controlling a power steering assembly is also disclosed.

Abstract: A traction control system (30) for a machine (10) includes a driven wheel (22) operated by a motor that is controlled by an electronic controller (54). A speed sensor (44) measures the speed of the driven wheel (22), and communicates a wheel (22) speed to the electronic controller (54). A travel speed sensor (44) measures the travel speed of the machine (10) and communicates it to the electronic controller (54). A steering sensor (44) measures a displacement of the machine (10)'s steering system (28), and communicates a steering angle to the electronic controller (54). The electronic controller (54) calculates a speed ratio, based on the wheel (22) speed and the travel speed, and an expected slip ratio, based on the steering angle. The speed ratio is corrected by application of the expected slip ratio to yield a corrected speed ratio that is indicative of a slip condition. The operation of the motor is then adjusted to address the slip condition.

Abstract: A motor rotation angle detection device includes a resolver which detects a rotation angle of a motor generating an assist torque for steering road wheels. The resolver includes an annular rotor disposed inside an annular stator with an air gap interposed in between an outer circumferential surface of the rotor and an inner circumferential surface of the stator, so that the stator and the rotor are rotatable relative to each other. A rotor supporting member is connected to a rotary shaft of the motor, and the rotor extends out from an axial end portion of the rotor supporting member so as to surround an outer periphery of the rotary shaft. With the described motor rotation angle detection device, it is possible to stabilize the magnetic permeability of the rotor, and accordingly to increase an accuracy with which the rotation angle of the motor is detected.

Abstract: An object of the present invention is to reduce the possibility of a power assistance failure because of the phenomenon that steering assisting power which an electric power steering unit can generate is lower than the steering assisting power which is required for the electric power steering unit. A vehicle steering control device comprises an electric power steering unit, a steering ratio varying unit which drives an output member relative to an input member driven by steering operation of a driver to vary a steering ratio, and a control means which controls the steering ratio varying unit.

Abstract: A vehicle steering apparatus utilizing SBW capable of downsizing an expensive turning-power motor, in which a steering mechanism 20 provided with a steering wheel 21 maneuvered by a driver is mechanically separated from a turning mechanism 30 for turning road wheels 35, 35. A turning-power motor 45 of the turning mechanism 30 turns the road wheels 35, 35 based on a turning angle-steering angle ratio determined by a control portion 66 of a controller 61 in accordance with a vehicle speed of the vehicle. The turning angle-steering angle ratio increases with increasing vehicle speed until the vehicle speed reaches a predetermined value from zero; while when the vehicle speed is higher than the predetermined value, the turning angle-steering angle ratio decreases with increasing vehicle speed.

Abstract: In an electric power steering system, when a motor rotation angular speed ? and a motor rotation angular acceleration ? of a steering assisting motor both exceed corresponding predetermined values ?s and ?s, respectively, an abnormal external force application-determining section determines that an external force equal to or greater than a predetermined value is applied to a steering mechanism, and sets an abnormal external force application determination flag (FLG) to 1. When the abnormal external force application determination flag (FLG) is 1, a d-axis electric current command value-calculating section activates a motor rotation angular speed-reducing section and performs field-strengthening control based on a motor rotation speed/d-axis electric current command value map.

Abstract: An alignment changing control device that includes: a motor drive section which adjusts electrical power supplied to a motor of the electric actuator according to an operation command and, when receiving an operation inhibiting signal, limits or stops supplying the electrical power to the motor; a motor temperature estimating section for calculating an estimated temperature of the motor from at least a current supplied to the motor, an outside air temperature and a vehicle speed, based on heat balance relationship; and a comparator which transmits the operation inhibiting signal to the motor drive section when the estimated temperature of the motor calculated by the motor temperature estimating section is higher than a predetermined temperature, which is equal to or lower than an operation allowable temperature of the motor.

Abstract: A vehicle steering apparatus 1 includes an EPS actuator 17 and an EPS ECU 18 that controls the EPS actuator 17. The EPS actuator 17 applies an assist force that assists a steering operation. A microcomputer 43 of the EPS ECU 18 determines whether the currently executed oversteer control (OS control) is being intensified or converged. In the OS control intensification state, in which the vehicle stability is low, the microcomputer 43 reduces a damper compensation current command Idp* (Idp**), which is a damper compensation component for attenuating a steering wheel turning speed ?s.

