Abstract: The invention relates to a device for steering a motor vehicle, the device comprising at least one steering means to be actuated by a driver, the means being coupled electrically with at least one steerable wheel of the motor vehicle. The device further comprises a seat for the driver, the seat including a seat part which forms a seat area, and a backrest part. The steering means are coupled with the seat part and are longitudinally displaceable together with it.

Abstract: A variable end-of-travel stop mechanism, for controlling the rotation of a steering shaft in a steer-by-wire steering system having a controller, includes a first clutch assembly having a first roller clutch engaged to the steering shaft, a first rotary brake engaged to the first roller clutch, and a first electrical connector connected to the first brake and in signal communication with the controller. The first clutch assembly is operative to prevent the rotation of the steering column in a first direction when activated. The stop mechanism further includes a second clutch assembly having a second roller clutch engaged to the steering shaft, a second rotary brake engaged to the second roller clutch and a second electrical connector connected to the second brake and in signal communication with the controller. The second clutch assembly is operative to prevent the rotation of the steering column in a second direction counter to the first direction when activated.

Abstract: A steer-by-wire vehicle steering system and method of controlling such a steering system when steering into and away from a steering stop. In one embodiment, the system includes a steering reaction device (55) including a fluid displacement mechanism (71), and a valve arrangement (95) operable to vary the steering reaction provided to the vehicle operator. In another embodiment, there is a “friction” reaction device (111) including an electromagnetic coil (115) which can have a varying signal (61) applied to it to vary the steering reaction the coil imposes on a movable member (113) of the device (111). In either embodiment, the reaction device includes a spring arrangement (93;131), such that rotation of the steering wheel (51) is in opposition to a spring force.

Abstract: A steering tiller and a steered wheel(s) of a steer-by-wire steering system of a materials handling vehicle are synchronized with one another and a virtual coupling force is exerted on the steering tiller to maintain synchronization. A motor or brake is associated with the steering tiller and the positions of the tiller and the steered wheel(s) are monitored and used to control the motor or brake to apply the virtual coupling force to the tiller. Thus, an operator of the vehicle receives feedback corresponding approximately to that experienced in a mechanically coupled steering system so that synchronism is maintained between the tiller and the steered wheel(s). In this way, if the operator attempts to oversteer or outrun the steered wheel(s) by rapid rotation of the tiller, a force proportional to the operator's action is applied to oppose that action.

Abstract: A rotary actuator for a vehicle having an electric/hydraulic motor that is used to rotate a strut tube. The motor is mounted inside the suspension spring and around the tubular portion of the strut tube. A first shaft receives the output of the motor and transfers it to a gearbox that reduces the speed. A second shaft receives the output of the gearbox. A torque rod is attached to the opposite end of the second shaft and transfers the rotation of the second shaft through a semi-circular slot in the spring seat to a annular member. The annular member is further attached back to the strut tube, thus when the motor is energized, the rotation is transferred through the assembly to the strut tube causing it to rotate and steer the road wheel to which it is attached.

Abstract: A steering system is provided for a vehicle including a frame. Upper and lower control arms have first end portions that are pivotally supported on the frame at first spaced apart connections. The control arms also each include second end portions that are pivotally connected to an intermediate support member at second spaced apart connections. A steer knuckle is pivotally supported by the intermediate support member at third spaced apart connections that define a king pin axis. A drive motor is mounted on the intermediate support member and is coupled to the steering knuckle to rotate the steering knuckle about the king pin axis relative to the intermediate support member. A gear set may also be used in conjunction with the drive motor and steering knuckle. The intermediate support member is constrained against forward and aft movement, but is permitted to move upward and downward with the control arms.

Abstract: A simulated steering feel system 10 is provided including a magneto-rheological fluid rotary resistance device 12. The magneto-rheological fluid rotary resistance device 12 is utilized to impart improved feedback, torque to a steering wheel 32.

Abstract: A method and system for independently controlling the steering of at least two wheels of a vehicle includes a steering angle sensor for sensing a desired amount of turning of the vehicle and a direction for the desired amount of turning. An electronic control unit, in communication with the steering angle sensor, determines a first desired turning angle for one of the wheels and a second desired turning angle for the other one of the wheels based on the desired amount of turning of the vehicle and the direction of the turning of the vehicle. The second desired turning angle may be the same as or different from the first desired turning angle. Independent turning mechanisms are coupled to each of the wheels and receives control signals from the electronic control unit for controlling the turning angles of each of the wheels independently of the other wheel.

