JP4821502B2 - Vehicle steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering gear of a vehicle of steer-by-wire system capable of steering a plurality of steering wheels independently and giving proper steering reaction force to a steering wheel in accordance with steering of the steering wheels. <P>SOLUTION: A position response control value calculating part B1 calculates a position response control value by using an average value of a value obtained by multiplying a steering angle &theta;h detected by a steering angle sensor 31 by a coefficient &alpha; of scale adjustment and steering angles &theta;wr, &theta;wl detected by right and left steering angle sensors 33R, 33L. A force response control value calculating part B2 calculates a force response control value by using resultant force obtained by adding steering force Th detected by a steering force sensor 32 to a value obtained by multiplying steering reaction force Twr, Twl detected by right and left steering reaction force sensors 34R, 34L by a coefficient &beta; of scale adjustment. Driving control parts B3, B4, B5 control position response and force response of a motor 14 for steering and right and left motors 24R, 24L for steering by using the calculated position response control value and force response control value. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a steer-by-wire vehicle steering apparatus that controls steering of steered wheels and application of a steering reaction force to a steering handle by bilateral control.

Conventionally, a steer-by-wire vehicle steering apparatus in which a steering wheel and a steered wheel are mechanically separated is well known. This steer-by-wire vehicle steering device includes, for example, a steering reaction force actuator that is connected to a steering shaft and applies a steering reaction force to a steering handle, and left and right steered wheels, as shown in Patent Document 1 below. A steering actuator that is steered by turning the steered wheel by being connected to the steered shaft to be coupled and displacing the steered shaft; Then, the steering angle of the steering wheel and the turning angle of the steered wheel are detected, and the steering actuator is driven according to the difference between the target turning angle set according to the detected steering angle and the detected turning angle. By controlling, a turning angle corresponding to the steering of the steering wheel is given to the steered wheels.
In this Patent Document 1, a plurality of electric motors are provided as steering actuators, the plurality of electric motors are regarded as one actuator and controlled, and the steered shaft is displaced in the left-right direction so that left and right steered wheels are controlled. To steer.
Also in Patent Document 2 below, a similar steer-by-wire steering control device is proposed. In this device, the steering reaction force applied to the steered shaft is detected, and the steering reaction force actuator is driven and controlled according to the detected steered reaction force. The steering reaction force is applied to the steering wheel.
JP 2004-196085 A JP 2003-137124 A

  However, since these conventional devices control the steering reaction force actuator and the steering actuator on a one-to-one basis, the left and right wheels are directly connected even when applied to a steer-by-wire steering device of a left and right independent steering system. The steering feeling like this cannot be obtained. That is, the conventional device mechanically connects the left and right wheels to both ends of the steered shaft and displaces the steered shaft by the steered actuator to simultaneously steer the left and right wheels. When a steering actuator is provided on the left and right and the left and right wheels are independently steered and applied to the left and right independent steering type, a good steering feeling cannot be obtained.

  The present invention has been made to cope with the above-described problem, and its purpose is to drive the steering reaction force actuator and the plurality of steered actuators by bilateral control that simultaneously performs position control and force control. In a state where the mechanically separated steered wheels are directly connected to each other and the steering handle and the steered wheels are connected, the steering reaction force against the steering handle and the steered wheels are controlled. An object of the present invention is to provide a vehicle steering apparatus that can apply an appropriate steering reaction force to the steering wheel as the steered wheels are steered.

  In order to achieve the above object, the present invention is characterized by a steering actuator that drives a steering handle and at least two or more turning wheels that independently steer a plurality of steered wheels that are mechanically unconnected to the steering handle. In a steer-by-wire vehicle steering apparatus including a steering actuator, steering angle acquisition means for acquiring steering angle information indicating a steering angle of a steering handle, and steered wheels that are steered independently by each of the steered actuators A steering angle acquisition unit that acquires the steering angle information that represents the steering angle, a steering force acquisition unit that acquires steering force information that represents the steering force applied to the steering handle, and each of the steering actuators. For each steered wheel steered independently, steered reaction force acquisition means for acquiring steered reaction force information representing the steered reaction force input to the steered wheel, and the steering angle information Steering angle and Based on the average value calculated by the average value calculating means, the average value calculating means for calculating the average value obtained by adjusting the scale of the turning angle for each steered wheel represented by the turning angle information, and the average value calculating means A position response control value calculating means for calculating a position response control value for the steering actuator and the turning actuator for maintaining a steering angle of the steering wheel and a turning angle of each steered wheel at a predetermined ratio; and the steering force information Calculated by the resultant force calculation means, and a resultant force calculation means for calculating a combined force by adjusting the scale of the steering reaction force represented by the steering reaction force and the turning reaction force for each steered wheel represented by the turning reaction force information. Force response control for the steering actuator and the steering actuator according to the steering force applied to the steering wheel and the steering reaction force input to each steered wheel based on the resultant force Force response control value calculation means for calculating the position, position response control value for the steering actuator calculated by the position response control value calculation means, and force response control for the steering actuator calculated by the force response control value calculation means A steering actuator drive control means for controlling the steering actuator by adding together values, a position response control value for the steering actuator calculated by the position response control value calculation means, and a force response control value calculation means There is provided a steering actuator drive control means for driving and controlling the steering actuator by adding together the calculated force response control values for the steering actuator.

According to the present invention configured as described above, the steering actuator and the turning actuator are configured based on the position response control value calculated by the position response control value calculation unit and the force response control value calculated by the force response control value calculation unit. Drive controlled.
The position response control value is calculated based on an average value obtained by adjusting the steering angle of the steering wheel and the turning angle of each turning wheel (the turning wheel independently turned by the turning actuator) after the scale adjustment. The This scale adjustment represents a ratio adjustment between the steering angle and the turning angle. Therefore, the position response control value for the steering actuator and each steered actuator is determined to be an appropriate value that correlates the steering angle and the steered angle for each steered wheel.

  For example, using the average value calculated by the average value calculation means as the target steering angle, the position response control value of the steering actuator is calculated based on the target steering angle and the steering angle acquired by the steering angle acquisition means. Further, with the average value calculated by the average value calculation means as the target turning angle, the position response control value of each turning actuator based on the target turning angle and the turning angle acquired by the turning angle acquisition means Calculate

  In addition, the force response control value is obtained by adjusting the scale of the steering force applied to the steering wheel and the turning reaction force input for each steered wheel (the steered wheel steered independently by the steered actuator). Calculated based on the combined force. This scale adjustment represents a ratio adjustment between the steering force and the turning reaction force. Therefore, the force response control value for the steering actuator and each steering actuator is determined to be an appropriate value in which the steering force and the steering reaction force for each steered wheel are associated with each other.

The steering actuator is driven and controlled by the steering actuator drive control means with a control value obtained by adding the position response control value and the force response control value calculated in this way.
Each steering actuator is also driven and controlled by the steering actuator drive control means with a control value obtained by adding the position response control value and the force response control value calculated in this way.

  By such bilateral control that simultaneously performs position response control and force response control of the steering actuator and each steering actuator, the mechanically separated steered wheels are directly connected to each other, and the steering handle and the steered wheels are connected to each other. In a state where they are connected, the steering reaction force on the steering wheel and the turning of the steered wheels are controlled. Accordingly, an appropriate steering reaction force associated with the turning of the steered wheels can be applied to the steering handle, and the driver can properly operate the steering handle while feeling the road reaction force accurately.

  Another feature of the present invention is that when the road surface state detecting means for detecting a road surface state on which the vehicle travels and the road surface state detecting means determine that the road surface state level is at a predetermined bad road level, the force response And a force response control value correcting means for reducing the force response control value calculated by the control value calculating means.

According to the present invention, when it is determined that the road surface state level is at the predetermined rough road level, the force response control value correcting means reduces the force response control value, and accordingly, the steering operation of the steering handle is heavy accordingly. Thus, vibration (rattleness) transmitted from the road surface to the steering wheel can be reduced. Therefore, the driver can perform a stable driving operation.
Note that reducing the force response control value includes a configuration in which the force response control value is zero.

  Another feature of the present invention is that the turning actuator includes a left turning actuator for turning a left turning wheel and a right turning actuator for turning a right turning wheel, and the turning reaction force acquisition means includes The left turning reaction force information representing the left turning reaction force input to the left turning wheel and the right turning reaction force information representing the right turning reaction force inputted to the right turning wheel are separately acquired. And the road surface condition detecting means includes a left turning reaction force represented by the left turning reaction force information and a right turning reaction force represented by the right turning reaction force information. The road condition level is determined based on the difference.

  According to the present invention, the left and right independent steering type steering device including the left steering actuator that steers the left steered wheel and the right steering actuator that steers the right steered wheel is configured. The road surface state level is determined from the difference between the left turning reaction force input to the steered wheel and the right turning reaction force input to the right steered wheel. For example, when the difference between the left turning reaction force and the right turning reaction force is larger than a predetermined value, it is determined that the road surface level is at a bad road level. Therefore, it is possible to easily detect a rough road.

  In other words, in the conventional steering method in which the left and right steered wheels are connected to both ends of the steered shaft as in the conventional case, when only one wheel receives a disturbance, the disturbance is transmitted to the opposite wheel and dispersed to the left and right. May not be detected accurately. On the other hand, in the present invention, since the steering reaction force information input for each of the left and right steered wheels is acquired, it is possible to detect a bad road satisfactorily even when only one wheel is on a bad road. .