Abstract: A motion-control system includes an operator interface with an operator-input member and a controllable force feedback device drivingly connected to the operator-input member. The motion-control system may also include controls that regulate the motion of one or more moveable components, including adjusting a first operating parameter in a manner that depends at least in part on a control error between a target value of a second operating parameter and an actual value of the second operating parameter. The target value of the second operating parameter may be based at least in part on the motion of the operator-input member. The controls may also operate the controllable force feedback device to provide feedback force on the operator-input member in a manner that depends at least in part on the control error and such that the derivative of the feedback force with respect to the control error varies dependent at least in part on the control error.

Abstract: A steering column assembly includes a column jacket extending along a longitudinal axis and a steering shaft rotatably supported by the column jacket. A power assist module includes a housing coupled to the column jacket and a motor. The motor applies a torque to the steering shaft. An isolator connection interconnects the housing and the column jacket to permit rotational flexure of the power assist module relative to the column jacket, i.e., the power assist module may rotate relative to the column jacket, thereby preventing undesirable rotation of a lever mounted to the column jacket in response to the motor applying the torque to the steering shaft.

Abstract: An electric motor (7) is driven with high output at the time of low-speed running, and a steering at a high resolution is enabled at the time of fast-speed running. An electric power steering device (1) causes the electric motor (7) to generate auxiliary torque in accordance with the largeness of steering wheel torque by the steering operation of a wheel (9) made by a driver and reduces the steering wheel torque to the driver. A control device (10) drives, based on a vehicle-speed signal (Vs) from a speed sensor (11), the electric motor (7) with high output at the time of low-speed running, and enables steering at a high resolution at the time of fast-speed running without increasing an electric-motor output. Moreover, large steering wheel torque is requisite at the time of low-speed running, and a steering at a high resolution is requisite at the time of fast-speed running. Accordingly, this does not affect the steering feeling to the driver.

Abstract: A method for retrofitting an electric power steering system for a vehicle, the electric power steering system comprising a torsion bar and a controller configured to facilitate steering control based at least in part on a deflection or a strain of the torsion bar, is provided. The method includes the steps of obtaining the electric power steering system, and reconfiguring the controller so as to be further configured to at least facilitate adjusting a stiffness of the torsion bar based at least in part on a parameter pertaining to operation of the vehicle.

Abstract: A vehicular steering control apparatus is comprised of a steering system of receiving a steering torque inputted by a driver, a torque control actuator connected to the steering system to produce an actuator torque relative to the steering torque and a steering controlling section connected to the torque actuator. The steering controlling section controls the torque control actuator and increases a phase delay of the actuator torque relative to the steering torque toward a neighborhood of 180° as the frequency of the inputted steering torque increases.

Abstract: A steering system including a pair of operating members operable independently of each other, wherein a target wheel-turning amount and a return force for returning operating members to their reference position are determined based on an operation amount of the operating members. At least either a steering gain, set for each pair of operating members upon determination of the target wheel-turning amount, or a return-force gain, set for each pair of operating members upon determination of the return force, is made changeable depending on various parameters. Steering characteristics can be set relatively freely. For example, where the steering gain is made changeable depending on an operating angle of the operating member, determination of the target wheel-turning amount can be made with a changeable degree of contribution of operation of each operating member, which is changeable depending on an operating position of the operating member.

Abstract: An electric power steering apparatus including a steering angle detection part that detects a steering angle of a steering wheel and outputs a steering angle signal, a steering control unit that controls a motor to give an assist torque to the steering wheel, an abnormality detection part that determines an abnormality of the steering angle detection part, and a motor angle detection part that detects a rotational angle of the motor. The steering control unit calculates a steering angle information based on at least the steering angle signal, and includes a signal storage part that stores the steering angle information. The steering control unit runs the motor continuously when the abnormality detection part detects the abnormality of the steering angle detection part until a vehicle stops or until the abnormality detection part determines that the steering angle signal returns to a normal state from the occurrence of the abnormality.