Abstract: A torque-based method to steer a vehicle equipped with a steer by wire system begins when a driver applies torque to a steering wheel so as to change the direction in which the vehicle travels. Two sensors, a steering wheel angle sensor and a steering wheel torque sensor then generate an angle signal and a torque signal, respectively. In the unlikely event the vehicle steering system is malfunctioning, the steering wheel torque sensor will still generate a torque signal. This torque signal is used in place of the angle signal to generate the reference signal. Once the reference signal is generated, then it can be used to generate the road wheel angle signal, which is in turn used to position the road wheels accordingly.

Abstract: A variable road feedback device (20) for a steer-by-wire system (50) comprises a housing (31) that contains a magnetorheological fluid (32), a magnetic field generator (34) for generating a variable magnetic field within the housing (31) in order to vary the viscous resistance of the magnetorheological fluid (32) therein, and a rotor (24) rotatably mounted within the housing (31) that rotates through the magnetorheological fluid (32) and is responsive to the variable viscous resistance thereof.

Abstract: A vehicle steering apparatus (10) includes a steering wheel motor (20) which is connected with a steering wheel (12) of a vehicle. The steering wheel motor (20) is energizable by electric current to resist rotation of the steering wheel (12). A variable resistor (60) is connected in parallel with the steering wheel motor (20) and is adjustable to vary the electric current which energizes the steering wheel motor. A road wheel steering motor (16) is connectable with steerable road engaging wheels of the vehicle. The road wheel steering motor (16) is energizable by electric current to effect turning movement of steerable road-engaging wheels in response to rotation of the steering wheel (12). The variable resistor (66) is connected in parallel with the road wheel steering motor (16) and is adjustable to vary electric current which energizes the road wheel steering motor.

Abstract: An automotive steer-by-wire system is disclosed that includes a first network. The first network connects a first set of controllers for controlling a first set of motors. The steer-by-wire system further includes a second network that is independent of the first network and connects a second set of controllers for controlling a second set of motors. The steer-by-wire system includes a third network that connects the first set of controllers and the second set of controllers for controlling the first or second set of motors if the first or second network is inoperative, whereby information is transmitted via the third network independent of the first network and the second network.

Abstract: The invention relates to a method for controlling the steering angle of a steered wheel of a vehicle and a system to carry out this method. A control unit (9) controls an adjustment drive (5, 7) to alter the steering angle of the steered wheel, upon an alteration to a position of a steering member (13). The extent of the alteration to the steering angle is dependent on whether an obstacle for the vehicle is detected or not by means of a distance meter (17) coupled with the control unit (9). If an obstacle is detected at high speeds, then steering angle alterations are possible which would not be permitted by the control unit at normal driving operation. Thereby, in emergency situations the driver is to be given the possibility of being able to drive past the obstacle by a steering response characteristic which is more intense.

Abstract: A vehicle chassis having substantially all of the mechanical, electrical, and structural componentry necessary for a fully functional vehicle, including at least an energy conversion system, a steering system, and a braking system. The chassis is configured for matability with a variety of different types or styles of vehicle bodies. Various prior art mechanical control linkages between a driver and controlled systems are replaced with non-mechanical control signal transmission components. Fuel cell technology is also implemented.

Abstract: A vehicle chassis having substantially all of the mechanical, electrical, and structural componentry necessary for a fully functional vehicle, including at least an energy conversion system, a steering system, and a braking system. The chassis is configured for matability with a variety of different types or styles of vehicle bodies. Various prior art mechanical control linkages between a driver and controlled systems are replaced with non-mechanical control signal transmission components. Fuel cell technology is also implemented.

Abstract: A vehicle chassis having substantially all of the mechanical, electrical, and structural componentry necessary for a fully functional vehicle, including at least an energy conversion system, a steering system, and a braking system. The chassis is configured for matability with a variety of different types or styles of vehicle bodies. Various prior art mechanical control linkages between a driver and controlled systems are replaced with non-mechanical control signal transmission components. Fuel cell technology is also implemented.

