Abstract: An electric power steering system includes a steering wheel, a rack-and-pinion type steering gear box connected to the steering wheel, a steering torque sensor, a pinion shaft, and a steering actuator mounted on the pinion shaft to assist a steering operation conducted by a driver. An overload preventing control is conducted so that a sum of a torque conversion value of an assist current and a steering torque detected by the steering torque sensor equal a predetermined threshold value. When the steering gear box has reached a stroke end, and the assist current or the steering torque is smaller than a predetermined threshold value, the overload preventing control is conducted using a threshold value that is less than the predetermined threshold value.

Abstract: In an electric power steering system, an electric motor generates output power for power-assisting steering operation of a steering wheel, a torque sensor generates a plurality of electric output signals corresponding to a torque applied to the steering wheel, and a control unit controls the steering operation of the electric motor in accordance with at least one of the electric output signals of the torque sensor. The control unit detects a difference between rotation speeds of left and right steered wheels, checks whether any one of the plurality of output generating parts is in failure, and specify a failing-device based on the rotation speed difference and the plurality of output signals.

Abstract: An an electric power steering device which, when an abnormality occurs in one phase of a three-phase brushless motor, permits continuous driving of the motor using the remaining two phases without deteriorating the steering feeling. When a power distribution abnormality of a drive system of one phase of respective phase coils has been detected by an abnormality detection section, an abnormal-time phase current instruction value for using the remaining two phase coils is calculated based on a steering assist electric current instruction value, and an electric motor is driven based on that abnormal-time phase current instruction value. At that time, when an electrical angle falls within an acceleration region, the abnormal-time phase current instruction value is increased or decreased for correction in order to accelerate rotation of the three-phase brushless motor in a steering direction.

Abstract: A booster circuit of a motor drive apparatus has at least two sub-booster circuits connected in series. Each sub-booster circuit includes a booster coil, a boosting switching element, a reducing switching element and an output capacitor, and outputs, by boosting an input voltage, a boosted output voltage. The booster circuit 20 outputs from its final stage sub-booster circuit a booster output voltage, a total boosting ratio of which is a product of sub-boosting ratios of the series-connected sub-booster circuits. Thus, the booster output voltage supplied to a motor drive circuit is prevented from falling even when high power output is required.

Abstract: A vehicle steering apparatus 1 includes a variable gear ratio actuator 7, an IFS ECU 8, which controls the actuator 7, an EPS actuator 17, and an EPS ECU 18, which controls the EPS actuator 17. The variable gear ratio actuator 7 varies the transmission ratio between a steering wheel and steered wheels. The EPS actuator 17 applies an assist force that assists a steering operation. A microcomputer 43 of the EPS actuator 17 increases an inertia compensation current command Iti* (Iti**), which is a compensation component based on the differential value of a steering torque, during actuation of the variable gear ratio actuator 7, that is, when an ACT angle ?ta is changed.

Abstract: A motor controller capable of detecting an oscillation of a feedback loop and performing gain adjustment while updating a gain value of a control unit is provided. The motor controller includes an electric motor, an operation-amount detector, a control unit, a machine, a disturbance signal generator which generates a sweep sine wave, a compensation-driving-force detector, a vibration calculator, an oscillation detector, a vibration storage, a simulated open-loop gain calculator, a gain changer, and an automatic gain changer, and detects an oscillation by processing a response signal in time series on the basis of a first threshold regarding to a magnitude of vibration and a second threshold regarding a frequency.

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.

Abstract: The invention provides a motor-driven power steering apparatus provided with a fault diagnosing apparatus diagnosing a fault of a board temperature detecting apparatus on the basis of an armature current Im detected by a motor current detecting apparatus and a board temperature Tb of the control board detected by the board temperature detecting apparatus, and a target current suppressing apparatus suppressing a target current Iq at a time when the fault diagnosing apparatus diagnoses that the board temperature detecting apparatus is out of order.

Abstract: A steering device includes: a main body mounted on an electric vehicle; a pivot axle unit mounted rotatably to the main body and having opposite rod portions extending outwardly and respectively from opposite lateral sides of the main body; a control unit coupled to the pivot axle unit for generating a control signal associated with forward or rearward movement of the electric vehicle in response to rotation of the pivot axle unit relative to the main body; and an operating unit operable to drive rotation of the pivot axle unit and including two mounting members that are connected respectively to the rod portions of the pivot axle unit, and a connecting member interconnecting the mounting members. Each mounting member has radially extending operating rods.