Abstract: An electric power assisted steering apparatus for a vehicle, comprising: a steering mechanism, which operatively connects a steering wheel to road wheels of the vehicle; an electric motor operatively connected to the steering mechanism; a torque sensing means adapted to produce a first output signal indicative of the torque carried by a portion of the steering mechanism; a vehicle speed sensing means for producing a second output signal indicative of the speed of the vehicle; a signal processing means adapted to receive the first and second signals and to produce a torque demand signal representative of the torque to be applied to the steering mechanism by the motor; and a motor drive stage adapted to provide a drive current to the motor responsive to the torque demand signal; wherein the apparatus include at least one of the torque limiter arranged to limit the torque and the maximum rate of increase of the torque following a restart of the apparatus, the limit and rate being determined at least in par

Abstract: There is provided a steering apparatus including a pinion communicating with an operation of a steering member, a rack shaft having a rack meshed with the pinion, and a support yoke resiliently coming into contact with the rack shaft, and being configured to convert rotation of the pinion into movement of the rack shaft in an axial direction in a meshing portion in which the pinion and rack mesh to each other. The steering apparatus comprises a detection unit for detecting a force applied to the support yoke to which a force acting on the meshing portion being transmitted from the rack shaft and a calculation unit for calculating a steering torque applied to the steering member based on the force detected by the detection unit, wherein the pinion and the rack are formed in helical gears.

Abstract: When stopping operation of an electric power steering apparatus, a motor relay is kept in an on-state even after a power supply relay is in an off-state. A drive control portion sets a target value of a d-axis current to a value other than zero and sets a target value of a q-axis current to zero, and performs a processing same as that at the time of rotating a motor. MOS-FETs contained in a motor driving circuit are controlled such that each of driving currents of the two phases or more is not zero and the brushless motor does not rotate even supplied with these driving currents. Electric charge accumulated in a capacitor is discharged via the MOS-FETs each in an on-state, a motor relay and the windings of the brushless motor. The electric charge accumulated in the capacitor may be discharged via the excitation coil of the motor relay.

Abstract: An electric power steering apparatus includes: a torque sensor including a first sensor element and a second sensor element; a control unit; and a motor. When the first sensor element and the second sensor element are both normal, the first sensor output that is output by the first sensor element and the second sensor output that is output by the second sensor element have a predetermined correlation corresponding to a steering operation performed by a driver. When the first sensor element or the second sensor element is abnormal, the control unit executes weighting with respect to the first sensor output and the second sensor output and calculates a steering torque on the basis of the weighted first sensor output and the weighted second sensor output. The motor generates a steering assist force on the basis of the steering torque.

Abstract: A steering assisting system has a variable transfer ratio steering apparatus and an electric power steering apparatus. The variable transfer ratio steering apparatus has an electric motor for a rotation transfer ratio varying operation. When a predetermined failure occurs in the electric power steering apparatus, the motor is driven to assist the steering operation of the steering wheel. Therefore, without providing the electric power steering apparatus in two sets, the power-assisting torque generation can be continued even when the electric power steering apparatus fails to generate the power-assisting torque.

Abstract: A motor for an electric power steering device with an integrated controller (1) includes a motor (2) and a controller (15) which controls driving of the motor (2) and has a metal case, the motor and the controller being formed integrally with each other. The motor (1) is attached to a speed reduction mechanism (23). The motor (2), the controller (15), and the speed reduction mechanism (23) are arranged in this order, in an axial direction, and in substantially coaxial relation with each other. The heat emitted from a driving substrate and the motor can be efficiently transmitted to the speed reduction mechanism.

Abstract: A method, system, and computer program product for calculating a torque overlay command in a steering control system is provided. The method includes receiving a current hand wheel angle, receiving a change in vehicle yaw moment command, and calculating a lateral force in response to the change in vehicle yaw moment command. The method also includes determining a new tire side slip angle from the lateral force and calculating a commanded hand wheel angle from the new tire side slip angle. The method further includes calculating an error signal as a difference between the commanded hand wheel angle and the current hand wheel angle, and generating a torque overlay command from the error signal.

Abstract: An electric power steering apparatus includes a driving target value setting unit for setting a driving target value of an electric motor; a steering acceleration detecting unit for detecting or estimating a steering acceleration; a correction amount computing unit for computing a control correction amount in accordance with the steering acceleration; a vehicle acceleration detecting unit for detecting an acceleration of a motor vehicle; an acceleration adaptive gain setting unit for setting a gain in accordance with an acceleration of a motor vehicle; a multiplication unit for determining a gain adjusted control correction amount by multiplying the control correction amount with the acceleration adaptive gain; a correcting unit for correcting the driving target value on the basis of the gain adjusted control correction amount; and motor driving units for driving the electric motor on the basis of the corrected driving target value.