Abstract: A vehicle includes a steering system, suspension system, braking system, and energy conversion system, wherein at least one of these systems is reprogrammable such that the vehicle's ride, response, or handling is selectively variable. The systems may be programmed automatically when a body is mated to a chassis to provide the desired performance characteristics. The invention enables increased vehicle functionality for vehicle users, retailers and manufacturers.

Abstract: A vehicle chassis having substantially all of the mechanical, electrical, and structural componentry necessary for a fully functional vehicle, including at least an energy conversion system, a steering system, and a braking system. The chassis is configured for matability with a variety of different types or styles of vehicle bodies. Various prior art mechanical control linkages between a driver and controlled systems are replaced with non-mechanical control signal transmission components. Fuel cell technology is also implemented.

Abstract: A vehicle chassis having substantially all of the mechanical, electrical, and structural componentry necessary for a fully functional vehicle includes at least an energy conversion system, a steering system, and a braking system. The chassis is configured for matability with a variety of different types or styles of vehicle bodies. Various prior art mechanical control linkages between a driver and controlled systems are replaced with non-mechanical control signal transmission components. Fuel cell technology is also implemented. Further, the chassis is configured for automatic engagement of its body connection components with complementary connection components on a vehicle body when a body is sufficiently positioned against the chassis.

Abstract: A vehicle chassis having substantially all of the mechanical, electrical, and structural componentry necessary for a fully functional vehicle, including at least an energy conversion system, a steering system, and a braking system. The chassis is configured for matability with a variety of different types or styles of vehicle bodies. Various prior art mechanical control linkages between a driver and controlled systems are replaced with non-mechanical control signal transmission components. Fuel cell technology is also implemented.

Abstract: A steering apparatus for automobiles having steering operating means which is not mechanically connected to a steering mechanism, a pair of steering motors provided to different positions in the steering mechanism, and a steering control unit for distributing a necessary steering force which is obtained on the basis of a deviation between an operating position of the steering operating means and an actual operating position of the steering mechanism in a prescribed ratio so as to determine target values of the outputs of the steering motors.

Abstract: An apparatus and method for steering a vehicle (not shown) provides an input member or steering wheel for receiving steering inputs from a user; a steering-torque sensor mechanically coupled to the input member for sensing the torque applied to the steering wheel; a control circuit electronically coupled to the steering-torque sensor for producing a signal corresponding to the measured driver steering torque; an output actuator electronically coupled to the control circuit and road wheel for receiving the electronic signal and translating it into mechanical motion; and an output member or road wheel mechanically coupled to the output actuator for steering the vehicle (not shown).

Abstract: A system (10) and method for controlling a steer-by-wire steering system. The system (10) has a steering wheel control subsystem (12) that provides steering feel for the operator, a reference angle (40) to the road wheels and tracks the road wheel angle. A road wheel control subsystem (14) tracks a steering wheel angle and produces a steering wheel reference angle (32) and torque signal (34) to the steering wheel control subsystem (12). The system and method of the present invention implements the same steering requirements for a steer-by-wire steering system as a conventional steering system and can implement advanced and flexible steering functions that cannot be accomplished with a conventional steering system.

Abstract: A steering system (10) has a rack housing (12) formed of a first tube (14) and a pinion housing (16) formed of a second tube (18). A first opening (31) is provided in the first tube (14) and a second opening (33) is formed in the second tube (18). The first opening (31) and second opening (33) expose a respective fillet (32), (34). The relative position of first opening (31) and second opening (33) determine the position of the first tube (14) with respect to the second tube (18). A first bushing (40) and a second bushing (42) are used to support a rack (36) within first tube (14). A pinion shaft (60) positioned within second tube (18) has a pinion gear (62) for coupling with rack (36). Preferably a first bracket (26) and second bracket (28) are positioned on first tube (14) adjacent to first bushing (40) and second bushing (42), respectively.

Abstract: A method for implementing directional control of a motor vehicle is disclosed. In an exemplary embodiment, the method includes determining whether a failure of a primary steering system of the motor vehicle exists. If a failure of the primary steering system exists, then a yaw moment is created on the vehicle by causing a differential longitudinal force to be applied with respect to a first wheel on one side of the vehicle and a second wheel on an opposite side of the vehicle, thereby causing the vehicle to turn in a commanded direction.