  In the present invention, the steering angle acquisition means is a steering angle sensor that detects a steering angle of a steering wheel, and the turning angle acquisition means detects a turning angle of each steered wheel. The steering force acquisition means is a steering force sensor that detects a steering force applied to a steering handle, and the steering reaction force acquisition means calculates a steering reaction force input to each steered wheel. You may comprise with the steering reaction force sensor to detect.

  The steering force acquisition means is a steering force estimation means for estimating a steering force applied to a steering handle based on an operation control state of the steering actuator and an actual operation state of the steering actuator, and The turning reaction force acquisition means estimates the turning reaction force input to the steered wheels based on the operation control state of the turning actuator and the actual operation state of the turning actuator. It can also consist of force estimation means.

  For example, assuming an observer whose steering force or steering reaction force is a disturbance, the difference between the drive control torque based on the drive current for the steering actuator or the steering actuator and the actual generated torque of the steering actuator or the steering actuator, Steering torque or steering reaction force can be calculated as disturbance. If this technique for estimating the steering force and the turning reaction force is used, the steering force sensor and the turning reaction force sensor become unnecessary, and the manufacturing cost of the product can be reduced.

  Another feature of the present invention is that steering angular velocity calculation means for calculating a steering angular velocity based on the steering angle represented by the steering angle information, and a damping control value proportional to the calculated steering angular velocity are calculated. And a damping control means for adding the damping control value to the steering actuator drive control by the steering actuator drive control means.

  Further, a turning angular velocity calculating means for calculating a turning angular velocity based on the turning angle represented by the turning angle information, and calculating a damping control value proportional to the calculated turning angular velocity, Damping control means for adding a control value to drive control of the turning actuator by the turning actuator drive control means may be provided.

  According to the present invention, speed damping control is added to the steering actuator or the steering actuator, and the response characteristic of force control can be improved. In other words, the response control characteristics related to the force can be stabilized, the gain of the force response control for the steering actuator and the steering actuator can be set large, and the steering operation feeling of the steering wheel by the driver can be further increased. Become good.

Another feature of the present invention is that, in the average value calculation means, a scale adjustment ratio between a steering angle represented by the steering angle information and a turning angle for each steered wheel represented by the turning angle information. Is provided with a first changing means for changing according to the traveling state of the vehicle.
In this case, the traveling state of the vehicle is, for example, the traveling speed of the vehicle, the turning radius of the vehicle, or both. When the traveling state of the vehicle is the traveling speed, a vehicle speed sensor that detects the vehicle speed may be newly provided to use the vehicle speed detected by the vehicle speed sensor. When the running state of the vehicle is a turning radius, the steering angle detected by the steering angle sensor may be used. According to this, the relationship between the steering angle by the steering operation of the steering wheel and the turning angle at which the steered wheels are steered can be changed according to the running state of the vehicle, and the steering characteristics of the vehicle can be changed to the running state of the vehicle. Can be changed according to

Furthermore, another feature of the present invention is that the resultant force calculation means adjusts the scale between the steering force represented by the steering force information and the turning reaction force for each steered wheel represented by the turning reaction force information. There is provided a second changing means for changing the ratio according to the traveling state of the vehicle.
In this case as well, as the running state of the vehicle, the running speed of the vehicle detected by the vehicle speed sensor, the turning radius detected by the steering angle sensor, or both can be used. According to this, the steering reaction force to the steering wheel can be changed according to the traveling state of the vehicle, and the steering reaction force characteristic of the vehicle can be changed according to the traveling state of the vehicle.

<First Embodiment>
Hereinafter, a vehicle steering apparatus according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 schematically shows a steering apparatus for a vehicle according to the embodiment.

  This vehicle steering apparatus mechanically includes a steering operation apparatus 10 that is steered by a driver, and a steering apparatus 20 that steers left and right front wheels FWL and FWR as steered wheels according to the steering operation of the driver. A separate steer-by-wire system is used. The steering operation device 10 includes a steering handle 11 as an operation unit that is rotated by a driver. The steering handle 11 is fixed to the upper end of the steering shaft 12, and the output shaft of a steering electric motor 14 as a steering actuator is connected to the lower end of the steering shaft 12 via a speed reduction mechanism 13. The steering electric motor 14 (hereinafter simply referred to as the steering motor 14) gives a reaction torque to the steering operation of the steering handle 11 by the driver, and the rotational force is steered via the speed reduction mechanism 13. It is transmitted to the shaft 12. However, in the steering motor 14, the direction in which the steering handle 11 is rotated in the right direction is positive rotation, and the direction in which the steering handle 11 is rotated in the left direction is negative rotation. The steering motor 14 rotates positively with a positive control value and rotates negatively with a negative control value.

A steering angle sensor 31 and a steering force sensor 32 are assembled to the steering shaft 12. The steering angle sensor 31 detects the rotation angle of the steering handle 11 from the reference position and outputs it as the steering angle θh. In this case, for the steering angle θh, the reference position is “0”, the right rotation angle of the steering handle 11 is represented by a positive value, and the left rotation angle is represented by a negative value.
As the steering angle sensor 31, a rotation angle sensor provided in the steering motor 14 may be used.

  The steering force sensor 32 detects a torque acting on the steering shaft 12 and outputs it as a steering force Th. The steering force Th represents the steering force when the steering handle 11 is steered in the right direction as positive, and represents the steering force when the steering handle 11 is steered in the left direction as negative. Therefore, the direction represented by the sign of the steering angle θh and the steering force Th is the same as the direction of rotation represented by the sign of the steering motor 14.

The steering device 20 is a left and right independent steering system that independently steers the left and right front wheels FWL and FWR as steered wheels, and the left steering unit 20L that steers the left front wheel FWL and the right front wheel FWR. A right steering section 20R for steering.
The steered portions 20L and 20R include steered shafts 21L and 21R that extend in the left-right direction of the vehicle. One end of the steered shafts 21L and 21R is connected to the left and right front wheels FWL and FWR via a tie rod 22L and 22R and a knuckle arm 23L and 23R, respectively, such that the steerable shaft can be steered.

The left and right front wheels FWL and FWR are steered left and right by the axial displacement of the steered shafts 21L and 21R, respectively. The steered shafts 21L and 21R are respectively assembled with steered electric motors 24L and 24R serving as steered actuators and ball screw mechanisms 25L and 25R constituting a speed reduction mechanism. Each of the steering electric motors 24L and 24R rotates the left and right front wheels FWL and FWR by rotation, respectively, and the rotation is decelerated by the ball screw mechanisms 25L and 25R and converted into a linear motion, thereby turning the steering shaft 21L. , 21R.
In the steering electric motors 24L and 24R, the direction in which the left and right front wheels FWL and FWR are steered in the right direction is positive rotation, and the direction in which the left and right front wheels FWL and FWR are steered in the left direction is negative rotation. The steering electric motors 24L and 24R also rotate positively with a positive control value and negatively rotate with a negative control value.
Hereinafter, the steered electric motor 24L is referred to as a left steered motor 24L, and the steered electric motor 24R is referred to as a right steered motor 24R.

Steering angle sensors 33L and 33R and steered reaction force sensors 34L and 34R are assembled to the steered shafts 21L and 21R, respectively. Each turning angle sensor 33L, 33R detects the amount of axial displacement from the reference position of the turning shaft 21L, 21R, and outputs it as the turning angle θwl, θwr of the left and right front wheels FWL, FWR. In this case, the turning angles θwl and θwr are set to the reference position “0”, the rightward turning angles of the left and right front wheels FWL and FWR are expressed as positive values, and the leftward turning angles of the left and right front wheels FWL and FWR are represented. Is expressed as a negative value.
In addition, you may make it utilize the rotation angle sensor provided in the motors 24L and 24R for steering as the steering angle sensors 33L and 33R.
Hereinafter, the turning angle sensor 33L is referred to as a left turning angle sensor 33L, and the turning angle sensor 33R is referred to as a right turning angle sensor 33R. Further, the turning angle detected by the turning angle sensor 33L is referred to as a left turning angle θwl, and the turning angle detected by the right turning angle sensor 33R is referred to as a right turning angle θwr.

The steered reaction force sensors 34L and 34R detect the force input from the road surface to the steered shafts 21L and 21R via the left and right front wheels FWL and FWR based on the distortion of the steered shafts 21L and 21R, respectively. Output as reaction forces Twl and Twr. In this case, the steering reaction forces Twl and Twr represent the steering reaction force in the right direction of the left and right front wheels FWL and FWR as positive, and represent the steering reaction force in the left direction of the left and right front wheels FWL and FWR as negative. Therefore, the direction represented by the positive and negative of the turning angles θwl and θwr and the steering reaction forces Twl and Twr is the same as the rotational direction represented by the positive and negative of the steering motors 24L and 24R.
The turning reaction forces Twl and Twr may be calculated based on the torque acting in the turning motors 24L and 24R or the ball screw mechanisms 25L and 25R.
Hereinafter, the turning reaction force sensor 34L is referred to as a left turning reaction force sensor 34L, and the turning reaction force sensor 34R is referred to as a right turning reaction force sensor 34R. Further, the turning reaction force detected by the left turning reaction force sensor 34L is referred to as a left turning reaction force Twl, and the turning reaction force detected by the right turning reaction force sensor 34R is referred to as a right turning reaction force Twr. Call.

Next, the electric control device 40 that controls the rotation of the steering motor 14, the left steering motor 24L, and the right steering motor 24R will be described.
The electric control device 40 includes an electronic control unit (hereinafter referred to as ECU) 41, a drive circuit 42 that drives the steering motor 14, a drive circuit 43L that drives the left steering motor 24L, and a right steering motor. And a drive circuit 43R for driving 24R.