Abstract: A control device for the active steering of a vehicle comprising a driving differential that is positioned between a steering wheel and steering control means, said differential which furthermore receives at a first input a counter-steering command supplied by a turn correction motor, wherein said steering wheel is linked to a second input of said differential by non-return means preventing any force feedback from said differential to said steering wheel.

Abstract: In a steer-by-wire steering control device for a vehicle using a model following control based on yaw rate or lateral acceleration, the target steering angle(s) of front wheels and/or rear wheels (Sfbs, Srbs) are corrected according a roll rate (Rre) of the vehicle which may be either detected or estimated from a lateral acceleration or yaw rate. Thereby, the roll rate gain can be reduced, and the damping property and response property of the yaw rate can be improved.

Abstract: It is one object of the present invention to provide a steering device for a vehicle improving a resolution of detecting a steering reaction force thereby to control precisely a reaction actuator and to improve a steering feeling. The steering device for the vehicle is equipped with a reaction actuator 19 acting a steering reaction force on a steering wheel 1. This device further includes a steering angle sensor 11 detecting a steering angle ?h of the steering wheel 1, a controller 20 controlling the reaction actuator 19 according to the steering angle ?h, a torque sensor 12 detecting a steering torque Th acted on the steering wheel 1. The controller 20 controls in a feedback way the reaction actuator 11 based on the steering torque Th in a predetermined range including a middle point of the steering angle. The controller 20 drives, in a open-loop way without feed-backing the steering torque Th, the reaction actuator 19 out of the predetermined range of the steering angle ?h.

Abstract: A microcomputer 17 (signal generating section 24) includes an attenuating section 31, which attenuates a specific frequency component included in an input signal. The attenuating section 31 receives a d-axis current value Id and a q-axis current value Iq, which are actual currents supplied to a motor 12. The attenuating section 31 receives a rotational angular velocity ?e of the motor 12. The attenuating section 31 changes the specific frequency component to be attenuated based on the input rotational angular velocity ?e. Then, the microcomputer 17 executes current feedback control for feeding power to the motor 12 based on the d-axis current value Id? and the q-axis current value Iq? that have been attenuated.

Abstract: A u-MDPS (United Motor Driven Power Steering) system includes one MDPS motor, one MDPS ECU that assists steering force using power of the MDPS motor, and has a logic implementing tilting-up/down and telescopic movement, and a multi-function generator that switches a power transmission path of the MDPS motor to the steering path for assisting a steering force, the tilt path for tilting up/down a column tube, or the telescopic path for facilitating a telescopic movement of the column tube. The multi-function generator may include a motor power converting unit, a motor power transmitting unit and a tilt•telescopic motion unit. The tilt•telescopic motion unit further includes an electromagnetic clutch, which makes it possible to implement fail-safety function by switching to a lock-manual mode of one MDPS motor.

Abstract: A vehicular steering control apparatus has a steering direction control device and a reaction force application device. The steering direction control device controls a steering angle of steered wheels by controlling a steering direction control motor based on a steering wheel angle. The reaction force application unit is provided more closer to a steering wheel than the steering direction control device is and has a differential reduction unit and a reaction force application motor. The differential reduction unit transfers rotation of an input shaft to an output shaft. The reaction force application motor drives the differential reduction unit. The steering wheel and the steered wheels are normally linked mechanically, so that no fail-safe device is needed.

Abstract: An electronic control unit receives a detection value from each sensor, and determines a familiarity degree coefficient indicating the degree of driver's familiarity with steering characteristics, using the received detection values. When the coefficient has a value near “0”, a desired actual steering angle is calculated to be a small value, and when the coefficient has a value near “1”, a desired actual steering angle is calculated to be a large value. When the coefficient has a value near “0”, a time constant of an actual steering actuator is set to a large value, and when the coefficient has a value near “1”, the time constant is set to a small value. A reaction torque is determined based on the coefficient.