Abstract: A steer-by-wire handwheel actuator in a vehicle is presented. The handwheel actuator comprises a driver input shaft; a gear train connected to the driver input shaft; a motor responsive to control signals from a controller and variably geared to the gear train; a electro-mechanical brake responsive to the control signals from the controller and geared to one of the driver input shaft and the gear train; and a stop mechanism attached to a housing and coupled to one of the electro-mechanical brake and the gear train.

Abstract: A steering device for a motor vehicle includes an actuating member for the introduction of the steering movement and a steering linkage to transfer the steering movement to the vehicle wheels. The actuating member consists of a steering wheel (1) which is rotatable about a small angle and of a measured value transmitter (2) to generate an electrical or electronic position signal. The steering linkage is actuated by an adjustment drive which is controllable by an electrical regulating device as a function of the position signal.

Abstract: The invention relates to a device for generating a steering signal for controlling an actuating drive for an adjustment of steerable wheels on motor vehicles, in particular passenger vehicles. The device comprises a non-rotatable frame having an axis of symmetry and curved guiding portions, as well as a pair of handles intended for transmitting actuating forces and being coupled with each other. The handles are mounted on the guiding portions so as to be displaceable in same direction and are able to be displaced along the guiding portions and relative to the axis of symmetry to a limited extent. The device further comprises a measurement transducer for generating one of an electrical and electronic signal for determining a position of the handles relative to the frame.

Abstract: A steering system for a vehicle, the steering system includes a rack-independent actuator. The rack-independent actuator has component parts isolates from undesirable loads by two universal joints that isolate mechanical components of the actuator from transient loads that may be encountered by the rack or rack housing.

Abstract: A steer-by-wire steering system for steering a set of road wheels is disclosed. The system comprises a controller and at least one actuator assembly connected to the controller and to the at least one wheel of the set of road wheels. The at least one actuator assembly comprises an electro-mechanical actuator connected to the controller, a crank arm connected to the electro-mechanical actuator, a steering arm connected to the at least one wheel of the set of road wheels; and a tie rod having a first end thereof connected to the crank arm and a second end thereof connected to the steering arm. The electro-mechanical actuator, in response to a signal from the controller, is operative to rotate the crank arm producing thereby a force acting through the tie rod so as to rotate the steering arm and the at least one road wheel to a desired position. The steer-by-wire steering system includes a backup system capable of assuming operative command of the steer-by-wire steering system.

Abstract: The invention concerns a steering arrangement (1) with a steering handwheel (2), which is unrotatably connected with a steering sensor, and with a wheel (3) steered by a steering drive (4) without a mechanically active connection between steering handwheel (2) and steered wheel (3). In this steering arrangement a simple way of realizing a counter action of the steered wheel on the steering handwheel (2) is wanted. For this purpose the steering sensor is made as an electrical machine (6), which works as a generator, for the production of a steering signal and is connected with a switching device (9), whose load behavior is variable.

Abstract: The invention concerns a steering arrangement (1) for a vehicle, in particular for an automotive machine, with a steering drive (4) controlled by a steering unit (8). In a steering arrangement of this kind, it is endeavoured to make the steering less straining for the operator. For this purpose the steering unit (8) has a keyboard (9) instead of a steering handwheel.

Abstract: A steer-by-wire handwheel actuator in a vehicle is presented. The handwheel actuator comprises a controller operative to accept as input thereto data from the steer-by-wire system and generate therefrom control signals; a driver input shaft; a gear train connected to the driver input shaft; a variable stop motor responsive to the control signals from the controller and variably geared to the gear train; a feedback motor responsive to the control signals from the controller and geared to one of the driver input shaft and the gear train; and a stop mechanism attached to a housing and coupled to one of the feedback motor and the gear train.

Abstract: A vehicle with a steering handle, which can be actuated by a driver of the vehicle, with at least one steerable vehicle wheel, which is actuated as a function of actuations of the steering handle, with a control system, which allows operation of the steering system on a steer-by-wire level and on a fall-back level and, at least in an emergency, switches from the steer-by-wire level to the fall-back level, with an electric and/or electronic coupling device, which couples the steering handle to the steerable vehicle wheel on the steer-by-wire level, and with a hydraulic and/or mechanical coupling device, which couples the steering handle to the steerable vehicle wheel on the fall-back level.