  The ECU 41 includes a microcomputer including a CPU, a ROM, a RAM, and the like as main parts, and includes a steering force sensor 32, a steering angle sensor 31, a left turning angle sensor 33L, a right turning angle sensor 33R, and a left turning reaction force sensor. 34L and a right turning reaction force sensor 34R are connected to detect a steering angle θh, a steering force Th, a left turning angle θwl, a right turning angle θwr, a left turning reaction force Twl, and a right turning reaction force Twr. . The ECU 41 executes a control program based on each sensor detection value to calculate a motor control amount, and the steering motor 14, the left turning motor 24L, and the right turning through the drive circuits 42, 43L, and 43R. The drive motor 24R is driven and controlled.

Next, the operation of the embodiment configured as described above will be described with reference to the functional block diagram of FIG. This functional block diagram and the subsequent functional block diagrams represent the functions of the ECU 41 realized by executing the program in block diagrams.
The ECU 41 includes a position response control value calculation unit B1 as a position response control value calculation unit, a force response control value calculation unit B2 as a force response control value calculation unit, a drive control unit B3 as a steering actuator drive control unit, Drive control parts B4 and B5 are provided as steering actuator drive control means.

The position response control value calculation unit B1 includes scale adjustment units 101 and 111, an addition unit 102, an average value calculation unit 103, and a differentiation calculation unit 104.
The scale adjustment unit 101 multiplies the left turning angle θwl detected by the left turning angle sensor 33L by the scale adjustment coefficient α and outputs the result. Similarly, the scale adjustment unit 111 multiplies the right turning angle θwr detected by the right turning angle sensor 33R by the scale adjustment coefficient α and outputs the result. This scale adjustment coefficient α determines the ratio (scaling) between the steering angle and the turning angle that is the object of control, and the steering angle of the steering handle 11 with respect to the turning angle of the left and right front wheels FWL and FWR in the conventional vehicle. Taking into account the ratio (steering gear ratio), the steering characteristics of the vehicle (specifically, the characteristics of the turning angles of the left and right front wheels FWL and FWR with respect to the steering angle by the turning operation of the steering handle 11) are obtained as desired characteristics. It is a constant determined in advance to be set.

The adding unit 102 includes the steering angle θh detected by the steering angle sensor 31, the adjusted left turning angle α · θwl adjusted by the scale adjusting unit 101, and the adjusted right turning angle α adjusted by the scale adjusting unit 111. • Addition operation is performed with θwr. The added value (θh + α · θwl + α · θwr) is output to an average value calculation unit 103 as an average value calculation means.
The average value calculation unit 103 calculates the average value ((θh + α · θwl + α · θwr) / 3) of the steering angle θh and the adjusted left turning angle α · θwl and the adjusted right turning angle α · θwr. To do. The calculated average value is the proportional term control command value θ * in the position response control of the steering motor 14, the left turning motor 24L, and the right turning motor 24R.
Further, the differential operation unit 104 performs differential operation on the average value calculated by the average value calculation unit 103. This differentially calculated value becomes the differential term control command value dθ * / dt in the position response control of the steering motor 14, the left steering motor 24L, and the right steering motor 24R.
In the drawings, “s” indicates a Laplace operator.

The position response control value calculation unit B1 calculates a control value by PD (proportional differentiation) control for controlling the position of the steering handle 11 by the steering motor 14, in order to calculate a differential calculation unit 112, subtraction units 113, 114, Gain multiplying sections 115 and 116, an adding section 117, a scale adjusting section 118, and an inertia multiplying section 119 are provided.
The subtraction unit 113 inputs the proportional term control command value θ * calculated by the average value calculation unit 103 and also inputs the steering angle θh detected by the steering angle sensor 31 as a feedback value. The steering angle θh is subtracted from θ * and output to the gain multiplier 115. The gain multiplication unit 115 multiplies the subtraction result (θ * −θh) by a predetermined proportional term gain Kph, and outputs the multiplication result Kph · (θ * −θh) as a proportional term control value.

  The differential calculation unit 112 calculates a steering angular velocity dθh / dt by performing a differential calculation on the steering angle θh detected by the steering angle sensor 31 and outputs the calculated steering angular velocity dθh / dt to the subtraction unit 114. The subtraction unit 114 inputs the differential term control command value dθ * / dt calculated by the differential calculation unit 104 and also inputs the steering angular velocity dθh / dt from the differential calculation unit 112 as a feedback value. The steering angular velocity dθh / dt is subtracted from the value dθ * / dt and output to the gain multiplier 116. The gain multiplication unit 116 multiplies the subtraction result (dθ * / dt−dθh / dt) by a predetermined differential term gain Kvh, and performs differential term control on the multiplication result Kvh · (dθ * / dt−dθh / dt). Output as a value.

The proportional term control value Kph · (θ * −θh) calculated by the gain multiplier 115 and the differential term control value Kvh · (dθ * / dt−dθh / dt) calculated by the gain multiplier 116 are added. The value is input to the unit 117 and added, and the added value is output to the scale adjustment unit 118. The scale adjustment unit 118 multiplies the output value of the addition unit 117 by a predetermined scale adjustment coefficient β.
The scale adjustment coefficient β determines the ratio (scaling) between the steering force Th and the steering reaction forces Twl and Twr, which are the objects to be controlled, and the vehicle steering characteristics (specifically, the left and right front wheels FWL and FWR) It is a constant determined in advance so as to set a desired characteristic of the turning operation characteristic of the steering handle 11 with respect to the turning reaction forces Twl and Twr inputted.
The calculated value scale-adjusted by the scale adjustment unit 118 is output to the inertia multiplication unit 119. The inertia multiplication unit 119 multiplies the output value from the scale adjustment unit 118 by a constant Jh proportional to the inertia of the steering motor 14 and outputs the result to the calculation unit 150.

Further, the position response control value calculation unit B1 calculates a control value by PD (proportional differentiation) control for controlling the position of the left front wheel FWL by the left steering motor 24L. 123, 124, gain multipliers 125, 126, an adder 127, and an inertia multiplier 129.
The subtraction unit 123 inputs the proportional term control command value θ * calculated by the average value calculation unit 103 and also inputs the multiplication value α · θwl from the scale adjustment unit 101 as a feedback value. The adjusted left turning angle α · θwl is subtracted from θ * and output to the gain multiplier 125. The gain multiplication unit 125 multiplies the subtraction result (θ * −α · θwl) by a predetermined proportional term gain Kpw, and adds the multiplication result Kpw · (θ * −α · θwl) as a proportional term control value. To 127.

  Further, the differential operation unit 122 performs differential operation on the multiplication value α · θwl from the scale adjustment unit 101 to calculate the adjusted left-turn angular velocity d (α · θwl) / dt and outputs it to the subtraction unit 124. The subtraction unit 124 inputs the differential term control command value dθ * / dt calculated by the differentiation calculation unit 104 and feeds back the adjusted left-turning angular velocity d (α · θwl) / dt output from the differentiation calculation unit 122. The value is input as a value, and the adjusted left-turning angular velocity d (α · θwl) / dt is subtracted from the differential term control command value dθ * / dt and output to the gain multiplier 126. The gain multiplication unit 126 multiplies the subtraction result (dθ * / dt−d (α · θwl) / dt) by a predetermined differential term gain Kvw, and the multiplication result Kvw · (dθ * / dt−d (α .Theta.wl) / dt) is output to the adding unit 127 as a differential term control value.

  The adder 127 includes the proportional term Kpw · (θ * −α · θwl) calculated by the gain multiplier 125 and the differential term Kvw · (dθ * / dt−d (α · θwl) calculated by the gain multiplier 126. ) / Dt) is added and output to the inertia multiplier 129. The inertia multiplication unit 129 multiplies the output value from the addition unit 127 by a constant Jw proportional to the inertia of the left-turning motor 24L, and outputs the result to the calculation unit 160.

Further, the position response control value calculation unit B1 calculates the control value by the PD (proportional differentiation) control for controlling the position of the right front wheel FWR by the right steering motor 24R. 133, 134, gain multipliers 135, 136, an adder 137, and an inertia multiplier 139.
The subtraction unit 133 inputs the proportional term control command value θ * calculated by the average value calculation unit 103 and also inputs the multiplication value α · θwr from the scale adjustment unit 111 as a feedback value. The adjusted right turning angle α · θwr is subtracted from θ * and output to the gain multiplier 135. The gain multiplication unit 135 multiplies the subtraction result (θ * −α · θwr) by a predetermined proportional term gain Kpw, and adds the multiplication result Kpw · (θ * −α · θwr) as a proportional term control value. To 137.

  Further, the differential calculation unit 132 calculates the adjusted right-turning angular velocity d (α · θwr) / dt by performing a differential calculation on the multiplication value α · θwr from the scale adjustment unit 111 and outputs the calculated value to the subtraction unit 134. The subtraction unit 134 inputs the differential term control command value dθ * / dt calculated by the differentiation calculation unit 104 and feeds back the adjusted right turning angular velocity d (α · θwr) / dt output from the differentiation calculation unit 132. The value is input as a value, and the adjusted right-turning angular velocity d (α · θwr) / dt is subtracted from the differential term control command value dθ * / dt and output to the gain multiplier 136. The gain multiplication unit 136 multiplies the subtraction result (dθ * / dt−d (α · θwr) / dt) by a predetermined differential term gain Kvw, and multiplies the result Kvw · (dθ * / dt−d (α Θwr) / dt) is output to the adder 137 as a derivative term control value.