Abstract: A materials handling vehicle is provided comprising: a frame comprising an operator's compartment; wheels supported on the frame, at least one of the wheels being a steerable wheel; a steer-by-wire system associated with the steerable wheel to effect angular movement of the steerable wheel about a first axis; and a control apparatus. The steer-by-wire system comprises a control handle capable of being moved by an operator to generate a steer control signal, a selection switch capable of generating one of a first select signal and a second select signal, and a steer motor coupled to the steerable wheel to effect angular movement of the steerable wheel about the first axis. The control apparatus may be coupled to the control handle to receive the steer control signal, coupled to the selection switch to receive the one select signal, and coupled to the steer motor to generate a first drive signal to the steer motor to effect angular movement of the steerable wheel about the first axis.

Abstract: In an electric power steering system (10) for use in a vehicle incorporated with a vehicle behavior control system (30), a failure detecting unit (12) detects a failure of the electric power steering system according to the steering torque and actual electric current. A criterion for detecting a failure by the failure detecting unit is changed when the vehicle behavior control system is activated. Thereby, even when the vehicle behavior control system is activated and it causes a corrective current to be supplied to the electric motor, because the failure detection criterion is changed, the failure detecting unit is prevented from confusing the corrective current due to the operation of the vehicle behavior control system with an erroneous current caused by a failure of the electric power steering system. Therefore, an unnecessary interruption of the operation of the electric power steering system can be avoided, and the convenience of the electric power steering system can be enhanced.

Abstract: There is provided a control apparatus that controls a motor of an electric power steering system to assist a steering effort of an operator. The control apparatus includes a sensor, a parameter computer, a difference computer, a target torque computer, and a motor driver. The parameter computer computes a current value of one of physical parameters of one of constituents of the electric power steering system based on a steering parameter determined by the sensor referring to an equation of motion. The difference computer computes a difference between the current value of the one of the physical parameters computed by the parameter computer and a predetermined value of the one of the physical parameters. The target torque computer computes a target torque of the motor which compensates for the difference between the current value and the predetermined value of the one of the physical parameters.

Abstract: In a steering control unit, a U-phase feed line branches into paired branch feed lines, phase-open MOSFETs are provided in middle portions of the branch feed lines, phase-open MOSFETs are provided in middle portions of a V-phase feed line and a W-phase feed line, and the phase-open MOSFETs are arranged in such a manner that parasitic diodes are in the same orientation with respect to a motor. When an abnormality occurs, all the phase-open MOSFETs are turned off. Then, a closed circuit, which includes phase coils and through which electric currents flow, is no longer present.

Abstract: A method for controlling an assisted steering maneuver in an electric power steering (EPS) system includes modeling steering dynamics during a torque overlay operation to generate a dynamic steering model (DSM), measuring vehicle operating values, and detecting a driver intervention in the torque overlay operation based on the DSM and the vehicle operating values. The torque overlay operation is overridden when driver intervention is detected, allowing the driver to regain control of the steering maneuver. A vehicle includes a steering wheel, a steering assist mechanism, and an EPS system having an electronic control unit (ECU) adapted to determine a present intent of a driver of the vehicle to interrupt application of the TOC based on a vehicle operating value transmitted by the driver to the steering wheel. The ECU is operable for interrupting the torque overlay operation when the present intent of the driver is determined.

Abstract: A steering control system is connectable to a motor configured to control a steering and a LAN (Local Area Network) and is allowed to receive a control signal for controlling said motor from the LAN is received. The steering control system includes: a motor configured to control a steering; a main calculation unit connectable to the LAN; a motor drive circuit connected to the main calculation unit and configured to drive the motor; a sub calculation unit connectable to the LAN; and a motor drive limiting unit connected to the sub calculation unit and configured to limit a drive of the motor.

Abstract: A steering system of a motor vehicle has a steering wheel which engages a steering rack via a steering pinion of a steering column. A steering torque is exerted by a driver on the steering rack via the steering wheel. A steering torque assistance unit is provided and has an electric drive and a gear stage. A steering assistance torque is able to be exerted on the steering rack via the electric drive of the steering torque assistance unit. The electric drive engages the steering rack via the gear stage. Accordingly, at least one sensor determines by measurement a bearing force acting on a bearing of the steering torque assistance unit, the steering torque assistance unit generating the steering assistance torque in dependence on the steering torque exerted by the driver and in dependence on the bearing force determined by measurement.