Abstract: A steering system for a vehicle has a steering operating device, an operating moment sensor which is assigned to the steering operating device and which senses the operating moment exercised on the steering operating device and generates a corresponding signal, and a steering angle sensor which senses a steering angle corresponding to the alignment of the steerable wheels and supplies a corresponding signal to a control unit which, in turn, determines a pertaining desired angle of the steering operating device. The control unit is constructed in order to process the signal generated by the operating moment sensor and emit an assigned desired steering moment or an assigned desired steering force. A steering device, which is mechanically uncoupled from the steering operating device, sets the desired steering moment or the desired steering force at the steerable wheels. A feedback unit is provided for setting the determined desired angle at the steering operating device.

Abstract: An overlay steering system for a vehicle includes a mechanical steering apparatus for the transfer of a steering torsionali moment at a predetermined transfer ratio to at least one steered wheel, a wheel angle sensor connected to at least one steered wheel for generating a wheel angle signal corresponding to an angle of the at least one steered wheel, a comparison device for comparing the steering angle signal and the wheel angle signal as well as for generating a comparison signal based on the steering angle and the wheel angle, and an electromechanical converter for generating the overlay torsional moment, if the comparison signal indicates the presence of a deviation from the predetermined relation between the steering angle and the wheel angle of the at least one steered wheel, resulting in a reduction of the deviation.

Abstract: A motor vehicle steering system is provided which includes: an operation member for steering a motor vehicle; a steering mechanism for turning steerable wheels of the motor vehicle; a first actuator and a second actuator each operative to apply a driving force to the steering mechanism; and a clutch mechanism operative to mechanically engage and disengage the operation member to or from the steering mechanism. When the first and second actuators operate normally, the clutch mechanism is brought into the disengaged state, and a driving force is applied to the steering mechanism from the first and second actuators and, when one of the first and second actuators malfunctions, the clutch mechanism is brought into the engaged state, and the steering assist force is generated by the other normal actuator in accordance with the operation of the operation member.

Abstract: The driver is able to predefine the desired value for the transverse dynamic behavior of the vehicle on the two or more two actuating parts. The desired value is determined as a function of the operating force applied by the driver to the actuating parts. The desired value for the transverse dynamic behavior is adjusted via actuating members. The current value for the transverse dynamic behavior which is produced by the actuating members is determined. The current value is assigned a desired deflection of the actuating parts from the rest position, and the determined desired deflection of the actuating part is adjusted on each actuating part via an actuating part control device assigned thereto.

Abstract: A steer-by-wire system of the preferred embodiment of the invention includes a steering subsystem, a turning subsystem, and a controller subsystem. The steering subsystem further includes a steering sensor to sense steering factors of a steering input, and a steering actuator to generate a steering feedback. The turning subsystem further includes a turning actuator to adjust a turning angle of a road wheel of the vehicle, and a turning sensor to sense turning factors of the turning actuator. The controller subsystem is connected to the steering sensor and to the turning sensor and controls the turning actuator and the steering actuator.

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

Abstract: A steering system comprises a steering linkage and two positioners capable of positioning the steering linkage in unison. Each positioner comprises an electronic control circuit, a servomotor and a position sensor for sensing a position of the servomotor.

Abstract: A device and method for transferring steering responsibility from a first electro-mechanical actuator to a second electro-mechanical actuator comprises a cylinder and a first piston slideably disposed within the cylinder. A second piston is slideably disposed within an interior chamber of the first piston. A first locking sleeve is disposed within the interior chamber, a second locking sleeve is disposed within the interior chamber in opposition to the first locking sleeve, a first spring is disposed within the interior chamber interposed between the first locking sleeve and the first piston, and a second spring is disposed within the interior chamber interposed between the second locking sleeve and the first piston. The pistons and the locking sleeves also each include at least one groove disposed therein. Snap rings may be disposed within the grooves. A damping mechanism may also be incorporated into the structure of the device.