  The adder 137 includes the proportional term Kpw · (θ * −α · θwr) calculated by the gain multiplier 135 and the differential term Kvw · (dθ * / dt−d (α · θwr) calculated by the gain multiplier 136. ) / Dt) and outputs the result to the inertia multiplier 139. The inertia multiplication unit 139 multiplies the output value from the addition unit 137 by a constant Jw proportional to the inertia of the right steering motor 24R, and outputs the result to the calculation unit 170.

The force response control value calculation unit B2 applies the steering force Th applied to the steering handle 11, the left turning reaction force Twl input to the left front wheel FWL, and the right turning reaction force Twr input to the right front wheel FWR. The control values for the steering motor 14, the left steering motor 24L, and the right steering motor 24R for force response control are calculated.
The force response control value calculation unit B2 includes scale adjustment units 141, 142, and 145, a calculation unit 143, and a gain multiplication unit 144.

The scale adjustment unit 141 multiplies the left turning reaction force Twl detected by the left turning reaction force sensor 34L by the scale adjustment coefficient β described above and outputs the result to the calculation unit 143.
The scale adjustment unit 142 multiplies the right turning reaction force Twr detected by the right turning reaction force sensor 34R by the scale adjustment coefficient β described above and outputs the result to the calculation unit 143.
The calculation unit 143 adds the steering force Th detected by the steering force sensor 32, the adjustment value β · Twl output from the scale adjustment unit 141, and the adjustment value β · Twr output from the scale adjustment unit 142. The resultant resultant force is output to the gain multiplier 144 and corresponds to the resultant force calculation means of the present invention. The output value (Th + β · Twl + β · Twr) of the calculation unit 143 follows the steering motor Th, the left steering motor 24L, and the right steering motor 24R to the steering force Th and the left and right steering reaction forces Twl and Twr. It represents the control value for driving.

The gain multiplication unit 144 multiplies the output value (Th + β · Twl + β · Twr) of the calculation unit 143 by the proportional term gain Ktp for force response control, and calculates the output value Ktp · (Th + β · Twl + β · Twr). In addition to outputting to 160 and 170, it also outputs to the calculation unit 150 via the scale adjustment unit 145.
The scale adjustment unit 145 multiplies the aforementioned scale adjustment coefficient α by the output value Ktp · (Th + β · Twl + β · Twr) from the gain multiplication unit 144.

  The calculation unit 150 constitutes a part of the drive control unit B3 for the steering motor 14, and adds the output values of the inertia multiplication unit 119 and the scale adjustment unit 145 to the current command value calculation unit 151. Output. The current command value calculation unit 151 calculates the current command value Ich by dividing the output value from the calculation unit 150 by the torque constant Kth related to the steering motor 14 and outputs the current command value Ich to the drive circuit 42. The drive circuit 42 controls the rotation of the steering motor 14 in accordance with the current command value Ich.

  The calculation unit 160 constitutes a part of the drive control unit B4 for the left steering motor 24L, and adds the output values of the inertia multiplication unit 129 and the gain multiplication unit 144 to add the current command value calculation unit 161. Output to. The current command value calculation unit 161 calculates the current command value Icl by dividing the output value from the calculation unit 160 by the torque constant Ktw related to the left steering motor 24L, and outputs it to the drive circuit 43L. The drive circuit 43L controls the rotation of the steering motor 24L according to the current command value Icl.

  Similarly, the calculation unit 170 constitutes a part of the drive control unit B5 for the right-turning motor 24R, and adds the output values of the inertia multiplication unit 139 and the gain multiplication unit 144 to add a current command value. The result is output to the calculation unit 171. The current command value calculation unit 171 calculates the current command value Icr by dividing the output value from the calculation unit 170 by the torque constant Ktw related to the right steering motor 24R, and outputs it to the drive circuit 43R. The drive circuit 43R controls the rotation of the steering motor 24R according to the current command value Icr.

By such control of the position response control value calculation unit B1, force response control value calculation unit B2 and drive control units B3, B4, and B5 of the ECU 41, the steering motor 14, the left steering motor 24L, and the right steering motor 24R position response control and force response control are performed simultaneously.
Specifically, the steering reaction force input to the left and right front wheels FWL and FWR from the road surface is changed by operating the steering handle 11, and the scaled steering angle, right turning angle, and left turning angle are adjusted. Are deviated from their average values, the steering motor 14, the left turning motor 24L, and the right turning motor 24R are controlled by the position response control value calculation unit B1 and the drive control units B3, B4, and B5. Drive control is performed so that a predetermined relationship (θh = α · θwl = α · θwr = (θh + α · θwl + α · θwr) / 3) is established.

In addition, even when the scale-adjusted steering angular velocity, left-turning angular velocity, and right-turning angular velocity deviate from their average values, they become average values (dθh / dt = d (α · θwl) / dt = d (α · θwr) / dt = d ((θh + α · θwl + α · θwr) / 3) / dt), the steering motor is controlled by the position response control value calculation unit B1 and the drive control units B3, B4, and B5. 14. The left steering motor 24L and the right steering motor 24R are driven and controlled.
As a result, the steering wheel 11, the left front wheel FWL, and the right front wheel FWR are subjected to position response control so that the predetermined relationship is always established.

Further, when the steering force Th for the steering handle 11 or the turning reaction forces Twl and Twr input to the left and right front wheels FWL and FWR from the road surface are generated, the force response control value calculation unit B2 and the drive control units B3 and B4 , B5, the steering motor 14, the left steering motor 24L, and the right steering motor 24R are driven and controlled based on the resultant force (Th + β · Twl + β · Twr) obtained by adjusting the scales of these forces. As a result, the steering motor 14, the left steering motor 24L, and the right steering motor 24R are driven and controlled to follow the steering force Th and the steering reaction forces Twl and Twr, and are accurately subjected to force response control.
When this force response control is added to the position response control, the steering wheel of the driver is lightened and a soft steering feeling is obtained.

  As can be understood from the above operation description, according to the first embodiment, the position response control and force response control of the steering motor 14, the position response control and force response control of the left steering motor 24L, and the right By bilateral control in which position response control and force response control of the steering motor 24R are mutually related and performed at the same time, the left and right front wheels FWL and FWR which are mechanically separated are directly connected, and the steering handle 11 and each In a state where the front wheels FWL and FWR are connected, the steering reaction force on the steering handle 11 and the steering of the left and right front wheels FWL and FWR are controlled. Accordingly, an appropriate steering reaction force associated with the turning of the front wheels FWL and FWR that are the steered wheels can be applied to the steering handle 11, and the driver can appropriately steer the steering handle 11 while feeling the road reaction force accurately. become able to.

<First Modification of First Embodiment>
Next, a first modification of the first embodiment will be described. As shown in FIG. 3, the vehicle steering apparatus according to the first modification is obtained by adding a force response reduction coefficient multiplier 146 that reduces the force response control value when traveling on a rough road.
The force response reduction coefficient multiplier 146 is provided on the output side of the gain multiplier 144, and multiplies the output value (Ktp · (Th + β · Twl + β · Twr)) of the gain multiplier 144 by the reduction coefficient Kx. The result (Kx · Ktp · (Th + β · Twl + β · Twr)) is output to the scale adjustment unit 145 and the calculation units 160 and 170.

The reduction coefficient Kx multiplied by the force response reduction coefficient multiplication unit 146 is set to a reduction coefficient of less than 1 when the road on which the vehicle is traveling is a bad road. That is, when traveling on a rough road, the force response control value is reduced.
Hereinafter, the setting process of the reduction coefficient Kx performed by the force response reduction coefficient multiplication unit 146 will be described with reference to FIG.
FIG. 4 is a flowchart showing a reduction coefficient setting routine performed by the force response reduction coefficient multiplication unit 146 as a function unit in the ECU 41. This process is stored as a control program in the ROM of the ECU 41, and is repeatedly executed at a predetermined cycle synchronized with each control function unit while the ignition switch is on.

  When this reduction coefficient setting routine is activated, the force response reduction coefficient multiplying unit 146 applies the left turning reaction force Twl detected by the left turning reaction force sensor 34L and the right turning reaction force sensor 34R in step S11. The right turning reaction force Twr detected in this way is input. Subsequently, in step S12, an absolute value | Twl−Twr | (hereinafter referred to as reaction force difference ΔT) of a difference between the left turning reaction force Twl and the right turning reaction force Twr is calculated. This reaction force difference ΔT represents the road surface state level of the road on which the vehicle is traveling, and it can be said that the larger the value, the worse the road surface state level.

Next, in step S13, the force response reduction coefficient multiplication unit 146 calculates an average value ΔTav of the reaction force difference ΔT in the most recent predetermined period. Subsequently, in step S14, it is determined whether or not the average value ΔTav is larger than a preset reference value ΔT0. This reference value ΔT0 is a determination reference value for determining whether or not the road surface condition is a bad road.
Therefore, the processing of steps S11 to S14 corresponds to the road surface state detecting means in the present invention.

If it is determined in step S14 that ΔTav ≦ ΔT0 (S14: NO), the road surface condition is good. In this case, the process proceeds to step S15, and it is determined whether or not the flag F is set to “1”. The flag F is set to “0” when the routine is started, and is set to F = 1 when the reduction coefficient Kx is adjusted to be reduced (Kx <1).
Since F = 0 when this setting routine is started, in this case, the reduction coefficient Kx is set to “1” (Kx = 1) in step S16, and this routine is once ended.
This routine is repeated at a predetermined short cycle. When the vehicle enters a rough road and the reaction force difference average value ΔTav exceeds the reference value ΔT0 (S14: YES), the force response reduction coefficient multiplication unit 146 advances the process to step S17.