Abstract: An electric power steering control apparatus for controlling a motor that provides an assisting force for steering a steering wheel has a command value calculation device operable to calculate a command value for a torque current to be fed to the motor based on a steering torque of the steering wheel, a magnetic field control device operable to control intensity of a magnetic field in the motor, and a motor drive device operable to drive the motor based on outputs from the command value calculation device and the magnetic field control device. The magnetic field control device is operable to perform a field weakening control for weakening the magnetic field in the motor when a vehicle speed is less than a predetermined value, and to not perform the field weakening control when the vehicle speed is not less than the predetermined value.

Abstract: A power steering system, which is disposed in the forward part of a vehicle, allows an electric motor to boost the steering torque applied by a driver, and transmits the steering torque to wheels via a steering transmission mechanism. The power steering system includes an impact detection device that detects the impact of an object on a rack housing that houses a rack bar constituting the steering transmission mechanism to detect the impact on the power steering system more accurately.

Abstract: An electric power steering apparatus in which, when an abnormality is generated in an electric power steering apparatus, an assist is reduced smaller than normal when a steering burden is estimated to be small; and the assist can be increased to normal and the steering burden can be sufficiently reduced when the steering burden is estimated to be large. When an abnormality is detected, an assist command is set smaller than at a normal time when there is no abnormality in a first range where the steering burden estimated by the steering burden estimation unit is small; the assist command is increased to that at a normal time in a second range where the steering burden estimated by the steering burden estimation unit is larger than the first range; and an assist torque of a motor is controlled in response to the assist command at the abnormal time.

Abstract: In an electric power steering apparatus, steering torque of a steering wheel is detected by a torque sensor, and a motor 10 for generating steering assist power is controlled so that the steering assist power is generated according to a basic assist torque corresponding to the detected steering torque. A correspondence relationship between the steering torque and the basic assist torque is set such that an assist gradient that is a rate of change of the basic assist torque to the steering torque varies according to variation of the steering torque. A correction amount of an output of the motor 10 varies according to the variation of the assist gradient.

Abstract: A method for determining the steering ratio of a vehicle from sensed measured values (e.g., yaw rate, steering wheel angle, vehicle speed) in a manner that takes vehicle parameters (e.g., self-steering gradient, wheelbase and other vehicle dimensions) into consideration during stable travel of the vehicle.

Abstract: A magnetostrictive torque sensor includes a rotatable shaft rotatably supported by bearings, a magnetostrictive film disposed on the surface of the rotatable shaft, and a detecting coil that detects a change in a magnetic property of the magnetostrictive film. A hollow cylindrical ring is press-fitted over and fixed to the rotatable shaft near the magnetostrictive film, for example, near the right end of the magnetostrictive film.

Abstract: An electronic control unit inputs a side slip angle ? of a vehicle body. The unit calculates a dynamic zero point ?o for reducing a lateral force generated in the vehicle due to the side slip angle ? of the vehicle body. The unit calculates a steering angle ?a, which is represented by the difference between the dynamic zero point ?o and a steering angle ? detected by a steering angle sensor. The unit calculates a reaction torque Tz having a predetermined relation with the steering angle ?a. The unit drives and controls an electric motor to generate the calculated reaction torque Tz. Thus, the unit guides a driver to a proper steering-wheel rotating direction.

Abstract: In a motor controller, if a failed electric current flow in any one of phases of a motor is detected, a motor control signal is generated, based on a phase other than the phase with the failed electric current flow, in such a manner that a motor electric current matches a required torque except for at a specific rotation angle corresponding to the phase with the failed electric current flow.

Abstract: In a steering system for a vehicle incorporated with a rear drive electric motor (5) for driving a pair of rear wheels (3rl, 3rr) that can function as a regenerative brake for the rear wheels, a steering torque control unit (38) reduces a steering assist torque provided by the power steering assist unit (21) when the rear drive electric motor is providing a regenerative braking. When the rear wheels are braked by a regenerative braking action without substantially applying a brake to the front wheel, the vehicle may acquire a temporal oversteer tendency. However, by increasing the effort required to steer the front wheels, such a tendency can be canceled or compensated, and the vehicle operator is enabled to control the vehicle without experiencing any unfamiliar feeling or discomfort. The effort required to steer the front wheels can be increased by decreasing the assist steering torque or providing a reactive steering torque at such a time.