Abstract: A steer by wire control system having a steering wheel unit responsive to a steering wheel torque command and a road wheel unit responsive to a road wheel unit command is disclosed. A master control unit may be employed to perform processing as necessary. A method for steering a vehicle including receiving a tie-rod force signal, a road wheel position signal, a vehicle speed signal, a steering wheel position signal, and a feedback torque signal. Combining these signals to generate the steering wheel torque command signal and road wheel command signal to provide the operator with tactile feedback, while road wheel command signals are sent to road wheel units to provide steering direction. An Ackerman correction unit may also used to correct the left and right road wheel positions to track about a common center.

Abstract: A closed loop steer by wire control system has three main components, a steering wheel unit, a roadwheel unit, and a master control unit. Signals generated by sensors in the steering wheel unit and roadwheel unit are passed back to the master control unit for processing. These signals include tie-rod force signals, and a steering wheel position signal. The master control unit uses these signals to calculate a steering wheel reaction torque signal which is sent back to the steering wheel unit to provide the operator with tactile feedback, while roadwheel command signals are sent to roadwheel units to provide steering direction. An Ackerman correction unit is also used to correct the left and right roadwheel positions to track about a common center.

Abstract: A method for actuating a “steer-by-wire” steering drive mechanism by means of at least two triggerable control motors and gear units downstream of them, by which a gear element, connected to the wheels, can be driven simultaneously, is characterized in that the two control motors can be triggered independently of one another in such a way that by them both, drive forces in both the same direction and opposite directions and of equal or different amounts oriented in both the same and in opposite directions can be generated simultaneously.

Abstract: For a wheel suspension for vehicles, in particular commercial vehicles with a wheel unit that can be rotated about an upright axis of rotation, the proposal is to design the wheel unit with its actuating and drive structure as an assembly that is situated outside the vehicle body and can be removed to the outside.

Abstract: A drag link (26) for a steer-by-wire system (10) in a motor vehicle in which the steer-by-wire system has a separate electrical actuator (20,24) for each front wheel (12,14) of the motor vehicle, the drag link comprising a first rod (30) connectable with one of the electrical actuators; a second rod (28) connectable with the other of the electrical actuators; and a locking device (32) connecting the first and second rods; wherein the first and second rods are substantially axially aligned on a common axis (A) at the locking device; wherein the locking device includes a housing member (38) having an internal surface (44) defining a bore (36) with an axis aligned with the common axis, a piston member (34) positioned in the bore in sliding engagement with the internal surface, and lock means (46) having a de-actuated state in which the piston member can move in the axial direction relative to the housing member, and an actuated state in which the piston member and the housing member are locked together; wherein

Abstract: A variable road feedback device (20) for a steer-by-wire system (50) comprises a housing (31) that contains a magnetorheological fluid (32), a magnetic field generator (34) for generating a variable magnetic field within the housing (31) in order to vary the viscous resistance of the magnetorheological fluid (32) therein, and a rotor (24) rotatably mounted within the housing (31) that rotates through the magnetorheological fluid (32) and is responsive to the variable viscous resistance thereof.

Abstract: An independent steering and/or braking control to improve motor vehicle stability and stopping utilizes a steer-by-wire system that includes a steering input system, a controller in electronic communication with the steering input system, and a plurality of roadwheel systems. Each of the roadwheel systems is in electronic communication with the controller, and each roadwheel system includes a steering actuator and a steerable wheel rotatably and operably connected to the steering actuator. The steerable wheel is configured to be angled independent of other steerable wheels and relative to a direction of travel of the motor vehicle. A method of stopping the motor vehicle as it travels includes angling a pair of the steerable wheels thereof in opposing directions.

Abstract: A hydraulic power steering system for motor vehicles which is suitable for a steer-by-wire operation, having a steering handle which can be operated by a driver. A servo motor operates steered vehicle wheels. A servo valve operates the servo motor and is constructed as a rotary slide valve arrangement having mutually rotationally movable control parts which, together, are pushed by a spring system into a normal position relative to one another. An actuator is coupled with the control parts for their rotational adjustment relative to one another and operates the servo valve. A desired steering angle value generator is operated by way of the manual steering handle. An actual steering angle value generator is operated by way of the steered vehicle wheels. An automatic control circuit operates the actuator as a function of a comparison of the desired and actual steering angles.