Abstract: To estimate a fluctuation component of the torque generated at the motor accurately, a motor control device (3) which controls a motor with a stator having armature winding and a rotor having a permanent magnet is provided to include a torque fluctuation component estimation unit for estimating a torque fluctuation component generated at the motor based on flux-linkage of the armature winding and an armature current that flows the armature winding. The torque fluctuation component estimation unit estimates the torque fluctuation component (Trp) based on an inner product (Fd·id+Fq·iq) of a flux-linkage vector which is a vectorial representation of the flux-linkage and a current vector which is a vectorial representation of the armature current.

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 controller applies slight rotational torque to a drive gear of a reduction mechanism also in a predetermined range in which a motor does not produce any steering operation assist force. That is, the motor is caused to produce slight rotational torque not enough to drive a driven gear, and the rotational torque direction is reversed under a given condition. Accordingly, a backlash between the drive gear and the driven gear is eliminated.

Abstract: When an electrification failure occurs in any of the phase of a motor, a control device of an electric power steering device executes current control for generating, in each of two electrification phases other than a phase with the electrification failure, a phase current that changes in the form of a secant curve or a cosecant curve based on an asymptotic line, which is a predetermined rotational angle corresponding to the phase with the electrification failure, to thereby continuously output a motor control signal. The control device of the electric power steering device executes current restriction for restricting the phase current within a predetermined range. The control device of the electric power steering device further executes control for accelerating rotation of the motor during two phase drive, in order to prevent the occurrence of a stuck steering wheel during low-speed steering, which is caused as a result of the execution of the current restriction.

Abstract: A system and method for controlling a vehicle steering system, comprising receiving at least one signal corresponding to one or more of a lateral acceleration, a longitudinal acceleration, a vertical acceleration, a suspension travel, and a vehicle speed, calculating or determining an optimum steering rack travel from the at least one signal, and limiting travel of a steering rack of the vehicle based on the optimum steering rack travel.

Abstract: An angular velocity estimate (?e) used in motor control of an electric power steering is obtained as follows. In a first state period during which the motor substantially stops its rotation, a resistance calculation unit calculates a motor resistance value (Rc) on the basis of a detected value (Vm) of motor voltage and a detected value (Im) of motor current. An average calculation unit obtains an average value (Rav) of the calculated resistance values (Rc) in a retained period. A current-resistance characteristic that associates motor current with motor resistance is held in a characteristic holding unit, and a characteristic updating unit updates the current-resistance characteristic on the basis of the average value (Rav). An estimate calculation unit calculates the angular velocity estimate (?e) on the basis of the detected value (Vm) of motor voltage, the detected value (Im) of motor current and a motor resistance value (Rm) obtained from the current-resistance characteristic.

Abstract: An oscillating gear device includes an axially fixed gear piece rotatable around a first axis and an axially oscillating gear piece that oscillates while being inclined with respect to the first axis. A plurality of pins held by one of the gear pieces engage with a plurality of tooth grooves of the other gear piece in engagement regions at a predetermined length in longitudinal directions of the pins. A formula rC0/rF0=ZC/ZF is satisfied, where rC0 is a distance between an arbitrary point on the central axis of the pin in a corresponding section corresponding to the engagement regions of the pin as viewed in the radial direction of the pin and the first axis, rF0 is a distance between the arbitrary point and the second axis, ZC is the number of pins of the one gear piece, and ZF is the number of tooth grooves of the other gear piece.

Abstract: A system for decoupling steering rack force disturbances in electric steering may comprise a steering wheel angle sensor, a yaw rate sensor, a lateral acceleration sensor, and a steering torque sensor. The system may also comprise a tire force generator configured to receive signals from the steering wheel angle sensor, the yaw rate sensor, and the lateral acceleration sensor and send a reference rack force to a controller. The system may further comprise a rack force observer configured to receive signals from the steering torque sensor and send an estimated rack force to the controller, wherein the controller is configured to receive signals from the tire force generator and the rack force observer, compare the estimated rack force with the reference rack force to determine a rack force disturbance, and adjust an auxiliary torque based on the rack force disturbance.

Abstract: Disclosed is a superimposition steering unit in which a steering angle set by the driver can have an additional angle superimposed thereon. The superimposition is caused by individually operable structural components.

Abstract: An electric motor and a control unit are integrally formed and are placed coaxially with a shaft of a gear box for reducing a speed of rotation of the electric motor and also the control unit is placed between the gear box and the electric motor, and a power feeding part of the electric motor is bonded to a bonding part of the control unit inside a housing or a case through an opening part disposed in the housing and/or the case 24.