In step S17, a reduction coefficient Kx is calculated based on the reduction coefficient table shown in FIG. This reduction coefficient table associates the continuous time determined to be “YES” in step S14, that is, the continuous time determined to be rough road traveling, and the reduction coefficient Kx, and is stored in the ROM of the ECU 41. . As shown in the reduction coefficient table, the reduction coefficient Kx is gradually reduced in accordance with the elapsed time since it was determined that the vehicle traveled on a rough road in step S14. Since this setting routine is repeatedly executed at a predetermined cycle, Kx = 1 is set at the time when it is determined that the vehicle is traveling on a rough road, and is reduced as time passes.
In the present embodiment, when the reduction coefficient Kx is reduced to the minimum value Kmin, the value is retained, but may be reduced to the value “0” as it is.

When the reduction coefficient Kx is set in step S17, it is subsequently checked in step S18 whether or not the flag F is set to “0”. If F = 0 (S18: YES), F in step S19. = 1 and exit this routine.
When this routine is repeated in this way, the force response control value is gradually reduced during rough road traveling. In this case, the steering operation of the steering handle 11 becomes gradually heavier, and vibrations (rattleness) transmitted from the road surface to the steering handle 11 can be reduced. Therefore, the driver can perform a stable driving operation. Further, since the reduction of the force response control value is gradually performed over time, the driver does not feel uncomfortable.

When the vehicle enters the flat road from such a state, the determination in step S14 is “NO”, and the process proceeds to step S15. In step S15, it is determined whether or not the flag F is set to “1”. In this case, since F = 1, the process proceeds to step S20.
In step S20, the reduction coefficient Kx is calculated based on the return reduction coefficient table shown in FIG. This return reduction coefficient table associates the continuous time determined as “YES” in step S14, that is, the elapsed time after moving from a rough road to a flat road, and the reduction coefficient Kx in the ROM of the ECU 41. Remembered.

  The process of step S20 is to gradually return the reduction coefficient Kx to the value “1”. The initial value of the reduction coefficient Kx initially set in step S20 is set to the immediately preceding control cycle. The reduction coefficient Kx that has been used is obtained. Therefore, if the rough road determination period is short and the reduction coefficient Kx has not reached the minimum value Kmin, the initial value of the reduction coefficient Kx is not the initial value Kmin shown in the return reduction coefficient table. The minimum value (> Kmin) at that time is set.

Subsequently, in step S21, it is determined whether or not the reduction coefficient Kx has increased to a value “1”. If Kx <1, this routine is temporarily exited. Thus, the reduction coefficient Kx increases as time elapses by repeating this routine. When it is determined in step S21 that the increase recovery of the reduction coefficient Kx has been completed (Kx = 1), the flag F is reset to the value “0” in step S22, and this routine is exited.
The processes in steps S17 and S20 correspond to the force response control value correcting means of the present invention.

Thus, after the vehicle enters the flat road, the force response control value is gradually increased and restored, and the steering operation of the steering handle 11 is gradually lightened. In addition, since the increase return of the force response control value is gradually performed over time, the driver does not feel uncomfortable.
As a result, an appropriate steering reaction force according to the road surface condition is obtained for the driver.

<Second Modification of First Embodiment>
Next, a second modification of the first embodiment will be described. As shown in the functional block diagram of FIG. 7, the vehicle steering apparatus according to the second modified example includes the damping control units B6H, B6L, and B6R in the functional block of FIG. 3 according to the first modified example of the first embodiment. It is added to the figure. These damping control units B6H, B6L, and B6R include damping coefficient multiplying units 152, 162, and 172 for damping control of the steering motor 14, the left steering motor 24L, and the right steering motor 24R, respectively. .

  The damping control unit B6H includes a damping coefficient multiplication unit 152. The damping coefficient multiplier 152 receives the steering angular velocity dθh / dt from the differential calculator 112, multiplies the steering angular velocity dθh / dt by the damping coefficient Ktvh, and outputs the result to the calculator 150. In the calculation unit 150, the value Ktvh · dθh / dt obtained by multiplying the steering angular velocity dθh / dt by the damping coefficient Ktvh is subtracted from the addition value of the control value from the inertia multiplication unit 119 and the control value from the scale adjustment unit 145. Is done. As a result, the steering motor 14 is subjected to damping control.

  The damping control unit B6L includes a damping coefficient multiplication unit 162. The damping coefficient multiplying unit 162 inputs the adjusted left turning angular velocity d (α · θwl) / dt from the differential calculation unit 122, and multiplies the adjusted left turning angular velocity d (α · θwl) / dt by the damping coefficient Ktvw. To the arithmetic unit 160. In the calculation unit 160, the damping coefficient Ktvw is set to the adjusted left-turning angular velocity d (α · θwl) / dt from the addition value of the control value from the inertia multiplication unit 129 and the control value from the force response reduction coefficient multiplication unit 146 Is multiplied by Ktvw · d (α · θwl) / dt. As a result, the left steering motor 24L is subjected to damping control.

  Similarly, the damping control unit B6R includes a damping coefficient multiplication unit 172. The damping coefficient multiplying unit 172 receives the adjusted right turning angular velocity d (α · θwr) / dt from the differentiation calculating unit 132, and multiplies the adjusted right turning angular velocity d (α · θwr) / dt by the damping coefficient Ktvw. To the arithmetic unit 170. In the calculation unit 170, the damping coefficient Ktvw is set to the adjusted right turning angular velocity d (α · θwr) / dt from the addition value of the control value from the inertia multiplication unit 139 and the control value from the force response reduction coefficient multiplication unit 146. Is multiplied by Ktvw · d (α · θwr) / dt. As a result, the right steering motor 24R is subjected to damping control.

Thereby, speed damping control is further added to the steering motor 14, the left steering motor 24L, and the right steering motor 24R in addition to the control of the first embodiment, and the force response control value calculation unit B2 The response characteristic of force control can be improved. Therefore, the force response control characteristic can be stabilized, and the proportional term gain Ktp by the gain multiplier 144 related to the control of the driving force by the steering motor 14, the left steering motor 24L, and the right steering motor 24R can be obtained. It becomes possible to set a larger value, and the feeling of steering operation of the steering wheel 11 by the driver becomes better.
Such damping control units B6H, B6L, and B6R may be combined with the first embodiment shown in FIG.

Second Embodiment
Next, the steering force sensor 32 and the left and right turning reaction force sensors 34L and 34R of the first embodiment are omitted, and the steering force Th and the left and right turning reaction forces Twl and Twr are changed to the steering angle θh and the left and right turning forces. A second embodiment of the present invention that is estimated using the steering angles θwl and θwr will be described. In the second embodiment, as shown in FIG. 8, a steering force estimation unit B7H is provided instead of the steering force sensor 32 of the first embodiment, and a left turning reaction force is substituted for the left turning reaction force sensor 34L. An estimation unit B7L is provided, and a right turning reaction force estimation unit B7R is provided instead of the right turning reaction force sensor 34R. Other parts are the same as those in the first embodiment except for the calculation unit 143 ′. Only the parts different from the first embodiment will be described below.
In the example shown in FIG. 8, a steering force estimation unit B7H, a left turning reaction force estimation unit B7L, and a right turning reaction force estimation unit B7R are provided in the first modification of the first embodiment. The present invention may be applied to the first embodiment or its second modification.

  The estimation of the steering force Th and the left and right steering reaction forces Twl and Twr follows the theory of disturbance observers. Before describing these estimation units B7H, B7L, and B7R, the disturbance observers will be briefly described. deep. A block diagram of the disturbance observer relating to the steering motor 14 is shown in FIG. The steering motor 14 is rotated by being driven by the drive current Ich, and a disturbance torque (in this case, the disturbance torque is a steering force) acts in a direction to prevent the rotation drive by the drive current Ich. That is, the steering motor 14 is actually rotated by a torque obtained by subtracting the disturbance torque (steering force) from the driving torque generated by the driving current Ich.

  In the drawing, the operation state of the steering motor 14 is represented by a functional block diagram. In other words, the current command value Ich is multiplied by the torque constant Kth by the torque command 301 by the torque converter 301, thereby simulating the drive torque by the current command value Ich. On the other hand, as described above, disturbance torque (steering force) that prevents rotation acts on the steering motor 14, and the output of the subtractor 302 that subtracts the disturbance torque from the drive torque contributes to the actual rotation. The rotational torque to be expressed. This rotational torque is divided by the divider 303 by the inertia Jh of the steering motor 14 and converted into the actual angular acceleration of the steering motor 14. This angular acceleration is integrated by an integrator 304 and converted into an actual angular velocity ω of the steering motor 14.

  Conversely, if the rotational torque related to the actual rotation of the steering motor 14 is subtracted from the driving torque corresponding to the driving current that drives the steering motor 14, the steering force that is the disturbance torque can be estimated. Represents. Therefore, if the current command value Ich for driving the steering motor 14 and the angular velocity ω of the steering motor 14 are known, the driving torque and the rotational torque can be calculated, and the disturbance torque that is the difference between them (ie, the steering torque) It is clear that the force can be calculated.

  And the structure of the observer which estimates the steering force using this theory is shown outside the frame of the dashed-dotted line of FIG. The torque constant multiplying unit 311 calculates the drive torque Kth · Ich by multiplying the current command value Ich representing the drive current for driving and controlling the steering motor 14 by the torque constant Kth of the steering motor 14. . The calculation unit 312 calculates the rotational torque s · Jh · ω by multiplying the angular velocity ω of the steering motor 14 by the inertia Jh of the steering motor 14 and performing a differential operation. Then, the subtraction unit 313 subtracts the rotational torque s · Jh · ω from the drive torque Kth · Ich, and estimates and outputs the steering force Th that is a disturbance. Thus, although the steering force Th can be estimated, the steering reaction forces Twl and Twr related to the left and right steering motors 24L and 24R can be similarly estimated.