Abstract: A plurality of magnetic pole bodies, provided on a stator of a steering motor, are divided into two electrically independent groups. Each group includes i) six magnetic pole bodies that are arranged in succession and ii) a corresponding number of magnetic pole bodies arranged opposing those six magnetic pole bodies. The two groups vibrate only slightly when operating normally. However, if one of the groups fails, vibration of the stator from elastic deformation in an undulating manner in the circumferential direction will increase, thereby alerting the driver of an abnormality in the steering motor. This increases the likelihood of measures being taken promptly to fix the abnormality in the steering motor, thus improving fail-safe performance.

Abstract: A method is provided for reducing the energy consumption of a motor vehicle having an internal combustion engine and at least one vehicle electric system, to which at least a first electric consumer is connected. In order to achieve an efficient vehicle electric system with a reduced energy consumption, the internal combustion engine is operated in a first operating mode at a first speed. In a second operating mode, the internal combustion engine is operated at a second speed that is higher than the first speed. A driving situation detection device provided in the vehicle recognizes an imminent specific driving situation on the basis of the previous behavior of the driver in controlling the vehicle and/or the behavior of the vehicle in advance, and initiates a switch in the internal combustion engine from the first operating mode to the second operating mode.

Abstract: A method for determining a steering angle of a steering shaft in a motor vehicle is disclosed. The method uses a rotation sensor associated with an electric motor of a power steering system to determine the relative steering angle of the steering column. The relative steering angle is measured relative to an initial position of the steering column during vehicle startup. The relative steering angle is reset each time the motor vehicle is turned on.

Abstract: A steering system for a vehicle is disclosed. The steering system includes variable gear ratio steering apparatus, a first ECU for controlling the apparatus, an electric power steering apparatus, a second ECU for controlling the apparatus, The steering system further includes a steering wheel angle sensor and a steering wheel angle ECU, which are integrated. The steering wheel angle sensor detects a steering wheel angle of a steering wheel. The ECU calculates an estimation value of the steering wheel angle of the steering wheel and compare between the estimation value and the detected value of the steering wheel angle. Thereby, the ECU performs a process of determining detection accuracy of the steering wheel angle sensor.

Abstract: An electric steering system includes a device for measuring a steering input into a steering system; a device for measuring a steering speed; a section for computing a target current based on the steering input; and a control section for applying a steering power to the steering system by driving a motor according to the target current, and applying damping to the steering system based on the steering speed. A rate of increase in a damper gain defined when the steering speed is equal to or greater than a predetermined value is higher than that defined when the steering speed is less than the predetermined value, or the damper gain defined when the steering speed is equal to or greater than a predetermined value has a constant value increased in a step form from values of the damper gain defined when the steering speed is less than the predetermined value.

Abstract: An electric power assisted steering assembly comprises a steering mechanism which operatively connects a steering wheel to the road wheels of a vehicle, a torque sensing means which is adapted to produce an output signal indicative of the torque applied to a portion of the steering mechanism by the driver, a signal processing means which is adapted to control the motor so as to cause the motor to apply a torque to the steering mechanism to assist the driver, and a compensation torque generating means which is adapted to combine a torque value representative of the motor applied torque with the output of the torque sensor to produce a compensation torque signal that is to be applied by the motor to the steering mechanism that at least partially compensates for any pull on the steering due to suspension misalignment.

Abstract: An electrically driven power steering system for a vehicle comprises a steering sensor for detecting a steering operation of a steering wheel and a power steering control unit, which receives a command signal from a vehicle movement total control unit, calculates a target steering assist torque from a steering signal from the steering sensor and the command signal and drives a steering assist electric motor in accordance with the above calculated target steering assist torque. The power steering control unit further calculates a feasible torque to be generated at the steering assist electric motor, and drives the steering assist electric motor at the feasible torque, when the feasible torque is lower than the target steering assist torque, namely when a driving current to the electric motor should be limited due to an increased temperature of the electric motor and so on.

Abstract: To suppress temperature rises of an electric power steering device provided at a vehicle equipped with a diff lock device and to restrict the operation of the electric power steering device at times other than during diff locking. An electric power steering device that is coupled to a steering shaft fitted with handlebars at an upper end and that generates auxiliary force that supplements the steering force, and a diff lock unit that selects a differential state and a non-differential state (diff lock) of a differential device are provided. An ECU reduces the maximum value of the auxiliary force generated by the electric power steering device to a prescribed limit value when the diff lock is detected by the diff lock sensor is also provided. The ECU releases limiting of the maximum value of the auxiliary force when release of the diff lock is detected by the diff lock sensor.