Abstract: A control unit estimates reverse transfer torque transferred from tires to a steering wheel and calculates an assist gain based on the reverse transfer torque. The control unit calculates basic assist torque demand by multiplying torsion torque detected by a torque sensor by the assist gain. The control unit further calculates assist torque command by adding compensation for stabilization. Since the assist gain is determined based on the reverse transfer torque, actual assist torque is generated in accordance with the force transferred from the road surface. Thus, a driver can operate the steering wheel while feeling the force from the road surface.

Abstract: A method is provided for centering a steering rack in an automotive vehicle, particularly a vehicle that includes an electric power steering (EPS) system. The centering method includes locating a center by using an electric motor of the EPS system. The method includes temporarily locking the steering rack in place and subsequently installing a steering wheel to a steering column. An on-board processor or ECU of the automotive vehicle determines or locates the center of the rack by detecting the first and second ends of the rack when at least one of a velocity of the electric motor reaches zero, a current of the electric motor reaches a preselected level, and steering angle of the electric motor stabilizes. The method monitors potential pinch point zones and reverses turning of the tires upon reaching the pinch threshold level and the automatic centering process is terminated.

Abstract: In a motor-driven steering assist apparatus, a gear train transmitting a rotation of an electric motor to an output shaft comprises a single unit body surrounded by housings, and an attaching boss to a vehicle body side bracket is provided in a lower surface of the housing as seen from an axial direction of the output shaft.

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

Abstract: An electronic control apparatus has a microcomputer including a first CPU and a second CPU configured to perform calculation processing and control processing for a vehicle control device such as a variable gear ratio steering device. The first CPU and the second CPU calculate temporary detection values of an operation amount of an actuator based on a detection signal of a sensor, respectively. The temporary detection values are compared to determine whether the vehicle control device is controllable based on the detection signal of the sensor. Thus, the electronic control apparatus is reduced in size, and calculation results are monitored each other within one microcomputer.

Abstract: An electric power steering system includes a motor that applies assist force to a steering system, and updates a motor resistance (Rm) that is a value indicating a resistance of the motor. Specifically, the motor resistance (Rm) is updated on the basis of the fact that an induced voltage (EX) of the motor is smaller than a first determination value (GA). In addition, when the induced voltage (EX) is smaller than or equal to a second determination value (GB), a divided value that is obtained by dividing a motor voltage (Vm) by a motor current (Im) is set as a new motor resistance (Rm).

Abstract: An electric power steering apparatus including a motor includes: a steering torque sensor; a speed sensor; an auxiliary steering force setting unit configured to output a signal representing a linear change of a gradual increase or decrease; a map setter configured to receive a signal output from the auxiliary steering force setting unit and to set an auxiliary steering force map where a maximum steering torque, a maximum target motor current, or a ratio of a target motor current to a steering torque at a specific speed gradually increases or decreases; a current signal supply configured to output the steering torque signal and a target motor current signal corresponding to the speed signal according to the auxiliary steering force map; and a motor driving unit configured to supply a current corresponding to the target motor current signal to the motor.

Abstract: A steering control apparatus has a variable gear ratio device and a power steering device. If abnormality arises in the VGRS device, an EPS motor is controlled based on a steering wheel angle and a speed increase ratio. Thus, vehicle wheels are controlled appropriately when abnormality arises in the VGRS device. Steered angle of the vehicle wheels relative to the steering wheel angle is not changed between before and after occurrence of abnormality in the VGRS device. As a result, movement of a vehicle does not deviate from the steering wheel angle and feeling of discomfort in steering a vehicle can be reduced.