  However, the estimated steering force Th and the estimated turning reaction forces Twl and Twr in this case correspond to the excess and deficiency of the rotational torque of the steering motor 14 and the left and right steering motors 24L and 24R. Therefore, the positive and negative directions are reversed with respect to the rotation direction of the steering motor 14 and the left and right steering motors 24L and 24R. For this purpose, the calculation unit 143 of the first embodiment is changed to a calculation unit 143 ′ for calculating the estimated steering force Th and the estimated turning reaction forces Twl and Twr by reversing the polarity.

Returning to the description of FIG. 8 again, the steering force estimation unit B7H includes a motor rotation angle conversion unit 201, a differential calculation unit 202, a calculation unit 203, a torque constant multiplication unit 204, a subtraction unit 205, and a calculation unit 206. . In consideration of the fact that the rotation angle θhm of the steering motor 14 is proportional to the steering angle θh of the steering handle 11, the motor rotation angle conversion unit 201 has a predetermined proportional constant to the steering angle θh detected by the steering angle sensor 31. To calculate the rotation angle θhm of the steering motor 14.
The differential calculation unit 202 calculates the rotational speed ω of the steering motor 14 by performing a differential calculation on the rotation angle θhm. When the rotation angle sensor or the rotation angular velocity sensor is built in the steering motor 14 and the rotation angle θhm or the rotation angular velocity ω of the steering motor 14 is detected, these motor rotation angle conversion unit 201 and The differential operation unit 202 is omitted as appropriate.

  The calculation unit 203 corresponds to the calculation unit 312 of FIG. 9 described above, and calculates the rotational torque s · Jh · ω of the steering motor 14 using the steering angular velocity ω. The torque constant multiplication unit 204 corresponds to the torque constant multiplication unit 311 of FIG. 9 described above, and by multiplying the current command value Ich from the current command value calculation unit 151 by the torque constant Kth of the steering motor 14, The drive torque Kth · Ich is calculated. The subtracting unit 205 corresponds to the subtracting unit 313 of FIG. 9 described above, and calculates the steering force Th by subtracting the rotational torque s · Jh · ω from the drive torque Kth · Ich. The output of the subtracting unit 205 is subjected to low-pass filter processing calculation by the calculating unit 206 and output to the calculating unit 143 ′.

  The left turning reaction force estimation unit B7L includes a motor rotation angle conversion unit 211, a differential calculation unit 212, a calculation unit 213, a torque constant multiplication unit 214, a subtraction unit 215, and a calculation unit 216. The motor rotation angle conversion unit 211, the differential calculation unit 212, the calculation unit 213, the torque constant multiplication unit 214, the subtraction unit 215, and the calculation unit 216 are the same as the case of the steering force estimation unit B7H for the steering motor 14 described above. The same. The difference is that a torque constant Ktw and inertia Jw for the left steering motor 24L are used instead of the steering motor 14, and a value representing the left steering reaction force Twl is output from the subtraction unit 215. is there. Also in this case, when the rotation angle sensor or the rotation angular velocity sensor is built in the left steering motor 24L and the rotation angle θwlm or the rotation angular velocity ω of the left steering motor 24L is detected, The motor rotation angle conversion unit 211 and the differential calculation unit 212 are appropriately omitted.

  The right turning reaction force estimation unit B7R includes a motor rotation angle conversion unit 221, a differential calculation unit 222, a calculation unit 223, a torque constant multiplication unit 224, a subtraction unit 225, and a calculation unit 226. The motor rotation angle conversion unit 221, the differential calculation unit 222, the calculation unit 223, the torque constant multiplication unit 224, the subtraction unit 225, and the calculation unit 226 estimate the left turning reaction force for the left turning motor 24L. This is the same as in the case of the part B7L. A different point is that a value representing the right turning reaction force Twr is output from the subtraction unit 225. Also in this case, when the rotation angle sensor or the rotation angular velocity sensor is built in the right steering motor 24R and the rotation angle θwrm or the rotation angular velocity ω of the right steering motor 24R is detected, these The motor rotation angle conversion unit 221 and the differential calculation unit 222 are appropriately omitted.

In the second embodiment configured as described above, the steering force Th is estimated by the steering force estimation unit B7H instead of the steering force Th detected by the steering force sensor 32 of the first embodiment. Further, instead of the left turning reaction force Twl detected by the left turning reaction force sensor 34L of the first embodiment, the turning reaction force Twl is estimated by the left turning reaction force estimation unit B7L. Further, instead of the right turning reaction force Twr detected by the right turning reaction force sensor 34R of the first embodiment, the turning reaction force Twr is estimated by the right turning reaction force estimation unit B7R.
Then, using these estimated steering force Th and left and right steering reaction forces Twl and Twr, the steering motor 14 and the left and right steering motors 24L and 24R are used as in the case of the first embodiment. Bilaterally controlled.

Therefore, also in the second embodiment, as in the case of the first embodiment, the left and right front wheels FWL and FWR that are mechanically separated are directly connected, and the steering handle 11 and the front wheels FWL and FWR are connected to each other. Is connected, the steering reaction force on the steering handle 11 and the steering of the left and right front wheels FWL and FWR are controlled. Accordingly, an appropriate steering reaction force associated with the turning of the front wheels FWL and FWR that are the steered wheels can be applied to the steering handle 11, and the driver can appropriately steer the steering handle 11 while feeling the road reaction force accurately. become able to.
In the second embodiment, the steering force estimation unit B7H and the left and right steering reaction force estimation units B7L and B7R are employed, so that the steering force sensor 32 and the left and right steering reaction force sensor 34L of the first embodiment are used. , 34R can be omitted, the configuration of the apparatus can be simplified, and the manufacturing cost can be reduced.

<First Modification of Second Embodiment>
Next, the steering force estimation unit B7H, the left steering reaction force estimation unit B7L, the right steering reaction force estimation unit B7R, and the drive control units B3, B4, and B5 of the second embodiment are modified. A modification will be described. FIG. 10 shows a functional block configuration of a first modification of the second embodiment, and includes a force response control value calculation unit B2, drive control units B3, B4, B5, a steering force estimation unit B7H, a steering reaction force. Only the estimation units B7L and B7R are shown, and the other parts are the same as those in the second embodiment, and are omitted.
In the first modification, the calculation unit 203 and the subtraction unit 205 of the steering force estimation unit B7H of the second embodiment are replaced with calculation units 203 ′ and 203 ″, an addition unit 205 ′, and a subtraction unit 207. .
In addition, the calculation unit 213 and the subtraction unit 215 of the left steering reaction force estimation unit B7L of the second embodiment are replaced with calculation units 213 ′, 213 ″, an addition unit 215 ′, and a subtraction unit 217.
Further, the calculation unit 223 and the subtraction unit 225 of the right steering reaction force estimation unit B7R of the second embodiment are replaced with calculation units 223 ′, 223 ″, an addition unit 225 ′, and a subtraction unit 227.
Note that these replacements have the same calculation function as that in the second embodiment, and thus function in the same manner as in the second embodiment.

Further, in the drive control unit B3 of the first modified example, the output value of the subtraction unit 207 is divided by the torque constant Kth by the feedback calculation unit 154 and output to the subtraction unit 153. The subtraction unit 153 subtracts the output value from the feedback calculation unit 154 from the current command value Ich from the current command value calculation unit 151 and supplies the subtraction result to the drive circuit 42 as a new current command value Ich.
Similarly, in the drive controller B4, the output value of the subtractor 217 is divided by the torque constant Kth by the feedback calculator 164 and output to the subtractor 163. The subtraction unit 163 subtracts the output value from the feedback calculation unit 164 from the current command value Icl from the current command value calculation unit 161, and supplies the subtraction result to the drive circuit 43L as a new current command value Icl.
Similarly, in the drive control unit B5, the output value of the subtraction unit 227 is divided by the torque constant Kth by the feedback calculation unit 174 and output to the subtraction unit 173. The subtraction unit 173 subtracts the output value from the feedback calculation unit 174 from the current command value Icr from the current command value calculation unit 171 and supplies the subtraction result to the drive circuit 43L as a new current command value Icr.
As a result, the gain of force response control for the steering motor 14 and the left and right steering motors 24L and 24R is increased, and the robustness is improved.
In the example shown in FIG. 10, a steering force estimation unit B7H, a left turning reaction force estimation unit B7L, and a right turning reaction force estimation unit B7R are provided in the first modification of the first embodiment. The present invention may be applied to the first embodiment or its second modification.

<Third Embodiment>
In the first embodiment, the second embodiment, and the modified examples thereof, the left and right independent steering type steering device using the left and right front wheels FWL and FWR as the steered wheels has been described. The present invention can be applied to a steering device in which at least two or more steered wheels are independently steered by a steering actuator, such as a four-wheel independent steered steering device that steers wheels independently.

FIG. 11 shows a schematic configuration of a four-wheel independent steering type steering device as a third embodiment. This steering device is the same as the left and right independent steering type steering device shown in FIG. 1, and further includes a left rear wheel steering unit 20LR, a right rear wheel steering unit 20RR that steers the left and right rear wheels RWL, RWR, and a rear wheel steering system. Drive circuits 43LR and 43RR for driving the units 20LR and 20RR are added.
The left rear wheel steering unit 20LR and the right rear wheel steering unit 20RR have the same configuration as the steering units 20L and 20R that independently steer the left and right front wheels FWL and FWR. The description of each component is abbreviate | omitted by utilizing the code | symbol of the steering parts 20L and 20R, and adding R to the code | symbol end.