Abstract: A motor-driven power steering apparatus is provided with a sub control system including a map memory means storing a first window time setting map M1 and a second window time setting map M2 in which a window time is set shorter, a window time setting map selecting means selecting the first window time setting map M1 at a time when a torque change amount dT and a current change amount dIm are both smaller than respective predetermined change amounts, and selecting the second window time setting map M2 in the other cases, a window time deciding means collating a point coordinate of a combination of a steering torque and a motor current with the selected window time setting map so as to decide a window time, and a motor drive stop determining means determining the motor drive stop in the case that the point coordinate exists in a region corresponding to the decided window time for the window time, and when a motor drive stop determining means determines the motor drive stop, the drive of the motor controlled so

Abstract: A magnetic sensor disposed in an axial direction of a shaft of a motor detects the rotation angle of the rotor by detecting magnetism of the magnet that is disposed on one end of the shaft. A first and second conducting wires extend in parallel with an axis of the shaft, and are equidistantly positioned relative to the axis, on a virtual circle that has a center point on the axis of the shaft. The electric current flowing in the first conducting wire and the electric current flowing in the second conducting wire have the same magnitude and the same flow direction with each other at any time. When the first conducting wire and the second conducting wire are on opposite sides relative to the center point of the virtual circle, the magnetic fields around the conducting wires cancel with each other, thereby enabling accurate detection of the rotation angle.

Abstract: In a control method for an electric power steering apparatus having a steering member, a steering mechanism, and a motor for assisting steering, a steering torque applied to a steering wheel is detected, frequency analysis is performed on the detected torque, and a determination is made as to whether or not a torque component having a frequency equal to or higher than a predetermined value is included in the result of the frequency analysis. When such a torque component is included in the frequency analysis result, a predetermined rotary torque is generated in a single direction.

Abstract: There is described a method of controlling a continuously variable ratio transmission of the type comprising a continuously variable ratio unit (“variator”) which has rotary input and output members though which the variator is coupled between an engine and a driven component, the variator receiving a primary control signal and being constructed and arranged such as to exert upon its input and output members torques which, for a given variator drive ratio, correspond directly to the control signal, the method comprising: determining a target engine acceleration, determining settings of the variator's primary control signal and of an engine torque control for providing the required engine acceleration and adjusting the control signal and/or the engine torque control based on these settings, predicting a consequent engine speed change, allowing for engine and/or transmission characteristics, and correcting the settings of the control signal and engine torque based on a comparison of actual and predicted engine

Abstract: Systems and methods for determining an absolute position of a motor of an active front steering system of the vehicle are provided. In particular, the systems and methods accurately determine an absolute position of the motor upon startup of the active front steering system.

Abstract: Methods, including service methods, program products and systems are provided for sensing vehicle loads and responsively and automatically configuring a vehicle. Vehicle-mounted load sensors sense vehicle loads, a vehicle processing means calculating a load imparted to the vehicle and comparing imparted loads to load capacity ratings or thresholds and responsively adjusting a vehicle cooling, transmission, braking, suspension or engine system into a revised operating mode. Modifying a component may entail revising a load capacity rating or threshold and repeating sensing, calculating, comparing and adjusting until the revised rating or threshold is met, or progressively adjusting in proportion to a change in a historic sensed load. Adjusting of the vehicle system may be biased to a performance characteristic or a load distribution. A supervisory entity may override automatic adjustment.

Abstract: An electric power assisted steering system comprises a torque sensor, a motor connected to a part of the steering assembly to provide an assistance torque to the steering assembly and a motor controller which is adapted to receive an output signal from the torque sensor and to generate a motor torque demand signal indicative of the torque to be applied by said motor to said steering system. The motor torque demand signal comprises a driver demand component with a value dependent upon the value of said handwheel torque applied by the driver; and a diagnostic component with a value independent of said handwheel torque applied by said driver and which varies in value over time in a predetermined manner. The system further comprises a monitor that correlates the diagnostic component with the output signal and generates a signal indicating that the output signal is faulty if the correlation between the two correlated signals falls outside of a predefined range.

Abstract: A highly safe electric power steering device including a control device for determining the failure of a motor current detector based on the difference between the motor current estimate value and the detected motor current value is provided. The abnormality determining unit computes the absolute value of difference between the motor current estimate value and the detected motor current value, measures the number of times when the absolute value of difference exceeded the predetermined threshold value within the predetermined period, and measures further the cumulative value of the number of times of exceeding the threshold value within the predetermined period. When the cumulative value exceeded the predetermined reference number of times for determining abnormality, the motor current detector is determined to be abnormal.

Abstract: When an inverter or a coil set of one system fails in a motor drive apparatus having two power supply systems, a power supply relay of a failing system is turned off. In this case, while a travel speed detection value is less than a predetermined threshold value, current supply to a motor by the other system operating normally is stopped to thereby stop driving of the motor and generate no steering assist torque. Thus, a driver will be caused to surely notice occurrence of failure.