In this case, the ECU 41 adjusts the scale of the steering angle θh detected by the steering angle sensor 31 and the steering angles θwl, θwr, θwlr, θwrr detected by the steering angle sensors 33L, 33R, 33LR, 33RR for four wheels. PD control is performed using the averaged average value as the proportional term control command value θ * in the position response control and the differential value of the average value as the differential term control command value dθ * / dt in the position response control. do it.
As for the force response control, the ECU 41 also detects the steering force Th detected by the steering force sensor 32 and the steering reaction forces Twl, Twr, detected by the steering reaction force sensors 34L, 34R, 34LR, 34RR for the four wheels. The force response control value may be calculated based on the resultant force obtained by adjusting Twlr and Twrr and adding them together.

Here, a configuration example of the ECU 41 that drives and controls not only four wheels but also n sets of independent steering sections and one set of steering operation devices will be described with reference to the functional block diagram of FIG.
The example shown in FIG. 12 is a functional configuration of the ECU 41 that controls n sets of steered portions instead of the two sets of steered portions 20L and 20R in the first embodiment. The functional elements that control each of the n sets of steering units are the same as those in the first embodiment shown in FIG. 2 except for the addition unit 102, the average value calculation unit 103, and the calculation unit 143. About the same part, the same code | symbol is attached | subjected in a figure and description is abbreviate | omitted. In this case, about each functional element which controls the 1st steering part, the code | symbol same as the functional element which controls the steering part 20L of 1st Embodiment is attached | subjected, and an nth steering part is controlled. About each functional element to perform, the same code | symbol as the functional element which controls the steering part 20R of 1st Embodiment is attached | subjected.
Moreover, each turning part (1st turning part-nth turning part) is a turning angle sensor (1st turning angle sensor 331-nth turning angle sensor 33n), and a motor for turning (1st 1st turning motor 241 to nth turning motor 24n), driving circuit (first driving circuit 431 to nth driving circuit 43n), turning reaction force sensor (first turning reaction force sensor 341 to 1st) n steering reaction force sensor 34n), each connected to ECU 41.
In the case of the four-wheel independent steering system shown in FIG. 11, n = 4.

In this example, the ECU 41 adjusts the scale of the steering angle θh detected by the steering angle sensor 31 and the turning angles θw1 to θwn detected by the first turning angle sensor 331 to the nth turning angle sensor 33n. The adjusted turning angles α · θw1 to α · θwn are input to the adder 1102 and added. Then, the added value (θh + α · θw1 + α · θw2 + ·· + α · θwn) is output to the average value calculation unit 1103.
The average value calculation unit 1103 calculates the average value by dividing the addition value calculated by the addition unit 1102 by (n + 1). The calculated average value becomes the proportional term control command value θ * in the position response control of the steering motor 14 and the first steering motor 241 to the n-th steering motor 24n.
Further, the differential operation unit 104 performs differential operation on the average value calculated by the average value calculation unit 1103. This differentially calculated value becomes the differential term control command value dθ * / dt in the position response control of the steering motor 14 and the first steering motor 241 to the n-th steering motor 24n.

  On the other hand, regarding the calculation of the force response control value, the ECU 41 multiplies the turning reaction forces Tw1 to Twn detected by the first turning reaction force sensor 341 to the nth turning reaction force sensor 34n by a scale adjustment coefficient β. The value and the steering force Th detected by the steering force sensor 32 are input to the calculation unit 1143. The calculation unit 1143 adds these input values to obtain a resultant force, and outputs this resultant force to the gain multiplication unit 144. The gain multiplication unit 144 multiplies the output value of the calculation unit 1143 by the proportional term gain Ktp for force response control, outputs the multiplied value to the calculation units 160 and 170, and passes through the scale adjustment unit 145. To the calculation unit 150.

Thus, the steering motor 14 and the n sets of steering motors 241 to 24n are in a state in which n sets of steered wheels that are mechanically separated are connected to the steering handle 11 by bilateral control. The steering reaction force on the steering handle 11 and the turning of the steered wheels are controlled. Therefore, even if the steering device includes n sets of independent steered wheels, an appropriate steering reaction force accompanying the steering of each steered wheel can be given to the steering handle 11, and the driver can accurately perform the road surface reaction force. The steering handle 11 can be steered satisfactorily while feeling the above.
The scale adjustment coefficients α and β can be arbitrarily set for each steered wheel.
Further, in other embodiments and modifications thereof, it is also possible to apply to a steering apparatus provided with n sets of independent steered wheels.

  Although the embodiments of the present invention and the modifications thereof have been described above, the present invention is not limited to the above-described embodiments and modifications, and various modifications can be made without departing from the object of the present invention. It is.

  For example, in each of the above-described embodiments and modifications thereof, the position response control value calculation unit B1 performs position control of the steering motor 14 and the steering motors 24L and 24R by PD (proportional / differential) control. did. However, instead of this, PID (proportional / differential / integral) control to which an integral term is further added may be adopted. Further, the differential term may be omitted, and the position control of the steering motor 14 and the steering motors 24L and 24R may be performed only by P (proportional) control.

  In each of the above embodiments and their modifications, the force response control value calculation unit B2 performs force control of the steering motor 14 and the steering motors 24L and 24R by P (proportional) control. . However, instead of this, PI (proportional / differential) control to which a differential control term is added may be adopted. Further, by adding an integral term, force control of the steering motor 14 and the steering motors 24L and 24R may be performed by PID (proportional / differential / integral) control.

  In each of the above-described embodiments and their modifications, predetermined constants are used as the scale adjustment coefficients α and β. However, instead of this, these scale adjustment coefficients α and β may be changed according to the running state of the vehicle. In this case, as described above, the scale adjustment coefficient α is a coefficient for causing the steering angle θh to correspond to the steering angles θwl and θwr, and the scale adjustment coefficient β is used for the steering reaction forces Twl and Twr as the steering force. It is a coefficient for making it correspond to Th. Therefore, controlling the scale adjustment coefficient α in accordance with the running state of the vehicle changes the ratio between the steering angle θh and the turning angles θwl and θwr controlled by the position response control value calculation unit B1 to the running state of the vehicle. It means to change accordingly. Further, controlling the scale adjustment coefficient β in accordance with the running state of the vehicle means that the ratio of the steering force Th and the turning reaction force Twl, Twr controlled by the force response control value calculation unit B2 is the running state of the vehicle. It means to change according to.

  Thus, in order to change the scale adjustment coefficients α and β according to the traveling state of the vehicle, for example, as shown by a broken line in FIG. 1, a vehicle speed sensor 41 for detecting the vehicle speed V is provided, and the vehicle speed is set in the ECU 41. A table that stores scale adjustment coefficients α and β that change according to V or a function that defines scale adjustment coefficients α and β that change according to vehicle speed V is prepared, and scale adjustment is performed by ECU 41 according to vehicle speed V. The coefficients α and β may be determined.

  For example, the scale adjustment coefficient α used in each of the above embodiments is a constant αo, and the scale adjustment coefficient α is defined to increase in the vicinity of the constant αo as the vehicle speed V increases as shown in FIG. In this case, the turning angles θwl and θwr of the left and right front wheels FWL and FWR are controlled so as to decrease as the vehicle speed V increases with respect to the same steering angle θh of the steering handle 11. According to this, the turning performance of the vehicle becomes good in the low speed range, and the running stability of the vehicle in the high speed range becomes good.

  Further, the scale adjustment coefficient α used in each of the above embodiments is a constant αo, and as shown in FIG. 13B, the scale adjustment coefficient α is defined so as to decrease in the vicinity of the constant αo as the steering angle θh increases. In this case, the turning angles θwl and θwr of the left and right front wheels FWL and FWR are controlled to increase as the steering angle θh of the steering wheel 11 increases. According to this, the small turning performance of the vehicle at the time of large steering angle steering is improved.

  In addition, the scale adjustment coefficient β used in each of the above embodiments is a constant βo, and the scale adjustment coefficient β is specified to decrease near the constant βo as the vehicle speed V increases as shown in FIG. In this case, the steering force (steering reaction force) of the steering handle 11 is controlled to increase as the vehicle speed V increases. According to this, the steering handle 11 is steered lightly in the low speed range, the steering operation of the steering handle 11 in the high speed range becomes heavy, and the running stability of the vehicle becomes good.

  Further, the scale adjustment coefficient β used in each of the above embodiments is a constant βo, and as shown in FIG. 13D, the scale adjustment coefficient β is defined to increase in the vicinity of the constant βo as the steering angle θh increases. In this case, the steering force (steering reaction force) of the steering handle 11 is controlled to decrease as the steering angle θh increases. According to this, the steering operation of the steering handle 11 at the time of large steering angle steering can be performed lightly.

  Furthermore, the scale adjustment coefficients α and β may be changed according to changes in both the vehicle speed V and the steering angle θh. Furthermore, not only the vehicle speed V and the steering angle θh, but also the scale adjustment coefficients α and β may be changed in accordance with physical quantities representing the vehicle running state such as lateral acceleration and yaw rate.

  Further, in each of the above embodiments and their modifications, the scale adjustment units 101 and 111 multiply the turning angles θwl and θwr, which are output values of the left and right turning angle sensors 33L and 33R, by a scale adjustment coefficient α. I did it. However, instead of this, the steering angle θh that is the output of the steering angle sensor 31 may be multiplied by a scale adjustment coefficient α ′ corresponding to the scale adjustment coefficient α. In this case, the scale adjustment coefficient α ′ is changed in a direction opposite to the scale adjustment coefficient α in each of the above-described embodiments with respect to changes in physical quantities representing the running state of the vehicle such as the vehicle speed V and the steering angle θh. Like that. In the case of this modification, the scale adjustment unit 145 of each of the above embodiments is omitted, and the control value given to the calculation units 160 and 170 from the gain multiplication unit 144 (or the force response reduction coefficient multiplication unit 146) is set. The scale adjustment for multiplying the scale adjustment coefficient α ′ is provided on the input side of the calculation sections 160 and 170 to which the output value from the gain multiplication section 144 (or the force response reduction coefficient multiplication section 146) is supplied.

  In each of the above-described embodiments and their modifications, the scale adjustment coefficient β is added to the output values of the left and right turning reaction force sensors 34L and 34R or the calculation unit 216 (or calculation unit 226) in the scale adjustment units 141 and 142. Was multiplied. However, instead of this, a scale adjustment unit is provided between the steering force sensor 32 or calculation unit 206 (or subtraction unit 207) and the calculation unit 143 or calculation unit 143 ′, and the scale adjustment unit uses the steering force sensor. 32 or the output value of the calculation unit 206 (or subtraction unit 207) may be multiplied by a scale adjustment coefficient β ′ corresponding to the scale adjustment coefficient β. In this case, the scale adjustment coefficient β ′ is changed in the opposite direction to the scale adjustment coefficient β in each of the above-described embodiments with respect to changes in physical quantities representing the running state of the vehicle such as the vehicle speed V and the steering angle θh. Like that. In the case of this modification, the scale adjustment unit 118 in each of the above embodiments is omitted, and the control value given from the addition unit 127 to the inertia multiplication unit 129 and the addition value from the addition unit 137 to the inertia multiplication unit 139. A scale adjustment unit that multiplies the control value by the scale adjustment coefficient β ′ is interposed between the addition unit 127 and the inertia multiplication unit 129 and between the addition unit 137 and the inertia multiplication unit 139. Furthermore, both the scale adjustment coefficients α and β of the above embodiments and the scale adjustment coefficients α ′ and β ′ of the modification may be considered.

1 is an overall schematic diagram of a vehicle steering apparatus according to a first embodiment of the present invention. It is a functional block diagram showing the function implement | achieved by the electronic control unit which concerns on 1st Embodiment. It is a functional block diagram showing the function implement | achieved by the electronic control unit which concerns on the 1st modification of 1st Embodiment. It is a flowchart showing the function of the force response reduction coefficient multiplication part which concerns on the 1st modification of 1st Embodiment. It is a graph showing the reduction coefficient table which concerns on the 1st modification of 1st Embodiment. It is a graph showing the return reduction coefficient table which concerns on the 1st modification of 1st Embodiment. It is a functional block diagram showing the function implement | achieved in the electronic control unit which concerns on the 2nd modification of 1st Embodiment. It is a functional block diagram showing the function implement | achieved by the electronic control unit which concerns on 2nd Embodiment. It is a block diagram of the disturbance observer regarding the electric motor for steering. It is a functional block diagram showing the function implement | achieved in the electronic control unit which concerns on the 1st modification of 2nd Embodiment. It is a whole schematic diagram of the steering device of vehicles concerning a 3rd embodiment. It is a functional block diagram showing the function implement | achieved by the electronic control unit which concerns on 3rd Embodiment. (A) is a graph showing the change of the scale adjustment coefficient α according to the vehicle speed, (B) is a graph showing the change of the scale adjustment coefficient α according to the steering angle, and (C) is a graph of the scale adjustment coefficient β. It is a graph which shows the change according to a vehicle speed, (D) is a graph which shows the change according to the steering angle of the scale adjustment coefficient (beta).

Explanation of symbols

FWL, FWR: front wheel, RWL, RWR ... rear wheel, 10 ... steering operation device, 11 ... steering handle, 14 ... electric motor for steering, 20 ... steering device, 20L, 20R, 20LR, 20RR ... steering unit, 24L , 24R, 24LR, 24RR ... steering electric motor, 31 ... steering angle sensor, 32 ... steering force sensor, 33L, 33R, 33LR, 33RR ... steering angle sensor, 34L, 33R, 33LR, 33RR ... steering reaction force Sensor, 41 ... Electronic control unit (ECU), 42, 43L, 43R, 43LR, 43RR ... Drive circuit, B1 ... Position response control value calculation unit, B2 ... Force response control value calculation unit, B3, B4, B5 ... Drive control B6H, B6L, B6R ... damping control unit, B7H ... steering force estimation unit, B7L, B7R ... steering reaction force estimation unit.

Claims (9)

Steer-by-wire vehicle steering apparatus comprising: a steering actuator that drives the steering handle; and at least two or more steered actuators that independently steer a plurality of steered wheels that are not mechanically connected to the steering handle. In
Steering angle acquisition means for acquiring steering angle information representing the steering angle of the steering wheel;
For each steered wheel steered independently by each steered actuator, steered angle obtaining means for obtaining steered angle information representing the steered angle;
Steering force acquisition means for acquiring steering force information representing the steering force applied to the steering handle;
For each steered wheel steered independently by each steered actuator, steered reaction force acquisition means for obtaining steered reaction force information representing the steered reaction force input to the steered wheel; and
An average value calculating means for calculating an average value obtained by scaling and averaging the steering angle represented by the steering angle information and the turning angle for each steered wheel represented by the turning angle information;
Based on the average value calculated by the average value calculation means, position response control values for the steering actuator and the turning actuator for maintaining the steering angle of the steering wheel and the turning angle of each steered wheel at a predetermined ratio are obtained. Position response control value calculation means for calculating;
A resultant force calculation means for calculating a combined force by adjusting a scale of the steering force represented by the steering force information and the turning reaction force for each steered wheel represented by the turning reaction force information;
Based on the resultant force calculated by the resultant force calculation means, a force response control value for the steering actuator and the turning actuator is calculated according to the steering force applied to the steering wheel and the turning reaction force input to each turning wheel. Force response control value calculating means for
The position response control value for the steering actuator calculated by the position response control value calculation means and the force response control value for the steering actuator calculated by the force response control value calculation means are summed to drive the steering actuator Steering actuator drive control means for controlling;
The position response control value for the steered actuator calculated by the position response control value calculating means and the force response control value for the steered actuator calculated by the force response control value calculating means are added together to form the steered wheel. A vehicle steering apparatus comprising: a steering actuator drive control means for driving and controlling the actuator. Road surface state detecting means for detecting a road surface state on which the vehicle travels;
Force response control value correcting means for reducing the force response control value calculated by the force response control value calculating means when the road surface condition detecting means determines that the road surface condition level is at a predetermined rough road level. The vehicle steering apparatus according to claim 1, further comprising: The steered actuator includes a left steered actuator that steers left steered wheels, and a right steered actuator that steers right steered wheels,
The turning reaction force acquisition means includes a left turning reaction force information indicating a left turning reaction force input to the left turning wheel and a right turning reaction force indicating a right turning reaction force input to the right turning wheel. It is configured to acquire reaction force information separately,
The road surface state detecting means is based on a difference between a left turning reaction force represented by the left turning reaction force information and a right turning reaction force represented by the right turning reaction force information. The vehicle steering apparatus according to claim 2, wherein: The steering angle acquisition means is a steering angle sensor that detects a steering angle of a steering wheel,
The turning angle acquisition means is a turning angle sensor that detects a turning angle of each turning wheel,
The steering force acquisition means is a steering force sensor that detects a steering force applied to a steering handle, and
The vehicle steering apparatus according to any one of claims 1 to 3, wherein the turning reaction force acquisition means is a turning reaction force sensor that detects a turning reaction force input to each steered wheel. The steering force acquisition means is a steering force estimation means for estimating a steering force applied to a steering wheel based on an operation control state of the steering actuator and an actual operation state of the steering actuator; and
The turning reaction force acquisition means estimates the turning reaction force input to the steered wheel based on the operation control state of the turning actuator and the actual operation state of the turning actuator. The vehicle steering apparatus according to any one of claims 1 to 3, wherein the vehicle steering apparatus is estimation means. Steering angular velocity calculation means for calculating a steering angular velocity based on the steering angle represented by the steering angle information;
A damping control means is provided for calculating a damping control value proportional to the calculated steering angular velocity, and adding the damping control value to the steering actuator drive control by the steering actuator drive control means. Item 6. The vehicle steering device according to any one of Items 1 to 5. A turning angular velocity calculating means for calculating a turning angular velocity based on the turning angle represented by the turning angle information;
Damping control means for calculating a damping control value proportional to the calculated turning angular velocity and adding the damping control value to the drive control of the turning actuator by the turning actuator drive control means is provided. A vehicle steering apparatus according to any one of claims 1 to 6.   In the average value calculation means, the scale adjustment ratio between the steering angle represented by the steering angle information and the turning angle for each steered wheel represented by the turning angle information is changed according to the traveling state of the vehicle. The vehicle steering apparatus according to claim 1, further comprising a first changing unit configured to perform the first changing unit. In the resultant force calculation means, the scale adjustment ratio between the steering force represented by the steering force information and the steering reaction force for each steered wheel represented by the steering reaction force information is determined according to the traveling state of the vehicle. The vehicle steering apparatus according to any one of claims 1 to 8, further comprising second changing means for changing.

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